On this page you will find a list of peer-reviewed scientific publications from the project.
Reviewed articles 2020
Have we reached the turning point? Looking for evidence of SOC increase under conservation agriculture and cover crop practices?
C. Camarotto, I. Piccoli, N. Dal Ferro, R. Polese, F. Chiarini, L. Furlan, F. Morari
Increasing soil organic carbon (SOC) stocks in agricultural soils is currently of special interest because it can help mitigate global warming through atmospheric carbon (C) sequestration. Recommended management practices, such as conservation agriculture (CA) and conventional tillage with cover crops (CC), could have significant implications for C sequestration potential. A field experiment was carried out in Northeast Italy to compare the implementation of CA and CC with conventional agriculture (CV). The experiment began in 2010 on three farms to evaluate SOC stock variation over a 6‐yr period. Two extensive soil sampling operations were conducted in 2011 and 2017 in 240 locations, for a total of 1,440 analysed soil samples, considering the SOC stratification within a 0–50 cm profile. The results suggested that CA changed the SOC distribution rather than the total amount of SOC. Compared to CV, after the introduction of CA, a general increase in SOC (0.25 Mg C ha−1 y−1) was observed in the 0–30 cm layer, while no stock variation was observed in the 0–50 cm layer. In contrast, compared to CV, the use of CC decreased the SOC stocks by 0.74 Mg C ha−1 y−1 in the 0–50 cm layer. Over a 6‐yr period, no benefit in SOC sequestration was observed with CA and CC. However, we hypothesise that these findings could still be affected by transitory dynamics, highlighting the low soil reactivity to soil‐improving agricultural systems. A longer study period would be required to better understand the potential benefits of CA and CC on SOC sequestration.
European Journal of Soil Science
Stakeholder Perspectives to Prevent Soil Organic Matter Decline in Northeastern Italy
Nicola Dal Ferro,Carlo Camarotto,Ilaria Piccoli,Antonio Berti,Jane Mills and Francesco Morari
A transition from conventional to more sustainable soil management measures (SMMs) is required to reverse the current soil organic matter (SOM) losses in the agroecosystems. Despite the innovations and technologies that are available to prevent SOM decline, top–down knowledge transfer schemes that incentivize a certain measure are often ineffective. Here, we discuss relevant outcomes from a participatory approach where researchers, farmers, practitioners and government officials have discussed opportunities and barriers around SMM application to prevent SOM decline. Within a series of workshops, stakeholders identified, scored, and selected SMMs to field-tests and evaluated the benefits and drawbacks from their application. Results showed that the stakeholders recognized the need for innovations, although they valued the most promising SMM as already available continuous soil cover and conservation agriculture. In contrast, more innovative SMMs, such as biochar use and the variable rate application of organic amendments through precision farming, were the least valued, suggesting that people’s resistance to new technologies is often governed by the socio-cultural perception of them that goes beyond the economic and technological aspects. The valuation of benefits and drawbacks by stakeholders on trialed measures emphasized that stakeholders’ perspective about soil management is a combination of economic, environmental, and socio-cultural aspects, thus corroborating the need for transdisciplinary bottom–up approaches to prevent SOM depletion and increase soil rehabilitation and SOM content.
Sustainability 2020, 12(1), 378
Reviewed articles 2019
Wheel load, repeated wheeling, and traction effects on subsoil compaction in northern Europe
Mansonia Pulido-Moncada, Lars J. Munkholm, Per Schjønning
Traffic in agricultural fields with very high wheel loads imposes a risk of severe structural damage deep into the subsoil. However, there is a paucity of studies quantifying these effects. This study focuses on heavy traffic induced changes in soil structure for a sandy loam soil in a temperate region. The treatments included no compaction (Control), compaction with ∼3 Mg (M3) and ∼8 Mg (M8) wheel loads with multiple (4–5) wheel passes, and compaction with a single-pass wheel load of ∼12 Mg (S12). The compaction treatments were replicated four consecutive years. Subsoil structural quality was evaluated visually by the SubVESS method, and soil pore characteristics were quantified for minimally disturbed soil cores sampled at 30, 50, 70 and 90 cm depth two years after the end of the experiment. Our results indicate that M8 significantly affected soil structural properties to>50 cm depth in terms of reduced subsoil structural quality, air-filled pore space, air permeability, gas diffusivity, pore volume and increased bulk density. Results also showed that the degree of compactness was ≥95% for M8 at 30 and 50 cm depth. Even though a pre-existing dense soil matrix was described in the studied soil, results confirmed that high wheel loads may cause significant subsoil compaction at>50 cm depth. Surprisingly, the S12 treatment did not show marked signs of decreasing structural quality at depth. Thus, our results indicate that primarily traffic applying multiple passes with high wheel loads compromises soil structure at depth. The S12 results further suggest the need to investigate the influence of factors other than wheel load and inflation pressure on the risk of subsoil compaction.
Soil & Tillage Research 186 (2019) 300-309
Coupling gas transport measurements and X-ray tomography scans for multiscale analysis in silty soils
I. Piccoli, P. Schjønning, M. Lamandé, F. Zanini, F. Morari
Scale is a key issue in soil studies. The idea that a sample must be of adequate size to embody a specific physical property comes from the representative elementary volume (REV) concept that defines minimum sample size for consistent results. Other approaches to describe soil spatial heterogeneity rely on the fractal dimension concept (FDC), which assumes structure changes with scale continuously, and the discrete hierarchy concept (DHC), which assumes change occurs discretely. This study considered using gas transport measurements combined with X-ray computed micro-tomography (μCT) for multi-scale analyses. Specifically, 24 large (“L cores”, 628.3 cm3) core volume samples were collected from two farms and two soil depths (3–11 cm and 20–28 cm) in northeast Italy. Gas transport parameters, such as air-filled porosity, air permeability, and gas diffusivity, were measured on the original cores and on successively sub-sampled medium (“M cores”, 100.4 cm3) and small (“S cores”, 4.7 cm3) cores. X-ray μCT–derived porosity indices were calculated for the two smaller scales. Soil core sub-sampling resulted in reduced soil gas transport property measurements, especially in the deepest depth when related to large and continuous bio-pore decreases in root channels and wormholes. In small core volumes, the pore network was dominated by small isolated pores, which might obstruct gas diffusion at that scale. All three concepts named above could be reconciled with our data. The limited numbers of samples and observation scales hindered identifying which model described soil spatial heterogeneity best. Finally, our results suggested the importance of considering scale effects on soil physical properties and their measurement consistency.
Geoderma Volume 338, 15 March 2019, Pages 576-584
Reviewed articles 2019
Assessing Impacts of Soil Management Measures on Ecosystem Services
Gudrun Schwilch,Tatenda Lemann, Örjan Berglund, Carlo Camarotto, Artemi Cerdà, Ioannis N. Daliakopoulos 6, Silvia Kohnová, Dominika Krzeminska, Teodoro Marañón, René Rietra, Grzegorz Siebielec, Johann Thorsson, Mark Tibbett, Sandra Valente, Hedwig Van Delden, Jan Van den Akker, Simone Verzandvoort, Nicoleta Olimpia Vrînceanu, Christos Zoumides and Rudi Hessel
Only a few studies have quantified and measured ecosystem services (ES) specifically related to soil. To address this gap, we have developed and applied a methodology to assess changes in ecosystem services, based on measured or estimated soil property changes that were stimulated by soil management measures (e.g., mulching, terracing, no-till). We applied the ES assessment methodology in 16 case study sites across Europe representing a high diversity of soil threats and land use systems. Various prevention and remediation measures were trialled, and the changes in manageable soil and other natural capital properties were measured and quantified. An Excel tool facilitated data collection, calculation of changes in ecosystem services, and visualization of measured short-term changes and estimated long-term changes at plot level and for the wider area. With this methodology, we were able to successfully collect and compare data on the impact of land management on 15 different ecosystem services from 26 different measures. Overall, the results are positive in terms of the impacts of the trialled measures on ecosystem services, with 18 out of 26 measures having no decrease in any service at the plot level. Although methodological challenges remain, the ES assessment was shown to be a comprehensive evaluation of the impacts of the trialled measures, and also served as an input to a stakeholder valuation of ecosystem services at local and sub-national levels.
Sustainability 2018, 10(12), 4416;
Ectomycorrhizal Fungal Communities and Their Functional Traits Mediate Plant–Soil Interactions in Trace Element Contaminated Soils
Marta Gil-Martínez, Álvaro López-García, María T. Domínguez, Carmen M. Navarro-Fernández, Rasmus Kjøller, Mark Tibbett and Teodoro Marañón
There is an increasing consensus that microbial communities have an important role in mediating ecosystem processes. Trait-based ecology predicts that the impact of the microbial communities on ecosystem functions will be mediated by the expression of their traits at community level. The link between the response of microbial community traits to environmental conditions and its effect on plant functioning is a gap in most current microbial ecology studies. In this study, we analyzed functional traits of ectomycorrhizal fungal species in order to understand the importance of their community assembly for the soil–plant relationships in holm oak trees (Quercus ilex subsp. ballota) growing in a gradient of exposure to anthropogenic trace element (TE) contamination after a metalliferous tailings spill. Particularly, we addressed how the ectomycorrhizal composition and morphological traits at community level mediate plant response to TE contamination and its capacity for phytoremediation. Ectomycorrhizal fungal taxonomy and functional diversity explained a high proportion of variance of tree functional traits, both in roots and leaves. Trees where ectomycorrhizal fungal communities were dominated by the abundant taxa Hebeloma cavipes and Thelephora terrestris showed a conservative root economics spectrum, while trees colonized by rare taxa presented a resource acquisition strategy. Conservative roots presented ectomycorrhizal functional traits characterized by high rhizomorphs formation and low melanization which may be driven by resource limitation. Soil-to-root transfer of TEs was explained substantially by the ectomycorrhizal fungal species composition, with the highest transfer found in trees whose roots were colonized by Hebeloma cavipes. Leaf phosphorus was related to ectomycorrhizal species composition, specifically higher leaf phosphorus was related to the root colonization by Thelephora terrestris. These findings support that ectomycorrhizal fungal community composition and their functional traits mediate plant performance in metal-contaminated soils, and have a high influence on plant capacity for phytoremediation of contaminants. The study also corroborates the overall effects of ectomycorrhizal fungi on ecosystem functioning through their mediation over the plant economics spectrum.
