Anita Shepherd

The North Wyke Farm Platform: effect of temperate grassland farming systems on soil moisture contents, runoff and associated water quality dynamics

Summary The North Wyke Farm Platform was established as a United Kingdom national capability for collaborative research, training and knowledge exchange in agro‐environmental sciences. Its remit is to research agricultural productivity and ecosystem responses to different management practices for beef and sheep production in lowland grasslands. A system based on permanent pasture was implemented on three 21‐ha farmlets to obtain baseline data on hydrology, nutrient cycling and productivity for 2 years. Since then two farmlets have been modified by either (i) planned reseeding with grasses that have been bred for enhanced sugar content or deep‐rooting traits or (ii) sowing grass and legume mixtures to reduce nitrogen fertilizer inputs. The quantities of nutrients that enter, cycle within and leave the farmlets were evaluated with data recorded from sensor technologies coupled with more traditional field study methods. We demonstrate the potential of the farm platform approach with a case study in which we investigate the effects of the weather, field topography and farm management activity on surface runoff and associated pollutant or nutrient loss from soil. We have the opportunity to do a full nutrient cycling analysis, taking account of nutrient transformations in soil, and flows to water and losses to air. The NWFP monitoring system is unique in both scale and scope for a managed land‐based capability that brings together several technologies that allow the effect of temperate grassland farming systems on soil moisture levels, runoff and associated water quality dynamics to be studied in detail. Highlights Can meat production systems be developed that are productive yet minimize losses to the environment? The data are from an intensively instrumented capability, which is globally unique and topical. We use sensing technologies and surveys to show the effect of pasture renewal on nutrient losses. Platforms provide evidence of the effect of meteorology, topography and farm activity on nutrient loss.

Cost effectiveness of nitrate leaching mitigation measures for grassland livestock systems at locations in England and Wales

As much as 60% of the nitrate in water in England is thought to derive from agriculture. Legislation aims to improve water quality by limiting nitrate concentration in surface and groundwaters to 50 mg l(-1). The UK Government responded to the requirements of the EC Nitrate Directive by delineating Nitrate Vulnerable Zones (NVZs) to cover 55% of England in 2002 and increased it to 70% in 2009. In this study we assessed the cost-effectiveness of measures for implementation in livestock systems to mitigate nitrate leaching in the UK. These estimates were prepared for a range of hypothetical farms representative of typical dairy, beef and sheep farms at different locations in England and Wales and for a list of mitigation measures identified to reduce leaching. The NGAUGE and NFixCycle models were used to estimate leaching from these systems. The costs of implementation of the mitigation measures were also assessed in order to evaluate the cost-effectiveness of these measures. In general, the most effective measures to reduce leaching for all systems were the ones that involved a reduction in stocking rates and grazing time, followed by those involving improvements in fertiliser and crop management. Only in the case of the dairy system was effectiveness affected by location of the farm. The costs for implementation in the sheep system were relatively low compared with beef and dairy systems. Implementation of some of the measures with high cost-effectiveness would need to be incentivised financially or with legislation due to the high costs involved.

A Review of Quantitative Tools for Assessing the Diffuse Pollution Response to Farmer Adaptations and Mitigation Methods Under Climate Change

In an era of global climate change, the agricultural sector faces the challenge of increasing the production of safe and nutritious food supplies to meet a growing world population while safeguarding the environment. Farmers will adapt their agricultural practices to a changing climate to safeguard against loss of production and to take advantage of any positive climatic conditions. Certain management practices have been found to reduce the effects of agricultural practices on the environment and a key question is how efficient these are under the current climate, and will these management practices still be relevant under a changing climate? Mathematical modeling is the only tool available to assess the potential efficacy of proposed agricultural management practices to help evaluate their impacts on the environment in a future climate. This chapter attempts to evaluate a range of published models for their capability to simulate agricultural production systems and associated environmental system losses under a changing climate, and their ability to introduce farmer adaptation and mitigation methods. The chapter focuses on the applicability of the models given a set of essential criteria related to scale, biophysical processes, and land management. Thirty models are initially examined, based on details found in published papers, against specific criteria, viz: (1) spatial scale and temporal scale, ease of use, and ability to consider a change in climate; (2) ability to simulate nutrient cycling processes, specifically carbon and nitrogen dynamics with microbial turnover, mineralization–immobilization, nitrification and denitrification, plant nutrient uptake, and phosphorus cycling; (3) ability to consider a water balance and water movement through soil; and (4) ability to introduce and modify agricultural practices relating to crop and livestock management. The chapter does not compare any actual model simulations. It was concluded that albeit no single model incorporates all above stated requirements, there were three models, DAYCENT, PASIM, and SPACSYS which will accommodate most features. These models may therefore be considered in the context of this chapter to be the most suitable for a general assessment of the effects of farm mitigation and adaptation on environmental losses under a changing climate.

