Dutch soil management and soil fertility

The organic sector depends heavily on its soils. In the Netherlands, relatively little acreage is available per farm compared to other countries. This means that the soil has to be kept in optimal shape for production, be it vegetables, cereals, potatoes or animal feed and grassland. To facilitate organic farmers, Wageningen UR and Louis Bolk Institute carry out a variety of research aimed specifically at soil management and soil fertility. The report contains sector facts, sector aspirations, current affairs and research projects

Soil, Water, and Nutrient Management Research: A New Agenda

IBSRAM position paper prepared by a panel of five experts, headed by Dennis Greenland. The report assesses the state of current international soil, water, and nutrient management (SWNM) research and outlines new strategies and organizing principles for its integration and improvement. There is a preface by Nyle Brady.Distributed for those attending the, CGIAR Mid Term Meeting, May 1994, for consideration in connection with the report of the Agenda 21 task force

Detailed soil survey of eight watercourse command areas in Chishtian and Hasalpur tehsils

Irrigation management / Hydraulics / Channel improvement / Watercourses / Soil surveys / Hydrology / Climate / Mapping / Hydraulics / Infiltration / Pakistan / Fordwah / Azim

Changes to soil quality indicators following conversion to organic vegetable production (OF0401)

This is the final report of Defra project OF0401. The attached report document starts with an Executive Summary, from which this text is extracted. The aim of this 1 year study was to examine how key functional indicators of soil quality are affected by contrasting organic and conventional management regimes. In particular, the project investigated the impact of contrasting fertility building regimes on soil quality, focussing on the initial 5-year period following conversion from conventional to organic production. Five 0.8 ha areas at HRI-Wellesbourne were selected for study. These were: two organic vegetable rotations supporting contrasting fertility building regimes, an organic arable rotation, a grass-clover ley, and a conventionally managed cereal rotation. The organic areas had been converted from conventional cereal production 5 years prior to the start of the study. The conventional area was adjacent. A range of chemical, biological and physical attributes were determined. There were differences between the organic and conventional management regimes in most chemical, biological and physical soil quality parameters. Contrasting organic management regimes had different effects on soil quality. Relative to organic vegetable and conventional arable management, the organic arable management rotation enhanced amounts of light fraction organic matter and labile N, with beneficial implications for long term nutrient retention and soil organic matter development. There was little difference in chemical quality between the organic vegetable and the conventional arable areas. There was evidence that organic management promoted a microbial community that was distinct in composition and functional attributes to that in conventional soil. Relative to conventional management, areas under organic management had greatly increased inoculum of arbuscular mycorrhizal fungi, a larger proportion of 'active' relative to 'resting' biomass within the microbiota, increased metabolic diversity and a distinct microbial community metabolism. However, there was evidence that the productivity of newly converted organic systems could be limited by low inoculum and diversity of arbuscular mycorrhizal fungi inherited following conventional management. The clearest effect on soil structure was with regard to the detrimental effects of vegetable production rather than to any benefit associated with organic management. Wheeling lines caused compaction that resulted in poor growth of subsequent cereal crops. However, it is likely that increased levels of organic matter may result in a soil better able to cope with damaging operations. There were differences in the susceptibility of the chemical and biological quality parameters to change. These differences provide possibilities to use selected parameters as early indicators of the effects of management on soil quality. Furthermore, the results highlight the need, when investigating soil quality, to consider a wide variety of 'quality' analyses. Limited data sets, focussing on traditional measures of soil quality (e.g. total SOM and biomass-N), could lead to unsound conclusions regarding the effects of management on other functional aspects of soil quality. There are opportunities to conduct further statistical analysis of our comprehensive data set in order to develop an index suitable for quantifying soil quality in organic systems. Such an index would be of generic value to rate soil quality in diverse agricultural systems. Further work is needed to determine the applicability and conclusions of our study to other soil types and organic management regimes. The work has highlighted fundamental shifts in microbial community structure and functioning following conversion from conventional to organic management. There is a need to characterise and quantify these changes. This will provide new groups of 'indicator' organisms which could be suitable for assessing changes to soil quality, and could also provide opportunities to manage soil microbial communities to improve the sustainability of organic and conventional farming

Impact of soil management practices on soil fertility and disease suppressiveness

Soil management practices are targeted to provide adequate crop nutrition and to ensure durable soil fertility and to avoid negative environmental impacts. Soil management also aims to reduce pest and disease pressure on crops. Organic farming is believed to increase soil suppressiveness towards soil-borne diseases as well aerial diseases. In this paper we will discuss the potential of soil manage-ment as a tool to improve disease suppressiveness in practice

