Soil and environmental management

Abstract

Climate change is a variation in atmospheric properties due to natural and human activities over a long period of time. In the last few decades, there was a significant change in the gaseous composition of earth's atmosphere, mainly through increased energy use in industry and agriculture sectors, viz. deforestation, intensive cultivation, land use change, management practices, etc. These activities lead to increase the emission of carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), etc., popularly known as the "greenhouse gases" (GHGs), and rise up the temperature. These GHGs cause regional and global changes in the climate-related parameters such as rainfall, soil moisture, and sea level. Intergovernmental Panel on Climate Change (IPCC) projected temperature rise from 0.5 to 1.2 ° C by 2020, 0.88 to 3.16 °C by 2050, and 1.56-5.44 °C by 2080 for India. To mitigate this climate change, among the different means, soil is also one of the key components of the agricultural production system, and it needs to be relooked in the view of the environment. Soil not only acts as a sink for GHGs but also as a source from agriculture. In this regard, concerted efforts are necessary for adverse climate change impact to reduce the vulnerability of agriculture. To meet out these issues, sources and mitigation options for individual gases from the soil are discussed in this chapter. Sources of CH4 emission are due to microbial decomposition of soil organic matter (SOM) under the submerged condition, burning of crop residue, and the enteric fermentation. The N2O is through fertilizers by the process of nitrification and denitrification. The major carbon (C) sources are tillage, burning of crop residue, and fossil fuel combustion. To overcome the emission of GHGs from the soil, the nature of the release of individual gas and its specific management can give an idea of sustaining soil health to safeguard the environment. Hence, reducing these GHGs emission from the soil through light to overcome the climate change effect. Reduction of CH4 gas mainly from rice can be done by the adoption of intermittent irrigation, planting methods, fertilizer type, etc. Nitrification inhibitors from plant-derived organics such as neem oil, neem cake, and Karanja seed extract could also reduce the N2O emission. Also, the demand-driven nitrogen (N) application using a leaf colour chart (LCC) reduces N2O emission. By using legume crops in rotation helps to reduce the N2O emission besides fixing long time C in the belowground. To reduce CO2 emission from the agriculture, sequestering C through agroforestry system, conservation agriculture, perennial crops, etc. could be the effective strategies for assimilating and storing C for a long time in soil.