Front. Plant Sci., 20 November 2018
Copper distribution in European topsoils: An assessment based on LUCAS soil survey
Ballabio, C., Panagos, P., Lugato, E., Huang, J.-H., Orgiazzi, A., Jones, A., Fernández-Ugalde, O., Borrelli, P., Montanarella, L.
Copper (Cu) distribution in soil is influenced by climatic, geological and pedological factors. Apart from geological sources and industrial pollution, other anthropogenic sources, related to the agricultural activity, may increase copper levels in soils, especially in permanent crops such as olive groves and vineyards. This study uses 21,682 soil samples from the LUCAS topsoil survey to investigate copper distribution in the soils of 25 European Union (EU) Member States.
Science of the Total Environment, 636, pp. 282-298
Potential sources of anthropogenic copper inputs to European agricultural soils
Panagos, P., Ballabio, C., Lugato, E., Jones, A., Borrelli, P., Scarpa, S., Orgiazzi, A., Montanarella, L.
In the European Union (EU), copper concentration in agricultural soil stems from anthropogenic activities and natural sources (soil and geology). This manuscript reports a statistical comparison of copper concentrations at different levels of administrative units, with a focus on agricultural areas. Anthropogenic sources of diffuse copper contamination include fungicidal treatments, liquid manure (mainly from pigs), sewage sludge, atmospheric deposition, mining activities, local industrial contamination and particles from car brakes. Sales of fungicides in the EU are around 158,000 tonnes annually, a large proportion of which are copper based and used extensively in vineyards and orchards. Around 10 million tonnes of sewage sludge is treated annually in the EU, and 40% of this (which has a high copper content) is used as fertilizer in agriculture. In the EU, 150 million pigs consume more than 6.2 million tonnes of copper through additives in their feed, and most of their liquid manure ends up in agricultural soil. These three sources (sales of fungicides, sewage sludge and copper consumption for pigs feed) depend much on local traditional farming practices. Recent research towards replacing copper spraying in vineyards and policy developments on applying sewage and controlling the feed given to pigs are expected to reduce copper accumulation in agricultural soil.
Sustainability (Switzerland), 10 (7), art. no. 2380
Quantifying the effectiveness of mountain terraces on soil erosion protection with sediment traps and dry-stone wall laser scans
Camera, C., H. Djuma, A. Bruggeman, C. Zoumides, M. Eliades, K. Charalambous, D. Abate, M. Faka.
Mountain depopulation in the Mediterranean region over the past decades has led to a decline in the use and maintenance of agricultural terraces and consequently the collapsing of dry-stone walls, which can increase soil erosion rates and downstream sedimentation. A field experiment has been set up on a degrading terraced hillslope in the Troodos Mountains of Cyprus, to quantify the effectiveness of terrace maintenance on protecting cultivated land against soil erosion. The monitored site is cultivated with grapes. The terrace riser (22 m long) that forms the linear outlet of the hillslope has 11.4 m of standing dry-stone wall and 10.6 m of collapsed wall. It has been instrumented with seven 1 m wide sediment traps, three on standing sections of the wall and four on collapsed sections. When dry, sediment was collected from the traps after rainfall events, from December 2015 to November 2017. Uncertainties in the drainage areas of the 31.5-m long slope were quantified both for the terrace wall and for the individual traps through hydrologic delineations based on a detailed topographic survey. The sediment data were complemented by laser scanner surveys that were conducted in November 2015, May 2016 and April 2017, on a dry-stone terrace wall upslope from the outlet section. Wall degradation was assessed from the consecutive 3D model reconstructions. Rainfall was 469 mm in the first year and 515 mm in the second year and the average erosivity was 1148 MJ mm ha−1 h−1 y−1. The average soil erosion rate was 2.4 Mg ha−1 y−1, when linear drainage areas are considered (693 m2), 3.2 Mg ha−1 y−1 when the borders are delineated with the topographic data (520 m2). Nearly half of the soil erosion (43%) occurred during two very intense rainfall events (maximum 30-min intensity exceeding 35 mm h−1), out of the 34 monitored events. Erosion from standing terrace sections was 3.8 less than the erosion from the collapsed sections. For the scanned terrace wall, soil erosion from the standing sections was 2.2 lower than from the degraded sections. The laser scanner surveys identified some preferential erosion paths, but failed to recognize single stone collapses, whereas possible wall displacement was masked by scanning artifacts. The sediment traps were found to be an effective method for understanding and quantifying soil erosion in terraced mountain environments, while further research is needed to develop a more rigorous acquisition procedure for laser scanner surveys to derive useful information on wall degradation.
Catena 171: 251-264.
A Bayesian belief network framework to predict SOC dynamics of alternative management scenarios.
Dal Ferro, N., Quinn, C. and Morari, F.,
Understanding the key drivers that affect a decline of soil organic carbon (SOC) stock in agricultural areas is of major concern since leading to a decline in service provision from soils and potentially carbon release into the atmosphere. Despite an increasing attention is given to SOC depletion and degradation processes, SOC dynamics are far from being completely understood because they occur in the long term and are the result of a complex interaction between management and pedo-climatic factors. In order to improve our understanding of SOC reduction phenomena in the mineral soils of Veneto region, this study aimed to adopt an innovative probabilistic Bayesian belief network (BBN) framework to model SOC dynamics and identify management scenarios that maximise its accumulation and minimise GHG emissions. Results showed that the constructed BBN framework was able to describe SOC dynamics of the Veneto region, predicting probabilities of general accumulation (11.0%) and depletion (55.0%), similar to those already measured in field studies (15.3% and 50%, respectively). A general enhancement in the SOC content was observed where a minimum soil disturbance was adopted. This outcome suggested that management strategies of conversion from croplands to grasslands, no tillage and conservation agriculture are the most promising management strategies to reverse existing SOC reduction dynamics. Moreover, measures implying SOC stocks were also those providing major benefits in terms of GHGs reduction emissions. Finally, climate change scenarios slightly affected management practice. Advancements in our BBN framework might include more detailed classes at higher resolution as well as any socio-cultural or economic aspect that should improve the evaluation of prediction scenarios.
Soil and Tillage Research, 179, pp.114-124.
Effects of biochar on the dynamics of aggregate stability in clay and sandy loam soils
C. Pituello N. Dal Ferro O. Francioso G. Simonetti A. Berti I. Piccoli A. Pisi F. Morari
Recent advances suggest that organic substances of different origins might have different aggregate stability dynamics. We investigated the extent to which contrasting soil types affect the dynamics of aggregation after the addition of crop residues (R) and of biochar at two doses (BC20, 20 Mg ha−1; BC40, 40 Mg ha−1) in a 2‐year experiment. To evaluate disaggregation, we measured a set of physical–chemical and structure‐related properties of clay and sandy loam aggregates sieved to 1–2 mm, including wet aggregate stability after different pretreatments combined with laser diffraction analysis. The electrochemical properties of the colloidal suspension were also analysed to identify changes in soil chemistry affected by organic inputs. Different amounts of added biochar and soil types produced contrasting effects on wet aggregate stability. In sandy loam, the increased soil surface area from added biochar (at either dose) offset the initial small soil organic carbon (SOC) content and subsequently promoted SOC‐controlled aggregation. Conversely in clay soil, the larger biochar dose (BC40) strengthened the repulsive forces between particles with the same charge and monovalent cations, which led to chemical perturbation and some aggregate breakdown not found with BC20. Pore structure also changed in clay aggregates. A shift towards more micropores (30–5 μm, + 29% more than in the control) and ultramicropores (5–0.1 μm, + 22% more than in the control), which contributed to aggregate stabilization, resulted when biochar was added, but not for residue. Our results suggest that biochar promotes aggregate stability, which, in turn, improves the physical fertility of soil, especially if it has a coarse texture and small organic carbon content. Further study is needed of the physical–chemical interactions between added biochar and surface‐charged clay‐rich soils.
