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In this paper,spatial correlation of crop yield in the middle and west of Jilin province is analyzed by us-ing the method of geostatistics swmivarivogram,taking the NDVI of NOAA/AVHRR spectrum data as the regionalized vari-able,aiming to provide theory and practical basis for field sampling of crop yield estimation using remote sensing.The ratio of nugget variance and sill of semivariograms are 21.1% and9.7% in the west and middle regions in Jilin Province respectively.This shows that the crop yields are spatially correlated.The degree and range of correlation are far different in the different situations.In the west test region,the range is 49.9km and the sill is 0.00019 .In the middle test re-gion,the range is 16.5km and the sill is 0.00453.The dissimilarity in the western test region is larger than that in the middle one.The range in which the correlation existed of the former is far larger than the later.Different characteristics of spatial correlation of crop yield are decided by the environmental factors.Samples for crop yield estimation should be extracted according to the characteristic of spatial distribution of crop yield to promote the efficiency of sampling. 相似文献
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1INTRODUCTIONAstheadvancingofthestudyonhumandimensionofglobalenvironmentalchange,thechangeoflanduseisbecomingoneoftheresearchfocuses(IGBP/HDP,1993;IGBP/HDP,1995).Landusechange,combiningwithlandcoverchange,reflectstheinterdependenceofhumanandnature.Whilethestudyonlanduse/coverchangetouchesuponalotofquestion,thedrivingforceanditsdrivingmechanismaretwoofthekeyissues(IGBP/HDP,1995).Inthemeantime,theyarethenecessarybasisofdiscussingandforecastingquantitativelylanduse/coverchangebym… 相似文献
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日本作家芥川龙之介于1921年游历中国,曾途经长沙。他这样描绘1921年的长沙:"这是一座在大街上执行死刑的城市,一座霍乱和疟疾肆虐的城市,一座能听得见流水声音的城市,一座即便入夜之后石板路上仍暑气蒸腾的城市,一座连公鸡报晓声都像在威胁着我的城 相似文献
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由于岩矿体剩余磁化强度与感应磁化强度的差异导致岩矿磁异常差异及磁偏角、磁倾角的不同，根据这一特征来判别异常性质。 相似文献
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