简介：Fuzzyassociationrules(FARs)canbepowerfulinassessingregionalsoilquality,acriticalsteppriortolandplanningandutilization;however,traditionalFARsminedfromsoilqualitydatabase,ignoringtheimportancevariabilityoftherules,canberedundantandfarfromoptimal.Inthisstudy,wedevelopedamethodapplyingdifferentweightstotraditionalFARstoimproveaccuracyofsoilqualityassessment.AftertheFARsforsoilqualityassessmentweremined,redundantruleswereeliminatedaccordingtowhethertherulesweresignificantornotinreducingthecomplexityofthesoilqualityassessmentmodelsandinimprovingthecomprehensibilityofFARs.Theglobalweights,eachrepresentingtheimportanceofaFARinsoilqualityassessment,werethenintroducedandrefinedusingagradientdescentoptimizationmethod.ThismethodwasappliedtotheassessmentofsoilresourcesconditionsinGuangdongProvince,China.Thenewapproachhadanaccuracyof87%,when15rulesweremined,ascomparedwith76%fromthetraditionalapproach.Theaccuracyincreasedto96%when32rulesweremined,incontrastto88%fromthetraditionalapproach.TheseresultsdemonstratedanimprovedcomprehensibilityofFARsandahighaccuracyoftheproposedmethod.

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：Overaperiodoftwoyears,fieldexperimentswereconductedontwosiltyloamsoilsgrownwithfoursolanaceousvegetablecropsofeggplant(var.serpentinumBailey),tomato(var.communeBailey),sweetpepper(var.grossumBailey)andchilli(var.lengumBailey),respectively.Eachexperimentincludedfourtreatmentswithfromlowtohighdoses,0～450kgha-1foreggplant,tomatoandsweetpepper,and0～270kgha-1forchilli,ofKfertilizersintheformofsulfateofpotash(SOP)appliedtogetherwithNandPfertilizers.OneCKtreatmentwithoutK,NandPfertilizersappliedandonetreatmentofKfertilizerintheformofmuriateofpotash(MOP)appliedatthehighlevel(450kgha-i)togetherwithNandPfertilizerswereincludedintheexperimentsofeggplant,inordertocomparetheeffectsofSOPandMOP.ThefruityieldsofthetestedcropsincreasedsignificantlywiththeincreasingrateofKapplication.ThecropssuppliedwithKfertilizersyieldedmorestablyastheCV%oftheiryieldsdecreasedwiththerateofKapplication.ThedrymatterandvitaminCcontentsinfruitsoftomato,sweetpepperandchilli,andthesugarcontentandthetitratableacidityleveloftomatofruitswereincreased,andtheS/Aratio(ratioofsugarcontenttotitratableacidity)oftomatofruitsweredecreasedbyKfertilization,indicatingthatKfertilizationcouldimprovethefruitqualityofthesolanaceousvegetablecrops.However,thehighrateofKfertilizermightlowerthedrymatterandvitaminCcontentsoftomatofruitsandsweetpepperfruits.SOPwasmoreeffectivethanMOPinincreasingtheyieldandqualityofeggplantfruitsatthehighfertilizationrate;therefore,thechoiceofapplyingSOPmaybebetterforhighlevelsofKfertilization.