European Journal of Soil Science
Exploring the labour productivity of agricultural systems across European regions: A multilevel approach
Elias Giannakis and Adriana Bruggeman
Agricultural productivity varies greatly among agricultural systems and among regions in Europe. A multilevel logistic regression model was applied to investigate the labour productivity of the six main agricultural systems across European NUTS2 regions. K-means and two-step clustering methods were used to classify European regions based on the agricultural systems’ standard output per annual work unit. We analysed the effect of environmental (soil erosion, rainfed yield potential), structural (farm education, age, pluriactivity, diversification, rented agricultural land), technical (yield ratio) and contextual (gross domestic product per capita, population density) factors on labor productivity. Significant differences were revealed between northern-central regions and the continental peripheries (Mediterranean, Eastern). Soil erosion negatively affects agricultural labour productivity; for each one ton/ha increase in the modelled annual soil erosion rate the odds of regions to attain high labour productivity decreased by 28%. The importance of technical efficiency in crop production was also identified. Observed low wheat yields, relative to modelled potential yields, in the southern, eastern and northern European regions indicate a large unexploited gap. The positive effect of the regional gross domestic product per capita and the low population density confirmed the importance of contextual factors on labour productivity. A second analysis of a composite indicator of the labour productivity of the European agricultural systems, which accounted for the productivity of each system without considering its size, revealed the positive effect of farm education and the negative effect of pluriactivity on agricultural labour productivity. The analyses indicate the importance of compensatory allowances for areas facing natural constraints, while investing in farm training schemes and advisory services could increase the adoption of new technologies and improve the performance of farmers in both economic and environmental terms. Finally, the significance of contextual factors indicates the importance of a better harmonisation of rural development policy with regional policy.
Land Use Policy Volume 77, September 2018, Pg 94-106
Soil-plant relationships and contamination by trace elements: A review of twenty years of experimentation and monitoring after the Aznalcóllar (SW Spain) mine accident
Paula Madejón, María T. Domínguez, Engracia Madejón, Francisco Cabrera, Teodoro Marañón, and José M. Murillo.
Soil contamination by trace elements (TE) is a major environmental problem and much research is done into its effects on ecosystems and human health, as well as into remediation techniques. The Aznalcóllar mine accident (April 1998) was a large-scale ecological and socio-economic catastrophe in the South of Spain. We present here a literature review that synthesizes the main results found during the research conducted at the affected area over the past 20 years since the mine accident, focused on the soil-plant system. We review, in depth, information about the characterization of the mine slurry and contaminated soils, and of the TE monitoring, performed until the present time. The reclamation techniques included the removal of sludge and soil surface layer and use of soil amendments; we review the effects of different types of amendments at different spatial scales and their effectiveness with time. Monitoring of TE in soil and their transfer to plants (crops, herbs, shrubs, and trees) were evaluated to assess potential toxicity effects in the food web. The utility of some plants (accumulators) with regard to the biomonitoring of TE in the environment was also evaluated. On the other hand, retention of TE by plant roots and their associated microorganisms was used as a low-cost technique for TE stabilization and soil remediation. We also evaluate the experience acquired in making the Guadiamar Green Corridor a large-scale soil reclamation and phytoremediation case study.
Science of The Total Environment 625 (2018): 50-63.
Reviewed articles 2017
The Forchheimer Approach for Soil Air Permeability Measurement
Per Schjønning and Michael Koppelgaard
Air permeability affects a range of soil functions and is useful in the quantification of soil pore characteristics. Measurements of air flow used to quantify air permeability are mostly performed at a fixed pressure difference, assuming a linear relation between flow and pressure. However, evidence exists that nonlinear pressure losses may occur even at low pressure gradients. We constructed an apparatus that allows automatic measurement of air flow at a range of pressures. The new methodology was applied to eight soil samples deriving from a loamy, Stagnic luvisol. Three artificial cores were also tested: a solid cylinder of plastic with drilled, vertical holes; a cylinder of autoclaved aerated concrete (AAC), and an AAC cylinder with drilled holes. The historical Forchheimer approach, including a polynomial regression of flow–pressure data, was applied to derive the true Darcian flow based on the coefficient to the linear part of the relation. Flow-pressure data appeared to be curvilinear for all test specimens, except for one of the soil samples. The results showed up to 65% errors in estimates of air permeability if the nonlinear pressure losses were ignored when applying a pressure difference as low as 100 Pa. Our results strongly suggest use of the Forchheimer approach based on measurements of flow and pressure difference at a range of air pressures. We suggest an index for soil pore tortuosity, which appears to reflect the pore characteristics of the artificial samples tested. More studies are needed to evaluate the applicability of the index for soil samples.
Soil Science Society of America Journal
A Novel Method for Estimating Soil Precompression Stress from Uniaxial Confined Compression Tests
Mathieu Lamandé, Per Schjønning and Rodrigo Labouriau
The concept of precompression stress is used for estimating soil strength that is relevant to field traffic. It represents the maximum stress experienced by the soil. The most recently developed fitting method to estimate precompression stress (Gompertz) is based on the assumption of an S-shaped stress–strain curve, which is not always fulfilled. A new simple numerical method was developed to estimate precompression stress from stress–strain curves, based solely on the sharp bend on the stress–strain curve partitioning the curve into an elastic and a plastic section. Our study had three objectives: (i) assessing the utility of the numerical method by comparison with the Gompertz method, (ii) comparing the estimated precompression stress to the maximum preload of test samples, and (iii) determining the influence that soil type, bulk density, and soil water potential have on the estimated precompression stress. Stress–strain curves were obtained by performing uniaxial confined compression tests (UCCTs) on undisturbed soil cores for three soil types at three soil water potentials. The new method performed better than the Gompertz fitting method for estimating precompression stress. The values of precompression stress obtained from the new method were linearly related to the maximum stress experienced by the soil samples prior to the UCCT at each soil condition, with a slope close to 1. Precompression stress determined via the new method was not related to soil type or dry bulk density. This might because the range for both parameters was too small but it may also emphasize the complex effect of soil structure on soil mechanical strength.
Soil Science Society of America Journal
Methods for Improvement of the Ecosystem Services of Soil by Sustainable Land Management in the Myjava River Basin.
Korbeľová, Lenka, and Silvia Kohnová.
The main aim of this study is the development of methods for the assessment of the ecosystem services (ESS) of soils within the RECARE project and the participatory identification of measures to combat soil threats caused by floods in the Myjava River basin. The Myjava Hills highlands are known for their rapid runoff response and related muddy floods, which are determined by both the natural and socio-economic conditions. Within the frame of the mentioned project, the ESS framework with detailed relationships between the ecology, societal response, driving forces and also human well-being was identified. Next, to assess the SLM practices in the pilot basin, the stakeholders, who showed an interest in solving the flood protection problems in their areas, took an active part in the process of evaluating, scoring and selecting the best sustainable land management practices (SLM) for the flood protection of soil. From the results which were proposed, the technology of vegetative strips was top rated within the total results among all the SLM measures in all the categories, followed by water-retaining ditches and small wooden dams. Building a polder least meets the proposed SLM criteria.
Slovak Journal of Civil Engineering 25, no. 1, (2017), 29-36.
Challenges of conservation agriculture practices on silty soils. Effects on soil pore and gas transport characteristics in North-eastern Italy
Piccoli, I., P. Schjønning, M. Lamandé, L. Furlan, and F. Morari.
Soil air exchange is one of the most important soil functions that directly impacts on crop productivity and environment. Generally, conservation agriculture (CA) practices are expected to provide improved soil aeration but contrasting texture-related effects were found in the literature. The aim of this study was to evaluate the effect of CA practices on gas transport characteristics in the silty soils of the Veneto Region (North-Eastern Italy). In 2010, a field experiment comparing CA practices (no-tillage, cover crop and residues retention) to conventional intensive tillage (IT) system was established in four farms located in the Veneto low plain. In fall 2015, 144 undisturbed 100 cm3 soil cores where collected at two different layers (3–6.5 cm and 20–23.5 cm) and analysed for air-filled porosity, air permeability, gas diffusivity and soil structure indices derived.
Gas transport measurements highlighted low transmission properties of the silty soils independently from agronomic management. Both air permeability and relative gas diffusivity showed poor aerated conditions being generally <20 μm2 and <0.005, respectively.
CA treatments affected the transmission properties only in the coarsest soil studied causing a reduction of air permeability in the deeper layer and relative gas diffusivity in both layers. The CA-induced reduction was related to the tillage effect on soil bulk density and suggested that CA not only affected the air-filled porosity but also continuity and tortuosity characteristics.
The poor structural stability of Veneto soils, particularly the poor soil organic carbon content, could prevent the exploitation of CA practices firstly on soil structure and in turn on gas exchanges. For these reasons further studies elucidating the mechanisms improving soil structural conditions for silty soils as those examined in this study are required.
Published in: Soil and Tillage Research 172 (2017): 12-21.
Rainfall simulation and Structure-from-Motion photogrammetry for the analysis of soil water erosion in Mediterranean vineyards.
Prosdocimi M, Burguet M, Di Prima S, Sofia G, Terol Esparza E, Rodrigo Comino J, Cerdà A, Tarolli P.
