简介：Amodelforsimulatingcadmiumtransportinasoil-plantsystemwasbuiltusingacommercialsimulatingprogramnamedPowersimonthebasisofinput-outputprocesseshappeninginthesoil-plantsystem.COnvectiveanddispersivetransportprocessesofcadmiuminsoilprofileareembedded.Simulationsonadailybasehavebeendoneuptoatotalsimulatingtimeof250years,Resultsshowthatapplicationsofsewagesludgeandfertilizeratthesimulatedrateswouldonlycauseslightcadmiumaccumulationsineachlayerofthesoil,andcadmiumaccumulationwouldbelevellingoff,reachinganequilibriumconcentrationslayerbylayerdownwardaftercertaintime.Thetimescaletoreachanequilibriumconcentrationvariesfrom10yearsforthetopthreelayerstoover250yearsforthebottomlayers.Plantcadmiumuptakewouldincreasefrom52umm^-2underinitialsoilcadmiumconcentrationsto65ugm^-2underequilibriumsoilcadmiumconcentrations,whichwouldnotexceedthemaximumallowablecadmiumconcentrationinwheatgrains.Mainparameterswhichinfluencecadmiumaccumulationandtransportinsoilaretotalcadmiuminput,rainfall,evaporation,plantuptakeandsoilproperties.

简介：Methaneoxidationbypaddysoilsinaclosedsystemcouldbesimulatedbytheequationx=k1xo/(k1+k2x0)exp(k2t)-k2x0wherex0andxaretheCH4concentrationsattimezeroandt,respectively;k1andk2areconstantsrelatedtotheconstantoffirst-order-kinetics.AccordingtotheequationthechangeofsoilabilitytooxidizeCH4couldbeestimatedbytheequationAc=k2/k1(x0-x)x0k2/k1-1.TheresultsshowedthatthesoilabilitytooxidizeCH4varied,dependingontheinitialCH4concentration.HighinitialCH4concentrationstimulatedsoilabilitytoconsumeCH4,whilelowconcentrationdepressedtheablility.Thischaracteristicofpaddysoilseemedtobeofconsiderablesignificancetoself-adjustingCH4emissionfromfloodedricefieldsifthereexistoxicmicrositesinthesoil.

简介：Amini-plotfieldexperimentwasconductedonaloamyclayOxisoltocompareandevaluatePabsorptionandtransferinplantorgansandPmovementinsoilprofileatthreePapplicationdepthsunderthesoybean-citrusintercroppingversusthemonocultureusinga32Ptracertechnique.TotalPabsorption(Pt)bysoybeanandPaccumulation(Pa)insoybeanorgansdecreasedsignificantly(P<0.05)undertheintercroppingincontrasttothemonoculture.Withintercropping,when32Pwasappliedintopsoil(15cmsoillayer),total32Pabsorption(32Pt)insoybeanswassignificantlylower(P<0.05),butwhen32Pwasappliedtodeepersoillayers(35or55cmsoillayer),32Ptinsoybeanswassignificantlygreater(P<0.05).ThepercentageofPinleavestototalP(Pa/Pt)and32Pinleavestototal32P(32Pa/32Pt)forsoybeanwere(?)25%andthoseofroot(?)12%.WhenPwasappliedintopsoiland55cmsoillayer,nosignificantdifferenceswerefoundbetweenintercroppingandmonocultureforPtofcitrus.ThePabsorbedbycitruswastransferredrapidlytothegrowingorgansofabovegroundduringtheexperiment,andthespeedoftransferringtothegrowingorgansslowedwhenPwasappliedtothedeepersoillayers.Inintercropping,Pmobilitywasheightenedinthesoilprofile,andPindeepersoillayersmoveduptotopsoilmorerapidly.

