摘要
非木质残体是高山森林溪流生态系统的基本组成部分,其分解过程释放的重金属元素通过长期的迁移与沉积等途径汇集到下游水体,从而成为森林生态系统元素输出的主要形式和影响流域水环境安全的潜在因素之一.于2013年8月调查了岷江上游高山森林溪流非木质残体镉(Cd)和铅(Pb)的贮量及其随溪流特征的变化.结果显示:岷江上游高山森林溪流非木质残体在单位面积集水区的Cd贮量为0.863 mg/hm2,单位面积溪流的Cd贮量为0.249 mg/m2;单位面积集水区的Pb贮量为9.19 mg/hm2,单位面积溪流的Pb贮量为2.65 mg/m2;岷江上游高山森林溪流非木质残体Cd和Pb总贮量分布较均匀,与溪流的长度、面积和流量的相关性均不显著,但会影响各组分Cd和Pb贮量及其所占比例.可见,高山森林溪流非木质残体输出是Cd和Pb等重金属元素的重要输出过程,这可为进一步研究高山森林—河岸—溪流连续体的重金属元素分配与迁移提供重要的基础数据和新的思路.
Non-woody debris is one of the primary components in forest headwater stream ecosystem. Released Cd and Pb from the non-woody debris is not only an important element output from forest ecosystems, but also an influencing factor for downstream water environment and watersheds safety. This study chose a representative alpine forest in the upper reaches of Minjiang River to investigate Cd and Pb storage of non-woody debris in the headwater streams in the rainy season of August, 2013. We studied the Cd and Pb storages and their changes along with the stream characteristics. The results showed Cd storages of non-woody debris as 0.863 mg/hm2 and 0.249 mg/m2 per unit area for catchment and streams respectively in the headwater streams of the upper reaches of Minjiang River; Pb storages of non-woody debris were 9.19 mg/hm^2 and 2.65 mg/m^2 per unit area of catchment and streams, respectively. The Cd and Pb total storage of non-woody debris was found not significantly related to the stream area, length or water flow flux. However, the stream area, length and water flux could affect the storage and proportion of Cd and Pb in leaf, bark and other non-woody debris component. The results suggested that the non-woody debris in the headwater streams stores great amount of Cd and Pb, therefore is an important component of heavy metal output in the alpine forests. The study here can provide a new idea and data in understanding heavy metal resource/sink patterns and the ecological linkage among forest-riparian-stream.
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2015年第3期528-532,共5页
Chinese Journal of Applied and Environmental Biology
基金
国家自然科学基金项目(31270498
31170423)
国家"十二五"科技支撑计划(2011BAC09B05)
中国博士后科学基金特别资助项目(2012T50782)
四川省青年基金(2012JQ0008
2012JQ0059)资助~~
关键词
水源涵养地
森林溪流
植物残体
重金属
water conservation land
forest stream
plant debris
heavy metals
