Agrotechnology

Assessment of soil quality and resilience in semiarid tropical region of India

2^nd International Conference on Agricultural & Horticultural Sciences

Radisson Blu Plaza Hotel, Hyderabad, India February 03-05, 2014

Uttam Kumar Mandal, K Venkanna, K L Sharma and B Maji

Accepted Abstracts: Agrotechnol

Abstract:

Subsistence agriculture under rainfed conditions and declining or stagnant yields on irrigated farmland has raised concerns about resource management and long-term sustainability in the subtropical, semiarid region of India. Soil quality assessment has been recognized as an important step toward understanding the effects of land management practices within an agro-ecosystem. A soil quality index (SQI) was determined for soils collected from different land use system of Nalgonda and Warangal District of Andhra Pradesh of India. Total 22 physical, chemical and biological properties of soil were analyzed for all the soil samples. The surface map of soil properties was prepared through ordinary kriging interpolation techniques using geostatistical tools of Arc-GIS software. To determine the SQI, minimum data (MDS) of indicators were chosen using Principal component analysis as well as based on contribution of soil parameters to soil function through expert comments. The MDS were converted to score based on soil function and the indicator scores were integrated to an index of soil quality. A multiple regression analysis showed that there was significant dependence between goal variable i.e., yield with SQI. Also there was good relationship (r 2 =0.596) between two procedures of calculating SQI. Calculated SQIs resulted in the order of these land use systems: castor < Intercrop < Redgram < sorghum < cotton < maize < fallow < rice. Irrigated systems had better soil quality than areas where rainfed agriculture was practiced. Among the different soil order, Vertic Inceptisols and Vertisols had highest SQI followed by Inceptisols and Alfisols. A biological resilience of soils was also studied based on substrate induced respiration after heat stress. These results indicated that good soils having higher soil quality indices were also productive and have higher resilience capacity.