简介：Thepatternofprecipitation,includingprecipitationamount,frequencyandintensity,maychangeinthefutureaccordingtothepredictionofclimatechange.Inaridzones,thesoildynamics,plantgrowthandvegetationchange,desertificationandhydrologymightbeaffectedbyprecipitationchange.Ingeneral,theprecipitationinextremearidzoneandaridzoneshowedanincreasetendencywhereastheprecipitationinsomeareainsemi-aridzoneandsub-humidaridzoneshowedadecreasetendency.Theincreaseofprecipitationcouldenhancethegrowthofbiologicalsoilcrust,improvesoilwaterstatus,promoteplantgrowth,increasevegetationcoverage,facilitatethechangefromdesertvegetationtograsslandvegetation,anditisbenefittothereversionoflanddesertification.Inaddition,theincreaseofprecipitationcouldalsoincreasetheriverrunoff,lakestorageandpromotetheoccurrenceofflood,whilethedecreaseofprecipitationhastheadverseeffect.Thesestudieswillbenefitthepredictionofthepossibleresponseofecosystemprocessestothepotentialchangeofprecipitationpatterninaridzonesinthefuture,anditisimportanttotheconservationofnaturalvegetationandthecontrolofdesertification.Morefieldexperimentsandstudiesshouldbeconductedinthefuture,includingtheeffectofincreasedprecipitationortemperature,nitrogendepositionandCO2onsoil,vegetation,desertificationandhydrologyofaridzones,soasthemorepersuasiveresultscouldbeobtainedfromtheseexperimentsandstudies.

简介：氮使用效率(NUE)在中国是很低的，差不多70%应用的氮化肥的损失在high-yielding稻田被报导。以便调查高亲密关系的铵运输或举起的分子的基础进米饭(OryzasativaL.)，我们分析了九铵的表示侧面transporters(AMT)，OsAMT1的三各个，OsAMT2和OsAMT3，根据外部N地位在象在这些表示模式的变化一样的米饭生长的二个不同N要求阶段(年轻幼苗阶段和tillering阶段)使用即时反向的抄写聚合酶链反应(RT-PCR)。结果建议九OsAMT基因在米饭植物的不同机关被表示，包括成熟的根，新根，茎，旧叶子和新叶子并且表示模式是相应蛋白质的位置在种系发生的树上特定、独立的机关。OsAMT1；1，3；2和3；3在根和射击被表示，首先旧的叶子，OsAMT1；2和1；3主要在根，和OsAMT2；1，2；2，2；3和3；1主要在射击，首先在新叶子，并且相对更在里面茎比另外的基因。在二个不同N要求阶段的表示模式是一样；在有更大的N要求的tillering阶段，然而，OsAMTs抄本层次比在有低N要求的年轻幼苗阶段的那些大。为48h的N饥饿起来调整的OsAMT1；1，1；2，3；1，3；2，3；3并且下面调整的OsAMT1；3mRNA丰富。后面的N饥饿，NH4+和NH4NO3再供给下面调整的OsAMT1；2和3；3并且起来调整的OsAMT1；3，而NO3再供给下面调整的OsAMT1；1和1；2。这些建议OsAMT的器官特定的表示模式能被N要求和外部N地位调整。

简介：Time-temperaturesuperpositionprinciple(TTSP)wasusedtoexaminedynamicviscoelasticpropertiesofChineseFir(Cunninghamialanceolata)woodatanextremelylowmoisturecontent(0.6%).Storagemodulusandlossfactordatawereobtainedatdifferentconstanttemperaturesrangingfrom25℃to150℃infrequencymultiplexingexperiments(0.1-20Hz).Allviscoelasticcurvesatothertemperatureswereshiftedalongthelog-frequencyaxistosuperimposethemonareferencetemperature(i.e.135℃inthisstudy)curve.Theextendedstoragemodulusandlossfactorisothermalmastercurveswereoverawiderangeoffrequency.TheshiftfactorsweredeterminedtobeafunctionoftemperatureandfittedintotheArrheniusequationwiththeleastsquaresmethod.TheresultsshowedthatthestoragemodulusdatawereexcellentlyfittedintotheArrheniusmodel,indicatingthevalidityofthemodeltocharacterizethedynamicstiffnessbehaviorofdrywoodintherangeof25-150℃usingtheTTSP.However,thetime-temperatureequivalencewasnotabletopredictthedampingproperties.

简介：ThisstudywasconductedintheHuoditangnaturally-regeneratedforest,whichislocatedatthecenterofthenaturalforestregionacrossthesouthern-slopeoftheQinlingMountains.Rainwaterandstreamwatersampleswerecollectedmainlyinrainyseasonsinthearea.ThesamplepHvaluesandchemicalconcentrationsweremeasured.Theresponseofstreamwaterchemistrytorainwateracidificationintheregionwasstudied.TheresultsshowedthatlongtimerainwateracidificationcouldresultinreductionofpHvalue,Ca2+andMg2+concentrationinthestreamwater.ThechangesofK+,Na+concentrationofstreamwaterwerenotcorrelatedwiththerainwateracidification.TherewasnoresponseofZn,PbandCdconcentrationofthestreamwatertorainwateracidification.Theacidifiedrainwaterdidnotresultinthereleaseoftheheavymetalsenrichedintheforestsoil.

简介：三个米饭变化，Zhonghan3，Shanyou63和Aizizhan，当在检测微分活跃甲基的材料骑车并且响应干旱应力转移相关基因表示，被使用。实验被在干旱的条件下面的微分显示器技术与10%PEG6000答案模仿了的基因薄片和mRNA执行。结果显示甲基周期能在Zhonghan3和Shanyou63的叶子被激活，但是在干旱应力下面在Aizizhan的叶子禁止了。而且，干旱应力能导致很多methyltransferase基因的表示，特别Rubisco蛋白质methylation的抄写联系了基因，它是有益的因为Rubisco蛋白质氧化和降级的预防，和干旱应力能禁止DNAmethyltransferase基因和histonemethyltransferase基因的抄写。这结果证实活跃甲基骑车并且转移相关基因涉及米饭干旱抵抗。