CRC - Agroecosystems: Soils, Climate, Crops, Nutrient Dynamics and Productivity
|Publication Date:||4 December 2013|
Historically, seeds for agricultural cropping were sown in the Fertile Crescent region of Middle Eastern Asia some 8-10,000 year ago. Since then, crops and human beings have evolved together. Several crop species were domesticated and cultivated during the Neolithic Period. In due course, cropping systems were refined and mildly intensified. During the medieval period, human ingenuity and man's inquisitiveness led him to migrate to different parts of the globe. This induced the spread of several crop species and facilitated formation of cropping belts across different continents. Soon, vast stretches of crops were developed and agronomic procedures were consistently refined to enhance productivity. Agroecosystems that were generated were either subsistent or intensively nurtured.
In the past century, agroecosystems were markedly dynamic with regard to crop species, genetic stocks, fertilizer/nutrient turnover, and productivity. Agroecosystems that supplied food grains and other products to large populations of humans and domesticated animals were preferentially intensified. Nutrient supply, crop genetic stocks, and facilitation of irrigation were the key factors that induced formation of productive agreocosystems in different parts of the world. Globally, we may encounter agroecosystems that are at different stages of evolution, development, sustenance, and productivity. Several of them could be still developing, others may have reached zenith, and yet others could be in process of deterioration or replacement. Such dynamics are induced by natural and man-made factors. Whatever may be the natural state of agroecosystems, we need to appreciate that each agroecosystem, small or large, has its say in terms of human nutrition and energetic functioning.
Agroecosystems that we have inherited and as we perceive them today are actually marvels created on earth's surface through human endeavor over a few millenniums. We have understood and accrued a large body of knowledge about them. Yet, we have too many things to investigate and perhaps control to our own advantage, of course, without deteriorating natural resources and our environment. Today, an entire posse of agroecosystems on the globe feeds over 7 billion human species and innumerable farm animals. We have to strive to modify these agroecosystems to feed a larger populace in the future.
Agroecosystems occupy a third of the global land surface. They are composed of a variety of soil types, crop species, and water resources. Major cereals such as wheat, maize, rice, few legumes, cash crops and plantations dominate the agrarian zones. Pastures and forage belts occur conspicuously in different continents.
The central theme of this book is agroecosystems that flourish in different continents of the world. Major focus is on the ingredients such as soils, climate, crops, nutrient dynamics, and productivity. There are three sections in this volume. The first section presents two chapters that support vast crop belts. In addition, there are 21 chapters that deal with the wide range of agroeocsystems that thrive on the globe. Detailed descriptions about crop species, their origin, spread, genetic aspects, agroclimatic requirements, expanse and productivity are available for 32 important crops. The second section presents principles that drive crop growth, nutrient dynamics, and ecosystematic functions within any agroecosystem. There are seven chapters that deal with various aspects of nutrient dynamics in an agroecosystem. Several natural and man-made factors regulate development, sustenance, and productivity of agroecosystems. The third section presents seven chapters that influence agronomic practices and factors such as soil microbes, organic matter, crop genetic nature, irrigation, weeds, and cropping systems that affect productivity of agroecosystems.
Over all, this book on agroecosystems provides detailed information on soils, crops, general principles that govern nutrient dynamics, and factors that affect productivity. It is useful to professors, researchers ,and students dealing with agriculture, ecology, and geography. It serves as a general reference book for all those interested in understanding our own nature and surroundings.