Restoration and Reestablishment of the Damaged Ecosystem in the Lower Reaches of Tarim River
Cooperative Organization:Free University of Berlin, Technical University of Berlin
Project period: 2001~2004
Main results:
The international cooperation research is developed for the purpose of combining with the key project of National Natural Science Foundation of China: the Effect on Surface Ecology Arising From Shallow Groundwater Change in the Lower Reaches of Tarim River. The project combines fieldwork and monitoring data of ecological water conveying, dried-up riverway of about 320 km long, 9 groundwater monitoring sections and 18 vegetation sample plots in the lower Tarim River: (1) It is suggested that increase of water consumption in the headwaters of the Tarim River is the main factor of water flow reduction in the main stream of Tarim River: (2) Analysis of hydrological and climate variation characteristics suggested that climate change causes runoff increasing of the headstream of the Tarim River but human activities such as excess consumption of surface water bring on runoff reducing in the lower Tarim River. The findings were seperately published in Water Management Series 2003, Acta Geographica Sinica Vol. 58 No. 2, 2003 and Science in China Vol. 34 No. 11, 2004. (3) It revealed dynamic regulation of groundwater level after ecological water conveying, that is, underground level in the lower reaches of Tarim River will rise with the increasing times of water conveying. Groundwater depth rose from 9.87m to 2.66m after the fourth water conveying. Transverse impact area of groundwater level along the river channel of stream water transportation gradually expanded from 450m after first water conveyance to 1050m after the fourth water conveyance. It proposed the way of combining water conveyance with surface water conveyance to enlarge effect of water conveyance. The result is published in Science in China Vol. 34 No. 5, 2004. (4) Groundwater is the only water resource to sustain vegetation in the lower reaches of Tarim River through analysing and groundwater depth has direct relations with the composition and distribution of natural vegetation and species diversity. The result was separately published in Environmental Science 2003, Journal of Desert Research and Journal of Glaciology and Geocryology 2004. (5) It suggesteda reasonable ecological groundwater level, stress groundwater level and critical groundwater level of constructive species-poplar in the lower reaches of Tarim River after analysing the relation of groundwater level change and eco physiological characteristics of plants. The result is published in Chinese Science Bulletin 2003 Vol. 48 pp. 9 and Acta Botanica Sinica 2004 Vol. 46 No. 12. (6) On the basis of dicsussion on damaged process of ecology and effect of shallow groundwater change in the lower reaches of Tarim River, the results point out that the interaction of natural factors and human factors is the major driving force of ecological environment degradation in the lower reaches of Tarim River and evaluate water requirement for maintaining eco-security of Tarim River.
The expected goal of the project has been achieved: Nine long-term monitoring sections, 40 ground water monitoring wells and 18 vegetation sample plots have been built through the project, 80 papers have been published, senven postgraduate students graduated, and two international conferences were held. The accomplishment of the project provides important scientific basis for making ecological water conveyance plan and protection objectives in the lower reaches of Tarim River.
