A broad-scale assessment of the effect of improved soil management on catchment baseflow index

作者：Holman I P^*; Hess T M; Rose S C

来源：Hydrological Processes, 2011, 25(16): 2563-2572.

DOI：10.1002/hyp.8131

• compaction
• resilience
• recharge
• flooding
• soil management
• climate change

Although the importance of sustainable soil management is recognized, there are many threats to soils including widespread soil structural degradation. This reduces infiltration through the soil surface and/or the percolation of water through the soil profile, with important consequences for crop yields, nutrient cycling and the hydrological response of catchments. This article describes a broad-scale modelling approach to assess the potential effect that improved agricultural soil management, through reduced soil structural degradation, may have on the baseflow index (BFI) of catchments across England and Wales. A daily soil-water balance model was used to simulate the indicative BFI of 45 696 thirty-year model runs for different combinations of soil type, soil/field condition, land cover class and climate which encapsulate the variability across England and Wales. The indicative BFI of catchments was then calculated by upscaling the results by spatial weighting. WaSim model outputs of indicative BFI were within the 95% confidence intervals of the national-average BFI values given for the Hydrology of Soil Type (HOST(dagger)) classes for 26 of the 28 classes. At the catchment scale, the concordance correlation coefficient between the BFI from the WaSim model outputs and those derived from HOST was 0.83. Plausible improvements in agricultural soil/field condition produced modest simulated increases of up to 10% in the indicative BFI in most catchments across England and Wales, although for much of southern and northern England the increases were less than 5%. The results suggest that improved soil management might partially mitigate the expected adverse effects of climate change on baseflow to rivers. Healthy, well-functioning soils produce many additional benefits such as better agricultural yields and reduced pollutant movement, so improved soil management should provide win-win opportunities for society, agricultural systems and the environment and provide resilience to some of the expected environmental impacts of climate change.

• 出版日期2011-7-30