Effect of Land Use and Slope Position on Agronomic Productivity of a Calcareous Soil

摘要

The effects of land use and slope position on soil properties and agronomic productivity were studied on a greenhouse experiment for a set of calcareous soil samples taken from a semiarid region of Iran. Eight soil samples were collected from four slope positions along a landscape from two adjacent land uses of rangeland and dry farmland. Soil samples were analyzed for their physical and chemical properties and yield and yield components of wheat were measured in the greenhouse. Soil had higher fertility and quality on the dry farmland than the adjacent degraded rangeland. The results indicated that yield components of wheat were higher in the dry farming land compare to the degraded rangeland, and in the lower slopes compared to the upper slopes. The effects of land use and slope position on agronomic productivity influenced by water supply, the true impact of soil degradation induced by land use and slope position on soil productivity was overshadowed under limited water application. While both chemical and chemical+manure fertilizations could enhanced soil agronomic productivity, the effects of chemical+manure fertilization was higher especially for more degraded soils of rangeland. Water stress reduced fertilizer efficiency especially for chemical fertilizers.