The Effect of Land use Change on Some of the Physical and Chemical Properties of Soil (Case Study: Semeskande Area of Sari)

Since vast areas of forest lands have been changed in their usage in Mazandaran province in the past decades، this study examined the impact of changing in usage of forest lands in to the agricultural rain-fed lands (canola)، paddy lands and citrus gardens on some physical and chemical properties of soil in the Eastern part of Sari، Iran. For this purpose، four repetitions from each land use were sampled from 2 depths of 0-20 and 20-50 centimeters as factorial design in complete randomized block pattern. Results showed that land use change causes increase in bulk and particular density، the content of bulk density، which in depth، was more than that in surface layer. The most percentage of silt، clay and sand particles was observed in forest، paddy lands and garden usage، respectively. Change in usage caused decrease in water holding capacity and residual moisture. The most percentage of aggregates stability was found in forest and paddy lands. The highest amount of porosity and previous moisture was observed in paddy lands. Land use change caused an increase in soil reaction which increases with depth too. Land use change caused a decrease in organic carbon، the most percentage of which was 2 percent related to forest lands and the lowest percentage of which was 0. 72 percent which was related to rain-fed lands. The lowest available phosphorus was related to rain-fed lands too and the most amount of electrical conductivity was related to paddy lands.