Weather Extremities and Soil Processes: Impact of Excess Water on Soil Structure in the Southern Great Hungarian Plain

Abstract

With global climate change, the frequency of extreme weather events, which also affect soil properties, has increased. Hungarian agriculture was stricken with drought in the 1990s, whereas inland excess water has caused damages in 2000, 2006 and again in 2010. According to multivariable correlation tests, in addition to hydrometeorological, geological and topographical factors, soil properties also influence the formation of excess water, which can, in turn, modify soils (bring about hydromorphic characteristics or physical degradation). The aim of the present study is to reveal the interactions between inland excess water and soil properties illustrated by a case study carried out on a fertile chernozem soil after the extensive excess water coverage of 2010. Three excess water patches were identified for analysis from multitemporal Landsat images in the study area and were connected in a southwest-west–northeast-east aligned, 700-m-long, catena. In July 2011, topsoil samples were collected along this catena at 50-m intervals from three depths, to compare the particle-size distribution and agronomical structure of soils of temporary excess water with those not affected by it. In order to create a multilayer map from soil compaction data, penetration resistance and relative soil moisture were measured at a depth of 60 cm at 117 points in the 45-ha study field using a 3 T System hand penetrometer. The results call attention both to the physical soil degradation caused by excess water and to the risk of erosion due to inadequate tillage or cultivation practices.KeywordsExcess waterInundationSoil structurePenetration resistanceChernozemHungary