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Soil fertility of cropland depended partly on the local availability of livestock manure in history. The relationship between soil fertility and livestock density became entangled through spatial decoupling of livestock and crop farms. Understanding this relationship is important for spatial planning of livestock farms and for manure management. This paper addresses the relationships between livestock density and soil phosphorus content at farm and regional levels in Hebei (CN), which experienced a very rapid livestock revolution. County-level relationships were explored using existing databases with livestock density and Olsen-P contents. Farm level relationships were explored with a farm survey among 80 livestock farms and 480 crop farms, and with analyses of total phosphorus (TP) and oxalate-extractable phosphorus (Pox) in topsoil (0–15 cm) and subsoil (15–30 cm) of 562 fields. Results indicate that mean Olsen-P (9–41 mg/kg) did not have clear relationship with mean livestock density (0.4–16.0 LSU/ha) in the 167 counties. There was also no clear relationship between livestock density and TP and Pox contents at farm level. However, livestock farms with cropland had higher TP and Pox contents than crop farms without livestock. Most livestock farms applied excessive amounts of manure to on-farm cropland and exported manure to crop farms within a distance of 5 km. Manure application on crop farms depended on crop types; 21 % of cereal fields, 31 % of cotton fields, 58 % of the orchards fields, and 65 % of the vegetable fields received manure regularly. The TP content of the subsoil was as high as or higher than the TP content of the topsoil in 21 % of the fields from livestock farms and 41 % of the fields from crop farms, which suggests P leaching. Our results indicate that livestock manures are not well utilized. There is a need for manure application limits, especially on livestock farms, and incentives for improving manure distribution and utilization.

The Mediterranean mountainous landscapes have undergone large-scale exploitation for millennia. In the Central Pyrenees, land abandonment has occurred since the 1950s, leading to a process of woody encroachment. The main objective of this paper is to shed light on the effects of different land use and land covers (LULCs) on soil organic carbon (SOC) and nitrogen (N) stocks, and on the composition of soil organic matter (SOM) after land abandonment in the Central Pyrenees. Five LULCs (8 specific sites) were selected through detailed land use change mapping. Soil and litter samples (n = 160) were collected and analyzed, including Tetramethylammonium hydroxide pyrolysis–gas chromatography. Organic carbon (Corg)/N ratios, Carbon Preference Index and Average Chain Length indices were calculated based on the distribution of fatty acids in order to determine the molecular composition and degradation of SOM. The results showed: (i) an increase in the dominance index and forest cover, at the expense of shrublands and agricultural fields, and a decrease in Shannon’s Diversity and Evenness indexes; (ii) LULC and depth had significant effects on SOC and N contents and stocks; (iii) SOC and N contents and stocks were higher in the meadows and young forests; (iv) significant differences were observed between meadows and young forests and the first stages of land abandonment considering the soil profile; (v) total decomposition of lignins and an omnipresence of unsaturated and saturated straight-chain fatty acids; and (vi) Corg/N values indicate that the origin of SOM is microbial. This study confirms that SOC accumulation after abandonment is a slow process, and the first stages of the woody encroachment decrease SOC stocks. Woody encroachment should be managed with measures based on scientific knowledge, but also considering the historic adaptation of agro-pastoral activities to the environment to ensure the proper functioning of ecosystem services and promote SOC storage in Mediterranean mountain soils.

