Effect of application of fertilizers on soil structure in red soil

Changes in physical structure of red soil were studied under different conditions of fertilizer application.The results showed that the content of ＞1mm mechanical-stable macro-aggregate was increased while the content of ＞1mm water-stable macro-aggregate decreased after red soil was cultivated,but applications of organic fertilizers were beneficial to buffer the decline tendency of content of ＞1mm water-stable macro-aggregate,and to increase total macro-aggregate content of ＞0.25mm.Soil porosity was increased while soil bulk density was decreased after red soil cultivated.Soil capillary porosity was increased by 50%,and soil available water capacity increased by 64% under application of organic fertilizers,while application of chemical fertilizers only increased by 27% and 33% respectively.Meanwhile,there was a significant increase in soil reserving water capacity under application of organic fertilizers,but there was no significant difference between application of chemical fertilizers and uncultivated soil.