Agroecosystems of South India

Book excerpt: Agroecosystems of South India is a unique treatise that deals with the relevance of natural resources, genetic stocks, fertilizers, and agronomic practices on the productivity of agroecoregions. Within the context of this book, an agroecosystem has been defined as a conglomerate of small cropping zones, which may be mono-cropping expanses or intercrops that occur in various geographic regions of South India. South India abounds with several such agroecosystems that encompass field crops, vegetables, cash crops, plantations, and forest species. However, the main emphasis within this volume is restricted to agroecosystems that include major cereals, legumes, and oil seed crops. There are 10 chapters in this volume. The first, on historical aspects, traces important events related to domestication, introduction of crop species, agricultural implements, development of soil fertility and crop husbandry procedures. An introductory chapter on Agroecosystems delineates various agroecoregions of South India. Their classification based on physiography, soils, and climatic parameters have been dealt with in great detail. Descriptions on natural resources such as soils and their fertility conditions; water resources; climatic conditions including precipitation patterns; and crops and their genotypes are available in chapter 2. The impact of soil fertility and nutrient dynamics on ecosystematic functions and productivity of crops in an agroecosystem forms the central piece of discussions within chapters 3 to 9. Historical background, geographical settings, agroclimate, soils, cropping systems, and productivity trends have been provided for each cropping ecosystem. Recent advances and details on aspects of nutrient dynamics, such as soil nutrients, their availability, physico-chemical transformations, nutrient fluxes, inorganic fertilizer supply, organic manures, crop residue recycling, nutrient carry over and nutrient balances/imbalances form the core of each chapter. The impact of beneficial soil microbes such as Rhizobium, Plant Growth Promoting Rhizobacteria and Arbuscular Mycorrhizas, on nutrient dynamics in soil has also been discussed. More recent developments dealing with modeling nutrients in cropping ecosystems, computer based-simulations, precision farming and site-specific nutrient management have been emphasized. Forecasts on the impact of nutrient dynamics on the future course of agroecosystems are also available. Overall, this book is a scholarly edition that aims at providing an excellent exposition of recent developments within various agroecosystems of South India to a global audience. It highlights the importance of soil fertility and nutrient dynamics within agroecosystems to total food grain and fodder production in South India. It will be a useful book to researchers, professors, and students dealing with agriculture, environmental science, ecology, and plant science.