In Rwanda, mulch is applied in coffee fields to control soil erosion. The objective of this paper is to quantify the effects of different types of mulch on soil properties and soil erodibility in coffee farming systems in three different agro-ecological zones of the highlands of Rwanda. The treatments consisted of five mulching systems (T1: Cympobogon spp.; T2: Panicum spp.; T3: Cympobogon spp. and Panicum spp.; T4: Eucalyptus spp. and Cympobogon spp.; T5: mixed residues) and control (un-mulched coffee - T6). The mulching systems were selected in coffee plantations to which the same mulch material had been applied annually at an average rate of 15–21 t mulch ha− 1 for at least three consecutive years before we started field experiments in 2007. We tested the effects from 2007 to 2008 on two soil types. A factorial two-way ANOVA was used to assess the effects of the application of different mulch types on the soil organic carbon, bulk density, wet aggregate stability, and soil erodibility at each site. The application of mulch significantly reduced the bulk density and soil erodibility (P < 0.001) and significantly increased the soil organic carbon and wet aggregate stability (P < 0.001), mainly at Kibirizi and Karongi. In addition, the effects of the interactions between the type of mulch and type of soil were site specific (P < 0.001). Low bulk densities and soil erodibility as well as high soil organic carbon and wet aggregate stability values were observed mainly in response to the application of a mixture of mulches, particularly T4 and T5 at rates of above 17 t ha− 1. The maximum erodibility values coincided with the lowest values of soil organic carbon and wet aggregate stability and the highest bulk density. In addition, soil erodibility was also affected by soil texture; high sand and very fine sand fractions increased the vulnerability of soils to erosion. Mulching demonstrated positive effects on soil properties and soil erodibility, but the effects were site specific, depending on the agro-ecological conditions of the study sites and the types of mulch used.

This paper presents the result of palynological research of peat relicts, found in the Westerkoggepolder (North-Holland, The Netherlands). In general, such relicts of peat in the actual landscape point to an extensive peat cover in the past that disappeared due to land reclamation and agricultural management. Improvement of the drainage in historical time resulted in shrinkage and bio-oxidation of peat. This caused a land surface lowering of at least 3 m and a transformation of Histosols in original peat deposits into eluvial clay covers with Mollic Gleysols. Similar processes occur in other regions in the world were people settled in areas with histosols and reclaimed land for food production. The last relicts of the former peat cover are valuable parts of the national soil archives and deserve the status of geoheritage.

This paper discusses the suitability of hand-held XRF analysis to extract palaeo-geochemical information from lacquer-peel soil sections that have been taken to document pedological information at geological and archaeological sites. This not only allows the study of sections from archaeological and geological sites that have since disappeared, but can also answer new archaeological questions on the nature of activities undertaken at such sites. Seven lacquer-peels, from different time-periods and different geogenetic backdrops, have been studied with hand-held XRF (Niton XL3t, GOLDD detector). Five of these lacquer-peels were studied to assess possible interference from mounting materials (glues, textiles and framing boards) used. Four of these lacquer-peels were studied for their palaeo-geochemical information. These lacquer-peels were taken from prehistoric agricultural plots and settlement sites, ranging in age from the Neolithic to the Iron Age. Values for Si, K, Al, Fe, Ti, Sr, Zr and Rb reflect lithogenetic and pedological processes. The contents of S, Ca and P were used as a proxy for anthropogenic influence. The lacquer-peels provided consistent and reliable geochemical readings with the hand-held XRF. Observed correspondence between pedological predictions, archaeological hypotheses and the measured results testifies to the suitability of hand-held XRF for palaeo-geochemical characterization. Interference from the primarily organic fixing- and mounting-agents used was absent. Consequently, hand-held XRF analysis allows extraction of palaeo-geochemical information from lacquer-peel soil sections, which opens-up a new potential data-set for reconstructing past pollution and to geochemically re-assess geological and archaeological sites from existent lacquer peels — adding a geochemical dimension to lacquer-peels of pedological, archaeological and geological sites.

Water erosion creates negative impacts on agricultural production, infrastructure, and water quality across the world. Regional-scale water erosion assessment is important, but limited by data availability and quality. Satellite remote sensing can contribute through providing spatial data to such assessments. During the past 30 years many studies have been published that did this to a greater or lesser extent. The objective of this paper is to review methodologies applied for water erosion assessment using satellite remote sensing. First, studies on erosion detection are treated. This comprises the detection of erosion features and eroded areas, as well as the assessment of off-site impacts such as sediment deposition and water quality of inland lakes. Second, the assessment of erosion controlling factors is evaluated. Four types of factors are discussed: topography, soil properties, vegetation cover, and management practices. Then, erosion mapping techniques are described that integrate products derived from satellite remote sensing with additional data sources. These techniques include erosion models and qualitative methods. Finally, validation methods used to assess the accuracy of maps produced with satellite data are discussed. It is concluded that a general lack of validation data is a main concern. Validation is of utmost importance to achieve regional operational monitoring systems, and close collaboration between the remote sensing community and field-based erosion scientists is therefore required.