简介：化肥氮(N)的高率在东南的中国在温室蔬菜地里被使用最大化生产；然而，如此的集中的蔬菜生产的N预算尚待被探索。这研究的目标是以五N(脲)应用程序率(0，348，522，696，和870kgNha1year1)在西红柿，黄瓜，和芹菜的年度旋转的一个温室蔬菜系统决定年度N平衡和损失。到050厘米土壤层的全部的N输入从531～1053kgha1，并且N化肥是主要N来源，为全部的年度N输入的66%83%的财务。在比较，总共的灌溉水，湿免职，和种子占了不到1%全部的N输入。化肥N使用效率仅仅在870kgNha1的常规申请率下面是18%并且当申请率从522～870kgNha1增加了，减少了。明显的N损失是196201kgNha1，71%86%被以522870kgNha1的申请率沥滤失去。因此，沥滤是以高N申请率的主要N损失小径，N的数量沥滤与在黄瓜季节期间使用的N成正比。而且，溶解器官的N说明了10%沥滤的N，而NH3挥发仅仅在五N下面贡献了明显的N损失的0.1%0.6%，申请在这个温室蔬菜系统评价。

简介：RedsoilisaveryimportantsoilresourceinsouthernChina.However,duetobeingsimultaneouslyofhighproductivepotentialitiesandseverelydegraded,itneedsharnessingurgently.RedSoilResourceInformationSystem(RSRIS)basedonremoltesensingandgeographicinformationsystem(GIS)playsanimportantroleinsurvey,evaluation,utilziationandmanagementofredsoilresource.RSRISofQuzhouCity,ZhejiangProvince(1:250000)andRSRISofLongyouCounty,ZhejiangProvince(1:50000)havebeenmaderespectivelyonSUNSPARCstationandusingRC/INFO.Thispaperintroducesthesystemdesign,databsecreationandsystemfunctions,anditparticularlyfocusesondevelopingappliedmodels,suchasredsoilresourcedivisonandmapping,suitabilityevaluation,erosionriskevaluation,plantutilizationzoneetc.TheproblemsonstudyofRSRISanditsdevelopingstrategyarealsodiscussed.

简介：Changesofsoilorganicnitrogenformsandsoilnitrogensupplyundercontinuousricecroppingsystemwereinvestigatedinalong-termfertilizationexperimentinJinhua,ZhejiangProvince,China.ThefertilizertreatmentsincludedcombinationofP-K,N-K,N-P,andN-P-Kaswellasthecontrol.Aftersixyearsofcontinuousdouble-ricecropping,totalsoilNandhydrolysableNcontentsremainedstableinplotswithNtreatments,whilethehydrolysableNcontentsweresubstantiallyreducedinthoseplotswithoutNapplication.Comparedtotheunbalancedfertilizationtreatments,PandKincreasedthepercentageofhydrolysableammoniumNinthetotalsoilNwiththebalancedapplicationofN,andalsomaintainedhigherricegrainyieldsandnitrogenuptake.GrainyieldwaspositivelycorrelatedwithtotalNuptake(r=0.875**),hydrolysableN(r=0.608**),hydrolysableammoniumN(r=0.560**)andthehydrolysableunknownN(r=0.417**).TotalNuptakewaspositivelycorrelatedwithhydrolysableN(r=0.608**),hydrolysableammoniumN(r=0.440**)andhydrolysableunknownN(r=0.431**).Soilnutrientdepletionand/orunbalancedfertilizationtoricecropreducedNcontentinsoilmicrobialbiomass,andthereforeincreasedC/Nratio,suggestinganegativeeffectonthetotalmicrobialbiomassinthesoil.

