Innovative Organic Fertilizers and Cover Crops: Perspectives for Sustainable Agriculture in the Era of Climate Change and Organic Agriculture

Abstract

Anthropogenic activities have resulted in land desertification in various regions of the world, leading to the degradation of critical soil characteristics such as organic matter (OM) content, nutrient stock, and prevailing biodiversity. Restoring such degraded soils through organic matter amendments and diversified crop rotations is thus an intrinsic part of organic farming. This review discusses a wide range of organic farming impacts on soil health and crop productivity by focusing on organic fertilizers and crop diversification. Conventional fertilizers were considered vital for agricultural production to harvest high crop yields. Nevertheless, they are now deemed as environmentally hazardous and an obstacle to sustainable agroecosystems due to intensive chemical inputs that damage the soil over time and have long-lasting impacts. Conventional fertilization results in nutrient depletion, loss of microbial diversity, organic matter reduction, and deterioration of physical characteristics of the soil. Conversely, organic fertilization makes use of naturally existing resources to improve soil health. Organic amendments such as biochar, manure, and fermented grass improve soil’s physical, chemical, and biological properties and promote the growth and diversity of beneficial soil microorganisms—important in nutrient cycling and soil stability. They facilitate the uptake of nutrients, hinder crop pathogen growth, mitigate heavy metals, and decompose xenobiotic organic substances. Moreover, growing cover crops is also a major strategy to improve soil health. Diversified crop rotation with combinatorial use of organic fertilizers may improve soil health and agricultural yields without any detrimental impacts on the environment and soil, ensuring sustainable food production, safety, and security. This integrated approach contributes to minimizing the use of chemical fertilizers and their effects on environmental health. It also contributes to reducing agricultural inputs along with enhancing OM, soil microbial diversity and biomass, nitrogen fixation, and carbon sequestration. Therefore, cover crops and organic fertilization may offer sustainable agroecosystems and climate change mitigation.