简介：Basedonmeteorological,hydrological,forest,andgrasslanddatacollectedbylocationobservation,remotesensing,fieldsurveysandrelevantliteratureduring1956to2009,theecologicalenvironmentchangeinnorthernslopeoftheQilianshanMountainswasanalyzedsyntheticallyusingregressionandcorrelationanalyses.Theresultsshowedthatthetemperaturehadanannualvariationrateof0.0334℃·a-1innorthernslopeoftheQilianshanMountainssince1960,andexhibitedaraisingtrend,especiallysince1987.Theannualvariationrateofannualprecipitationwas0.5702mm·a-1,indicatingthattheprecipitationtendedtoincrease.Theclimatehadchangedfromaridtohumidinthisregionsince1976.From1956to2006,theglacierareaofsixinlandriverbasin（Shiyangheriver,Heiheriver,Beidaheriver,Shuleheriver,DangheriverandHalternheriver）andDatongheriverbasininnorthernslopeofQilianshanmountainsdecreasedby17.7%.Thicknessoftheglacierreducedabout5-20m,andthesnowlineroseabout100-140m.TheGlaciericereservesininlandriverbasinofHexidecreasedby11.4%.From1972to2007,27glaciersintheeasternsectionoftheQilianshanMountainsdisappeared.From1956to2009,therunoffchangeinthenorthernslopeoftheQilianshanMountainswasdifferentindifferentregions.TherunoffwasreducedsignificantlyinShiyangheriverbasin,increasedslightlyinHeiheriverbasin,andincreasedobviouslyinShuleheriverbasin.From1958to1988,theareaofdeforestationandfarmingwasmorethan10.0millionha,andtheforestareawasreduced0.6millionha.SincetheQilianshanMountainNatureReservewasestablishedin1989,theforestwasrestoringgraduallybecauseofcontinualprotectionandcultivating,andtheforestareawasincreased9.4millionhafrom1989to2008.Duetohumaninterference,especiallyover-grazingimpact,thequalityofthewood-land,shrub-landandgrass-landinnorthernslopeoftheQilianshanMountainswereinadegradedcondition,whichre

简介：Inrecentyears,especiallyinthesummerof2002,themostseriousforestfiresoccurredintheDaxinganMountainofHeilongjiangprovinceandInnerMongolia.TherehasbeenlongtimeseriousforestfireenvironmentinsummerinDaxinganMountain.Thegrassintheforestisscorchedforlongtimedroughtandthemoisturecontentoflitterandturflayerdecreaserapidly.Theaccumulationanddrynessoffuelbuildthesummerforestfireenvironment,whicharemajorcausedbyMeteorologicalenvironment....

简介：FifteenuplandsoilscollectedfromthemajorarableareasinNOrthChinawereusedtoassesstheavailabilityofsoilsulfur(S)toplantsinapotexperiment.SoilswereextractedwithvariousreagentsandtheextractableSwasdeterminedusingturbidimetricmethodorinductivelycoupledplasmaatomicemissionspectrometry(ICP-AES),respectively.Inaddition,mineralizableorganicS,organicS,N/Sratio,sulfuravailabilityindex(SAI)andavailablesulfurcorrectionvalue(ASC)insoilswerealsodetermined.TheSamoutextractedby1.5gL^-1CaCl2wasnearlyequivalenttothatby0.25molL^-1KCl(40℃),andbothofthemwereslightlysmallerthanthatby0.01molL^-1Ca(H2PO4)2solution,asmeasuredbyturbidimetricmethodorICP-AES.TheextractableSmeasuredbyturbidimetricmethodwasconsistentlysmallerthanthatbyICP-AES.AllmethodstestedexceptthatfororganicSandN/SratioproducedsatisfactoyresultsintheregressionanalysesoftherelationshipsbetweentheamountsofSextractedandplantdrymatterweightandSuptakeinthepotexperiment,Ingeneral,0.01molL^-1Ca(H2PO4)2-extractedSdeterminedbyICP-AESorturbidimetricmethodand0.25molL^-1KCl(40℃)-extractedSdeterminedbyICP-AESappearedtobethebestindicatorsforevaluationofsoilavailableS.

