Precipitation–soil water chemistry relationship: case study of an intensively managed grassland ecosystem in southwest England

Abstract

Abstract Environmental assessments typically require fine- or high-resolution datasets, example of which the Environmental Change Network (ECN) provides. This study has therefore taken advantage of the free access to the datasets to investigate temporal characteristics of precipitation and soil water chemistry, and relationship between the concentration of selected chemical variables in precipitation and soil water at 0–10 cm and below 10 cm depths based on data availability. The aim was to determine whether observations from the ECN data support results from the previous hypothesis on dominant run-off mechanism at the study area. Method of analysis involves inferential statistics and wavelet transform plot of selected physico-chemical variables for six (2010–2016) years. Results showed that most of the selected chemical variables exhibited low coefficient of determination in the relationship of their concentration in precipitation and soil water. Relatively linear relationships, however, occurred in the values of conductivity, Cl−, Ca2+, alkalinity and Mg2+ between the 0–10 cm and below 10 cm depths, indicating mixing of soil water at both soil zones. Inference from the results suggests a possible significant role of pre-event water or geological influence on soil water chemistry. The study affirms the hypothesis that saturation overland flow dominates areas underlain by Halstow soil series in the area.

Keywords

• Ion balance
• Precipitation chemistry
• Run-off processes
• Soil water chemistry
• Wavelet analysis