Regional epidemic laws of poplar Ice Nucleation Active bacterial can-ker

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摘要 Throughthemethodsofcorrelationanalysisandmainfactoranalysis,therelationshipbetweenthepoplarINAbacterialcankerandcircumstanceswasanalyzedand9mainfactorsforaffectingthediseasewereselected.Basedonthecomprehensiveanalysisofmainfactorsandinducedfactors,thestandardforriskgradesofthisdiseasewaspromotedandnortheastregionofChinawasdividedinto4districtswithdifferentriskgrades:seriouslyoccurringdistrict,commonlyoccurringdistrict,occasionallyoccurringdistrict,andun-occurringdistrict.NonlinearregressionanalysisforsixmodelcurvesshowedthattheRichardgrowthmodelwassuitablefordescribingthetemporaldynamicsofpoplarINAbacterialcanker.Bystepwisevariableselectionmethod,themulti-variablelinearregressionforecastingequationwassetuptopredictthenextyear'sdiseaseindex,andtheGM(1,1)modelwasalsosetupbygreymethodtosubmitmiddleorlongperiodforecast.
机构地区 不详
出处 《林业研究:英文版》 2001年3期
出版日期 2001年03月13日(中国期刊网平台首次上网日期,不代表论文的发表时间)