气候变化对中国森林生产力的影响 Ⅰ.中国森林现实生产力的特征及地理分布格局

Impacts of Climate Change on Productivity of Forests in China I. Geographic Distribution of Actual Productivity of Forests in China

本文从生产力与环境关系角度,比较分析了森林第一性生产力的地理分布特征,阐述了层的生产力与环境间的关系以及种生产力与群落结构间的关系。结果表明:森林净生产力,地上部年凋落量随纬度和海拔高度的增加而减少,而凋落物现存量呈相反的变化趋势,森林生产力的地理分布与环境水热条件密切相关;森林生物量无明显的地理规律性变化,但多物种复杂结构的成熟天然林生物量较高;层的生产力随环境条件产生相互排斥或补充各异变化;种的生产力反映了种在群落中的地位和作用,决定群落的结构特征。

The initial research results of the project "impacts of climate change on productivity of forests in China" was presented in the present paper. In view of the relationship between productivity and environment, the characteristics of geographic distribution of primary productivity of forests in China were analyzed by comparison, and the relationship between stratal productivity, environmental conditions, species productivity and community structure were explored. The results showed net primary productivity, annual litterfall decreased gradually with the increase of latitude and altitude, whereas a reverse trend occurred in the standing crop of litter, which is heavily determined by temperature and precipitation regimes; there was no significant difference in the standing crop of biomass among various forest vegetations distributing in different physiographical zones, but mature natural forests with a complicated structure and high species diversity usually possessed a relatively larger amount of biomass; stratal productivity exhibited different variations in reciprocal exclusions or complements under different environmental conditions; species productivity varied with community structure, and it represented its role and position within a community, and therefore determined traits and nature of a community.