There is increased awareness of the environmental impacts of soil carbon (C) and nitrogen (N) losses through wind erosion, especially in areas heavily affected by dust storm erosion. This paper reviews the recent literature concerning dust storm-related soil erosion and its impact on soil C and N losses in northern China. The purpose of our study is to provide an overview of the area of erosion-affected soils and to estimate the magnitude of soil C and N losses from farmland affected by dust storm erosion. According to the second national soil erosion remote-sensing survey in 2000, the area affected by wind erosion was 1.91 million km 2 , accounting for 20% of the total land area in China. This area is expanding quickly as the incidence of heavy dust storms has greatly increased over the last five decades, mainly as a result of the intensification of soil cultivation. The economic and ecological damage caused by wind erosion is considerable. Heavily affected areas show a loss of nutrients and organic carbon in soils and the heavily degraded soils are much less productive. Compared with the non-degraded soil, the C and N contents in degraded soils have declined by 66% and 73%, respectively. The estimated annual losses per cm toplayer of soil C and N by dust storm erosion in northern China range from 53 to 1044 kg ha − 1 and 5 to 90 kg ha − 1 , respectively. Field studies suggest that soil losses by wind erosion can be reduced by up to 79% when farmers shift from conventional soil tillage methods to no-till. Thus shifting to no-till or reduced tillage systems is an effective practice for protecting soil and soil nutrients. Our study indicates that soil conservation measures along with improved soil fertility management measures should be promoted in dry-land farming areas of northern China. As erosion is a major mechanism of nutrient withdrawal in these areas, we plead for the development of accurate methods for its assessment and for the incorporation of erosion, as a nutrient output term, in nutrient budget studies.

Land degradation is a crucial issue in mountainous areas and is manifested in a variety of processes. For its assessment, application of existing models is not straightforward. In addition, data availability might be a problem. In this paper, a procedure for land degradation assessment is described, which follows a four-step approach: (1) detection, inventory and mapping of land degradation features, (2) assessing the magnitude of soil loss, (3) study of causal factors, and (4) hazard assessment by applying decision trees. This approach is applied to a case study in the Middle Mountain region of Nepal. The study shows that individual mass movement features such as debris slides and slumps can be easily mapped by photo interpretation techniques. Application of soil loss estimation models helps get insight on the magnitude of soil losses. In the study area, soil losses are higher in rainfed crops on sloping terraces (highest soil loss is 32 tons/ha/year) and minimal under dense forest and in irrigated rice fields (less than 1 ton/ha/year). However, there is high frequency of slope failures in the form of slumps in the rice fields. Debris slides are more common on south-facing slopes under rainfed agriculture or in degraded forest. Field evidences and analysis of causal factors for land degradation helps in building decision trees, the use of which for modelling land degradation has the advantage that attributes can be ranked and tested according to their importance. In addition, decision trees are simple to construct, easy to implement and very flexible in adaptations.

Over the past years the Caesium-137 (137Cs) technique has been successfully applied in numerous environments all over the world. This technique is using the worldwide distribution of the anthropogenic 137Cs radionuclide and its redistribution associated with soil particles as an effective estimation of net soil-loss rates. In contrast to numerous studies on deep, often cultivated, clay soils with gentle to intermediate slopes, typical Mediterranean shallow stony soils on steep slopes have received less attention. In this paper, the landscape evolution over the past 37 years has been evaluated using the 137Cs technique for two lithological different areas under contrasting land use in the Álora case study area (Málaga, Spain). In soils on gneiss and serpentinite bedrock several transects have been selected on steep slopes up to 35° with mean soil depths from 37 cm for gneiss to 24 cm for serpentinite. Estimating net soil redistribution rates from radionuclide distributions depends on the calculation of the local area reference inventory and the used calibration technique. Several methods have been tested and final results were found to differ considerably. After careful parameter selection, the resulting net soil redistribution estimates for the different transects have been compared with simulations of a simple landscape evolution model, resulting in different possible scenarios of erosional response. Total net soil-loss for the study area range from 2.3±0.25 to 69.1±7.8 t ha−1 year−1 for serpentinite and gneiss slopes, respectively. Differences in total slope sediment budgets as well as differences along the transects reveal influences of landscape representation and land use. In this case the impact of soil translocation by tillage and resulting erosion rates are far more important than possible parent material induced differences. However, comparing the two sampled areas not only net rates but spatial patterns as well reveal important differences in distribution over the landscape of net erosion and net sedimentation zones., This research is supported by the Laboratory of Soil Science and Geology under the project “Multi-scale Landscape Process Modelling” at Wageningen University. The second author acknowledges the financial support through a post-doctoral fellowship of the Fundación Alfonso Martín Escudero (Madrid, Spain).

