Type Classification Of The Broad-Leaved Forest In Upper Slope And Bamboo Plantation In Lower Slope Compound Ecosystem

Moso bamboos(Phyllostachys edulis) are important forestry plants in southern China, with substantial roles to play in regional economic and ecological systems. The Broad-Leaved Forest in Upper Slope and Bamboo Plantation in Lower Slope(BUBL) has become a common forestry management strategy in southern China, and it is fundamental to elucidate the interactions between broad-leaved trees and moso bamboos and to choose the optimal proportion of broad-leaved forest for ensuring the sustainable provision of ecosystem services. We did explored the influences of the upper broad-leaved forest together with climatic factors, terrain factors and soil factors on the effective productivity of moso bamboo(i.e. those with significant economic value). Then we divided the types of the BUBL compound ecosystem and evaluated the productivity of each type. The main conclusions are as follows:(1) Climatic factors have significant impacts on the mean diameter at breast height(DBH)of moso bamboo. There is a strong correlation between climate and altitude, making it appropriate to use altitude instead of climatic factors to analyze the effects of climatic factors on bamboo productivity. Climatic factors and altitude have extremely strong correlation with latitude and longitude. Some regularity was found about the distributions of the DBH of moso bamboo predicted by the value of latitude and longitude. The region with maximum effective productivity of moso bamboo is mainly concentrated in two parts of southern China: one is at the border of Jiangxi and Zhejiang provinces and another is at the border of Hunan, Hubei and Jiangxi provinces, with the latitude and longitude range, 113.5°-114.5° E, 28.0°-29.0° N and116.5°-119.5° E,28.0°-29.0° N.(2) The broad-leaved forest in the upper slope has a strong influence on the effective productivity of moso bamboo. The importance of these variables to bamboo productivity is,respectively, slope(25.9%), the proportion of broad-leaved forest(24.8%), elevation(23.3%),gravel content by volume(16.6%), slope location(8.3%), and soil layer thickness(1.2%).Highest productivity is found on the 25° slope, with a 600 m elevation, and 30% broad-leaved forest. Bamboo’s diameter at breast height follows a Weibull distribution.(3) Under the BUBL management pattern, the four factors affecting the effective productivity of moso bamboo include slope, the proportion of broad-leaved forest, elevation, and gravel content by the volume respectively.(4) We divided the BUBL compound ecosystem into four types according to the classification system of forest site in China and the dominant factors.(5) Research on the influence of the BUBL management pattern on bamboo productivity shows that compared with pure bamboo forest, the DBH and height of moso bamboo under the BUBL management pattern are higher and the density, evenness and leaf area index(LAI) are more reasonable, indicating that the BUBL management pattern canimprove the productivity of moso bamboo.In summary, under the BUBL management pattern, the broad-leaved forest in the upper slope can have a strong influence on the effective productivity of moso bamboo, ranking only after slope and before elevation. These factors should be considered in future management practice.