简介：持续农业生产具有到食物供应安全的重要重要性。这研究试图在北方中国平原(NCP)并且随后在县规模调查庄稼收益反应到土壤质量的空间可变性导出关键土壤质量指示物。土壤样品从表面(020厘米)在2008引用geo、拿并且表面下(2040厘米)在整个Fengqiu县的132块地里的层，在NCP的中心定位了，为随后的土壤性质的分析。年度庄稼收益从土壤样品是镇定的一样的领域被获得。土壤质量与13个土壤性质基于一个模糊集合被评估，并且它的空间分布被集成geostatistical分析和地理信息系统(GIS)调查技术。土壤质量索引被分类进五个等级，并且他们的空间分布在县以内被印射。表面土壤质量比表面下的土壤高是大约一～二个等级。质量索引因为表面和表面下的土壤断然与年度庄稼收益被联系，建议两个的重要性。土壤有机物，全部的氮，可得到的P，和可得到的K贡献了50%联合重量到土壤质量索引并且以可持续性在区域作为土壤质量地位的关键指示物被识别。

简介：EcosystemdegradationoccursinparallelwithdesertificationprocessinsandyareasofNorthChina.ThevastsandyareasinNorthChinaarecharacterizedwithflexibleenvironmentsandfragileecosystemsaswellasintensivehumanactivities.DuetotheannualprecipitationgradientdecreasesfromeasttowestinNorthChina,thewholesandyregionfallsinto3mainclimaticzones:add,semi-addanddrysub-humidzones.Theecosystemsineachtypeofclimaticzonesaredifferentinclimaticconditions,humanactivities,culturaldimensions,vegetationcovers,landscapes,andcausesandprocessesofecosystemdegradation.Therefore,themosteffectiverehabilitationmeasuresofdegradedecosystemsindifferenttypesoftheclimaticzonesarealsodifferent.Forthearidsandyareas,vegetationrehabilitationofdegradedecosystemsneedstobecompletelyclosed,assistingwithartificialmeasures,suchasplantation,irrigationorothers.Forsemi-addsandyareas,theeffectivemeasuresofvegetationrehabilitationofdegradedecosystemsincludeincreasingofproportionofforestsandrangelandsandlimitationofreclamation;reducingthecarryingcapacityoflivestockonunitareaofrangelandsandgrowthoffodderplants;andplantationonthelowlandsbetweensanddunes.Forthedrysub-humidareas,themosteffectivemeasureisenclosureofdegradedecosystemscombinedwithplantation,andinsomecases,juststopusesbygrazingorreclamation.

简介：比较方法和录象带录音机被使用以防为记录二个组操作符的操作表演的学习。时间跨度是7个月，从9月到三月。在9月的操作的表演作为参考书被拿。测试调查和数据分析的结果证明掉落树的手术效率被冷天气影响，适当地减少了18.5%在里面平均。

简介：我们评估了在北伊朗在里海附近在Tavalesh区域影响大米鱼耕作的采纳的因素。我们与无限制的问题进行了调查。数据随机从184个回答者(61个采用者和123非采用者)被收集从选择村庄取样了并且分析了使用逻辑回归和多反应分析。家庭尺寸，与一个扩展代理人的接触的数字，在扩展教育活动的参予，在社会机构的会员和农场工人的存在是为大米鱼耕作系统的采纳的最重要的社会经济的因素。另外，经济问题是采用者报导的最普通的问题。象存取的缺乏那样的另外的问题捞食物拨出，鱼的损失，高质量的鱼鱼种和脱水和差的水质量的存取的缺乏对很多个农民也重要。

简介：Nitrogen(N)lossesfromammoniumbicarbonateorureaappliedtowheatandthenfollowedimmediatelybyirrigationwereinvestigated.Ammoniavolatilizationwasdeterminedbyamicrometeorologicalmethod(ammoniasampler),totalNlosswasestimatedbythe^15Nmassbalancemethod,anddenitrificationlosswasmeasuredbythediferencemethod(calculatedfromthedifferencebetweenthetotalNlossandammonialoss)andadirectmethod(measuringtheemissionof(N2+N2O)-^15N).Totalammonialossesfromammoniumbicarbonateandureain33dayswere8.7%and0.9%oftheappliednitrogen,respectively.ThecorrespondingtotalNlosseswere21.6%and29.5%,Apparentdenitrificationlosses(bythedifferencemethod)wereratherhigh,being12.9%fromammoniumbicarbonateand28.6%fromurea.However,noemissionof(N2+N2O)-^15Nwasdetectedusingthedirectmethod.

