besides the agricultural region is expanding to the north and thus the arid steppe zone of eastern mongolia is pushing the forest steppe zones to the north as a result the size of the high mountain and forest steppe zone is decreasing and the size of the steppe and desert steppe zone is increasing several principal processes are likely to lead to a decline in agricultural productivity as a result of land degradation these include reduction in effective rooting depth loss of plant nutrients and soil organic carbon loss of plantavailable water loss of arable land area and damage to seedlings