Soil water erosion is a serious problem, especially in agricultural lands. Among these, vineyards deserve attention, because they constitute for the Mediterranean areas a type of land use affected by high soil losses. A significant problem related to the study of soil water erosion in these areas consists in the lack of a standardized procedure of collecting data and reporting results, mainly due to a variability among the measurement methods applied. Given this issue and the seriousness of soil water erosion in Mediterranean vineyards, this works aims to quantify the soil losses caused by simulated rainstorms, and compare them with each other depending on two different methodologies: (i) rainfall simulation and (ii) surface elevation change-based, relying on high-resolution Digital Elevation Models (DEMs) derived from a photogrammetric technique (Structure-from-Motion or SfM). The experiments were carried out in a typical Mediterranean vineyard, located in eastern Spain, at very fine scales. SfM data were obtained from one reflex camera and a smartphone built-in camera. An index of sediment connectivity was also applied to evaluate the potential effect of connectivity within the plots. DEMs derived from the smartphone and the reflex camera were comparable with each other in terms of accuracy and capability of estimating soil loss. Furthermore, soil loss estimated with the surface elevation change-based method resulted to be of the same order of magnitude of that one obtained with rainfall simulation, as long as the sediment connectivity within the plot was considered. High-resolution topography derived from SfM revealed to be essential in the sediment connectivity analysis and, therefore, in the estimation of eroded materials, when comparing them to those derived from the rainfall simulation methodology. The fact that smartphones built-in cameras could produce as much satisfying results as those derived from reflex cameras is a high value added for using SfM.
Published in Science of the Total Environment, 2017, 574, 204-215.
Upper subsoil pore characteristics and functions as affected by field traffic and freeze–thaw and dry–wet treatments
Per Schjønning, Per, Mathieu Lamandé, Valentin Crétin, and Janne Aalborg Nielsen.
Cultivated soils are subject to very high stresses from machinery. This may affect the soil pore system and its processes, soil functions and soil ecosystem services. Compaction experiments were performed on loamy Luvisols at three sites in Denmark: Aarslev, Flakkebjerg and Taastrup. Non-trafficked control soil was compared with soil subjected to four annual traffic events with approximately 3-, 6- or 8-Mg wheel loads from tractor–trailer combinations. A self-propelled machine with a single pass of approximately 12-Mg wheel load was tested at Aarslev. Undisturbed soil cores were sampled at 0.3m depth when the experimental plots had received either 2 years (Flakkebjerg) or 3 years (Aarslev and Taastrup) of repeated compaction treatment. The volume of air-filled pores and air permeability were quantified for soil drained to –100 hPa matric potential. Freeze–thaw and dry–wet treatments were applied to soil cores in the laboratory for Aarslev and Taastrup samples. The multipass machinery significantly affected >30 mm soil pores and air permeability at wheel loads of ~6 Mg or higher, whereas no or only minor effects could be detected for ~3-Mg wheel loads. Indices combining air permeabilities with air-filled porosities indicated that pore morphological features had also been affected. Estimates of hydraulic conductivity indicated critical conditions for the percolation of excess rainwater for severely compacted soil at Aarslev. Generally, the single-pass machine with a high wheel load did not affect the pores and their function. A dry–wet event was a more effective remediation of compaction than a freeze–thaw treatment. In conclusion, present-day field traffic risks creating a bottleneck soil layer for important soil functions just below the tilled topsoil.
Published in Soil Research, 2017
Reviewed articles 2016
Assessing soil salinity using WorldView-2 multispectral images in Timpaki, Crete, Greece
D. D. Alexakis, I. N. Daliakopoulos, I. S. Panagea & I. K. Tsanis
Salinization is one of the major soil degradation threats occurring worldwide. This study evaluates the feasibility of operational surface soil salinity mapping based on state-of-the-art Earth Observation (EO) products captured by sensors on-board WorldView-2 (WV2) and Landsat 8 satellites. The proposed methods are tested in Timpaki, south-central Crete,Greece, where brackish water irrigation puts soil health at risk of soil salinization. In all cases, EO products are calibrated against soil samples collected from bare soil locations. Results indicate a moderate correlation of observed ECe values with the investigated remote sensing parameters. Regarding sensitivity to saline soil, the yellow band displays higher values. Comparison between methods used in the literature shows that those developed specifically for soil salinity, and especially index S5, perform better. The proposed ‘detection index’ and 3D PCA transformation methodology perform reasonably well in detecting areas with high ECe values and provide a simple and effective operational alternative for saline topsoil detection and mapping.
Published in Geocarto International
Mulching practices for reducing soil water erosion: A review
Prosdocimi, M., Tarolli, P., Cerdà, A.
Among the soil conservation practices that are used, mulching has been successfully applied to reduce soil and water losses in different contexts, such as agricultural lands, fire-affected areas, rangelands and anthropic sites. In these contexts, soil erosion by water is a serious problem, especially in semi-arid and semi-humid areas of the world. Although the beneficial effects of mulching are known, further research is needed to quantify them, especially in areas where soil erosion by water represents a severe threat. In the literature, there are still some uncertainties about how to maximize the effectiveness of mulching to reduce the soil and water loss rates. Given the seriousness of soil erosion by water and the uncertainties that are still associated with the correct use of mulching, this study review aims to (i) develop a documented and global database on the use of mulching with vegetative residues; (ii) quantify the effects of mulching on soil and water losses based on different measurement methods and, consequently, different spatial scales; (iii) evaluate the effects of different types of mulches on soil and water losses based on different measurement methods; and (iv) provide suggestions for more sustainable soil management. The data published in the literature have been collected. The results showed the beneficial effects of mulching in combating soil erosion by water in all of the environments considered here, with reduction rates in the average sediment concentration, soil loss and runoff volume that, in some cases, exceeded 90%. However, the economic feasibility of mulching application was not readily available in the literature. Therefore, more research should be performed to help both farmers and land managers by providing them with evidence-based means for implementing more sustainable soil management practices.
Published in Earth-Science Reviews, 2016, 161: 191–203.
The use of barley straw residues to avoid high erosion and runoff rates on persimmon plantations in Eastern Spain under low frequency – high magnitude simulated rainfall events
Cerdà, A., González-Pelayo, O., Giménez-Morera, A., Jordán, A., Pereira, P., Novara, A., Brevik, E.C., Prosdocimi, M., Mahmoodabadi, M., Keesstra, S., García Orenes, F., Ritsema, C., .
Soil and water losses due to agricultural mismanagement are high and non-sustainable in many orchards. An experiment was set up with rainfall simulation at 78 mm h–1 over 1 hour on 20 paired plots of 2 m2 (bare and straw covered) in new persimmon plantations in Eastern Spain. Effects of straw cover on the control of soil and water losses were assessed. An addition of 60% straw cover (75 g m–2) resulted in delayed ponding and runoff generation and consequently reduced water losses from 60% to 13% of total rainfall. The straw cover reduced raindrop impact and thus sediment detachment from 1014 to 47 g plot–1 h–1. The erosion rate was reduced from 5.1 to 0.2 Mg ha–1 h–1. The straw mulch was found to be extremely efficient in reducing soil erosion rates.
Published in Soil Res, 2016, 54, 2, 154-165
Effects of Soil Management Techniques on Soil Water Erosion in Apricot Orchards.
Keesstra, S., P. Pereira, A. Novara, E. C. Brevik, C. Azorin-Molina, L. Parras-Alcántara, A. Jordán, and A. Cerdà.
Soil erosion is extreme in Mediterranean orchards due to management impact, high rainfall intensities, steep slopes and erodible parent material. Vall d'Albaida is a traditional fruit production area which, due to the Mediterranean climate and marly soils, produces sweet fruits. However, these highly productive soils are left bare under the prevailing land management and marly soils are vulnerable to soil water erosion when left bare. In this paper we study the impact of different agricultural land management strategies on soil properties (bulk density, soil organic matter, soil moisture), soil water erosion and runoff, by means of simulated rainfall experiments and soil analyses. Three representative land managements (tillage/herbicide/covered with vegetation) were selected, where 20 paired plots (60 plots) were established to determine soil losses and runoff. The simulated rainfall was carried out at 55 mm h− 1 in the summer of 2013 (< 8% soil moisture) for one hour on 0.25 m2 circular plots. The results showed that vegetation cover, soil moisture and organic matter were significantly higher in covered plots than in tilled and herbicide treated plots. However, runoff coefficient, total runoff, sediment yield and soil erosion were significantly higher in herbicide treated plots compared to the others. Runoff sediment concentration was significantly higher in tilled plots. The lowest values were identified in covered plots. Overall, tillage, but especially herbicide treatment, decreased vegetation cover, soil moisture, soil organic matter, and increased bulk density, runoff coefficient, total runoff, sediment yield and soil erosion. Soil erosion was extremely high in herbicide plots with 0.91 Mg ha− 1 h− 1 of soil lost; in the tilled fields erosion rates were lower with 0.51 Mg ha− 1 h− 1. Covered soil showed an erosion rate of 0.02 Mg ha− 1 h− 1. These results showed that agricultural management influenced water and sediment dynamics and that tillage and herbicide treatment should be avoided.
Published in Science of the Total Environment, 2016. 551-552: 357-366.
Soil precompression stress, penetration resistance and crop yields in relation to differently-trafficked, temperate-region sandy loam soils.
Per Schjønning, Mathieu Lamandé, Lars J. Munkholm, Henning S. Lyngvig, and Janne Aa Nielsen.