简介：为高度产生降级的土壤的可持续性的一个重要因素是监视即时并且写实地反映不同收割系统在土壤上强加的变化的工具的使用。为了选择，在甘蔗(SaccharumofficinarumL.)玷污优秀指示物变量在管理辨别完成敏感的标准到管理惯例和在季节之间一致性的生产区域，十件合成土壤样品(010厘米)在器官的甘蔗(OS)的耕作下面从区域在2006年3月(旱季)在2005年7月(雨季)并且再被收集，绿甘蔗(GS)，烧的甘蔗(BS)并且从一个邻近的本国的森林(NF)在UsinaTriunfo的区域，BocadaMata，Alagoas，巴西。微生物引起的biomass-C(MBC)，全部的器官的C(TOC)，表示为水解作用，水马厩土壤总数(MWD)的吝啬的重量直径，和水马厩宏的百分比聚集的荧光黄diacetate(食物及药品管理局)(PWSA)的率的土壤酶活动被分析。尽管MBC和TOC比在栽培区域在NF是更高的，没有差别在在三个甘蔗系统之间的这些C水池被观察。到地点管理的食物及药品管理局的反应依赖于采样时间。在多雨的时期，这项活动跟随了顺序：NF>OS>GS>BS在旱季，仅仅NF不同于另外的处理。不管采样时间，MWD和PWSA在顺序NF减少了>OS=GS>BS。变量MWD和PWSA为不管怎样在地点管理历史之间区别是相当敏感的采样季节。

简介：TaihuLakeregionisoneofthemostindustrializedareasinChina,andthesurfacewaterisprogressivelysusceptibletoanthropogenicpollution.Thephysicochemicalparametersofsurfacewaterqualityweredeterminedat20samplingsitesinTaihuLakeregion,Chinainspring,summer,autumn,andwinterseasonsof2005-2006toassesstheeffectofhumanactivitiesonthesurfacewaterquality.Principalcomponentanalysis(PCA)andclusteranalysis(CA)wereusedtoidentifycharacteristicsofthewaterqualityinthestudiedwaterbodies.PCAextractedthefirstthreeprincipalcomponents(PCs),explaining80.84%ofthetotalvarianceoftherawdata.Especially,PC1(38.91%)wasassociatedwithNH4-N,totalN,solublereactivephosphorus,andtotalP.PC2(22.70%)wascharacterizedbyNO3-Nandtemperature.PC3(19.23%)wasmainlyassociatedwithpHanddissolvedorganiccarbon.CAshowedthatstreamswereinfluencedbyurbanresidentialsubsistenceandlivestockfarmingcontributedsignificantlytoPC1throughouttheyear.ThestreamsinfluencedbyfarmlandrunoffcontributedmosttoPC2inspringandwintercomparedwithotherstreams.PC3wasaffectedmainlybyaquicultureinspring,ruralresidentialsubsistenceinsummer,andlivestockfarminginfallandwinterseasons.FurtheranalysesshowedthatfarmlandscontributedsignificantlytonitrogenpollutionofTaihuLake,whileurbanresidentialsubsistenceandlivestockfarmingalsopollutedwaterqualityofTaihuLakeinrainyseason.TheresultswouldbehelpfulfortheauthoritiestotakesoundactionsforaneffectivemanagementofwaterqualityinTaihuLakeregion.

简介：Afieldexperimentwasconductedfrom1999to2002tocompareandevaluatetheeffectsofnutrientandwaterregimesonpaddysoilqualitybyinvestigatingsoilchemicalandmicrobiologicalparameters.Fournutrientregimes,acontrol,chemicalfertilizersonly(CF),chemicalfertilizerswithswinemanure(SM),andchemicalfertilizerswithwheatstraw(WS),andtwosoilmoistureregimes,continuouswaterlogging(CWL)andalternatewettinganddrying(AWD),wereinvestigated.WithSMandWStotalorganiccarbonandtotalnitrogeninthepaddysoilweresignificantlyhigher(P＜0.05)thanthosewithCF.AsimilareffectfororganicamendmentswasobservedinthesoillightfractionorganicC(LFOC),water-solublecarbohydrates(WSC),andwater-solubleorganicC(WSOC).CWL,inparticularwhenswinemanurewasincorporatedintothepaddysoil,markedlydecreasedsoilredoxpotential(Eh)andincreasedtotalactivereducingsubstances(ARS).Meanwhile,ascomparedtoCF,SMandWSsignificantly(P＜0.05)increasedsoilmicrobialbiomassC(MBC)andmineralizablecarbon,withdifferencesinAWDbeinghigherthanCWL.Inaddition,SMandWStreatmentssignificantly(P＜0.05)improvedriceabove-groundbiomassandgrainyield,withAWDbeinggreaterthanCWL.Thus,forecologicallysustainableagriculturalmanagementofpaddysoils,long-termwaterloggingshouldbeavoidedwhenorganicmanurewasincorporatedintopaddysoil.

