简介：我们数学老师又漂亮又时尚。可是她在上课时却严肃得很。如图所示，只要有人一开小差，她立马变脸。

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简介：欧洲的各大媒体在愚人节这天都会各施绝招，比比谁最有想像力，谁的假新闻更“真”!

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简介：Inthisresearch,fiveNitrariasibiricaprovenancessuchasDayiluwereselectedtodoexperimentofsalt-resistance,combiningfixedplotstestwithtypicalplotinvestigation,measuringsurvivalrateandgrowthasmainindicators.TheexperimentsofmainculturaltechnologyweredoneonNitrariasibiricain4typesofsitepreparation,3typesofplanting,3designsforplantingdensity.TheNitrariasibiricaexperimentsfortheeffectsofcurbingsaltandimprovingsoilweredonebytestingsoilnutrients,saltcontent,soilphysicalpropertiesasfocalpointsintypicalsiteof3-4yearswoods.TheexperimentresultsshowedthattheNitrariasibiricacouldsurvivewellwithsoilsaltcontentof0.6%,andthatsurvivalratedeclineddistinctivelyassoilsaltcontentexceeded0.8%.However,highsoilsaltcontentdidnotinfluencegrowthintheyearofplanting.Therewereobviousdifferencesinsalt-toleranceamongNitrariasibiricaprovenances;Dayiluwasthebestonsalt-tolerance,theother4provenanceshadnodifferences,andobviouslyinferiortoDayilu.Thedifferenttypesofsitepreparationclearlyinfluencedplantingsurvivalrate,conservingrateandgrowth.Themethodoftwo-ploughing-two-harrowingwasthebestamongall4typesofsitepreparation.Seedforestationwaslargelylimited,bared-rootedseedlingforestationmaybepopularisedwhensoilsaltcontentwaslessthan1%andsoilmoisturecontentwasbetterinspring.Forestationwithcontainerseedlingwassuitedtocoastalsalinesoilinrainyseason.TheoptimumplantingdensityofNitrariasibiricawas2505/haintheYellowRiverDeltaareainviewofcoveragerate,yieldoffruitsandcostofplanting.Generallyspeaking,Nitrariasibiricacouldeffectivelyrefrainsoilfromaccumulationofsaltinthesurfacesoil,decreasesaltcontentandincreasesoilnutrient,andheightensoilcapillaryporerate.