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：印射土壤硝酸盐氮(NO3-N)的空间分发是重要的指导氮申请以及估计沥滤进地下水的NO3-N的环境风险。我们采用了univariate和混合geostatistical方法在东北佛罗里达越过一处风景印射土壤NO3-N的空间分发。土壤样品从四深度增长被收集(030，3060，60120和120180厘米)基于土壤，土地使用和举起阶层从用成层的随机识别并且嵌套采样的147个采样地点设计。在二层是的顶的土壤NO3-N分布空间地，汽车相关并且印射使用木头正常kriging。为NO3-N预言的环境关联模型用线性、非线性的回归方法被导出，并且采用了开发NO3-N趋势地图。陆地使用和它从卫星形象导出的相关变量作为重要变量被识别用环境关联模型预言NO3-N。当木头正常kriging生产了顺利变化的地图时，从环境关联模型导出的趋势地图产生了空间地异构的地图。趋势地图与趋势模型剩余的平常的kriging预言被相结合开发回归kriging预言地图，它给了最好的NO3-N预言。因为土地使用和遥远地察觉到的数据是容易地可得到的并且有大部分，与地相比的更好的空间分辨率取样了土壤，我们的调查结果基于为风景的使用和遥远地察觉到的数据放大土壤NO3-N印射的土地建议了环境关联模型的功效。实现的方法论为在另外的风景土壤NO3-N印射是可转让的。

简介：Integrationofsoilinformationsystem(SIS)andinteractiveself-organizingdata(ISODATA)wasstudiedtoestablishproperagriculturaldevelopingzonesinredsoilregionofsouthernChinawhichareofcrucialimportancetofarmers,researchers,anddecisionmaderswhileutilizingandmanagingredsoilresources.SIScreatedbyusingARC/INFOwasusedtoprovidedataacquisition,systematicmodelparameterassignment,andvisualdisplayofanalyticresults.Topography,temperature,soilcomponent(e.g.,organicmatterandpH)andconditionofagriculturalproductionwereselectedasparametersofISODATAmodel.TakingLongyouCounty,ZhejiangProvinceasthecasestudyarea,theeffectoftheintegrationandrecommendationsarediscussedforfutureresearch.

简介：Thelowremovaleffciencyoftotalnitrogen(TN)isoneofthemaindisadvantagesoftraditionalsinglestagesubsurfaceinfiltrationsystem,whichcombinesananaerobictankandasoilfilterfield.Inthisstudy,afull-scale,two-stageanaerobictankandsoiltrenchsystemwasdesignedandoperatedtoevaluatethefeasibilityandperformancesintreatingsewagefromaschoolcampusforoveraone-yearmonitoringperiod.Therawsewagewaspreparedandfedintothefirstanaerobictankandsecondtankby60%and40%,respectively.Thisnovelprocesscoulddecreasechemicaloxygendemandwiththedichromatemethodby89%-96%,suspendedsolidsby91%-97%,andtotalphosphorusby91%-97%.Thedenitrificationwassatisfactoryinthesecondstagesoiltrench,sotheremovalsofTNaswellasammonianitrogen(NH+4-N)reached68%-75%and96%-99%,respectively.ItappearedthattheremovaleffciencyofTNinthistwo-stageanaerobictankandsoiltrenchsystemwasmoreeffectivethanthatinthesinglestagesoilinfiltrationsystem.Theeffuentmetthedischargestandardforthesewagetreatmentplant(GB18918-2002)ofChina.