Land use decision modeling with dynamically updated soil carbon emission rates

Soil carbon can be sequestered through different land management options depending on the soil carbon status at the beginning of a management period. This initial status results from a given soil management history in a given soil climate regime. Similarly, the prediction of future carbon storage depends on the time sequence of future soil management. Unfortunately, the number of possible management trajectories reaches non-computable levels so fast that explicit representations of management trajectories are impractical for most existing land use decision models. Consequently, the impact of different management trajectories has been ignored. This article proposes a computationally feasible mathematical programming method for integration of soil status dependent sequestration rates in land use decision optimization models. The soil status is represented by an array of adjacent status classes. For each combination of soil management and initial soil status class, transition probabilities of moving into a new or staying in the same status class are computed. Subsequently, these probabilities are used in dynamic equations to update the soil status level before and after each new soil management period. To illustrate the impacts of the proposed method, a simple hypothetical land use decision model is solved for alternative specifications.Soil carbon sequestration, Sink dynamics, Mathematical programming, Land use, Optimization, Agriculture, Forestry, Greenhouse gas mitigation

The effects of organic farming on the soil physical environment

The aim of this research was to investigate the effects of organic farming practices on the development of soil physical properties, and in particular, soil structure in comparison with conventional agricultural management. The soil structure of organically and conventionally managed soils at one site was compared in a quantitative manner at different scales of observations using image analysis. Key soil physical and chemical properties were measured as well as the pore fractal geometry to characterise pore roughness. Organically managed soils had higher organic matter content and provided a more stable soil structure than conventionally managed soils. The higher porosity (%) at the macroscale in soil under conventional management was due to fewer larger pores while mesoand microscale porosity was found to be greater under organic management. Organically managed soils typically provided spatially well distributed pores of all sizes and of greater roughness compared to those under conventional management. These variations in the soil physical environment are likely to impact significantly on the performance of these soils for a number of key processes such as crop establishment and water availabilit

Soil health and ecosystem services: Lessons from sub-Sahara Africa (SSA)

Management practices to improve soil health influence several ecosystem services including regulation of water flows, changes in soil biodiversity and greenhouse gases that are important at local, regional and global levels. Unfortunately, the primary focus in soil health management over the years has been increasing crop productivity and to some extent the associated economics and use efficiencies of inputs. There are now efforts to study the inter-relationship of associated ecosystem effects of soil health management considering that sustainable intensification cannot occur without conscious recognition of these associated non-provisioning ecosystem services. This review documents the current knowledge of ecosystem services for key management practices based on experiences from agricultural lands in sub-Sahara Africa (SSA). Here, practicing conservation agriculture (CA) and Integrated Soil fertility management (ISFM) have overall positive benefits on increasing infiltration (> 44), reducing runoff (> 30%) and soil erosion (> 33%) and increases soil biodiversity. While ISFM and Agroforestry increase provisioning of fuelwood, fodder and food, the effect of CA on the provisioning of food is unclear. Also, considering long-term perspectives, none of the studied soil health promoting practices are increasing soil organic carbon (SOC). Annual contributions to greenhouse gases are generally low (< 3 kg N2O ha−1) with few exceptions. Nitrogen leaching vary widely, from 0.2 to over 200 kg N ha−1 and are sometimes inconsistent with N inputs. This summary of key considerations for evaluating practices from multiple perspectives including provisioning, regulating, supporting and cultural ecosystem services is important to inform future soil health policy and research initiatives in SSA

The soil quality concept as a tool for exposing values in science and promoting sustainability considerations

The term soil quality has mainly been used as a technical concept for grading soils. It is important that the values and goals in soil use planning and soil management are explicitly stated and related to the soil quality indicators. Such a cognitive soil quality concept may facilitate the urgent need of soil scientists to interact with stakeholders in the society. Useful approaches for such exercises have been proposed in the literature. A shift in research paradigm away from the classical, positivistic, ‘value-neutral’ approach is, however, a prerequisite for a fruitful outcome of this endeavour. The reflexive objectivity is a valuable tool in differentiating the basic scientific observations from societal priorities and personal values of the scientist. Other suggestions of associating ‘post-positivistic-science’ societal priorities to observations and experiments (e.g., ‘precautionary’ science) are strongly dissuaded. The suggested increase in focus on sustainability-based decisions on soil management induces a recommended search for ‘management thresholds’ rather than the more descriptive ‘soil quality indicator benchmarks/thresholds’. I strongly recommend the ESSC to increase its activities on prescriptive and management-oriented research and in this endeavour make use of the proposals given above