Study On Technology And Application Of Evapotranspiration Separation Monitoring

Evapotranspiration is an important part of the hydrological cycle.Obtaining reliable and effective evapotranspiration data is an important data basis for building a complete hydrological information base.Currently,most of the existing evapotranspiration monitoring are for surfaceatmosphere or surface-atmosphere interface flux measurement.It's difficult to directly obtain the flux change process of each component.In view of the common problems existing in monitoring equipment,this paper proposes improvements to the existing Multi-cylinder compensated evaporator.The effects of the separated data on the calculation of ecological water demand,the evaluation of water resources utilization efficiency and the efficiency of the measures to reduce evapotranspiration were discussed.The main research results of this paper are as follows:(1)On the basis of existing multi-cylinder compensated evapotranspiration apparatus,the improvement measures of multi-cylinder evapotranspiration separation monitoring device are put forward in many aspects.For example,cylinder structure,measurement method and water level regulation method.It forms a set device that continuously and automatically collects the evapotranspiration of wetland plants and realizes the wireless transmission of data processing process without damaging the growth of the plant.(2)Both Zhalong Wetland and Baiyangdian Wetland used separation monitoring technology to measure the evapotranspiration of plant communities.Data show that evapotranspiration of plant communities is directly related to their growth characteristics.Both water surface evaporation and plant emission are sensitive to changes in environmental conditions.In addition,rainfall significantly inhibited water surface evaporation and plant evapotranspiration.(3)Evapotranspiration separation data is more accurate and reliable compared with the previous evapotranspiration data.It can support the in-depth study on the measures of drag reduction and evapotranspiration efficiency and its influence.And physical floating cover can effectively inhibit the evaporation of small water bodies has been proved by experiments.