简介：Soilqualityassessmenthasbeensuggestedasaneffectivetoolforevaluatingsustainabilityofsoilandcropmanagementpractices.Theobjectiveofthisstudywastodevelopasensitivesoilqualityindex(SQI)basedonbulkdensity(BD),water-holdingcapacity(WHC),water-stableaggregates(WSA),aggregatemeanweightdiameter(AMWD),totalorganicC(TOC)andCinputtoevaluatetheimportantrice-wheatcroppingsystemonanInceptisolinIndia.Along-termexperimenthasbeenconductedfor18yearsattheIndianCouncilofAgriculturalResearch-IndianInstituteofFarmingSystemsResearch,Modipuram,India.Thetreatmentsselectedforthisstudywerecomprisedofano-fertilizercontrolandN,PandKfertilizers(NPK)combinedwithZnandSfertilizers(NPK+Zn+S),farmyardmanure(NPK+FYM),greengramresidues(NPK+GR)andcerealresidues(NPK+CR),laidoutinarandomizedcompleteblockdesignwiththreereplications.SoilsampleswerecollectedandanalyzedforBD,WHC,WSAandTOC.Correlationanalysisrevealedthatbothriceandwheatyieldssigni?cantlyincreasedwiththeincreasesinAMWD,TOCandCinput,butdecreasedwiththeincreaseinBD.TheSQIvalueswerethengeneratedbasedonregressionanalysisofBD,WSA,AMWD,TOCandCinputwithriceandwheatyieldsforthe0–15and15–30cmsoillayers,respectively.RegressionanalysesbetweencropyieldsandSQIvaluesshowedaquadratictypeofrelationwiththecoeffcientofdetermination(R~2)varyingfrom0.78to0.89.Withregardtosoilsustainability,applyingcropresiduestobothriceandwheatcouldmaintainsoilqualityforalongerperiod,whereasthehighestyieldsofboththecropswererecordedintheNPK+Zn+Streatment.Theregressionequationsdevelopedinthisstudycouldbeusedtomonitorsoilqualityinasubhumidtropicalrice-wheatcroppingsystem.

简介：PhysiographyandsoilinMaeRimwatershed,ChiangMaiProvince,Thailandwereinvestigatedbyusingaerialphotographsandsatelliteimageinconjunctionwithfieldwork,andsoilinfiltrationrateandsoilshearresistanceweremeasuredinfield.ManyfactorsaffectingrunoffwereanalyzedusigtheIntegratedLandandWaterInformaitonSystem(ILWIS).Asaresult,amodeldeterminingfloodhazarwassetup.Threempsincludingrunoffcurvenumbermap,runoffcoefficentmap,andfloodinumdationmapwerecreated,Inaddition,thetimeofconcentrationwaspredicted.

简介：土壤性质空间变异是一种普遍现象，但等高绿篱——坡地农业复合系统中土壤性质空间变异的研究较少。本文以设置在三峡库区王家桥小流域的香根草（Vetiveriazizanioides）绿篱试验小区为研究对象，从径流小区尺度探讨了不同措施对土壤性质空间变异的影响。结果表明，绿篱种植可降低O．2～0．002mm粒级团聚体的空间变异，绿篱＋有机肥与绿篱＋无机肥措施可降低〈0．002mm粒级团聚体的空间变异，绿篱＋覆盖措施能降低0．2—0．002mm粒级团聚体的空间变异。绿篱种植可降低土壤有机碳、全氮、全磷、速效磷养分空间变异。施肥措施对系统内土壤养分空间变异影响不同，绿篱＋有机肥措施增大了全磷、速效磷的空间变异，绿篱＋无机肥措施增大了速效钾的空间变异。

简介：水文自动测报系统能够对雨量、水位等水文信息进行自动采集、处理与实时传递，能有效解决江河湖泊及水库的洪水预报、防洪调度和水资源合理利用，改变了人工测量的落后状况，并扩大了测报范围，增长防洪决策的预见期，效益明显，因而被越来越多的防汛部门所采用。本文简单介绍了自动测报系统在亚湖水库的配置及运行情况。

简介：为揭示煤炭开采对山西森林生态系统的影响，为矿区植被恢复提供基础资料，以山西省大规模煤炭开采区、采空区和受煤炭开采影响表征比较明显的区域为调查范围，地带性的油松次生林为主要调查林分，结合以往的调查统计数据和遥感资料，与非开采区特征相近的森林生态系统对比分析。结果表明：全省因煤矿开采破坏林地133．68km^2；采煤区林地土壤的Hg、Cd含量是山西土壤平均含量的3．26倍和2．73倍；采煤区林地阴、阳坡土壤含水量比非采煤区分别降低18．0％和23．4％；采煤区油松的生物量和生产力比非采煤区平均下降15．08％和15．30％；采煤区油松群落的物种丰富度、多样性、水土保持和水源涵养功均呈下降态势。

