The impact of permanent gullies on present-day land use and agriculture in loess areas (E. Poland)

The socio-economic effect of the occurrence of specific forms of relief, is a significant research problem in applied geomorphology. The objective of this study was to assess the impact of permanent gullies on land cover and agriculture within the loess areas of Eastern (E.) Poland. We analyzed the relationships between an area consisting of gullies and selected environmental and socio-economic indices. We used the following statistical methods: Pearson's linear correlation, ANOVA, PCA and cluster analysis. It was found that districts with a similar gully density are characterized by the occurrence of a similar set of economic characteristics found within agriculture (cluster analysis). The most distinct impact of the occurrence of gullies on the potential of agriculture was observed when gullies covered more than 2% of the district. We identified the relationships between the area covered by gullies and present-day forest cover (Pearson correlation index 0.5), changes in the forest cover in the 20th century (0.7), the area of landscape parks and reserves (0.8) and the share of big farms (−0.5). Weak negative correlations occurred between the gully area and the economic aspects of agriculture (indices from −0.2 to −0.4). The correlations between the area of gullies, area of forests and share of farms larger than 20ha were confirmed by ANOVA. The PCA method showed a negative correlation between the area of gullies, the share of arable lands and the share of farms with good prospects. A positive correlation was found in the case of protected areas, steep slopes and forests. In the future, gullies may turn out to be a challenge to the development of efficient agriculture; they are an obstacle to land consolidation and farm enlargement. Areas characterized by a high density of gullies require special spatial management to reduce negative economic effects.