Study On The Climatic Changes And Runoff Characteristics In The (?)r(?)mqi River Basin, Tianshan Mountainous, China

Studying the changes of climate and runoff about the river basin which located at the arid region has an important significance in the context of global warming. Using the data of temperature, precipitation and runoff come from the nine meteorological and hydrological observation sites located at theürümqi River Basin, this paper has calculated the average temperature and the average precipitation of Urumqi river Basin. Combine with other data come from hydro-meteorological station located from head river to the downstream, this paper analyzed change of climate and the basin runoff characteristic and their relationship from angles of the whole basin, single observation sites, annual, yearly, seasonally and the impact on runoff by climate changes and human activities.Several conclusions were drawn in this paper as follows:(1) The annual average temperature and precipitation has an ascendant trend from 1959 to 2007 inürümqi River Basin. The climatic tendency rate of annual mean temperature and annual precipitation are 0.22℃/10a and 24.9 mm/10a which indicate the temperature and precipitation are obviously ascending. The annual average temperature during the middle time of the 1990s is 0.9℃warmer than that during the time from 1959 to 1990. After the 1990s, precipitation also began increased. From 1959 to 1990, the annual average precipitation is 334.1 mm, which is 75.1 mm under that of 1991 to 2007.(2) The annual average temperature in spring, autumn and winter seasons had an ascendant trend especially the winter has the most fast ascendant trend in the basin. The annual average precipitation had an ascendant trend during the four seasons but precipitation in autumn is scarce.(3) The trend of annual average temperature and precipitation is similar to that of eastern Tianshan Mountains. Temperature change rate is lower that of eastern Tianshan Mountains. But precipitation change rate is higher. The whole trends are ascendant.(4) The abrupt changes of annual average temperatures and precipitation are happened after the 1990s except that of annual average temperatures in Urumqi meteorological stations which abrupt change happened in the middle of 1980s.This phenomenon is related to that theürümqi River Basin has enter a warm periods from 1990s. Temperature and precipitation have an 11 years change scale. This phenomenon is related to the sunspot activity.(5) The runoff ofürümqi River Basin from the early 1990s mountain began to increase since 1990s. This phenomenon is related to the temperature and precipitation rise from 1990s.(6) The runoff and precipitation has a similar cycle period. It means that precipitation has a strong influence on runoff.(7) The relevance between annual runoff and precipitation is fine at the station of Ying Xiongqiao. It expressed that annual runoff is controlled by annual precipitation.(8) The influences onürümqi River Basin caused by human activities becomes more obviously. Some effective methods should be taken to protect the environment ofürümqi River Basin so that the water resources could be sustainable utilization.