| Drought and water shortage is a worldwide problem, and the water resource ofour country is especially short , one person occupy only 2200 m3, which does notreach 1/4 of the average of the word .The seriously shortage of water resources hasbecome one of the main factors that limit our country agricultural developmentcontinuously. Jiang-Huai watershed region belongs to semi-arid areas andsemi-wetness areas, locating the north subtropics. It's seasonal drought is very serious,for example ,even it is in flood year, there is also seasonal drought. Jiang-Huaiwatershed region lies in the south of the Huaihe river and the north of the YangtzeRiver . and which comes into being the shape of the "ridge of fish" .It belongings tomountain Dabie's tail ridge, and it has mostly sloping fields, thus the water flow iseasy formed on the surface of earth , and the soil's ability of keepping water isweak, And mostly parts of this region locates below irrigation water level, and theterrain is broken up, thus it not proper to establish to large-scale water conservancyfacilities, the economy and social development also can not keep up with. Accordingto above reasons, for the sake of improving agriculture productivity and agricultureproduce level, during 2004 March to 2005 May, the writer proceeded with theexperiment of run-off in the farmland of Anhui Agricultural university and theexperiment of vegetable water-saved cultivated, and draws main conclusionshereinafter: 1.With Hefei region as representative, Analyze the infiltration characteristics ofJiang-Huai watershed region ,point out the rainfall infiltration is divided into thestage of flux -control and the stage of the section -control ,the rate of infiltration inthe stage of flux-control is equal to the intensity of rainfall. 2.In the term of artificial simulation of rainfall , applying the model of SCSprinciple that is put forward by the water and soil conservation bureau of the UnitedStates, getting a the value of CN for the soil of Hefei region is enlarger along with theaggrandizement of the slope, that is to say, the runoff is enlarger along with theaggrandizement of the slope. 3. Point out if we consider to collect the rainstorm only, one farmland with thearea of 667m~2 can collect water of the runoff by 40m~3 at most. we can digwater-harvesting ditch with the capacity of 40m~3 along with contour line. The crosssection of water harvesting ditch is trapezia, with 1.5m high ,1.2m up-width,0.8down-width. Regarding my school's agricultural demonstration district as theexperiment of macrocatchment water harvesting ,it can collect rainfall by 9548.8mmannually. 4.In the different mulchings , the amount of the growth of garlic that is handledwith double film mulching is biggest, and the amount of the growth that is handledwith one film is the least, smaller control, this may because the disposal with onefilm mulching brings much weed .but the water use efficiency of garlic dealt with onefilm is as three times as the control, and that of the garlic dealt with straw mulching ishigher 60% than the control. The WUE of disposal with double film mulching is thehighest. 5.The evapotranspiration per day of corn in vegetable period without mulchingfilm is as three times as the evapotranspiration of corn with mulching film, and theamount of evapotranspiration of corn with straw is medium. The evapotranspirationper day of corn in shooting period is increasing along with the growth of the corn .Thewater consumption without mulching film is as 2.7 times as that with mulching film.From the vegetable period to shooting period , the WUE of corn with mulching film isas 4 times as that with mulching film.
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