Can glomalin content be used as an indicator for erosion damage to soil and related changes in organic matter characteristics and nutrients?

Abstract

Erosion is a serious global problem for agricultural land and agroecosystems in general. In the Czech Republic (CZ) erosion affects approximately two-thirds of total agricultural land. In order to evaluate the influence of erosion processes on soil properties, besides traditional parameters relating to soil organic matter, we also focused on glomalin as a product of mycorrhizal fungi and on spores of such fungi. The aim was to verify the sensitivity of this parameter to changes in the soil environment as a result of soil degradation, how it correlates with other soil characteristics, and how useful it is for indicating changes in soil properties. The research was carried out on 48 localities in erosion-threatened areas of Southern Moravia, CZ. Erosional, depositional and control (source) sites located on different slopes were selected using erosion-deposition models. Most statistically significant differences were recorded between erosional and depositional sites, the latter showing higher concentrations in both glomalin and characteristics relating to soil organic matter and content of nutrients. Comparison between source and erosional sites also showed statistically significant differences – higher values of both glomalin and characteristics relating to the quantity and quality of soil organic matter were found in source areas. Moreover, we also found statistically significant differences in the number of arbuscular mycorrhizal fungi (AMF) spores. On the other hand, no statistically significant differences in selected nutrients were found between control and erosional sites. Within our research, source areas did not differ significantly from those of deposition. In evaluating all results, strong correlations were found especially between glomalin and the quantity and quality of organic matter. It was in relation to glomalin that the most correlations were found to the other tested parameters. Our results suggest the possibility of using glomalin values in determining changes in soil properties during degradation processes, e.g. soil erosion.