摘要
碳、氮同位素值对监测流域植被组成、环境变迁是一种非常有效的指标,为中短时间尺度环境变化研究提供了一条新的途径。以亚热带山区的东江流域为例,以流域内的植被、土壤及水体悬浮物为研究对象,应用其有机质同位素组成(δ13C、δ15N),揭示流域植被的成分和环境变化的信息。研究发现:东江流域土壤碳同位素、C/N比值差值不大;植被的氮同位素差值明显,C/N比值差异较大。对东江流域悬浮物δ13C值近20年的监测表明:其值在早期逐年升高,近10年来转趋稳定并呈明显下降趋势,变化范围在-17.8‰~-26.1‰之间,反映了该流域植被破坏和恢复的过程以及土壤侵蚀状况的变化趋势。
Carbon and nitrogen stable isotope composition(δ 13 C,δ 15 N)are effectual indicators for monitoring vegetation and environmental change,which offer a new method to observe the environmental change in a short-medium scale.This paper analyzes δ 13 C,δ 15 N and C/N ratios in Dongjiang river basin and reveals the vegetation and environmental changes in this region.Results indicated thatδ 13 C and C/N ratios of soils were not very different,butδ 15 N and C/N ratios of vegetations had an apparent difference. Theδ 13 C of suspended sediment gradually became"partial positive"in 1990’s but"partial negative"in recent years.The carbon sta-ble isotope composition ranged from-17.8 to-26.1‰,which reflected the change trend of soil erosion,vegetation disruption and recovery in Dongjiang river basin.
出处
《生态环境学报》
CSCD
北大核心
2010年第5期1186-1190,共5页
Ecology and Environmental Sciences
基金
国家自然科学基金项目(40601092)
中国博士后科学基金项目(20060390621)
广东省科技攻关项目(2008A060204003)
关键词
东江流域
土壤
植被
悬浮物
碳、氮同位素组成
Dongjiang river basin
soil
vegetation
suspended sediment
carbon and nitrogen isotopic composition