Environmental effects of the succession vegetation of lower subtro-pical zone in Southern China

Abstract

This study deals with the capacity for nutrient conservation, the balance of carbon and oxygen as well as the buffering of acid rain in the succession of vegetation of lower subtropical zone of southern China. The results show that: (1)N,P,K contents of plants of a 100 year old monsoon evergreen broad-leaved forest were 12-39 times those of the grassland and fernland. They were 12-16 times those of the shrubland. Its N,P,K contents of litter were 11-36 times those of grassland and fernland,and 3.1-5. 2 times that of the shrubland. The mass of N,P,K in net primary production of 30 year old monsoon evergreen broad-leaved forest were 1. 9-5.1 times those measured in the grassland,fernland and shrubland. (2)Carbon content of plants of the 100 year old monsoon evergreen broad-leaved forest was 13-49 times those of in the grassland,fernland and shrubland. The amount of fixed carbon in the 30 year old monsoon evergreen broad-leaved forest was 2. 3-3. 4 times those of the grassland,fernland and shrubland. The amount of oxygen made in the former was,obviously,also greater than in the latter. (3)Mean pH values of throughfall from the fernland, shrubland and monsoon evergreen broad-leaved forest were 1. 13,1. 03 and 1. 90 units higher than that of rainfall. The buffering capacity of the monsoon evergreen broad-leaved forest for acid rain was significantly higher than that of the fernland and shrubland. (4) The environment effects of vegetation could be increased by succession. It is very helpful for improving the eco- environment if the grassland,fernland and shrubland are changed to monsoon evergreen broad-leaved forest by succession.

This study deals with the capacity for nutrient conservation,the balance of carbon and oxygen as well as the buffering of acid rain in the succession of vegetation of lower subtropical zone of southern China.The results show that:(1)N,P,K contents of plants of a 100 year old monsoon evergreen broad leaved forest were 12～39 times those of the grassland and fernland.They were 12～16 times those of the shrubland.Its N,P,K contents of litter were 11～36 times those of grassland and fernland,and 3.1～5.2 times tha...

研究华南南亚热带不同演替阶段植被对养分保护、碳氧平衡和对酸雨的缓冲作用的结果表明: 100 年生季风常绿阔叶林植物N、P、K 贮量是草地和芒萁群落的12 ～39 倍, 灌木林的12～16 倍; 死地被物N、P、K 贮量是草地和芒萁群落的11～36倍, 灌木林的3. 1～5. 2 倍. 30 年生季风常绿阔叶林净初级生产量的N、P、K 贮量是草地、芒萁、灌木群落的1. 9～5. 1 倍. º 100年生季风常绿阔叶林植物碳贮量是草地、芒萁、灌木群落的13～49 倍. 30 年生季风常绿阔叶林植物碳净固定量是草地、芒萁、灌木群落的2. 3～3. 4 倍, 前者的氧释放量也明显大于后者. » 芒萁、灌木群落和季风常绿阔叶林穿透雨的平均pH 值比降雨pH 值分别高1. 13、1. 03 和1. 90 个单位, 季风常绿阔叶林对酸雨的缓冲能力明显高于芒萁、灌木群落. ¼正向演替可加强植被的环境效应, 让草地、芒萁、灌木群落演替成为季风常绿阔叶林, 有利于区域生态环境的改善.