Variation Of Water Resources Quantity And Its Reason Analysis In Baiyangdian Wetland

Baiyang lake is the largest lake of freshwater and shallow lake on The north China plain and it is not only an important production base of fresh products in China, but also an important hub of water storage in Haihe river networks, which bears the important tasks of delay of flood, waterlogging and irrigation and is important to maintain eco-environment of Hebei plain. Baiyangdian lake’s vitality comes from water, water is the key to its function. However, in recent years, under the dual effects of climate change and human activities, water resources of Baiyang has a great change. So this article makes a study on variation of water resources quantity and its reason analysis in Baiyangdian Wetland and the results of the study are as follows:(1) Storage capacity and the fleeding flow quantity of water resources of Baiyangdian are mainly analyzed. The analysis results show that the water resources quantity shows a significant trend of decreased and the main show is:Storage capacity and the fleeding flow quantity of water resources of Baiyangdian are gradually reduced, and especially after80s, the two sharply reduce. The inter-annual variation of storage capacity is even than before and fleeding flow quantity of water resources show a change rule—flood season-normal season-dry season and it turns to dry season after the80s.(2) By using the statistical method, Baiyangdian basin water cycle factors are analyzed and the analysis shows that characteristics of precipitation and runoff generation and convergence are change, water resource conditions deteriorate and the degree of water resources affected by human activities are increasing. Annual rainfall process analysis results:Annual precipitation is on the decline, which is mainly caused by a significant reduction in the annual rainfall days; The precipitation frequency of each classes is stable and the proportion of precipitation quantity of small precipitation intensity is declining and that of lager precipitation intensity is increasing; The longest time of Heavy rains is about5to7days and its quantity and intensity has a obvious downward trend, which shows that the precipitation potential has dropped. Precipitation of flood and non-flood season show a trend of decrease and increase, whose amplitude is respectively12%/10a and22.6%/10a, and the precipitation distribution regularity like this make inter-annual precipitation variation even than before; Annual precipitation exists16a significant cycle mainly. Annual runoff amount analysis results: Annual runoff amount is significantly reduced; Annual runoff coefficient has a mutation after the80s, which reduce27%than before; The degree of annual runoff affected by precipitation are decreasing and its affected by other factors are significantly increasing, whose average effect proportion is respectively50.38%and49.62%. The process of once flood analysis results:The degree of runoff of once flood affected by precipitation and runoff coefficient of once flood are decreasing; Lag time of flood of once flood is increasing and its peak appears in the80s, which is mainly due to the impact of human activities in watershed which makes underlying surface factors change and lead to concentration velocity decreases and the flood process becomes flat.(3) By analyzing the hydraulic engineering, agricultural, industrial, urban and rural living water, water consumption has a increasing influence on Baiyangdian basin water resources and south-to-north water transfer project will essentially and persistently improve water resources shortage of Baiyangdian wetland.In this paper, variation of water resources quantity and its reason analysis in Baiyangdianthe are analyzed systematically, comprehensively and deeply and the analysis shows that under the dual effects of climate change and human activities, water resources quantity of Baiyangdian is decreasing. This study provides the basis for water resources management and reasonable allocation of water resources.