Studies on Soils and Potential for Soil Erosion in the Sheep Farming Area of South Greenland

Abstract

Field data are lacking in studies of soil erosion in South Greenland and its relationship to soil processes and soil-forming factors. The main soil-controlling factors are climate, vegetation and other organisms, parent material, relief, time, and the influence of man. The potential for soil erosion is primarily expressed through the balance between the factor vegetation and the other soil-forming factors. The local conditions point to climatic or topographic gradients as the controlling agents of soil erosion when and if the vegetation cover collapses. The rate of soil erosion is dependent upon the existing soil, the parent material, temperature (length of growing season), and soil moisture. The latter two factors are especially decisive for controlling the vegetation cover. The soil profile is a snapshot of the effect of soil forming processes since the retreat of the ice about 9000 yr ago.

The studies to date have shown that a two-sequence profile is found in most places. The top of the first sequence corresponds to a date of A.D. 895–940, which is that of the Norse settlement and indicates strong soil erosion in the area during that period.

The Norsemen settled in South Greenland in 985 and the area was deserted in late 1400. No exact knowledge exists about their fate, neither why they left nor what became of them. Was the extinction a result of climatic oscillations related to overgrazing and soil erosion? This subject is reviewed as well as modern sheep farming starting in 1915 with an introduced sheep race from Iceland. Large oscillations of the stock through the years indicates problems in relation to climate as well as to vegetation. In 1983 studies on the ecological balance of the area were initiated. This report is one of the first results of this interdisciplinary research focusing on soil erosion studies.