Abstract
We aim at clarifying land environmental condition on the basis of the intensity of predominating geomorphic agents, and figuring out current agricultural management and acceptance process of environmental policies, in the eastern margin of the Ulan buh Desert. Geomorphologically, aeolian dune area continues to expand since about 8 ka, when the youngest fluvial terrace surface emerged along the Yellow River, and migrating rate of the dune front is estimated to be approximately 10-1-100 m/yr during the past several thousand years, and 100-101 m/yr in places since the 1960s. Because the terrace surface was almost entirely embedded under aeolian sand layer as a result of the dune expansion, the agricultural lands are exclusively located on the flood plain, where groundwater level is extremely shallow and topsoil salinization tends to occur.
In the mid-1990s, people began to introduce sunflower production in the study area, because of its higher cashability and tolerance for dryness, and it became a new major income source, instead of the former stock farming, affected by the shrinkage and disappearance of grassland on account of the dune expansion. Due to continuous cultivation of the sunflower, they are in need of keeping a balance on land use, between risks in environmental resource, namely, decline of yield and soil fertility, disease and insect damages, overuse of chemical fertilizers and pesticides, and salinization, and farmland maintenance by winter-flooding in sunflower fields;however, the balance currently seems to be lost by degrees. Grazing prohibition implemented as one of environmental policies, had stronger characteristics of being income security, and therefore, in order to maintain the sustainability of environmental resources, operation of the policy taken into account both land environmental condition and people’s livelihood strategy, should be necessary.