Compaction of the subsoil due to heavy traffic in moist and wet soil is widespread in modern agriculture. The objective of this study was to quantify the effects from realistic field traffic on soil penetration resistance and barley crop yield for three Luvisols developed from glacial till. Undisturbed soil cores were used for quantifying the precompression stress (Ͽpc) of non-compacted soil. Tractor-trailer combinations for slurry application with wheel loads of 3, 6 and 8 Mg (treatments M3, M6, M8) were used for the experimental traffic in the spring at field-capacity. For one additional treatment (labelled M8-1), the soil was loaded only in the first year. A tricycle-like machine with a single pass of wide tyres each carrying 12 Mg (treatment S12) was included at one site. Traffic treatments were applied in a randomized block design with four replicates and with treatments repeated in four consecutive years (20102013). After two years of repeated experimental traffic, penetration resistance (PR) was measured to a depth of 1 m. The yield of a spring barley crop (Hordeum vulgare L.) was recorded in all four years of the experiment. The results did not support our hypothesis of Ͽpc as a soil strength measure predicting resistance to subsoil compaction. The tyre inflation pressure and/or the mean ground pressure were the main predictors of PR in the upper soil layers. For deeper soil layers, PR correlated better to the wheel load. The number of wheel passes (M-treatments vs the S12 treatment) modified this general pattern, indicating a very strong impact of repeated wheel passes. Our data indicate that a single traffic event may mechanically weaken the soil without inducing major compaction but with influence on the effect of subsequent traffic even after as long an interval as a year (treatments M8 vs M8-1). Crop yields were much influenced by compaction of the plough layer. Due to the repeated wheel passes for the M-treatments, significant yield penalties were observed, while the single-pass treatment with 12 Mg wheel load in S12 did not have significant effects on crop yield. Our hypothesis of 3 Mg wheel load as an upper threshold for not inducing subsoil compaction was confirmed for the tractor-trailer treatments with repeated wheel passes but not supported for the single-pass machinery. The results call for further studies of the potential for carrying high loads using wide, low-pressure tyres by crab steering/dog-walk machinery.
Published in: Soil and Tillage Research 163 (2016): 298-308.
Quantitative Comparison of Initial Soil Erosion Processes and Runoff Generation in Spanish and German Vineyards.
Rodrigo Comino, J., T. Iserloh, T. Lassu, A. Cerdà, S. D. Keesstra, M. Prosdocimi, C. Brings, et al.
The aim of this study was to enable a quantitative comparison of initial soil erosion processes in European vineyards using the same methodology and equipment. The study was conducted in four viticultural areas with different characteristics (Valencia and Málaga in Spain, Ruwer-Mosel valley and Saar-Mosel valley in Germany). Old and young vineyards, with conventional and ecological planting and management systems were compared. The same portable rainfall simulator with identical rainfall intensity (40 mm h− 1) and sampling intervals (30 min of test duration, collecting the samples at 5-min-intervals) was used over a circular test plot with 0.28 m2.
The results of 83 simulations have been analysed and correlation coefficients were calculated for each study area to identify the relationship between environmental plot characteristics, soil texture, soil erosion, runoff and infiltration.
The results allow for identification of the main factors related to soil properties, topography and management, which control soil erosion processes in vineyards. The most important factors influencing soil erosion and runoff were the vegetation cover for the ecological German vineyards (with 97.6 ± 8% infiltration coefficients) and stone cover, soil moisture and slope steepness for the conventional land uses.
Published in Science of the Total Environment, 2016, 565: 1165-1174.
Soil Erosion Processes in European Vineyards: A Qualitative Comparison of Rainfall Simulation Measurements in Germany, Spain and France
Rodrigo Comino J, Iserloh T, Morvan X, Malam Issa O, Naisse C, Keesstra SD, Cerdà A, Prosdocimi M, Arnáez J, Lasanta T, Ramos MC, Marqués MJ, Ruiz Colmenero M, Bienes R, Ruiz Sinoga JD, Seeger M, Ries JB
Small portable rainfall simulators are considered a useful tool to analyze soil erosion processes in cultivated lands. European research groups in Spain (Valencia, Málaga, Lleida, Madrid and La Rioja), France (Reims) and Germany (Trier) have used different rainfall simulators (varying in drop size distribution and fall velocities, kinetic energy, plot forms and sizes, and field of application) to study soil loss, surface flow, runoff and infiltration coefficients in different experimental plots (Valencia, Montes de Málaga, Penedès, Campo Real and La Rioja in Spain, Champagne in France and Mosel-Ruwer valley in Germany). The measurements and experiments developed by these research teams give an overview of the variety of methodologies used in rainfall simulations to study the problem of soil erosion and describe the erosion features in different climatic environments, management practices and soil types. The aims of this study are: (i) to investigate where, how and why researchers from different wine-growing regions applied rainfall simulations with successful results as a tool to measure soil erosion processes; (ii) to make a qualitative comparison about the general soil erosion processes in European terroirs; (iii) to demonstrate the importance of the development of standard method for measurement of soil erosion processes in vineyards, using rainfall simulators; and (iv) and to analyze the key factors that should be taken into account to carry out rainfall simulations. The rainfall simulations in all cases allowed infiltration capacity, susceptibility of the soil to detachment and generation of sediment loads to runoff to be determined. Despite using small plots, the experiments were useful to analyze the influence of soil cover to reduce soil erosion, to make comparisons between different locations, and to evaluate the influence of different soil characteristics. The comparative analysis of the studies performed in different study areas points out the need to define an operational methodology to carry out rainfall simulations, which allows us to obtain representative and comparable results and to avoid errors in the interpretation in order to achieve comparable information about runoff and soil loss.
Published in Hydrology, 2016, 3 (1), 6; 2016
Community-Based Rehabilitation of Mountain Terraces in Cyprus.
Christos Zoumides, Adriana Bruggeman, Elias Giannakis, Corrado Camera, Hakan Djuma, Marinos Eliades, Katerina Charalambous
Participatory methods and community-based approaches have an important role to play in combating land degradation. This paper follows a well-defined participatory framework to identify key stakeholders and to select Sustainable Land Management approaches for reducing soil erosion and land degradation in the Troodos Mountains of Cyprus. Among the options suggested and evaluated by stakeholders, terrace rehabilitation had the best overall performance, followed by crop diversification and afforestation. Stakeholders agreed that the rehabilitation of dry-stone terraces was the preferred option, as it is a practice with high environmental benefits and fits well in the local socio-cultural context, despite the higher cost compared to other options. In the first year of implementing the approach, three mountain communities co-organised hands-on terrace maintenance events, engaging more than 160 people in rehabilitation activities. The community-based approach has sparked the interest of people within and beyond the research site, and another series of events is scheduled for the coming season. This outcome indicates that social innovations can benefit from the integration of local and scientific knowledge, while participatory process can enhance the self-confidence and organisational structures of local communities. Sustaining and enhancing the impact of the approach in the long-run require developing local terrace maintenance institutions, actively engaging the youth in terrace management and improving the profitability of mountain farming through the differentiation of local products.
Published in Land Degradation & Development (2016) August 1
Operationalizing Ecosystem Services for the Mitigation of Soil Threats: A Proposed Framework /G. Schwilch, L. Bernet, L. Fleskens, E. Giannakis, J. Leventon, T. Marañón, J. Mills, C. Short, J. Stolte, H. van Delden, S. Verzandvoort
Despite numerous research efforts over the last decades, integrating the concept of ecosystem services into land management decision-making continues to pose considerable challenges. Researchers have developed many different frameworks to operationalize the concept, but these are often specific to a certain issue and each has their own definitions and understandings of particular terms. Based on a comprehensive review of the current scientific debate, the EU FP7 project RECARE proposes an adapted framework for soil-related ecosystem services that is suited for practical application in the prevention and remediation of soil degradation across Europe. We have adapted existing frameworks by integrating components from soil science while attempting to introduce a consistent terminology that is understandable to a variety of stakeholders. RECARE aims to assess how soil threats and prevention and remediation measures affect ecosystem services. Changes in the natural capital's properties influence soil processes, which support the provision of ecosystem services. The benefits produced by these ecosystem services are explicitly or implicitly valued by individuals and society. This can influence decision- and policymaking at different scales, potentially leading to a societal response, such as improved land management. The proposed ecosystem services framework will be applied by the RECARE project in a transdisciplinary process. It will assist in singling out the most beneficial land management measures and in identifying trade-offs and win–win situations resulting from and impacted by European policies. The framework thus reflects the specific contributions soils make to ecosystem services and helps reveal changes in ecosystem services caused by soil management and policies impacting on soil. At the same time, the framework is simple and robust enough for practical application in assessing soil threats and their management with stakeholders at various levels.
Published in Ecological Indicators Volume 67, August 2016, Pages 586–597
Combining qualitative and quantitative methods for soil erosion assessments: an application in a sloping mediterranean watershed, Cyprus
Hakan Djuma,Adriana Bruggeman,Corrado Camera,Christos ZoumidesDjuma, H., Bruggeman, A., Camera, C. and Zoumides,
In arid and semi-arid regions, water erosion is difficult to model because of highly irregular precipitation regimes and changes in vegetation cover. The application of quantitative, process-based models at the catchment scale is often problematic because of large data requirements. Qualitative methods require less data and can be more easily performed in a relatively short time, but they are more subjective. The objective of this research is to develop an erosion assessment methodology that combines qualitative field surveys with quantitative model estimates. The qualitative World Overview of Conservation Approaches and Technologies (WOCAT) methodology is based on expert observations per mapping unit, while the Pan-European Soil Erosion Risk Assessment (PESERA) model simulates hill slope soil loss based on land cover, soil texture, meteorological data and slope profile. This study was conducted in the 106·4-km2 Peristerona watershed in Cyprus with a mean local slope higher than 40% in the mountainous upstream area and less than 8% in the plain. Out of 68 units, PESERA and WOCAT results were in agreement in 40 units, while PESERA results were lower in 25 and higher in 3 units. Both methods identified burnt areas and complex cultivation patterns as the most degraded. The total PESERA-based sediment yield for the watershed was 1·2 Mg ha−1 y−1, which fell within the range of the sediment yield measured at the check-dam downstream (0·2–2 Mg ha−1 y−1). This study provides a linkage between qualitative and quantitative soil erosion methods and helps to translate the outcomes of the former into the latter, thus providing a good tool for local erosion assessment.
