The Effect of Slope Aspect on Soil and Vegetation Characteristics in Southern West Bank

Abstract

This study aims to investigate the effect of south and north slope aspect on soil properties and vegetation characteristics (plant cover, biomass, and density) in a semi-arid area in the southern part of the West Bank. The results indicate that the amount of organic matter, electrolyte concentration (EC), NH4+, available phosphorus and soil moisture content were significantly higher in the north aspect compared to the south aspect. However, pH and CaCO3 were significantly higher in the south than the north aspect. The results of vegetation characteristics showed that total dry biomass, density and cover were higher in north aspects than south aspect. Forbs dry biomass was significantly higher in the southern slope (67.8 g/m2) than that of the northern slope (46.6 g/m2). While, the total grass biomass was significantly higher in the north aspect (35 g/m2) compared to the south aspect (11.3 g/m2). The results also showed that plant attributes were mainly different at the level of individual plant species. Echinops polyceras, Asphodelus aestivus, and Eryngium creticum are dominant plant species in the south facing slope and they have higher dry biomass by 96 %, 95%, and 88 % compared to the north facing slope. These results show that slope aspect in the arid and semi-arid region have an effect on spatial heterogeneity and distribution of moisture and nutrients resources this effect also is expressed in vegetation attribute between the two aspects.