基于长时间序列NDVI的陕西省耕地复种指数遥感监测分析

Remote sensing monitoring analysis for the multiple cropping index of the cultivated land in Shaanxi Province based on the long time-series NDVI

复种指数反映了耕地的利用强度,利用遥感方法提取耕地复种指数可为农业产业结构调整和粮食安全保障提供科学依据。采用SPOT/VGT NDVI时序数据(2001—2007年)和MOD13Q1NDVI时序数据(2001—2011年)作为遥感数据源,利用HANTS滤波和SG滤波方法分别对两种数据源进行数据重构,进而提取出陕西省10个地(市)的耕地复种指数;根据提取结果,分析各地市复种指数的变化规律,进而对比两种方法在耕地复种指数提取过程中的效果。结果表明:两种方法均能较好地反映复种指数的变化趋势;SG滤波后提取结果普遍高于HANTS滤波后提取结果;2001—2011年,延安市和榆林市复种指数增长较快,西安市复种指数出现负增长;2007年之后,铜川、宝鸡、咸阳、渭南复种指数开始出现负增长。

The multiple cropping index reflects the degree of arable land utilizing intensity at a certain period .Ex-tracting multiple cropping index by remote sensing method could provide scientific basis for agricultural industrial struc-ture adjustment and food security .We adopted the SPOT/VGT NDVI time-series data （2001-2007 ） and MOD13Q1 NDVI time-series data （2001-2011 ） for the remote sensing data sources , reconstructed the data for these two data sources by using the HANTS filter and Savitzky-Golay filter method ,and then extracted the multiple cropping indexes of 10 cities in Shaanxi Province .According to the extracted results ,analyzed the variation rule of the multiple cropping in-dex in each city ,and then compared the effects of two methods for extracting the multiple cropping indexes .The result showed that ：Both methods can be better reflected the change trend of the multiple cropping index .The extraction result of Savitzky-Golay filter was generally higher than the HANTS filter .The multiple cropping index was increased obvious quick in Yulin city and Yan’an city from 2001 to 2011 ,while the figures in Xi’an city has been shown a negative in-crease .After 2007 ,the multiple cropping indexes were begun to appear the negative increase in Tongchuan ,Baoji ,Xi-anyang and Weinan .