简介：Assessmentofsoilqualityisimportantforoptimumproductionandnaturalresourcesconservation.AgriculturalandpasturesoilqualitiesofDeh-SorkhregionlocatedatsouthofMashhad,northeasternIranwereassessedusingtheintegratedqualityindex(IQI)andNemeroqualityindex(NQI)modelsincombinationwithtwodatasets,i.e.,totaldataset(TDS)andminimumdataset(MDS).Inthisstudy6soilpropertiesconsideredasMDSwereselectedoutof18propertiesasTDSusingprinciplecomponentanalysis.Soilsamplesweredividedinto3groupsbasedonoptimumrangesof8soilphysicalqualityindicators.Soilsampleswiththemostindicatorsatoptimumrangewereselectedasgroup1andthesampleshavingfewerindicatorsatoptimumrangewerelocatedingroups2and3.Optimumrangesofsoilporesizedistributionfunctionswerealsodeterminedassoilphysicalqualityindicesbasedon8soilphysicalqualityindicators.Poresizedistributioncurvesofgroup1wereconsideredastheoptimumporesizefunctions.Theresultsshowedthatrelativelyhighorganiccarboncontentscouldimproveporesizedistribution.Meancomparisonsofsoilphysicalqualityindicatorsdemonstratedthatmeanweightdiameterofwetaggregates,structuralstabilityindex,theslopeofmoistureretentioncurveatinflectionpoint,andplantavailablewatercontentinagriculturallandusedecreasedsignificantlyinrelationtopasturelanduse.Inaddition,theresultsdemonstratedthatthestudiedMDScouldbeasuitablerepresentativeofTDS.78%ofpasturesoilshadtheoptimumporesizedistributionfunctions,whilethisparameterforagriculturalsoilswasonly13%.Ingeneral,thesoilsofthestudiedregionshowedhighlimitationsforplantgrowthaccordingtothestudiedindicators.

简介：Wetlandsoilqualitydegradationcausedbylarge-scaleagriculturalreclamationontheSanjiangPlainofNortheastChinahasbeenwidelyreported.Arelativesoilqualityevaluation(RSQE)modelandaprojectionpursuitevaluation(PPE)modelbasedonreal-codedacceleratinggeneticalgorithmwereintroducedtoevaluatequalityvariationsintoplayersofthemainwetlandsoilsontheSanjiangPlainin1999and2003,respectively.Assoilqualitydegradationboundarieswerevague,thisstudyestablishedtwofuzzysyntheticevaluation(FSE)modelsbasedontheoriginaldataandcriteriausedintheRSQEandPPEmodels.TheoutputsofthetwoFSEmodelswereobtainedbychoosingtwofuzzycompositeoperatorsM(∧,∨)andM(·,⊕).StatisticalanalysisshowedthattheresultsoftheFSE,RSQE,andPPEmodelswerecorrelated.Inparticular,outputsoftheFSEmodelusingM(·,⊕)weresignificantlycorrelatedwiththoseoftheRSQEmodelwithr=0.989atP<0.01.ComparedwithRSQEandPPEmodels,theFSEmodelmaybemoreobjectiveinshowingsoilqualityvariationsandwasclosertothenaturalsituation,showingthefeasibilityandapplicabilityoftheFSEmodelinevaluatingsoilqualitydegradation.However,thechoiceofcompositeoperatorwasofcriticalimportance.ThestudyofwetlandsoilqualitydegradationontheSanjiangPlainwasofscientificandpracticalsignificanceforprotectionandmanagementofsoilsandforsustainabledevelopmentofagricultureinthisareainthefuture.

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.