Technologies and Mechanisms for Improving Soil Fertility: A Review

Intensive agriculture and other anthropogenic activities have led to soil degradation in many regions across China. Improving soil fertility and restoring soil functions is important to maintain sustainable agricultural production and safeguard food supply in China. In this paper, we systematically review the methods and technologies developed over the past decades to improve soil fertility, which includes the concept of soil fertility, index and methods for evaluating soil fertility, the relationship between soil fertility and crop yield, as well as the prospects of soil fertility improvement. In particular, we analyze and discuss the applications of various organic materials including processed biochar and commodity organic fertilizers for improving soil fertility and their efficacy for different soils. We conclude that establishing standards of biochar and organic fertilizers and their application as soil improvers will be an important research area for long-term improvement of soil fertility.