Evaluation on living organisms and their effects on soil fertility maintenance

Abstract

Soil is a habitat of the most diverse assemblages of living organisms. Living organisms in the soil environment includes bacteria, fungi, protozoa and micro and macro flora and fauna which contribute to the maintenance and productivity of agro-ecosystems. These organisms are involved in major soil process, such as nutrient cycling, biological pest control, and stabilization of soil aggregates and mixing of organic and mineral substance, formation and maintenance of soil structure and degradation of agrochemicals and pollutants. These activities positively influence the physicochemical properties of soil and consequently soil fertility and quality.  But in the present day high intensity agricultural production systems, more emphasis is placed on application of fast reactive chemical fertilizers, pesticides and herbicides leading to imbalance in the sensitive soil ecosystem, decline and deterioration in soil fertility and environment. This decline in soil fertility and inadequate response of chemical fertilizers (i.e. inputs) in terms of the output on account of deterioration in soil health is recognized as a major problem of recent times. So interest in maintenance of soil ecosystems and monitoring of soil health is growing. As the biological activities of the soils are intimately linked with soil fertility maintenance and productivity, sound understanding of various aspects of these soils flora and fauna in the maintenance of soil fertility in crop production systems and clean-up of environment is vital. Effective ways of promoting this microbial activity in agro-ecosystems include conservation tillage, crop rotation, proper nutrient management and application of organic manure. These processes should be practiced to foster the development of healthy and diverse communities of living organisms, improve soil health and food/crop production. Therefore the paper reviews on various living organisms and their effects on soil fertility maintenance.