SOIL ANALYSIS: JHARKHAND
INTRODUCTION:
Reliable information on the location, extent and quality of soil and land resources is the first requirement in planning for the sustainable management of land resources. The components of land i.e., soils, climate, water, nutrient and biota are organised into eco-system which provide a variety of services that are essential to the maintenance of the life support system and the productive capacity of the environment. Our land mass is fixed, but the competition among different kinds of uses for this land is increasing because of rapidly rising global population. Therefore, integrated land resource planning and management are required to resolve these conflicts and soil resource survey seems to be a viable means in this process and knowledge of soil fertility status and problems of soils like soil acidity/alkalinity become essential for sustainable land use plan. Soil fertility is an aspect of the soil-plant relationship. Fertility status of the soils is primarily and importantly dependent upon both the macro and micronutrient reserve of that soil. Continued removal of nutrients by crops, with little or no replacement will increase the nutrient stress in plants and ultimately lowers the productivity. The fertility status of the soils mainly depends on the nature of vegetation, climate, topography, texture of soil and decomposition rate of organic matter. Optimum productivity of any cropping systems depends on adequate supply of plant nutrients. GIS is a versatile tool used for integration of soil database and production of a variety of users specific and user-friendly interpretative maps. This further leads to accurately and scientifically interpret and plan some of the aspects like conservation of organic matter, soil reaction (pH) control and fertilization. Keeping in view NBSS & LUP, Regional Centre, Kolkata in collaboration with Department of Soil Science and Agricultural Chemistry, BAU, Ranchi, Jharkhand undertook a project entitled “Assessment and mapping of some important soil parameters including soil acidity for the state of Jharkhand.The major objectives of the project were.
-
Preparation of district wise soil acidity maps
-
Preparation of district wise soil fertility maps (Organic carbon, available N, P, K, S and available Fe, Mn, Zn, Cu and B)
METHODOLOGY:
The base maps of the districts were prepared on 1:50,000 scale using Survey of India toposheets and all the maps were demarcated with grid points at 2.5 km interval. Surface soil samples from demarcated grid points and other related information were collected through field survey. Soil samples were air dried, processed and analysed for pH, organic carbon, available phosphorous and potassium (Page et al., 1982), available nitrogen (Subbaiah and Asija, 1956), available sulphur by using 0.15 percent CaCl2 as the extractant (William and Steinbergs, 1959), available (DTPA extractable) Fe, Mn, Zn and Cu (Lindsay and Norvell, 1978) and available B (hot water soluble) by Carmine method (Hatcher and Wilcox, 1950). The soils are grouped under different soil reaction classes viz extremely acidic (pH<4.5), very strongly acidic (pH 4.5 – 5.0 ), strongly acidic (pH 5.1 – 5.5), moderately acidic (pH 5.6-6.0), slightly acidic (pH 6.1-6.5), neutral (pH 6.6- 7.3), slightly alkaline (pH 7.4-7.8), moderately alkaline (pH 7.9-8.4), strongly alkaline (pH 8.5-9.0) according to Soil Survey Manual (IARI, 1970).The soils are rated as low (below 0.50 %), medium (0.50-0.75 %) and high (above 0.75 %) in case of organic carbon, low (<280 kg ha-1), medium (280 to 560 kg ha-1) and high (>560 kg ha-1) in case of available nitrogen, low (< 10 kg ha-1), medium (10 to 25 kg ha-1) and high (> 25 kg ha-1) for available phosphorus, low (< 108 kg ha-1), medium (108 to 280 kg ha-1) and high (> 280 kg ha-1) for available potassium and low (<10 mg kg-1), medium (10-20 mg kg-1) and high (> 20 mg kg-1) for available sulphur (Singh et. al. 2004, Mehta et. al.1988). Critical limits of Fe, Mn, Zn, Cu and B, which separate deficient from non-deficient soils followed in India are 4.5, 2.0, 0.5, 0.2 and 0.5 mg kg-1 respectively. (Follet and Lindsay, 1970 and Berger and Truog, 1940). The maps for the above mentioned parameters have been prepared using Geographic Information System (GIS) from data generated by analysis of grid soil samples.
Source: Fertilizer and Agriculture Statistics, Eastern Region (2003-2004)