Due to its modest data demands and transparent model structure, the Universal Soil Loss Equation (USLE) remains the most popular tool for water erosion hazard assessment. However, the model has several shortcomings, two of which are likely to have prominent implications for the model results. First, the mathematical form of the USLE, the multiplication of six factors, easily leads to large errors whenever one of the input data is misspecified. Second, the USLE has a modest correlation between observed soil losses and model calculations, even with the same data that was used for its calibration. This raises questions about its mathematical model structure and the robustness of the assumed parameter values that are implicitly assigned to the model. This paper, therefore, analyzes if the USLE could benefit from mathematical model transformations that, on one hand, mitigate the impact of incorrect input factors and, on the other hand, result in a better fit between model results and observed soil losses. For the analysis, we revisit the original data set and consider the USLE factors as variables rather than their common interpretation as parameters. We first use both nonparametric and parametric techniques to test the robustness of the implicit parameter assignments in the USLE equation. Next, we postulate alternative mathematical forms and use parametric test statistics to evaluate parameter significance and model fit. A tenfold cross-validation of the model with the best fit tests the sensitivity of the parameters for inclusion or exclusion of the data. The results show that the USLE model is not very robust, however, only slight model improvements are obtained by drastic modifications of its functional form, thereby sacrificing the simple model structure that was intended by its designers. © 2002 Elsevier Science B.V. All rights reserved.

One of the tasks of the International Geosphere–Biosphere Programme–Global Change and Terrestrial Ecosystems (IGBP–GCTE) Soil Erosion Network is to determine the suitability of modelling approaches for the estimation of soil erosion under global change. To achieve this, current erosion models are being evaluated in a series of GCTE meetings. This paper presents a synthesis of results from the first two meetings, which focused upon models for soil erosion by water at field and catchment scales, respectively. Apart from this comparison, discussions were held on model use and quality. The main conclusions from these discussions are included here as well. For both sets of evaluations, common datasets which had been split into a `training set' and a `testing set' were prepared and distributed to the participating modellers. For the `testing set' data, measured values for runoff and sediment yield (field-scale models) or for erosion only (catchment-scale models) were withheld from the modellers. The data used for the field-scale evaluation represented 73 site-years from seven sites in three countries: six field-scale erosion models took part in the evaluation. For the catchment-scale evaluation, data for 10 events on a 40 ha catchment in the Netherlands was used to evaluate seven catchment models. Conclusions from both field-scale and catchment-scale exercises include the following: • calibration is desirable for many models, and necessary for some. Calibration is most effective if the event(s) to be estimated lie inside the range of calibration events; • total discharge is generally better predicted than peak discharge and both are better predicted than sediment discharge; • for continuous-simulation models, long-term average results are better simulated than results for individual time periods. In general, results are less good for shorter time periods, although there are exceptions; • while for certain events models may not perform well (absolute results), correlation coefficients between observed and predicted values are acceptable (relative results); • at a catchment scale, the predicted spatial runoff pattern is as important as a correct prediction of the net output; • from the discussions it was clear that additional `soft' information, in particular regarding the change in soil structure as a result of agricultural activities and/or climate, greatly improves the quality of input data and model results.

Knowledge of groundwater flow, and accordingly, groundwater residence time is immensely important for the sustainable management of groundwater resources. This requires a good conceptual model of the aquifer system. In this paper, a conceptual model based on the interpretations of hydrogeological and hydrochemical data, as well as measurements of environmental tracers ( 18 O, 2 H, 3 H) was formulated for a semiconfined aquifer system in Eastern Slavonia in Croatia. The aquifer system is composed of Quaternary gravel and sand and silty–clayey interlayers and is covered with low permeability deposits. Measurements of water levels and environmental tracers in the study area clarified the groundwater flow evolution from the recharge area to the discharge area. The content of stable isotopes confirmed that the groundwater originates from precipitation. The tritium content and geochemical processes (such as cation exchange, silicate weathering) suggested a relatively long residence time of groundwater in the part of the aquifer system that is further from the Sava River. The same is confirmed by the results of calculated particle tracking pathlines.

