黑河下游典型生态系统水分补给源及优势植物水分来源研究  

Study of the Replenishment Sources of Typical Ecosystems Water and Dominant Plant Water in the Lower Reaches of the Heihe,China

作　　者：尹力[1] 赵良菊[1,2] 阮云峰[1] 肖洪浪[1] 程国栋[2] 周茅先[1] 王芳[1] 李彩芝[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所内陆河流域生态水文重点实验室,甘肃兰州730000 [2]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,甘肃兰州730000

出　　处：《冰川冻土》2012年第6期1478-1486,共9页Journal of Glaciology and Geocryology

基　　金：国家自然科学基金项目(91025016;91125025);国家科技支撑项目(2011BAC07B05)资助

摘　　要：通过对黑河源区降水、黑河下游河岸林生态系统、人工梭梭林生态系统梭梭及戈壁红砂生态系统土壤水和浅层地下水稳定氢氧同位素组成(δD、δ18 O)的测定,对黑河下游典型生态系统土壤水和浅层地下水的补给源进行了研究.同时通过对比分析河岸林生态系统胡杨和柽柳、人工梭梭林生态系统梭梭及戈壁红砂生态系统红砂等优势植物根系水及其对应的土壤水及浅层地下水的δ18 O,对黑河下游典型荒漠植物水分来源进行了研究,并对不同潜在水源对植物水分来源的贡献率进行了计算.结果表明:河岸林生态系统和人工梭梭林生态系统的土壤水和浅层地下水来自黑河源区的降水,源区降水通过黑河河道输水补给河岸林进而形成土壤水和浅层地下水,但人工梭梭林的土壤水蒸发作用强烈.戈壁红砂生态系统由于远离黑河,土壤水不受黑河源区中上游输水的补给.就植物水分来源而言,在河岸林生态系统中,乔木胡杨主要利用40～60cm的土壤水和地下水,灌木柽柳主要利用40～80cm的土壤水;人工梭梭主要利用200cm至饱和层土壤水和地下水;戈壁红砂主要利用175～200cm的土壤水.因此,在黑河下游极端干旱区,土壤水和地下水是维持荒漠植物生存、生长及发育的主要来源.Based on stable oxygen and hydrogen isotopes（δ18O and δD） of precipitation in the upper reaches of Heihe River and soil water and shallow groundwater of the riparian forest,artificial shrubbery forest and gobi ecosystems in the lower reaches of the river,the replenishment sources of soil water and shallow groundwater of these ecosystems were studied.At the same time,by using the IsoSource software,the plant water sources of these ecosystems in the lower reaches of the river were also investigated according to δ18O values of the root water of the Populous euphratica and the Tamarix ramosissima in the riparian forest ecosystem,the Haloxylon ammodendron in the artificial shrubberies,and the Reaumuria soongorica in the Gobi ecosystem,as well as the δ18O of soil water and groundwater.The results show that soil water and shallow groundwater of the riparian forest and the artificial shrubbery forest are replenished by river water which originates from precipitation in the upper reaches.In addition,there is strong evaporation in the artificial shrubbery forest.Owing to far away from channel of river,soil water of the gobi ecosystem is not affected by river water.In the riparian forest ecosystem,the Populous euphratica takes soil water from 40 cm to 60 cm depths and the groundwater as water resources.Soil water from 40 cm to 80 cm is the main sources of the Tamarix ramosissima.The water sources of artificial Haloxylon ammodendron are come from saturated layers of soil water and shallow groundwater at the depth of 200 cm.In the gobi ecosystem,the Reaumuria soongorica mainly absorbs soil water from 175 cm to 200 cm depth.Therefore,soil water and groundwater are main water sources to maintain survival and growth of the plants in the extremely arid regions in the lower reaches of the river.

关 键 词：稳定氢氧同位素组成(δ18O、δD) 黑河下游极端干旱区 植物水分来源 

分 类 号：Q948[生物学—植物学]