Published in Land Degradation & Development 11 July (2016)
An applied methodology for stakeholder identification in transdisciplinary research
Julia Leventon, Luuk Fleskens, Heleen Claringbould, Gudrun Schwilch, Rudi Hessel
In this paper we present a novel methodology for identifying stakeholders for the purpose of engaging with them in transdisciplinary, sustainability research projects. In transdisciplinary research, it is important to identify a range of stakeholders prior to the problem-focussed stages of research. Early engagement with diverse stakeholders creates space for them to influence the research process, including problem definition, from the start. However, current stakeholder analysis approaches ignore this initial identification process, or position it within the subsequent content-focussed stages of research. Our methodology was designed as part of a research project into a range of soil threats in seventeen case study locations throughout Europe.Our methodology was designed to be systematic across all sites. It is based on a snowball sampling approach that can be implemented by researchers with no prior experience of stakeholder research, and without requiring significant financial or time resources. It therefore fosters transdisciplinarity by empowering physical scientists to identify stakeholders and understand their roles. We describe the design process and outcomes, and consider their applicability to other research projects. Our methodology therefore consists of a two-phase process of design and implementation of an identification questionnaire. By explicitly including a design phase into the process, it is possible to tailor our methodology to other research projects.
Pulished in Sustainable Science (2016) 11:763–775 (Open Access)
The threat of soil salinity: A European scale review
I.N. Daliakopoulos, I.K. Tsanis, A. Koutroulis, N.N. Kourgialas, A.E. Varouchakis, G.P. Karatzas,
Soil salinisation is one of the major soil degradation threats occurring in Europe. The effects of salinisation can be observed in numerous vital ecological and non-ecological soil functions. Drivers of salinisation can be detected both in the natural and man-made environment, with climate and the foreseen climate change also playing an important role. This review outlines the state of the art concerning drivers and pressures, key indicators as well as monitoring, modeling and mapping methods for soil salinity. Furthermore, an overview of the effect of salinisation on soil functions and the respective mechanism is presented. Finally, the state of salinisation in Europe is presented according to the most recent literature and a synthesis of consistent datasets. We conclude that future research in the field of soil salinisation should be focused on among others carbon dynamics of saline soil, further exploration of remote sensing of soil properties and the harmonization and enrichment of soil salinity maps across Europe within a general context of a soil threat monitoring system to support policies and strategies for the protection of European soils.
Published in Science of the Total Environment
Subsoil compaction assessed by visual evaluation and laboratory methods
Obour, Peter Bilson, Per Schjønning, Yi Peng, and Lars J. Munkholm.
Subsoil compaction is one of the major causes of land degradation worldwide and therefore a major threat to future crop productivity. The objective of this contribution was to evaluate the effects of compaction treatments on soil structure based on the numerical visual evaluation of subsoil structure (SubVESS) method and on quantitative measurements of soil pore characteristics. The effect of soil compaction was evaluated using treatments from a compaction experiment initiated in 2010 at Research Centre Flakkebjerg, Denmark, on a sandy loam soil using five levels of compaction. In this study we used i) non-compacted reference, ii) Treatment M3, where soil was subjected to multiple passes (five wheel passes per compaction event annually) of a tractor-trailer combination with max. wheel load of ∼3 Mg, and iii) M8, with multiple passes (four wheel passes per compaction event annually) of a tractor-trailer combination with max. wheel load of ∼8 Mg. The tire inflation pressure was generally above the recommended pressure in order to mimic the inflation pressures commonly used in practice. The treatments were applied track-by-track in the spring of 2010–2013 when the soil water content was close to field capacity. Spring barley (Hordeum vulgare L.) was established every year after a shallow secondary tillage to ∼0.05 m depth to loosen the uppermost layer. Sampling and field evaluation were done on May 7, 2014, i.e. after four years of compaction treatments (2010–2013) and one year of recovery. The soil profiles were evaluated at the same time as soil cores were sampled at 0.3, 0.5 and 0.7 m depth. In the laboratory, we measured water content, total porosity, air-filled porosity (εa), air permeability (ka) and calculated pore organization indices (PO1 = ka/εa and PO2 = ka/εa2) on the soil cores. We estimated the blocked air-filled porosity and pore continuity index from the relationship between air permeability and air-filled porosity for −30 to −300 hPa matric potentials. Assessment using the SubVESS method showed a marked effect of the M8 treatment on soil structural quality down to ∼0.65 m depth, but the effects of the M3 were not significantly different from the control at any depth. This was confirmed by the laboratory-measured data, which showed that the M8 treatment drastically reduced total porosity, air-filled porosity, air permeability, pore size distribution, pore tortuosity and continuity, especially at 0.3 and 0.5 m depths.
Detailed measurements of the anisotropy of soil pore characteristics at 0.3–0.4 m depth showed that for PO2 (pore size distribution) and blocked air-filled porosity the control soil was significantly anisotropic. Although compaction with the ∼8 Mg wheel load affected the vertically and horizontally-oriented pores differently, it did not significantly affect the anisotropy of the different pore characteristics. Our results showed that in general, there was a good agreement between the field and laboratory methods and thus, the two can be combined to evaluate the effects of compaction in the subsoil.
Published in Soil and Tillage Research (2016).
Modelling soil salinity in greenhouse cultivations under a changing climate with SALTMED: Model modification and application in Timpaki, Crete /Ioannis N. Daliakopoulos, Polixeni Pappa, Manolis G. Grillakis, Emmanouil A. Varouchakis, and Ioannis K. Tsanis
Soil salinity is a major soil degradation threat especially for arid coastal environments where it hinders agricultural production thus imposing a desertification risk. In the prospect of a changing climate, soil salinity due to brackish water irrigation introduces additional uncertainties regarding the viability of deficit irrigation and intensive cultivation practices such as greenhouse cropping. Here we propose a modification of the SALTMED leaching requirements model to account for greenhouse cultivation conditions. The model is applied in the RECARE Project Case Study of Timpaki, a semi-arid region in south-central Crete (Greece) where greenhouse horticulture is an important land use. Excessive groundwater abstractions towards irrigation have resulted in a drop of the groundwater level in the coastal part of the aquifer, thus leading to seawater intrusion and in turn to soil salinisation. Crop yield and soil profile Electrical Conductivity (EC) sensitivity to initial soil EC (up to 2 dS m-1) and irrigation water EC (up to 3 dS m-1) are modelled for the locally popular horticultural crops of Solanum lycopersicum, Solanum melongena and Capsicum annuum. Climate model data obtained from 9 General Circulation Models (GCMs) for the “worst case” Representative Concentration Pathway of 8.5 W m-2 of the 5th phase of the Coupled Model Intercomparison Project are corrected for bias against historical observations with the Multisegment Statistical Bias Correction method and used to estimate crop yield and soil profile Electrical Conductivity (??) sensitivity in a warmer future. Results show that the effects of climate change on Solanum lycopersicum greenhouse cultivations 28 of Timpaki will be detrimental while Solanum melongena and Capsicum annuum cultivations may show greater resilience.
Published in: Soil Science Volume 181 - Issue 6 - p 241–251
Nano to macro pore structure changes induced by long-term residue management in three different soils /Chiara Pituello, Nicola Dal Ferro, Gianluca Simonetti, Antonio Berti, Francesco Morari
The use of crop residues for bioenergy production has gathered much attention in recent years. For this reason, the potential detrimental effects on soil quality caused by their removal need to be carefully evaluated before this practice becomes widely used.
Data from a long-term field experiment on residue management in three contrasting soils (clay, sandy-loam and sandy) were analysed in order to understand crop residue effects on soil organic carbon stocks. In addition, since soil structure is known to be a sensitive descriptor of soil quality, different techniques were combined to investigate a wide range of pore sizes (from 0.25 nm to 2.5 mm) and pore morphology.
Forty-three years of crop residue incorporation led to a significant increase in the organic carbon content of the three soils. The clay and sandy-loam soils were the most effective in retaining organic carbon as they exhibited the highest absolute increases. The sandy soil showed a residue-induced increase in organic carbon content, indicating that some protection mechanisms may act in the long term even in soils with a scarce ability to protect organic carbon from degradation.
Residues modified the soil structure, inducing an increase in total pore volume as measured by the core method, although their effect was not found in all pore size classes. Residues decreased mesoporosity (30–75 μm), while their effect on macropores (>75 μm) was in terms of shape, increasing the irregular and elongated pores rather than their size frequency. The results thus showed a limited overall effect of residues on soil structure. However, even minor pore network changes could affect other important soil properties such as water movement, solute transport and gas exchanges.
