Research On Water Requirement Of 6 Kinds Of Plants Restored In Dananhu Second Mine Of Hami,Xinjiang

As the main energy source in China,coal will cause damage to the ecological environment in mining areas when it is mined.Therefore,ecological restoration in coal mining areas is a very urgent task.In arid areas,water resources play a decisive role in vegetation restoration.High temperature,drought and water shortage are the most important ecological environmental factors that restrict the vegetation growth in the ecological restoration in arid areas.Hami region of Xinjiangis rich in coal resources,which plays a pivotal role in the development of coal resources in Xinjiang.Based on the investigation of the basic data of the water resources of the second Dananhu mine in Xinjiang and through the field observation tests in different seasons,in this paper,the water consumption law of transpiration of 6 kinds of common restoration plants in the process of ecological restoration in coal mine area was studied,The potential evapotranspiration and actual evapotranspiration of plants were calculated by using Penman formula and water balance equation.Besides,this paper also puts forward the water demand of different plants in different months in the ecological restoration of coal mine area,which provides a theoretical basis for the irrigation of different plants in the ecological restoration of coal mine area.The main conclusions are as follows:(1)The gush-out water in the mineral pit and the surface water of Yushugou reservoir is used as the water source for production of the second Dananhu mine.The average annual water consumption is 58.15×104 m3,which is mainly used for production,domestic and ecological purposes.At present,the mining area has a green area of 6.11×104 m2,and the green water is reclaimed water and tap water from the domestic sewage treatment station.The water quality of reclaimed water meets the green water standard,and the water consumption in 2019 is 12.90×104 m3.(2)The transpiration rate and net photosynthetic rate of the single leaf of six restoration plants reached the highest in July and the lowest in November between June and November.The transpiration rate of 6 plants in July was as follows:Elaeagnus angustifolia L.(1 1.67mmol/(m2·s))>Sorghum sudanense(10.45 mmol/(m2·s))>Ulmus pumila L.(9.41 mmol/(m2·s))>Salix fragilis(8.65 mmol/(m2·s))>Lycium barbarum L.(7.68 mmol/(m2·s))>Phragmites communis(5.96 mmol/(m2·s)).The diurnal variation of transpiration rate of Salix fragilis and Lycium barbarum L.was bimodal,with the phenomenon of transpiration "siestas".The remaining four plants were unimodal.The water use efficiency of six plants in the observation period was as follows:Sorghum sudanense(7.02 mmol/mol)>Lycium barbarum L.(6.50 mmol/mol)>Elaeagnus angustifolia L.(5.84 mmol/mol)>Salix fi-agilis(5.67 mmol/mol)>Phragmites communis(5.50 mmol/mol)>Ulmus pumila L.(3.42 mmol/mol).On the whole,stomatal conductance,atmospheric temperature and relative humidity are the main factors affecting transpiration rate of single leaf.(3)Based on the current planting mode of restoration plants in the ecological demonstration area of the mining area,the water demand of 6 restoration plants in 4 months is as follows:Sorghum sudanense(555.10 mm)>Lycium barbarum L.(453.08 mm)>Elaeagnus angustifolia L.(452.21 nun)>Salix fragilis(315.99 mm)>Phragmites communis(303.23 mm)>Ulmus pumila L.(270.27 mm).Plants have the largest water requirements in July,and the water requirements for Ulmus pumila L.,Elaeagnus anguustifolia L.,Salix fragilis,Lycium barbarum L,,Sorghum sudanense,and Phragmites communis in July are 87 m3/mu,210 m3/mu,99 m3/mu,147 m3/mu,183 m3/mu,100 m3/mu.Under the condition of proportion allocation of six restoration plants,the irrigable area can be 2.56×104 m2 according to the current medium amount of water in the mine.