TITLE:
Factors Affecting SOC and NPK in the Rangeland, Forest and Agriculture; Case Study Halashi Catchment, Kermanshah, Iran
AUTHORS:
Shohreh Abdolmohamadi, Alireza Ildoromi, Mosayeb Heshmati
KEYWORDS:
Halashi Catchment, Soil Nutrients, Organic Carbon, Tillage Practice
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.5 No.13,
December
28,
2017
ABSTRACT: Land use change causes soil disturbance and thereby considerable soil nutrients depletion and environmental impacts. This research was conducted in Halashi catchment, Kermanshah, Iran to compare the variation of soil NPK and SOC in Agricultural Lands (AL), Rangelands (RL) and Forest lands (FL). The coverage of ground surface including plant crown, stone and litter was estimated in field by using quadrate plot (1 m2). Soil sampling and the analysis were carried out for each land use during April and May, 2015. Inter-rill, rill, gully and landslide were found as the dominant erosion features. The ANOVA analysis explored no considerable differences for soil texture, pH and Electrical Conductivity (EC). High clay and silt content induced clayey and silty soil that means Soil Organic Carbon (SOC) level in the AL, RL and FL were 1.14%, 1.45% and 2.13%, respectively, showing significant (p ≤ 0.05) different from each other among them. The respective values of total N in the AL, RL and FL were 0.14, 0.14 and 0.18 mg/kg, indicating significant decrease in the AL and RL. The respective mean avails P and exch. K in the AL, RL and FL were 15.72, 11.44, 11.38; 342.5, 375.0 and 374.5 mg/kg. Crop residues burning and tillage practicing cause depletion of SOC and NPK in AL, while as compared with FL, lower vegetation canopy and litter in the RL promotes soil nutrients and SOC lost due to overgrazing and converting to rain-fed lands. As a conclusion, rangeland was the intermediate site in terms of soil nutrient and SOC stock in the Halashi.