简介：polyolefin涂的脲的有效性(Meister-5和Meister-10；CU)在小麦(TriticumaestivumL.)玉米(ZeamaysL.)旋转系统在为收割季节的三连续maize-wheat-maize位于北方中国平原的溶度计阴谋被学习。一个同位素的方法被用来把CU的命运比作非涂的脲(NCU)的，并且N申请0，100，150和225kgNha−1评价被评估。结果证明CU的氮使用效率(15NUE)是比为第一庄稼的NCU的大的13.3%–21.4%。或者，当差别方法被使用时(明显的NUE)，没有重要变化在所有三个季节在处理之中被观察。尽管无机的N从1.3m层沥滤，不到1%总数被使用N，15N的未辩别出的损失(=15N作为化肥–15N使用了的15N的损失由留在0–0.2m层–15N的庄稼–15N吸收了从1.3m层沥滤)在对待CU的阴谋是24.2%–26.5%比那些低对待NCU的阴谋。在在实验的结束的CU阴谋的0–1.3m层的硝酸盐集中是53%比对待NCU的阴谋的低。因此，CU从化肥增加了庄稼N举起并且减少了应用N的未辩别出的损失，它能减少地下水污染的风险。

简介：ＣｏｎｔｏｕｒＰｌａｎｔｉｎｇ－ＡＳｏｃｉａｌＦｏｒｅｓｔｒｙＭｏｄｅｌｏｆＣｏｍｐｒｅｈｅｎｓｉｖｅＤｅｖｅｌｏｐｍｅｎｔｏｆＡｒｉｄＭｏｕｎｔａｉｎＲｅｇｉｏｎｓｉｎＮｏｒｔｈＣｈｉｎａＢｙＦｅｎｇＸｉａｏｊｕｎＩｎｔｈｅａｒｉｄ，ｍｏｕｎｔａｉ...

简介：Fieldexperimentswereconductedinamaize(ZeamaysL.)fieldofacalcareousfluvo-aquicsoilinNorthChinaPlainforstudyingthefateandammonialossofurea-Nappliedatseedlingstage,aswellastheeffectivenessofcoatedcalciumcarbide(CCC)inreducingNlossandinimprovingtheyieldefficiencyofurea.Resultsshowthat:(1)Forthesurface-broadcasttreatmentammoniavolatilization(measuredwithmicro-meteorologicaltechnique)tookplacequickly,reachedthepeak20-26hrafterapplication,andthendeclinedgradually;thecumulativeammonialossapproachedthemaximum188hrafterapplication(30%oftheNapplied),andincreasedonlyto32%284hrafterapplication;thelatteraccountedfor71%ofthetotalloss(45%ofappliedN).(2)Inthecaseofpointplacementatadepthof5-10cm,ammonialoss188hrafterapplicationwasonly12%oftheNapplied,accountingfor40%ofthetotalloss.(3)Therewasnodifferenceintotallossbetweentheapplicationdepthsof6cmand10cm,thelossofthemwas30%and29%,respectively.(4)TotallossofNappliedatlowerrate(40kgN/ha)withpointdeepplacementat6cmdepthwasfoundonly4%oftheNapplied,itroseupto30%whentherateofapplicationincreasedto80kgN/ha.(5)Thenitrificationinhibitor,CCC,seemedtoenhanceNlossofurearatherthanreduceit,anddidnotshowanybenefiteffectinimprovingtheyieldefficiencyofurea,whichispresumablyduetothehighpotentialofammoniavolatilizationinthesoilandclimaticconditionsunderinvestigation.

简介：MicrometeorologicalandmicroplotexperimentswereconductedinthefieldoffreshlyharvestedgreencaneinQueensland,Australia.ResultsshowedthathighammonialossoffertilizerNcouldoccurunderrelativelydryconditionswhenureaorcommercialproductofmixtureofureaandmuriateofpotashwereappliedtothesurfaceofsugarcanetrash.ThemoisturecontentinthetrashandthepHoffertilizerweretwoimportantfactorscontrollingtheprocessesofureahydrolysisandammoniavolatilization.MostoftheNinthesoilwastransformedtothenitratel-nitritefromafter70daysoffertilizerapplication.Nosignificantleachingwasfound.Urea-freeNfertilizershadhigherNrecoveriescomparedtourea-containingfertilizers.

