论文部分内容阅读
乌江流域是西南地区重要经济中心的生态和安全屏障,其上游地区长年面临水土流失和土地石漠化等问题,严重影响到当地和长江沿岸人民的生产生活。本文基于贵州省毕节地区2010年森林二类调查小班数据,运用综合能力蓄水法对乌江上游地区森林生态系统水源涵养量进行估算,分析了水源涵养能力的空间分异特征,并使用线性回归和相关分析法对森林水源涵养能力与林地海拔、坡度和土地退化类型之间的关系进行了深入探讨。结果表明:(1)2010年,研究区森林生态系统的水源涵养总量为563.05×106m3,单位面积水源涵养量达774.73 t/hm2,水源涵养能力分布表现为东部地区自东北向西南逐渐减弱、西部地区强弱相间的碎片化分布特征;(2)随着林地海拔的升高,森林单位面积水源涵养量表现出显著的下降趋势(P<0.01),海拔平均每上升1000 m,单位水源涵养量相应减少90.56 t/hm2左右;(3)森林水源涵养能力与坡度呈显著的负相关(P<0.01),坡度平均每增加1°,单位水源涵养量相应减少2.44 t/hm2;(4)土地退化对森林水源涵养功能的影响较大,退化土地的森林水源涵养能力较非退化土地平均下降23.50%。正确认识森林生态系统的水源涵养功能及其空间差异,对了解当地森林生态系统现状,以及制订实施更有针对性、更高效的水资源可持续利用和生态环境恢复及建设等相关政策具有重要意义。
The Wujiang River Basin is the ecological and safety barrier of the important economic center in Southwest China. Its upstream areas have been facing many problems such as soil erosion and rocky desertification for many years, seriously affecting the production and living of people on the coast and along the Yangtze River. Based on the small forest data of the second forest survey in 2010 in Bijie prefecture of Guizhou Province, this paper estimates the water conservation of forest ecosystems in the upper reaches of the Wujiang River using integrated water storage method and analyzes the spatial heterogeneity of water conservation capacity. Using linear regression and The correlation analysis method is used to discuss the relationship between forest water conservation ability and the elevation, slope and land degradation of forestland. The results showed as follows: (1) In 2010, the total water conservation of forest ecosystem in the study area was 563.05 × 106m3, and the water conservation capacity per unit area was 774.73 t / hm2. The water conservation capacity showed a gradual decline in east China from northeast to southwest, (2) With the elevation of forestland elevation, the water conservation per unit area of forest showed a significant decreasing trend (P <0.01), and the average elevation of each elevation was 1000 m. The unit water conservation (3) There was a significant negative correlation between forest water conservation capacity and slope (P <0.01). For every 1 ° slope increase, the unit water source conservation decreased by 2.44 t / hm2. (4) Land degradation has a great influence on the forest water conservation function, and the degraded land has an average water conservation capacity of 23.50% less than that of non-degraded land. Correct understanding of water conservation function and its spatial differences in forest ecosystems is of great significance to understand the current situation of local forest ecosystems and formulate more targeted and efficient water resources sustainable utilization and ecological restoration and construction policies .