Research On Wetland Ecological Water Requirment Based On Land Use And Land Cover Change

The Yellow River delta wetland is the most intact, widest and the youngest ecological system in the warm temperate zone of China.the ecological water requirement is the key of maintaining the wetland’s ecological functions and health, so the research of wetland ecological water requirement has great significance. The wetland ecological landscape has significant change due to climate change and the influence of human activity.This thesis mainly study on the ecological water requirement under Yellow River delta wetland land use and land cover change, analyse the water requirement that maintaining the wetland’s ecological functions and health dynamically, forecast the future ecological water requirement of the Yellow River delta wetland, the specific research contents:(1) Use remote sensing technology to analyse wetland’s land use and land cover change in years1989,1995,2004and2010, then forecast landscape and vegetation changes in the future by using first order markov chain model.(2) Take area changes of the land use and land cover as the impact factors for the ecological water requirement to separately calculate the water requirement in different levels and periods based on the wetland management objectives.The results of the study show that the ecological water demand of Yellow River delta wetland has increasing trend, the strengthening of wetland protection work contributes to that, which make the Yellow River delta wetland function recover and continuously enhance for more water.The implement of ecological restoration measures formed a virtuous cycle that water supply meets water requirement and water demands promoting the supply.(3) According to the calculation of the water requirement in the future based on wetland landscape and vegetation forecasting information, the minimum water requirement of Yellow River delta wetland in2014is13.05×108m3, moderate water requirement is18.48×108m3and the ideal water requirement is26.50×108m3.In2019the minimum, moderate and ideal water requirements are13.48×108m3,18.97×108m3and27.53X108m3. In2024the minimum, moderate and ideal water requirements are14.02×108m3,19.60×108m3and28.37×108m3. Currently water supply measures can only satisfy the requirements of the estuarine area, more popular and effective water supply measures should be taken to meet the requrirement of the other retrogradation wetland areas and to improve the fresh water resources utilization.