Study On The Influence Of Poyang Lake Water Conservancy Hub Project On Lake Surface

In order to study the influence of the proposed Poyang Lake water conservancy hub project on the water surface of Poyang Lake.Using the build of the Poyang Lake two-dimensional hydrodynamic model,in accordance with the planning of Poyang lake water conservancy hub project scheduling scheme,through scene simulation of typical flow years about high,normal,and low,respectively from the lake's wet period and dry period to choose the Poyang Lake high,normal,and low flow years,in the absence of hub and the hub have two scenarios simulation,quantitative analysis of the hub project's different water level scheduling stage's possible effect of the lake's flooded frequency,water level and water surface area and key lakes' changes about flooded frequency and water level in the high,normal,and low flow years.The results showed that:(1)afte the Poyang Lake water conservancy hub project establishment that no flooded frequency rises places are perennial with water.Lake there is rising flooded frequency mostly shallow lake and meadow.Flooded frequency increase in dry period overall is greater than in wet period,and the magnitude of the flooded frequency increase from large to small was low flow year,normal flow year and high flow year whether in wet or dry period.Water area of flooding frequency increased by more than 0 in wet period were slightly larger than dry period.(2)in wet period,the hub project has the largest rising effect on low flow year water level,followed by normal flow year,minimal impact in high flow year.In dry period,there has slight tendency that the magnitude of the water level rise from large to small was low flow year,normal flow year,and high flow year under the hub project,but the uplift effect are not large,also just swings between 0-1(m).The scope of water level rise above 0m in wet period is greater than dry period in the whole.water lifting amplitude in low flow year is the biggest whether in wet or dry period in generally,water lifting effect obvious area mainly concentrated in river channel,Tang Yin nearby water,flow from five rivers entering Poyang Lake,and meadow.No water uplift area mainly in some small lakes and meadow.The maximum range of no water level rise in the high flow year of hub project storage period.(3)the water conservancy hub project has extremely similar effect in two natural reserve core areas about water level,that is the maximum water level rise in the low flow year of wet period,and there is almost no water level rise in normal flow year and low flow year of dry period.But also slightly different,water lifting amplitude in wet period at the core area of Poyang Lake Natural Reserve is greater than the same period of the Poyang Lake Nan Ji Wetland Natural Reserve core area under the hub project,in the dry period is the opposite.The two natural reserve core areas' range of water level rise above 0m and water lifting amplitude in the wet period of the whole is greater than the dry period.(4)under the action of hub project,change tendency in Poyang Lake area and it's daily average water level is broadly in line,lake area lifting amplitude under hub project in the wet period is greater than in dry period as a whole.and the biggest water surface area lifting amplitude is in the low flow year of wet period.(5)For the difference between the flooded frequency under hub project and the natural flooded frequency in Poyang Lake,the correlation in the dry period is higher than that in the wet period,and minimal correlation is in high flow year whether in wet or dry period.The difference in the east-west direction of the whole is inverted "U" shape distribution,and in the north-south direction,there are three types of increasing / decreasing and "U" shape distribution from north to south.For the difference between the water level under hub project and the natural water level,the water with strong spatial correlation is mainly concentrated in the "northwest-southeast" on a line.The difference in the east-west direction,the whole is inverted "U" shape distribution,and in the north-south direction,main show "U" shape distribution or descending trend from north to south.