Published in: Agriculture, Ecosystems and Environment, Vol 217, 1 February 2016, Pages 49–58
River banks and channels as hotspots of soil pollution after large-scale remediation of a river basin /M.T. Domínguez,J.M. Alegre, P. Madejón, E. Madejón, P. Burgos, F. Cabrera, T. Marañón, J.M. Murillo
Riparian areas are highly dynamic systems where the control of soil pollution might be particularly challenging. Limited accessibility to river banks and bed sediments makes reclamation operations particularly difficult in these topographical positions, in comparison to floodplains. This usually leads to the large-scale spread of pollutants following pollution episodes in riparian areas. Here, we aimed to evaluate the persistence of trace-element pollution in the soils of Guadiamar River Valley (SW Spain), a large-scale remediation after a mine-spill. We monitored topsoil along the river basin, and in different topographical positions across the river section (river channel, river banks and floodplain), 16 years after a pollution episode and subsequent remediation program. River channels and banks were identified as hotspots of soil pollution, where soluble concentrations of As, Cd and Zn were significantly higher than in floodplains. Along the basin, soil pH and carbonate content was highly variable as a result of contrasted geological background, differential loads of sulfide deposition after the accident and irregular effectiveness of the applied amendments. Cadmium and Zn showed the highest levels of long-term re-distribution from the pollution source. The results suggests that the stabilization and remediation of soil pollution in river banks and channels, often overlooked when achieving remediation works, should be a priority for land managers.
Published in: Geoderma Vol 261, 1 January 2016, Pages 133–140
Evaluation of soil salinity amelioration technologies in Timpaki, Crete: a participatory approach /I. S. Panagea, I. N. Daliakopoulos, I. K. Tsanis, and G. Schwilch
Soil salinity management can be complex, expensive, and time demanding, especially in arid and semi-arid regions. Besides taking no action, possible management strategies include amelioration and adaptation measures. Here we apply the World Overview of Conservation Approaches and Technologies (WOCAT) framework for the systematic analysis and evaluation and selection of soil salinisation amelioration technologies in close collaboration with stakeholders. The participatory approach is applied in the RECARE (Preventing and Remediating degradation of soils in Europe through Land Care) project case study of Timpaki, a semi-arid region in south-central Crete (Greece) where the main land use is horticulture in greenhouses irrigated by groundwater. Excessive groundwater abstractions have resulted in a drop of the groundwater level in the coastal part of the aquifer, thus leading to seawater intrusion and in turn to soil salinisation. The documented technologies are evaluated for their impacts on ecosystem services, cost, and input requirements using a participatory approach and field evaluations. Results show that technologies which promote maintaining existing crop types while enhancing productivity and decreasing soil salinity are preferred by the stakeholders. The evaluation concludes that rainwater harvesting is the optimal solution for direct soil salinity mitigation, as it addresses a wider range of ecosystem and human well-being benefits. Nevertheless, this merit is offset by poor financial motivation making agronomic measures more attractive to users.
Published in: Solid Earth, 7, 177-190,
Short-time phosphorus losses by overland flow in burnt pine and eucalypt plantations in north-central Portugal: A study at micro-plot scale Ferreira R.V., Serpa D., Cerqueira M.A., Keizer J.J.,
Over the past decades, wildfires have affected vast areas of Mediterranean ecosystems leading to a variety of negative on- and off-site environmental impacts. Research on fire-affected areas has given more attention to sediment losses by fire-enhanced overland flow than to nutrient exports, especially in the Mediterranean region. To address this knowledge gap for post-fire losses of phosphorus (P) by overland flow, a recently burnt forest area in north-central Portugal was selected and instrumented immediately after a wildfire. Three slopes were selected for their contrasting forest types (eucalypt vs. pine) and parent materials (granite vs. schist). The selected study sites were a eucalypt site on granite (BEG), a eucalypt site on schist (BES) and a maritime pine site on schist (BPS). Micro-plots were monitored over a period of six months, i.e. till the construction of terraces for reforestation obliged to the removal of the plots. During this 6-month period, overland flow samples were collected at 1- to 2-weekly intervals, depending on rainfall. Total P and PO4-P losses differed markedly between the two types of forests on schist, being lower at the pine site than at the eucalypt site, probably due to the presence of a protective layer of pine needle cast. Parent material did not play an important role in PO4-P losses by overland flow but it did in TP losses, with significantly lower values at the eucalypt site on granite than that on schist. These differences in TP losses can be attributed to the coarser texture of granite soils, typically promoting infiltration and decreasing runoff. The present findings provided further insights into the spatial and temporal patterns of post-fire soil nutrient losses in fire-prone forest types during the initial stages of the window-of-disturbance, which can be useful for defining post-fire emergency measures to reduce the risk of soil fertility losses.
Published in: Science of the Total Environment 551–552, 631–639
Major and trace elements in soils and ashes of eucalypt and pine forest plantations in Portugal following a wildfire / Campos I., Abrantes N., Keizer J.J., Vale C., Pereira P.
Wildfires can play an important role in the environmental distribution of major and trace elements, including through their mobilization by fire-induced runoff and associated transport of soil and ash particles. In particular, fire-induced inputs of these elements into the environment are relevant due to their toxicity and environmental persistence. This study aimed to evaluate the role of wildfire and time-since-fire on the redistribution of major and trace elements, which is a topic poorly documented. To this end, levels of V, Mn, Co, Ni, Cu, Cd and Pb were assessed in soil and ash samples collected immediately following a wildfire in north-central Portugal as well as 4 (after the first post-fire rainfall events), 8 and 15months later. The role of forest type was determined by sampling burnt eucalypt and pine plantations. The main findings of this study were the following: (1) levels of V, Mn, Ni, Cd and Pb were consistently higher in the burnt than unburnt soils, while levels of Co and Cu revealed no differences; (2) time-since-fire affected major and trace elements in three different ways: concentrations of Mn and Cd declined abruptly after the first rainfall events while levels of V, Co and Ni increased during the first 8months and levels of Cu and Pb hardly changed during the study period; (3) all studied elements revealed peak concentrations in the ashes immediately after the fire, which then declined sharply four months later; (4) levels of Co and Ni soils and ashes were higher at the pine plantations than at the eucalypt plantations. This study highlighted the role of wildfire in enhancing levels of major and trace elements in ashes and topsoil of forest plantations and their mobilization within the first year after fire, pointing towards recently burnt forest areas as a potential source of environmental contamination.
Published in:Science of the Total Environment 2016 Dec 1;572:1363-1376
Combining digital soil mapping and hydrological modeling in a data scarce watershed in north-central Portugal /Tavares Wahren F., Julich S., Nunes J.P., Gonzalez-Pelayo O., Hawtree D., Feger K.-H., Keizer J.J.
Data scarcity represents a serious limitation to the use of hydrologic models for supporting decision making processes, and may lead to inappropriate measures for integrated water resources management efforts. In particular, the importance of spatially distributed soil information is often overlooked. The forest-dominated Águeda catchment in north-central Portugal is an example of a region with serious soil data availability limitations. The Soil Land Inference Model (SoLIM) approach, combined with information from several soil surveys, was used to create a map of soil properties based upon the effective soil depths of the landscape. The modified soil map provided a better representation of the soil spatial attributes, particularly the distribution of soil water content. The Soil Water Assessment Tool (SWAT) was applied to the Águeda catchment with two input data sets differing in the soil data. Although SWAT performed satisfactorily in simulating daily streamflow for both data sets at the outlet, results of our study indicate that the SoLIM derived soil data set provides a better representation of the first peak flow events after the dry period. Additionally, it is shown that the better representation of profile depth can contribute considerably to the understanding of water balance components at the small scale and for the implications for management. This study underlines the importance of spatially distributed soil information in watershed modeling for decision making in the river basin management process
Published in: GEODERMA 264, part B, 350- 362
Reviewed articles 2015
Possibilities of estimating the gully erosion changes on the Myjava Basin /Michaela Danáčová, Radovan Nosko, Roman Výleta, Beata Randusová, Ján Szolgay
cooperative fields have contributed to changes in the current landscape of the Myjava river basin. Due to these changes the Myjava Hill land has extraordinarily appropriate conditions for the formation of quick runoff processes, intensive soil erosion and related muddy floods. When muddy floods occur water is flowing from agricultural fields and carrying large quantities of soil. Negative effect of muddy floods is an accumulation of eroded material on roads, in river channels or water reservoirs. Intensive erosion activity of concentrated runoff on slopes creates suitable conditions for formation of permanent and preliminary gullies. The paper presents a possibility to estimate development of rill erosion on the example of selected permanent gully in the locality of Turá Lúka. Development of the gully and its changes over time were evaluated on the basis of historical and orto photo maps. An emphasis has been put on the changes in the length, area and the position of the gully in different periods.
