Impact of Organic Additives on Soil Organic Carbon and Enzyme Activities in Intensive Ginger Agro-ecosystems

Abstract

Organic manure is a good source of nutrients, which enhances soil productivity, increases the soil organic carbon content, enhances the activities of soil microorganisms, and supplies major plant nutrients. Nutrient management is one of the key determinants of crop production. Variability in nutrient additions through fertilisers and organic manures appears to be an influencing factor on soil fertility status and ginger productivity. This study was conducted to assess different magnitudes of organic and inorganic nutrient inputs on soil carbon stock and soil enzyme activities. A survey-based study was conducted.The data obtained was subjected to one-way ANOVA using Excel software version of Windows MS Office -2007. In the Banavasi area of Uttara Kannada, Ginger farmers adopted different nutrient management practices in ginger cultivation were grouped into Local Farmers-1: High OM and High Fertilisers, Local Farmers-2: Low OM and Moderately High Fertilisers and Migrated Farmers: Very Low OM and Very High Fertilisers. Soil samples were collected at two sampling depths (0-15 cm and 15-30 cm) in three groups of ginger farmers’ fields. The mean rainfall of this region is 2500 mm, with up to 103 rainy days in a year. Annually, this region has 25 hot days with temperatures more than 350 C and 124 warm days ranging 30-350 C and remains below 350 C during the rest of the year for about 214 days. The soil organic carbon content was higher in soils of Local Farmers-1 compared to Local Farmers-2: Low OM and Moderately High Fertilizers and Migrated Farmers: Very Low OM and Very High Fertilizers thus, the study revealed that application of organic manures in intensively managed ginger production systems helps to enhance soil carbon stocks and maintain soil biological activities.