A GIS-Based Approach to Site Vegetated Buffer Strips for Erosion Control
Within an Agricultural Catchment in Southern England
Abstract
Agricultural soil erosion is largely attributed to arable
extensification and increased mechanisation. Runoff from arable land and
intensively managed grassland transports sediment and contaminants
across the landscape and into watercourses, causing crop loss, land
degradation and water quality issues. One low-cost and low-maintenance
nature-based mitigation approach is the implementation of vegetated
buffer strips (VBS): grassland sited along field margins to trap
sediment and contaminants, reducing transportation and diffuse pollution
rates. GIS modelling using remotely sensed landscape indices and land
parcel data can provide an efficient means of identifying priority areas
for intervention at sub-catchment or farm system scales. We develop and
test a scalable runoff risk model in the lower Rother catchment, West
Sussex. The model uses the Normalised Difference Vegetation Index (NDVI)
applied to satellite images as an erodibility proxy and identifies
locations along pathways that are conceivably at greatest risk of
sediment accumulation and transfer, guided by field observations.
Current and historical field boundaries near high-risk locations are
evaluated for their potential capacity to reduce runoff using an
innovative ranking system. Recommendations are made for VBS
implementation and utility of historical field margin restoration is
discussed. Our method offers a rapid approach with minimal data
requirements to identify high-risk erosion locations and priority sites
for intervention. The tool has the potential to guide decision-makers
responsible for targeting and implementing soil erosion control measures
such as VBS, while also maximising agri-environmental and cultural
benefits.