Multiple Cropping Intensity in China Derived from Agro-meteorological Observations and MODIS Data  

作　　者：YAN Huimin XIAO Xiangming HUANG Heqing LIU Jiyuan CHEN Jingqing BAI Xuehong 

机构地区：[1]Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences [2]Department of Botany and Microbiology,Center for Spatial Analysis,University of Oklahoma

出　　处：《Chinese Geographical Science》2014年第2期205-219,共15页中国地理科学（英文版）

基　　金：Under the auspices of Strategic Priority Research Program-Climate Change:Carbon Budget and Relevant Issues of Chinese Academy of Sciences(No.XDA05050602);Major State Basic Research Development Program of China(No.2010CB950904);National Natural Science Foundation of China(No.40921140410,41071344);Land Cover and Land Use Change Program of National Aeronautics and Space Administration,USA(No.NAG5-11160,NNG05GH80G)

摘　　要：Double-and triple-cropping in a year have played a very important role in meeting the rising need for food in China.However,the intensified agricultural practices have significantly altered biogeochemical cycles and soil quality.Understanding and mapping cropping intensity in China′s agricultural systems are therefore necessary to better estimate carbon,nitrogen and water fluxes within agro-ecosystems on the national scale.In this study,we investigated the spatial pattern of crop calendar and multiple cropping rotations in China using phenological records from 394 agro-meteorological stations(AMSs)across China.The results from the analysis of in situ field observations were used to develop a new algorithm that identifies the spatial distribution of multiple cropping in China from moderate resolution imaging spectroradiometer(MODIS)time series data with a 500 m spatial resolution and an 8-day temporal resolution.According to the MODIS-derived multiple cropping distribution in 2002,the proportion of cropland cultivated with multiple crops reached 34%in China.Double-cropping accounted for approximately 94.6%and triple-cropping for 5.4%.The results demonstrat that MODIS EVI(Enhanced Vegetation Index)time series data have the capability and potential to delineate the dynamics of double-and triple-cropping practices.The resultant multiple cropping map could be used to evaluate the impacts of agricultural intensification on biogeochemical cycles.Double-and triple-cropping in a year have played a very important role in meeting the rising need for food in China. However,the intensified agricultural practices have significantly altered biogeochemical cycles and soil quality. Understanding and mapping cropping intensity in China′s agricultural systems are therefore necessary to better estimate carbon,nitrogen and water fluxes within agro-ecosystems on the national scale. In this study,we investigated the spatial pattern of crop calendar and multiple cropping rotations in China using phenological records from 394 agro-meteorological stations（AMSs） across China. The results from the analysis of in situ field observations were used to develop a new algorithm that identifies the spatial distribution of multiple cropping in China from moderate resolution imaging spectroradiometer（MODIS） time series data with a 500 m spatial resolution and an 8-day temporal resolution. According to the MODIS-derived multiple cropping distribution in 2002,the proportion of cropland cultivated with multiple crops reached 34% in China. Double-cropping accounted for approximately 94.6% and triple-cropping for 5.4%. The results demonstrat that MODIS EVI（Enhanced Vegetation Index） time series data have the capability and potential to delineate the dynamics of doubleand triple-cropping practices. The resultant multiple cropping map could be used to evaluate the impacts of agricultural intensification on biogeochemical cycles.

关 键 词：agricultural intensification multiple-cropping crop calendar agro-meteorological observation moderate resolution imaging spectroradiometer（MODIS） 

分 类 号：S163[农业科学—农业气象学] TP79[农业科学—农业基础科学]