Tree growth and inclination on sloping land is affected by mass movement. Suitable analysis of tree growth and tree form can therefore provide considerable information on mass movement activity. This paper reports a new, automated method for studying the temporal and spatial aspects of mass movement activity. Ringwidth data from only a few cores per tree are required. The method uses filtering techniques and statistical time series analysis. Preliminary results for two landslides in the Barcelonnette area of the French Alps show a relative stability of movement activity over the last hundred years (no trend) and short periodicity (six to seven year periods) of mass movement activity. The advantages of the method (over other, mostly visual, methods) are its clearness, flexibility, repeatability and rapidity. However, further testing is needed to examine its reliability.

Rotational landslides (slumps) varying in size can develop at different slope angles in the same type of cohesive regolith material. Therefore it is possible to set up independent equilibrium equations for these rotational slides of different size. In this way, a good estimate of the mean strength parameters of a certain type of material can be obtained on the basis of a number of these independent equilibrium equations. This can be done by means of regression analyses and the correlation coefficients and variances give a good indication of the reliability of the estimate of the strength parameters. In this paper the strength parameters of two regolith materials on schist and claystone are determined in this way and compared with the strength parameters measured in the laboratory.

Mediterranean environments are especially susceptible to soil erosion and to inappropriate soil management, leading to accelerated soil loss. Sustainable Land Management (SLM) practices (such as reduced tillage, no-tillage, cover crops, etc.,) have the potential to reduce soil, organic carbon (OC), and nutrient losses by erosion. However, the effectivity of these practices is site-dependent and varies under different rainfall conditions. The objective of this paper was to evaluate the effects of SLM practices in two rainfed systems (a wheat field and an almond orchard) representative of a large area of the driest Mediterranean regions - on runoff, soil erosion, particle size distribution, and OC and nutrient (N and P) contents in sediments. The influence of the rainfall characteristics on the effectiveness of the SLM practices was also evaluated. The SLM implemented were: reduced tillage (RT) in the wheat field and almond orchard and reduced tillage combined with green manure (RTG) in the almond orchard; these were compared to conventional tillage, the usual practice in the area. Open erosion plots were set up to monitor the effects of SLM on soil carbon and nutrients and on soil erosion after each rainfall event over six years (2010 2016). The results show that the SLM practices evaluated resulted in increased organic carbon (OC) and nutrients (N and P) contents in the soil, and reduced runoff, erosion, and mobilization of organic carbon and nutrients in sediments. Reductions in runoff of 30% and 65% and decreases in erosion of 65 and 85% were found in the wheat field and almond orchards, respectively. In addition, the total OC, N, and P losses in the wheat field were reduced by 56%, 45%, and 64%, respectively, while in the almond field the OC, N, and P losses were reduced by 90% under RT and by 85% under RTG. The beneficial effect of the SLM practices on soil erosion was observed within 18 months of their implementation and continued throughout the six years of the study. Furthermore, the effectiveness of tillage reduction with respect to erosion control and carbon and nutrients mobilization was highest during the most intense rainfall events, which are responsible for the highest erosion rates in Mediterranean areas. Our results support the key role of SLM practices under semiarid conditions as useful tools for climate change mitigation and adaptation, given the expected increase in high-intensity rainfall events in semiarid areas. © 2019 The Authors This study site has been funded by several national (CYCIT AGL201125069//CICYT AGL2010-20941//CGL2013-42009-R//CGL2014-55-405-R), Regional (Séneca Foundation: 08757/PI/08//19350/PI/14), and European Commission H2020 (F6 DG RTD 037046 and Grant 728003, DIVERFARMING projects). Joris de Vente acknowledges support from a Ramón y Cajal research grant (RYC-2012-10375) and María Almagro was supported by the Juan de la Cierva Program (IJCI-2015-23500).