Managing Organic Matter Content for Restoring Health and Ecosystem Services of Soils of India

摘要

Soil health refers to its capacity to perform ecosystem services (ESs) as a living entity comprising of diverse flora and fauna. Soil organic matter (SOM) content, being an energy source and habitat for biota, is an important determinant of soil health. Through its impact on soil physical, chemical and biological properties, SOM content and its dynamics also determine numerous ecosystem services essential to human wellbeing and nature conservancy. However, SOM content in agricultural soils in India is often below the critical limit of -2% in the root zone because of widespread use of extractive farming practices, low input of organic fertilizers, and prevalence of soil degradation by erosion, salinization and other processes. Thus, agronomic productivity, water quality, and renewability, soil biodiversity and other ESs have been jeopardized, and several disservices (i.e., eutrophication of water, pollution of air, accelerated erosion, emission of greenhouse gases) are caused by poor soil health. Thus, there is an urgent need to restore SOM content, as well as enhance and sustain soil health through adoption of recommended management practices (RMPs). Afforestation of degraded soils, conversion to a restorative land use, and adoption of site-specific RMPs are critical to enhancing soil health. Some RMPs include conservation agriculture (CA), agroforestry, balanced input of fertilizers based on strategies of carbon-centric integrated nutrient management, nutrition-sensitive agriculture, and use ofcover cropping and complex systems. Incentivization through payments for ESs (PESs) by policy intervention is important for promoting adoption of RMPs. Soil scientists and agronomists must facilitate translation of science into action by communication with policy makers, land managers, and the general public. Soil science and environmental education must be included in the curricula at all levels (from primary and secondary schools to undergraduate and graduate courses). Religious organizations may alsobe involved in promoting stewardship of soil and other natural resources, and in advancing the concept of 'Rights-of-Soil.' Transformation of the fertilizer sector, with an emphasis on efficiency rather than rate of input, necessitates focus on restoration of soil health through increase in soil organic carbon content in the root zone by adoption of RMPs such as CA, agroforestry, and CNPK rather than NPK.