Published in: ACTA HYDROLOGICA SLOVACA Ročník 16, Tematické číslo 1, 2015, 167 - 175
Changes in soil microbial activity and physiochemical properties in agricultural soils in Eastern Spain /Alicia Morugán-Coronado, Fuensanta García-Orenes, Artemi Cerdà
Agricultural land management greatly affects soil properties. Microbial soil communities are the most sensitive and rapid indicators of perturbations in land use and soil enzyme activities are sensitive biological indicators of the effects of soil management practices. Citrus orchards frequently have degraded soils and this paper evaluates how land management in citrus orchards can improve soil quality. A field experiment was performed in an orchard of orange trees (Citrus Sinensis) in the Alcoleja Experimental Station (Eastern Spain) with clay-loam agricultural soils to assess the long-term effects of herbicides with inorganic fertilizers (H), intensive ploughing and inorganic fertilizers (P) and organic farming (O) on the soil microbial properties, and to study the relationship between them. Nine soil samples were taken from each agricultural management plot. In all the samples physicochemical parameters, basal soil respiration, soil microbial biomass carbon, microbial indexes (BSR/C, Cmic/C and BSR/Cmic) and enzymatic activities (urease, dehydrogenase, ß-glucosidase and acid phosphatase) were determined. The results showed significant differences between the different agricultural management practices for the microbial properties and soil microbial indexes, since these were strongly associated with the soil organic matter content. Unlike herbicide use and intensive ploughing - management practices that both showed similar microbial soil properties - the organic management practices contributed to an increase in the soil biology quality, aggregate stability and organic matter content.
Published in Spanish Journal of Soil Science Vol 5, No. 3
Facilitating the afforestation of Mediterranean polluted soils by nurse shrubs. /María T. Domínguez, , Ignacio M. Pérez-Ramos, José M. Murillo, Teodoro Marañón
The revegetation of polluted sites and abandoned agricultural soils is critical to reduce soil losses and to control the spread of soil pollution in the Mediterranean region, which is currently exposed to the greatest soil erosion risk in Europe. However, events of massive plant mortality usually occur during the first years after planting, mainly due to the adverse conditions of high irradiance and drought stress. Here, we evaluated the usefulness of considering the positive plant–plant interactions (facilitation effect) in the afforestation of polluted agricultural sites, using pre-existing shrubs as nurse plants. We used nurse shrubs as planting microsites for acorns of Quercus ilex (Holm oak) along a gradient of soil pollution in southwestern Spain, and monitored seedling growth, survival, and chemical composition during three consecutive years. Seedling survival greatly increased (from 20% to more than 50%) when acorns were sown under shrub, in comparison to the open, unprotected matrix. Facilitation of seedling growth by shrubs increased along the gradient of soil pollution, in agreement with the stress gradient hypothesis that predicts higher intensity of the facilitation effects with increasing abiotic stress. Although the accumulation of trace elements in seedling leaves was higher underneath shrub, the shading conditions provided by the shrub canopy allowed seedlings to cope with the toxicity provoked by the concurrence of low pH and high trace element concentrations in the most polluted sites. Our results show that the use of shrubs as nurse plants is a promising tool for the cost-effective afforestation of polluted lands under Mediterranean conditions.
Published in: Journal of Environmental Management Vol Volume 161, 15 September 2015, Pages 276–286
Within-in flume sediment deposition in a forested catchment following wildfire and post-fire bench terracing, north-central Portugal / J.J. Keizer, M.A.S. Martins, S.A. Prats, S.R. Faria, O. González-Pelayo, A.I. Machado, M.E. Rial-Rivas, L.F. Santos, D. Serpa, M.E.T. Varela
Wildfires increase plot-scale soil erosion rates across the world. However, very few studies have monitored post-fire erosion losses at the catchment scale, especially in the Mediterranean region. The FIRECNUTS project was originally set out to address this research gap by selecting a recently burnt catchment and instrumenting its outlet with two flumes with maximum discharge capacities of 120 and 1700 l s-1. Six months after the fire, however, this experimental catchment was bench terraced by bulldozer. Furthermore, the smallest flume suffered from regular deposition of sediments from the onset of its construction. This study was therefore an attempt to explore whether quantifying this deposition of sediments could provide further insight into the sediment yield of a recently burnt and terraced catchment. To this end, the deposited sediments were removed and weighted on a total of 101 occasions during a three year period. The results revealed that: (i) the amounts of sediment deposited over the three hydrological years corresponded to relatively small erosion rates, varying between 0.030 and 0.046 Mg ha-1 yr-1; (ii) while bench terracing is generally viewed as a soil and water conservation technique, it did not produce a clear decrease in sediment deposition, as deposition per mm of streamflow was the same before and after terracing (0.8 kg mm-1); (iii) daily sediment deposition could be explained reasonably well by daily rainfall volume and maximum daily streamflow volume.
Published in: Cuadernos de Investigación Geográfica Vol 41, No. 1
Cation export by overland flow in a recently burnt forest area in north-central Portugal /A.I. Machadoa, D. Serpaa, R.V. Ferreiraa, M.L. Rodríguez-Blancob, R. Pintoa, M.I. Nunesa, M.A. Cerqueiraa, J.J. Keizera
The current fire regime in the Mediterranean Basin constitutes a serious threat to natural ecosystems because it drastically enhances surface runoff and soil erosion in the affected areas. Besides soil particles themselves, soil cations can be lost by fire-enhanced overland flow, increasing the risk of fertility loss of the typically shallow and nutrient poor Mediterranean soils. Although the importance of cations for land-use sustainability is widely recognized, cation losses by post-fire runoff have received little research attention. The present study aimed to address this research gap by assessing total exports of Na+, K+, Ca2 + and Mg2 + in a recently burnt forest area in north-central Portugal. These exports were compared for two types of planted forest (eucalypt vs. maritime pine plantations), two types of parent materials (schist vs. granite) and for two spatial scales (micro-plot vs. hill slope). The study sites were a eucalypt plantation on granite (BEG), a eucalypt plantation on schist (BES) and a maritime pine plantation on schist (BPS). Overland flow samples were collected during the first six months after the wildfire. Cation losses differed strikingly between the two forest types on schist, being higher at the eucalypt than pine site. This difference was evident at both spatial scales, and probably due to the extensive cover of a needle cast from the scorched pine crowns. The role of parent material in cation export was less straightforward as it varied with spatial scale. Cation losses were higher for the eucalypt plantation on schist than for that on granite at the micro-plot scale, whereas the reverse was observed at the hill slope scale. Finally, cation yields were higher at the micro-plot than slope scale, in agreement with the general notion of scaling-effect in runoff generation.
Published in: Science of the Total Environment Volumes 524–525, 15 August 2015, Pages 201–212
Conversion Between Soil Texture Classification Systems Using the Random Forest Algorithm, Air, Soil and Water Research /Čistý, M., Čelár, Ľ., Minarič, P.
This study focuses on the reclassification of a soil texture system following a hybrid approach in which the conventional particle-size distribution (PSD) models are coupled with a random forest (RF) algorithm for achieving more generally applicable and precise outputs. The existing parametric PSD models that could be used for this purpose have various limitations; different models frequently show unequal degrees of precision in different soils or under different environments. The authors present in this article a novel ensemble modeling approach in which the existing PSD models are used as ensemble members. An improvement in precision was proved by better statistical indicators for the results obtained, and the article documents that the ensemble model worked better than any of its constituents (different existing parametric PSD models). This study is verified by using a soil dataset from Slovakia, which was originally labeled by a national texture classification system, which was then transformed to the USDA soil classification system. However, the methodology proposed could be used more generally, and the information provided is also applicable when dealing with the soil texture classification systems used in other countries.
Published in: Air, Soil and Water Research, Volume 8, Pages 67-75, ISSN 1178-6221,
Evaluating Soil Threats Under Climate Change Scenarios in the Andalusia Region, Southern Spain /María Anaya-Romero,Sameh Kotb Abd-Elmabod, Miriam Muñoz-Rojas, Gianni Castellano, Carlos Juan Ceacero, Susana Alvarez, Miguel Méndez, Diego De la Rosa
European policies can be relevant to protect soils under climate change scenarios and therefore preserve the wide variety of functions and services provided by the soil. The European Thematic Strategy for Soil Protection will require member states to identify areas under risk from various soil threats and establish procedures to achieve sustainability. Five models Terraza, Cervatana, Sierra, Raizal, and Pantanal included in the Mediterranean Land Evaluation Information System decision support system packages were used to identify areas vulnerable to various soil threats under climate change scenarios in the Andalusia region. While Terraza and Cervatana forecast general land use capability for a broad series of possible agricultural uses, the Sierra model predicts forestry land suitability for the presence/absence of 22 typical Mediterranean forest species. Raizal and Pantanal models predict soil erosion vulnerability, contamination, and other processes. Interpretation of results in different scenarios allows quantifying the effects of climate change in terms of agricultural productivity, forestry land suitability, erosion, and contamination risks. The obtained results allow to identify detailed vulnerable areas and formulate site-specific management plans for soil protection. Climate change is expected to impact crop growth with a higher impact on summer crops (corn, sunflower, and cotton). The results show a potential opportunity for reforestation (Quercus spp.) in future climate scenarios, while other species such as Castanea sativa will not be suitable in the study area by 2070 and 2100. Soil contamination and erosion show only slight differences between the current and future scenario of climate change.
Published in: Land Degradation & Development Volume 26, Issue 5 July 2015 Pages 441–449
RECARE partner /
|Partner #||Book Chapter Title||Book Title|| |
Reference or DOI
|1||Per Schjønning et al|| |
Aarhus Universitet (AU)
|3||Driver-Pressure-State-Impact-Response (DPSIR) Analysis and Risk Assessment for Soil Compaction - A European Perspective||Advances in Agronomy Vol 133|| |
|2||SAndra Naumann et al||Ecologic Institute||Land take and soil sealing – drivers, trends and policy (legal) instruments: insights from European cities||International Year Book on Soil Law and Policy|