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简介：拿Yucheng，在是的山东省的一个典型的农业县一个盒子，应用逻辑回归建模空间地识别影响农田的因素的这研究变化。用在2001和2009的高分辨率形象的二个阶段，学习在20012009获得了陆地使用和农田变化数据。农田被5.14%在时期减少，这被发现，主要由于到森林土地的农田变换并且布满建筑物土地，尽管森林土地的部分和闲置的土地被变换成农田。逻辑回归的结果显示那个地点，人口生长和农民收入是影响农田变换的主要因素，当土壤打字时并且支持弯曲是控制农田变化的分发的主要自然因素。地区性的差别和农田变化的时间空间的变量影响了逻辑回归模型的恰当的能力。巨鸟恰当的测试显示逻辑回归模型给了地区性的陆地使用变化的好解释。逻辑回归分析是一个好工具鉴别影响陆地使用的主要因素由确定改变每个因素的贡献。

简介：TheNorthChinaPlain(NCP)isthemostimportantfoodgrainproducingareainChinaandhassufferedfromseriouswatershortages.Tocapturevariationwateravailability,itisnecessarytohaveananalysisofchangingtrendsinprecipitation.Thisstudy,basedondailyprecipitationdatafrom47representativestationsinNCPrecordspassedthehomogeneitytest,analyzedthetrendandamplitudeofvariationinmonthly,seasonalandannualprecipitation,annualmaximumcontinuousno-raindays,annualraindays,rainfallintensity,andrainfallextremesfrom1960to2007,usingtheMannKendall(M-K)testandSen’sslopeestimator.Itwasfoundthatmonthlyprecipitationinwinterhadasignificantincreasingtrendinmostparts,whilemonthlyprecipitationinJulytoSeptembershowedadecreasingtrendinsomepartsofNCP.Nosignificantchangingtrendwasfoundfortheannual,dryandwetseasonprecipitationandrainfallextremesinthemajorityofNCP.Asignificantdecreasingtrendwasdetectedforthemaximumno-raindurationandannualraindaysinthemajorpartofNCP.ItwasconcludedthatthechangingtrendofprecipitationinNCPhadanapparentseasonalandregionalpattern,i.e.,precipitationshowedanobviousincreasingtrendinwinter,butadecreasingtrendintherainyseason(JulytoSeptember),andthechangingtrendwasmoreapparentinthenorthernpartthaninthesouthernandmiddleparts.Thisimpliesthatwithglobalwarming,seasonalvariationofprecipitationinNCPtendstodeclinewithanincreasingofprecipitationinwinterseason,andadecreasinginrainyseason,particularlyinthesub-humidnorthernpart.

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简介：ＴｈｅｓｕｐｐｏｒｔｉｎｇｃａｐａｂｉｌｉｔｙｏｆｗａｔｅｒａｎｄｌａｎｄｒｅｓｏｕｒｃｅｓｆｏｒｓｕｓｔａｉｎａｂｌｅｉｎｃｒｅａｓｅｏｆｙｉｅｌｄｉｎＮｏｒｔｈＣｈｉｎａＰｌａｉｎＺＨＡＮＧＨｏｎｇｙｅＩｎｓｔｉｔｕｔｅｏｆＧｅｏｇｒａｐｈｙ，...

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简介：Thispaperproposesamethodonanalyzingtheasynchronism-synchronismofprecipitationofdifferenthydrologicalregionsregardingtheS-to-NwatertransferareasofeasternChina.Thegeneralprocessoftheanalysisincludesthreesteps.Firstly,wecreatedtherainfallseriesoftheregionconcernedbycalculatingtheregionalaveragerainfallofthestationsintheareawiththehelpoftheclassicalThiessenPolygonmethod.Secondly,thestandardsofassessmentindicesforwetnessordrynessaresetaccordingtoGammadistributionfunctionwithacertainprobabilityP37.5%or62.5%givenrespectively.Finally,thefrequencyofninecombinationsarecountedasthequantitativefeatureofasynchronismandsynchronisminthreetimescales,thatistheyearly,seasonalandmonthlyscales.Theasynchronism-synchronismoftworegionpairshasbeenestimated.Theresultsshowthatthefrequencyofprecipitationasynchronismin1957-1998islargerthanthesynchronismfrequencyforboththeNorthChina-middleandlowerYangtzeRiverpairandfortheNorthChina-upperHanjiangRiverpair.Asforthesynchronismphenomena,thefrequencyofNd-Sdisratherlow.AsthecombinationsthataresuitableforwatertransfersareNd-Sw,Nn-Sw,Nd-SnandNn-Sn,thetotalfrequencyofthesecombinationsforNorthChina-middleandlowerYangtzeRiveris40%onanannualbasis,butonly28%inspringwhenwatershortagesaremostlikelytooccur.ThetotalfrequencyofthesecombinationsforNorthChina-upperHanjiangRiverisabout24%onanannualbasis,but35%inspringandwinter.Itshouldbenotedthatiffutureprecipitationpatternsaresimilartothatoftheperiod1957-1998,itisveryimportanttochangethenaturalcharacterofasynchronism-synchronismbyenhancingthecapabilityofhydro-projectsregulationandimprovingmanagementofthewatertransferproject.

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