简介：农村生活污水是农村面源污染的重要来源。通过为期1年的农村污水水质监测，研究松花坝水源区建立池塘系统对农村污水的净化效果。结果表明：1）池塘系统对铵氮、总氮、总磷的输出具有较好的控制效果，最高去除速率分别为3．78、4．20、1．06g／（m^2·d），最大去除率分别为88．35％、79．28％、86．49％；2）由于硝化和反硝化作用同时存在，硝态氮的含量变化不能准确地反映池塘对硝态氮的去除效果；3）池塘系统对污染物的去除效果与污染物的输入速率呈负相关关系。研究结果可为松华坝水源区农村面源污染治理提供一定的理论依据。

简介：选取盐化草甸、柽柳和河岸林胡杨林作为塔河流域自然生态系统的表征,分析不同干旱年份,塔河干流来水量对地下水位的影响,以及地下水位变化过程中自然生态系统的生态响应,并对塔河干流段不同干旱年份河岸生态系统进行情景分析。结果显示:塔河流域干旱程度直接影响其地表生态特征,干旱程度的加剧,导致径流量的减少,从而引发河岸地下水埋深的增大,进而引起流域植被生态特征的变化。随着地下水埋深的增加,盐化草甸、柽柳和河岸林胡杨林均出现水分胁迫的状况,地下水埋深3.5m为草甸植被生长胁迫深度,地下水埋深5m为柽柳生长的胁迫深度,地下水位埋深4.5m为胡杨生长的胁迫深度。通过对塔河干流段不同干旱年份生态情景分析可以看出,在保证率分别为75%,90%和95%的干旱年,距离河道100m处,地下水埋深在4~4.28m范围内,盐化草甸植被开始受影响,柽柳和胡杨长势良好,当地下水埋深大于4.28m,草甸植被受影响较大;距离河道300~1000m的距离,地下水位埋深在4.19~5.71m的范围内,草甸植被消失,柽柳、胡杨生长开始受到影响;距离河道1500m处,地下水埋深在5.71~5.98m的范围内,柽柳、胡杨生长停滞,濒临死亡,当地下水埋深达到6.06m,柽柳和胡杨出现枯死的现象。

简介：小流域生态系统服务功能分为产品提供功能、调节功能、文化功能和支持系统功能。小流域生态系统的产品提供功能包括提供农业产品（包括种植业产品、牧业产品和渔业产品）、提供原材料和提供淡水资源；小流域生态系统的调节功能包括涵养水源、固定CO2、释放O2、净化环境、净化水源和洪水控制；小流域生态系统文化功能包括旅游价值、文化和科研价值；小流域生态系统的支持功能包括土壤保持、营养物质循环和提供生物环境价值。该文系统阐述上述小流域生态系统各项服务功能与价值的估算方法，对于小流域生态系统服务功能与价值评估具有一定的参考价值。

简介：以华北土石山区51块油松（Pinustabulaeformis）林标准地为研究对象,运用主成分分析法选取主成分指标,运用聚类分析法对标准地进行分类,通过构造综合评价指数对其生态系统健康状况进行评价。结果表明：所选样本可分别被判定为Ⅰ级优质健康、Ⅱ级良好健康、Ⅲ级一般健康、Ⅳ级亚健康和Ⅴ级不健康5级,Ⅰ级优质健康的油松林标准地共有6块,其中5块为很少有人为干扰的天然林,1块为人工林,其他健康级别全部为人工油松林,依次为12块1、1块、18块和4块;评价方法能够比较客观地反应所调查油松林的健康状况,具有一定的科学性和可操作性,可达到定量化评估华北土石山区油松林生态系统健康的目的,对该区森林生态系统健康经营具有一定的参考价值。

简介：本文以福建省明溪县农业科技园区管理信息系统为例，开展基于“GIS”的农业科技园区管理信息系统建设研究，介绍了管理信息系统中的数据处理、项目库管理、图件管理、文档库管理等主要功能模块，对基于“GIS”农业科技园区管理信息系统的构建进行探讨。