Soil Fertility Status in and Around the Tea-Garden Belt of Belwa, Kishanganj District, Bihar, India

Soil is one of the most significant ecological factors, on which plants depend for their nutrients, water and mineral supply. Pesticides, fertilizers and agrochemicals applied by tea growers are largely retained by the soil. They undergo degradation in soil through the processes of biodegradation, chemical degradation or photochemical reactions. Therefore, environmental health aspects of soil deserve serious attention in near future. The aim of the present research work is to monitor the status of the soil fertility in and around tea garden belt of Belwa, Kishanganj district, Bihar, India. Thirty soil samples were collected from top soil (1-15 cm) in and around (paddy field) of five selected tea gardens during 2014 - 2015. Soil samples were analyzed for pH, EC, OC (%), BD, macronutrients and micronutrients. Results revealed that, pH of soil varied from 4.4-5.7, which suggest that soil in the study areas was acidic. The total organic carbon ranged from 0.76-1.81(%) and available N, P and K content varied from 255.25 to 431.21; 9.32 to 31.32; 45.98 to 182.81 kg/ha respectively. Mn, Fe, Cu and Zn concentrations varied from 130.12 to 412.71; 91.23 to 278.2; 14.99 to 29.67; 22.12 to 46.23 and mg/kg respectively. Correlation study revealed that macronutrient and micronutrient showed positive correlation with pH and organic carbon (%). Moreover tea growers and farmers of the study areas applied higher amount of N-based fertilizers then P and K based fertilizers causing a decrease in soil available P and exchangeable K. Therefore this research work will be helpful in reconciling of local and scientific knowledge among tea growers and farmers which may be the most important step to obtain satisfactory level of crop production and maintenance of soil fertility and productivity.