Method for measuring ecological water demand of degraded wetland based on water level gradients

Abstract

The invention discloses a method for measuring the ecological water demand of a degraded wetland based on water level gradients, and the method comprises the steps: collecting the raw data of a predetermined area, wherein the raw data comprises terrain data, a land use type map and meteorological data, and the meteorological data includes temperature, air pressure, wind speed and total surface radiation quantity data; setting sample sites under different water level gradients, selecting targets species, measuring vegetation data, carrying out sample survey to obtain vegetation parameters, wherein the vegetation parameters includes a vegetation height, vegetation coverage and a leaf area index; carrying out the linear interpolating of the measured vegetation parameters to obtain annual vegetation parameter data; determining a water level threshold suitable for vegetation growth under different water level gradient conditions based on vegetation parameter data and the plant; obtaining the vegetation distribution data under different water level gradient conditions based on the water level threshold and the topographic data and land use type map of the predetermined area, measuring the annual potential evapotranspiration, and obtaining the ecological water demand of the degraded wetland based on water level gradients.

Description

technical field [0001] The invention relates to the field of water conservancy, in particular to a method for measuring ecological water demand of degraded wetlands based on water level gradient. Background technique [0002] Wetland is a unique ecosystem formed by the interaction of water and land on the earth. It is the ecological landscape with the richest biodiversity in nature and one of the most important living environments for human beings. It has huge functions and values. However, due to the double impact of climate change and human activities, the area of ​​wetlands has decreased sharply and their functions have been seriously degraded. Protection of existing wetlands, restoration of degraded wetlands and rational use of wetlands have become the most effective means to exert ecological, social and economic benefits of wetlands. Estimating the water demand of degraded wetland ecological environment is an urgent problem to be solved in degraded wetland ecology and ...

AI Technical Summary

Problems solved by technology

[0005] 2. Calculation of the annual ecological water demand of flooded swamp plants: the annual ecological water demand Wp of the flooded swamp plants to be measured = ET whole year × A / 1000 = ET growth season × (1+E non-growth season / E growth Season)×A / 1000, the patent accurately records the evapotranspiration and water consumption of the flooded swamp in the wetland to be measured through a simple evaporation barrel, combined with the evaporation monitoring data of the weather station in the wetland to be measured, it can be converted into the non-growing season wintering of the northern swamp evapotranspiration consumption, but the calculation accuracy of this patent is poor, the evapotranspiration consumption obtained has a large error, and the influence of water level gradient is not considered, which is not conducive to the restoration and protection of degraded wetlands

[0007] Step 1: Obtain the rainfall value of the river basin, and use the inverse distance weight interpolation method to perform spatial interpolation on the rainfall value of the river basin, make a rainfall distribution map and a contour map, and obtain the rainfall of the river basin , that is, the total amount of water resources; Step 2: Obtain the latent heat of vaporization, maximum temperature, minimum temperature, saturated water vapor pressure, net radiation of the canopy surface, air density, soil heat flux, specific heat of air at constant pressure, canopy Layer conductance, saturated water vapor pressure, actual water vapor pressure, aerodynamic conductance, leaf area index, surface albedo and land cover, estimate the vegetation transpiration value of the river basin, step 3: estimate the soil evaporation of the river basin value, Step 4: Estimate the terrestrial evapotranspiration of the river basin, Step 5, estimate the water surface evaporation in the river basin, that is, the evapotranspiration of the river basin, so as to obtain the real-time distribution of the total evaporation of the river basin, etc. value line map; step five: estimate the water surface evaporation in the river basin, that is, the evapotranspiration of the river basin, so as to obtain the real-time distribution contour map of the total evaporation in the river basin; The model calculation method and the empirical formula method are used to calculate the water surface evaporation in the basin, but the calculation accuracy of this patent is poor, and the evapotranspiration consumption obtained has a large error, and the influence of the water level gradient is not considered, which is not conducive to the restoration and protection of degraded wetlands

Images