Assessing the relations among the features of the land cover and of the soil on the soil-water interactions through a functional eco-hydrological indicator

Abstract

Soil Water Repellency (SWR) is an important ecological property that has implications in the soil and water management and is a useful functional eco-hydrological indicator driven by several natural and human factors. In our research we assessed the relationships between SWR and soil properties, broaden the evidence of the influence of land cover on the development of SWR. We also evaluated the relation between SWR and erosion indicators (EI), and we checked the occurrence and severity of distilled water and aqueous ethanol solution repellency before and after the soil samples are compacted (that augmented the soil density in 10%). In the field, we collected superficial soil samples considering the local land cover features, and we assessed the EIs following a pre-established protocol. For evaluating the SWR we used the “drop penetration time” method. Our results show that the soils are mostly neutral (in terms of soil acidity), silt or sandy-textured and chiefly hydrophilic. The texture is an intrinsic soil attribute that primarily influences the relations between soil and water, and the affinity to water is significantly different among the land cover categories. Land cover change induces modifications in the soil surface, and the soil gets more hydrophilic. The EIs helped to evidence such changes caused by land cover changes. Compacted soils led them to be more hydrophilic, regardless of the reagent, being this finding still barely reported in the literature.