A Study of Influence of Vegetation on the Law of Soil Nutritive Elements Distribution in Estuary Wetlands

摘要

Through gauging the contents and distribution of nutritive elements such as,C,N,P and K in soil under different vegetation covers (vegetation living body,PA; vegetation dead body,PD; bare mudflat GT) in the estuary wetland,this paper analyzes the influence of vegetation covers on the law of nutritive elements distribution in soil and their metrological features.The results showed that the content of nutritive elements in the soil of PA sample plot was in general at a relatively high level.The contents of TN,rapid-available nitrogen and total potassium showed the law of PA ＞ PD ＞ GT; the TP content showed the law of PA ＞ GT ＞ PD;and the rapid-available phosphorus and rapid-available potassium showed the law of PD ＞ PA ＞ GT.Under the three types of vegetation covers,the contents of TN,TP,rapid-available potassium,and rapid-available phosphorus in the soil profile decreased first before they increased along with the depth downward,mostly taking the area of 20 cm deep as the turning point; the TN content gradually increased in general along with the depth downward; the law of change in the contents of potassium and rapid-available nitrogen was not significant,the area of 20 cm deep remaining the turning point.The RCN in soil showed,PA(13.98) ＜ PD (14.04) ＜ GT(18.03),the RCP showed PA(67.39) ＞ PD(61.74) ＞ GT(51.27),and the RNP in soil showed PA(4.37) ＞ PD(3.87) ＞ GT(2.80).Vegetation covers resulted in the soil showing the restriction of a low N and the restriction of a high P.