模擬降雨條件下人工苜蓿和檸條群落對(duì)產(chǎn)流、產(chǎn)沙的影響.pdf

1、分類(lèi)號(hào)：g15二3UDc：：!絲密級(jí)：壘匠丕蕉童堡學(xué)校代碼：10712研究生學(xué)號(hào)：SY20040378西北農(nóng)林前提夫?qū)W2007屆攻讀碩士學(xué)位研究生學(xué)位(畢業(yè))論文模擬降雨條件下人工苜蓿和檸條群落對(duì)產(chǎn)流、產(chǎn)沙的影響學(xué)科專(zhuān)業(yè)研究方向研究生指導(dǎo)教師合作指導(dǎo)教師完成時(shí)間盔堡掛生藍(lán)送絲隨造逾垣筐堡勃塑簦型國(guó)撞塹壅旦王國(guó)粱墅堡班塞員2Q壁2生魚(yú)旦中國(guó)陜西楊凌EFFECTOFARTIFICIALMeicagoSoivaANDCaraganakorsh

2、inskiiCOMMUNNITIESoNRUNOFFSEDIMENTUNDERSIMULATEDPRECIPITATIoNCoNDITIoNGSVegetationisoneofthekeymeasurementsforsoilandwaterconservationinLoessPlateauHowevertherearefewresearchesontheinfluenceofnativecommunitiesontherunoff

3、andsedimentinthisregionBasedonartificialprecipitationandlaboratorialanalysis，thechangesofRunoffsedimentyieldcharacteristicswerestudiedonslopeswitlltwonativecommunities(MeicagoSoivaandCaraganakorshinski0，andtheseconclusio

4、nscouldbedrawnasfollows：(1)EffectonRunoff：Comparedwithcontrolslope。thetimefromprecipitationtunoffemergencewasdelayedontheslopeswithMeicagoSoivaandCaraganakorshinskiiWiththeincreasingofrainintensityandinvariabilityoftheve

5、getationcoverage，thetimefromprecipitationtunoffemergencebecomeshorterInadditionwitlltheincreasingofvegetationcoverageandtheinvariabilityoftherainintensitythetimefromprecipitationtonmoffemergencebecomelonger111etimeincont

6、rolslopeis3minwhentherainintensityis128mm／minwhilethetimeis55swhentherainintensityis247mm／minWiththeincreaseofrainintensityandinvariabilityofthevegetationcoverage，therunoffyieldisincreasingsharplyOntheotherhandtherunoffy

7、ieldisdecreasingwitlltheincreaseofvegetationcoverageandtheinvariabilityoftherainintensityTherunoffyieldonslopewimCaraganakorshinMdicommunitiesisgreaterthanontheslopewimMeicagoSoivacommunity(2)Effectonsediment：Thesediment

8、yieldonslopeisdecreasingwiththeincreaseofvegetationcoverageInthebeginningstagethesedimentyieldincreasedslowlywithprocessofprecipitationInthelatterstage，howeveritincreasedsharplywithprecipitationprocessTheincreasingofsedi

9、mentyieldhassignificantdifferenceamongslopes、^，itlldifferentvegetationcoveragesThereducedsedimentyieldcouldreach70—80％whenvegetationcoverageisabove80％ComparedwithMeicagoSoivacommunitytheCaraganakorshinskiicommunitieshasb