The changes in hydrology of the Suomo River resulting from climate fluctuation and land cover changes during 1960-1990 were analyzed. During this period, Suomo basin experienced increases in annual precipitation, streamflow and floods . Annual precipitation increased with a rate of 0.45-1.71mm/a, while heavy rain events did not show significant upward trends.In the dry season temperature increased , in raining season temperature decreased. While annual mean temperature changed little .During 1957-1974, forest coverage decreased and droped to 25% in 1974. After that, it began to rise and reached 30% in 1985. The storage of forest decreased from 423m3/ha in 1957 to 177m3/ha in 1998. In the meantime, the hydrologjcal system changed obviously. Annual streamflow became increasingly great and upward trend was more significant than that of annual precipitation. In the 1970's,annual runoff increased by 6.5% than that in the 1960's. In the 1980's annual runoff increased by 15% than that in the 1960's. In the 1970's and the 1980's, precipitation was 19.4mm and 39.9mm more than that in the 1960's.While runoff increased 37.7mm in the 1970's and 87.0mm in the 1980's. According to water balance equation, evapotranspiration decreased by 10% in the 1970's and 25% in the 1980's respectively. The annual potential evaporation is 900mm in the basin,while real evapotranspiration is only about 200mm based on water balance for many years.Thus,decrease in evapotranspiration resulting from temperature change is small,the main reason for evapotranspiration decreas is that rainfall interception and soil water storage decease which is related with land cover change in the basin. Flood events became more often and serious during 1959-1999. Soil erosion increased greatly and its upward trend was most significant.
DENG Hui-ping, LI Xiu-bin, ZHANG Ming, CHEN Jun-feng, ZHANG Yi-li
. A Study of Changes in Hydrology Resulting from Climate and Land Cover Changes in the Suomo Basin[J]. SCIENTIA GEOGRAPHICA SINICA, 2001
, 21(6)
: 493
-497
.
DOI: 10.13249/j.cnki.sgs.2001.06.493
[1] David C M, Kenneth D F. Water resources planning and climate change assessment methods[J]. Climatic Change, 1997, 37(1): 25-40.
[2] Dracup J A, Kendau D R. Floods and droughts. In: Waggoner P. Climate Change and U.S. Water Resources. New York: Wiley J, 1990. 243-257.
[3] Gleick P H. Regional hydrologic consequences of increases in atmospheric CO2 and other trace gases[J]. Climatic Change, 1987, 10: 137-161.
[4] Kenneth D F, David C M. Climate change and water resources[J]. Climatic Change, 1997, 15: 423-447.
[5] Bosch J M, J D Hewlett. A review of catchment experiments to determine the effect of vegetation changes on water yield and evapotranspiration[J]. Journal of Hydrology, 1982, 55:3-23.
[6] Keppler E T, R R Ziemer. Logging effects on streamflow: Water yield and summer low flows at caspar creek in Northwestern California[J]. Water Resources Research, 1990, 26(7):1669-1679.
[7] Jones J A. Peak flow responses to clear-cutting and roads in small and large basins, western Cascades, Oregon[J]. Water Resources Research, 1996, 32(4):959-974.
[8] 刘昌明.黄土高原森林对年径流影响的初步分析[J].地理学报,1978, 33(2):112~116.
[9] 陈刚起,马学慧.三江平原沼泽开垦前后下垫面及水平衡变化研究[J].地理科学,1997, 17(增刊):427~433.
[10] 谭术魁.1998年长江中下游特大洪灾的土地利用思考[J].地理科学,1998,18(6):493~500.
[11] Stanley A C and Misganaw D.Detection of changes in streamflow and floods resulting from climate fluctuations and land use—drainage changes[J]. Climatic Change, 1996, 32: 411-421.
[12] Jens K L,Jens C R, Dominic M. Assessing the effect of land use change on catchment runoff by combined use of statistical tests and hydrological modeling:Case studies from Zimbabwe[J]. Journal of Hydrology, 1998, 205: 147-163.