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This experiment tested whether it was possible to incorporate broiler litter (BL) or cattle farmyard manure (FYM) into a 7-yr arable rotation on a sandy soil without causing an increase in nitratenitrogen (NO 3 -N) leaching. Four manure treatments (with adjusted fertilizer inputs), varying in frequency and timing of application, were imposed on the rotation and compared with a control that received inorganic fertilizer according to recommended rates. Over seven winters, the annual average NO 3 -N leached from the inorganic fertilizer treatment (control) was 39 kg/ha in 183 mm drainage. Total manure N loadings over the period of the experiment ranged between 557 and 1719 kg/ha (80-246 kg/ha/yr) for the four treatments. Three of the four manure treatments significantly increased NO 3 -N leaching over the rotation (P < 0.001). Annual applications of FYM (1719 kg/ha manure N or 246 kg/ha/yr) increased NO 3 -N leaching by 39%. We hypothesize that this was due to increased mineralization of the organic N accumulating from repeated FYM applications. BL applied each year (1526 kg/ha manure N or 218 kg N/ha/yr) increased NO 3 -N leaching by 52% above the control; BL applied 5 of 7 yr (972 kg/ha manure N or 139 kg N/ha/yr on average) and including inadvisable autumn applications increased leaching by 50%. BL applied in late winter or early spring every 2-3 yr (557 kg/ha manure N or 80 kg N/ha/yr on average) resulted in NO 3 -N leaching similar to the control. This suggests that to avoid additional NO 3 -N leaching from manure use in an arable rotation, manure should not be applied every year and autumn applications should be avoided; there are real challenges where manure is used on an annual basis.

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Abstract. Soil condition or quality determines its ability to deliver a range of functions that support ecosystem services, human health and wellbeing. The increasing policy imperative to implement successful soil monitoring programmes has resulted in the demand for reliable soil quality indicators (SQIs) for physical, biological and chemical soil properties. The selection of these indicators needs to ensure that they are sensitive and responsive to pressure and change, e.g. they change across space and time in relation to natural perturbations and land management practices. Using a logical sieve approach based on key policy-related soil functions, this research assessed whether physical soil properties can be used to indicate the quality of British soils in terms of their capacity to deliver ecosystem goods and services. The resultant prioritised list of physical SQIs was tested for robustness, spatial and temporal variability, and expected rate of change using statistical analysis and modelling. Seven SQIs were prioritised: soil packing density, soil water retention characteristics, aggregate stability, rate of soil erosion, depth of soil, soil structure (assessed by visual soil evaluation) and soil sealing. These all have direct relevance to current and likely future soil and environmental policy and are appropriate for implementation in soil monitoring programmes.

Grasslands are at risk of degradation due to unsustainable management practices and climate change. Here, we review the principal soil quality indicators (SQIs) to evaluate the sustainability of different grassland management practices globally. We discuss the importance of SQI assessment and the Soil Quality Minimum Dataset (MDS) specifically in the context of grasslands. We then review two potential solutions, the first of which is adopting grazing management, whereby sustainable grazing management plans (GMPs) offer great potential. The other solution is the development and adoption of novel grassland species, which may improve either drought resistance or infiltration rates, erosion and flooding. Sustainable grassland soil management can promote ecosystem service delivery and improve the resilience of the entire grassland ecosystem to anthropogenic change.