Spatially detailed retrievals of spring phenology from single-season high-resolution image time series

Vegetation indices derived from satellite image time series have been extensively used to estimate the timing of phenological events like season onset. Medium spatial resolution (≥250 m) satellite sensors with daily revisit capability are typically employed for this purpose. In recent years, phenology is being retrieved at higher resolution (≤30 m) in response to increasing availability of high-resolution satellite data. To overcome the reduced acquisition frequency of such data, previous attempts involved fusion between high- and medium-resolution data, or combinations of multi-year acquisitions in a single phenological reconstruction. The objectives of this study are to demonstrate that phenological parameters can now be retrieved from single-season high-resolution time series, and to compare these retrievals against those derived from multi-year high-resolution and single-season medium-resolution satellite data. The study focuses on the island of Schiermonnikoog, the Netherlands, which comprises a highly-dynamic saltmarsh, dune vegetation, and agricultural land. Combining NDVI series derived from atmospherically-corrected images from RapidEye (5 m-resolution) and the SPOT5 Take5 experiment (10m-resolution) acquired between March and August 2015, phenological parameters were estimated using a function fitting approach. We then compared results with phenology retrieved from four years of 30 m Landsat 8 OLI data, and single-year 100 m Proba-V and 250 m MODIS temporal composites of the same period. Retrieved phenological parameters from combined RapidEye/SPOT5 displayed spatially consistent results and a large spatial variability, providing complementary information to existing vegetation community maps. Retrievals that combined four years of Landsat observations into a single synthetic year were affected by the inclusion of years with warmer spring temperatures, whereas adjustment of the average phenology to 2015 observations was only feasible for a few pixels due to cloud cover around phenological transition dates. The Proba-V and MODIS phenology retrievals scaled poorly relative to their high-resolution equivalents, indicating that medium-resolution phenology retrievals need to be interpreted with care, particularly in landscapes with fine-scale land cover variability.

Contextualized Geographically Weighted Principal Components Analysis for Investigating Baseline Soils Data on the North Wyke Farm Platform

The UK’s North Wyke Farm Platform (NWFP) for sustainable grassland farming is set up as a large agriculture modelling system of 15 hydrologically-isolated catchments, where in each catchment, water chemistry, precipitation and soil moisture data are continuously monitored. This spatio-temporal data are then interrogated with respect to climatic timings and changes in crop, livestock and farm management, across the NWFP. Complementary data sets are also found via spatial field surveys, remote sensing and greenhouse gas studies. This study focuses on one such field survey, consisting of soils data at 495 sites. We spatially explore this data using a geographically weighted principal components analysis, where we provide a novel adaptation of the technique to deal with the distinctly partitioned nature of the data, which is collected across 20 fields, spread over the 15 catchments.

The North Wyke Farm Platform: effect of temperate grassland farming systems on soil moisture contents, runoff and associated water quality dynamics: North Wyke Farm Platform

Summary The North Wyke Farm Platform was established as a United Kingdom national capability for collaborative research, training and knowledge exchange in agro‐environmental sciences. Its remit is to research agricultural productivity and ecosystem responses to different management practices for beef and sheep production in lowland grasslands. A system based on permanent pasture was implemented on three 21‐ha farmlets to obtain baseline data on hydrology, nutrient cycling and productivity for 2 years. Since then two farmlets have been modified by either (i) planned reseeding with grasses that have been bred for enhanced sugar content or deep‐rooting traits or (ii) sowing grass and legume mixtures to reduce nitrogen fertilizer inputs. The quantities of nutrients that enter, cycle within and leave the farmlets were evaluated with data recorded from sensor technologies coupled with more traditional field study methods. We demonstrate the potential of the farm platform approach with a case study in which we investigate the effects of the weather, field topography and farm management activity on surface runoff and associated pollutant or nutrient loss from soil. We have the opportunity to do a full nutrient cycling analysis, taking account of nutrient transformations in soil, and flows to water and losses to air. The NWFP monitoring system is unique in both scale and scope for a managed land‐based capability that brings together several technologies that allow the effect of temperate grassland farming systems on soil moisture levels, runoff and associated water quality dynamics to be studied in detail. Highlights Can meat production systems be developed that are productive yet minimize losses to the environment? The data are from an intensively instrumented capability, which is globally unique and topical. We use sensing technologies and surveys to show the effect of pasture renewal on nutrient losses. Platforms provide evidence of the effect of meteorology, topography and farm activity on nutrient loss.

The North Wyke Farm Platform

Summary The North Wyke Farm Platform was established as a United Kingdom national capability for collaborative research, training and knowledge exchange in agro‐environmental sciences. Its remit is to research agricultural productivity and ecosystem responses to different management practices for beef and sheep production in lowland grasslands. A system based on permanent pasture was implemented on three 21‐ha farmlets to obtain baseline data on hydrology, nutrient cycling and productivity for 2 years. Since then two farmlets have been modified by either (i) planned reseeding with grasses that have been bred for enhanced sugar content or deep‐rooting traits or (ii) sowing grass and legume mixtures to reduce nitrogen fertilizer inputs. The quantities of nutrients that enter, cycle within and leave the farmlets were evaluated with data recorded from sensor technologies coupled with more traditional field study methods. We demonstrate the potential of the farm platform approach with a case study in which we investigate the effects of the weather, field topography and farm management activity on surface runoff and associated pollutant or nutrient loss from soil. We have the opportunity to do a full nutrient cycling analysis, taking account of nutrient transformations in soil, and flows to water and losses to air. The NWFP monitoring system is unique in both scale and scope for a managed land‐based capability that brings together several technologies that allow the effect of temperate grassland farming systems on soil moisture levels, runoff and associated water quality dynamics to be studied in detail. Highlights Can meat production systems be developed that are productive yet minimize losses to the environment? The data are from an intensively instrumented capability, which is globally unique and topical. We use sensing technologies and surveys to show the effect of pasture renewal on nutrient losses. Platforms provide evidence of the effect of meteorology, topography and farm activity on nutrient loss.