CAJ | 학술논문

利用1956-2007年径流-输沙序列,分期定量研究了长江上游近期主要干支流输沙变化及其原因,结果显示:①长江上游1994-2002年输沙量减少1.43亿t/a,人为减沙占91.2%,主要来自嘉陵江措施减沙;2003-2007年减沙4.50亿t/a,径流减沙占14.1%,前期持续的人类活动减沙占39.8%,三峡水库蓄水拦沙、金沙江措施减沙等新增人为减沙占46.2%.②金沙江1983-2000年输沙量增加0.48亿t/a,人为增沙占74.7%,主要是工程增沙;2001-2007年输沙量减小1.183亿t/a,全部为人为减沙,包括二滩等各型水库拦沙、水保减沙和下程增沙减少.③嘉陵江1985-1993年输沙减少0.827亿t/a,人为减沙占81.4%.主要人为减沙包括农村社会经济因素变化导致的土壤减蚀和水库拦沙;1994-2007年输沙量减少1.285亿t/a,其中自然径流减沙占29.6%,前期持续人类活动减沙占42.1%,宝珠寺等新增水库拦沙和水保减沙占23.4%,另有4.9%的人为减水减沙.
이용1956-2007년경류-수사서렬,분기정량연구료장강상유근기주요간지류수사변화급기원인,결과현시:①장강상유1994-2002년수사량감소1.43억t/a,인위감사점91.2%,주요래자가릉강조시감사;2003-2007년감사4.50억t/a,경류감사점14.1%,전기지속적인류활동감사점39.8%,삼협수고축수란사、금사강조시감사등신증인위감사점46.2%.②금사강1983-2000년수사량증가0.48억t/a,인위증사점74.7%,주요시공정증사;2001-2007년수사량감소1.183억t/a,전부위인위감사,포괄이탄등각형수고란사、수보감사화하정증사감소.③가릉강1985-1993년수사감소0.827억t/a,인위감사점81.4%.주요인위감사포괄농촌사회경제인소변화도치적토양감식화수고란사;1994-2007년수사량감소1.285억t/a,기중자연경류감사점29.6%,전기지속인류활동감사점42.1%,보주사등신증수고란사화수보감사점23.4%,령유4.9%적인위감수감사.
The upper Yangtze River is the main sediment source of the Yangtze River basin and its sediment yield is closely related with its ecological environment. In recent decades, as human activities intensified strongly, sediment yield in the upper Yangtze River underwent profound changes. Using annual runoff-sediment records in the period of 1956-2007, this paper made a quantitative analysis of characteristics and causes of changes in sediment discharge of main stream and tributaries of the upper Yangtze River in different periods based on double mass curves and empirical models. Our findings are: 1. The relationship between runoff and sediment load of the main stream and tributaries of the upper Yangtze River had obvious phase characteristics, which reflected the impacts of different kinds and intensities of human activities on fluvial sediment yield and transport. The sediment discharge of the upper Yangtze River in 1994-2002 reduced 143 million tons per year and the contribution from human activities accounted for 91.2%. The main decrease was from the Jialing River. The sediment load in 2003-2007 was lowered by 450 million tons per year, of which 14.1% was induced by the reduction of runoff, 39.8% by sustain-ing human activities appearing in the earlier period, and 46.2% by sediment trapping in the Three Gorges Reservoir and by the decrease of sediment load in the Jinsha River. 2. The sediment dis-charge of the Jinsha River in the period of 1983-2000 increased by 48 million tons per year, of which 74.7% was associated with human activities, mainly construction of projects. In the period of 2001-2007, the annual sediment load of the Jinsha River was reduced by 118.3 million tons per year, all due to human activities, including various types of reservoirs among which Ertan Reservoir was the biggest one, soil and water conservation practices and decrease of sediment yield from construction projects. 3. The sediment load of the Jaling River decreased by 82.7 mil-lion tons per year in 1985-1993, of which 81.4% was related to human activities, such as the changes in rural socio-economic factors and construction of reservoirs. The reduction of sediment load reached 128.5 million tons per year in the period of 1994-2007, of which the decrease of natural runoff accounted for 29.6%, the sustaining human activities appearing in the earlier period for 42.1%, the newly-built reservoirs, such as Baozhusi reservoir, and soil and water conservation project for 23.4%, and human-induced runoff reduction for 4.9%.