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利用美国地质调查局的逐日连续流量数据计算了美国切斯比克湾地区150个小流域的34个河流流量指标,并在整个区域和划分的3个自然地理区对选择的17个指标与4种土地利用类型和不透水地表做了相关分析。结果表明,森林在降水较少的冬春两季增加流量,雨量较高的秋季减少流量,森林面积比例的增加可以削减洪峰、延长洪峰历时、稳定流量变化。农业用地比例的增加表现为稳定流量变化,延长洪峰历时,在高原地区还可以削减洪峰流量。草地比例的提高均表现为削减洪峰流量,稳定流量变化,延长洪峰历时。随着不透水地表面积增加,洪峰流量、雨季、汛期和年流量增加,流量变化加剧,洪峰历时减少,不同地理区对不透水地表的水文响应也有所不同。
Based on the daily continuous flow data of the United States Geological Survey, 34 river flow indicators of 150 small watersheds in the Chesapeake Bay area of the United States were calculated and compared with 17 selected indicators and 4 The correlation between land use types and impervious surface is analyzed. The results showed that in the winter and spring with less precipitation, the forest increased the flow rate and decreased the flow in the autumn with higher rainfall. The increase of the proportion of forest area could reduce the flood peak, prolong the peak duration and stabilize the flow rate. The increase in the proportion of agricultural land is manifested by the steady flow changes, the prolongation of the peak duration, and the reduction of peak flow in the plateau area. The improvement of the proportion of grassland all showed the reduction of peak flow, the steady flow change and the prolongation of peak duration. With the increase of impervious surface area, flood peak flow rate, rainy season, flood season and annual flow rate increase, the change of flow rate exacerbates and the flood peak lasted for a long time. The hydrological response to impervious surface in different geographical areas is also different.