简介：在农业土地支持土壤碳隐遁是可行策略之一速度观察气候变化。然而，玷污物理骚乱由加速侵蚀加重了土壤降级过程。因此，减少通过适当farming/agricultural系统的物理骚乱是的土壤的大小和紧张对农业陆地的土壤碳水池能力的管理必要。不同土地的四个地点使用类型/耕种惯例，我)到没有为止(NT)玉米(ZeamaysL.)(NTC)，ii)到为止常规(CT)玉米(CTC)，iii)pastureland(PL)，和iv)本国的森林(NF)，在北方Appalachian试验性的分水岭车站，包括水马厩聚集在土壤总数索引上估计NT耕作的影响的美国俄亥俄，吝啬的重量直径(MWD)和几何平均数被选择直径(GMD)，和土壤器官的碳和全部的氮内容。收到的NTC阴谋恐吓粪肥增加(大约15t哈1)每隔一年。CTC阴谋包含了耕作的disking和凿子和液体化肥申请(110L哈1)。结果证明水马厩聚集和MWD比为CTC在为NTC的土壤是更大的。在0-10厘米土壤层，>4.75公里尺寸部分统治了NTC并且而在不同地点之中的1)跟随了NF的趋势，为CTC多于那是46%>PL>NTC>CTC，为在CTC上的NTC更是35%-46%。NT实践提高了在CT实践上并且这样的器官的碳内容是的土壤在农田的碳隐遁的重要策略玷污。

简介：

简介：Inaspectofthescaleofworks,theThreeNorthShelterbeltProgramisuptonowthemostmagnificentprojectofforestryecologicalconstructionintheworld.Attheendof2000,the1st,2nd,and3rdperiodsofconstructioninthe1stphase(1978-2000)hadbeencompleted.Basedonfuzzycomprehensiveevaluationmethod,thepaperisabouttheresearchesonpost-evaluationinthe1stphaseaimsoftheThreeNorthShelterbeltProgram.Theconclusionobtainedisthattheaimsarepartlysuccessful.

简介：Background:Themainobjectiveofthisstudywastoexaminetheclimaticsensitivityoftheradialgrowthresponseof13easternwhitepine(PinusstrobusL.)provenancesplantedatseventestsitesthroughoutthenorthernpartofthespecies’nativedistributionineasternNorthAmerica.Methods:Thetestsites(i.e.,Wabeno,Wisconsin,USA;Manistique,Michigan,USA;PineRiver,Michigan,USA;Newaygo,Michigan,USA;TurkeyPoint,Ontario,Canada;Ganaraska,Ontario,Canada;andOrono,Maine,USA)examinedinthisstudywerepartofarange-widewhitepineprovenancetrialestablishedintheearly1960sintheeasternUnitedStatesandCanada.Principalcomponentsanalysis(PCA)wasusedtoexaminethemainmodesofvariation[first(PC1)andsecond(PC2)principalcomponentaxes]inthestandardizedradialgrowthindicesoftheprovenancesateachtestsite.TheyearscoresforPC1andPC2wereexaminedinrelationtoanarrayoftestsiteclimatevariablesusingmultipleregressionanalysistoexaminethecommonalityofgrowthresponseacrossallprovenancestotheclimateofeachtestsite.ProvenanceloadingsonPC1andPC2werecorrelatedwithgeographicparameters(i.e.,latitude,longitude,elevation)andasuiteofbiophysicalparametersassociatedwithprovenanceoriginlocation.Results:TheamountofvariationinradialgrowthexplainedbyPC1andPC2rangedfrom43.4%to89.6%.Dendroclimaticmodelsrevealedthatwhitepineradialgrowthresponsestoclimatewerecomplexanddifferedamongsites.Thekeydendroclimaticrelationshipsobservedincludedsensitivitytohightemperatureinwinterandsummer,coldtemperatureinthespringandfal(i.e.,beginningandendofthegrowingseason),summermoisturestress,potentialsensitivitytostorminduceddamageinspringandfal,andbothpositiveandnegativeeffectsofhigherwintersnowfal.Separationoftheloadingsofprovenancesonprincipalcomponentaxeswasmainlyassociatedwithtemperature-relatedbioclimaticparametersofprovenanceoriginat5ofth