摘要
耕地复种指数的持续稳定关乎国家粮食安全战略,实时高效地获取复种指数时空演变的详细过程信息具有重要意义。论文基于2001—2018年500 m分辨率的MODIS09A1影像数据,利用小波谱顶点的快速自动检测方法获取了全国复种指数的时空分布图,并采用Mann-Kendall检验、启发式分割算法等方法开展了全国复种指数变化形式的时空演变规律及驱动机制研究。结果表明:全国耕地复种指数稳中有升,复种指数均值从2001年的1.14上升至2018年的1.30。全国6%的耕地面积复种指数发生显著变化(约13.5万km^2),相当于一个安徽省的面积。复种指数增加面积约占变化面积的2/3,复种指数下降面积约占变化面积的1/3。其中,复种指数增加的面积主要来源于黄土高原区、甘新区的休耕转为单季以及黄淮海区单季转双季,且集中在2004—2013年。2013年至今,全国复种指数仍呈增加趋势,黄淮海区单季转双季的面积保持持续增加是重要的影响因素。复种指数下降的面积主要来源于2009—2013年长江中下游平原区的双季转单季。保持黄土高原区、甘新区的耕地有效种植面积以及黄淮区耕地的双季种植面积,适当抑制长江中下游地区耕地复种指数的下降态势,对于稳定耕地复种指数、确保粮食安全具有重要意义。
Stability of cropping intensity of the cultivated land is related to the national food security of China,and it is of great significant to obtain detailed process information of the spatiotemporal change of cropping intensity in a timely and efficient manner.Based on the MODIS09A1 data of 500 m resolution in 2001-2018,this study mapped the spatiotemporal distribution of the national cropping intensity by using the fast automatic detection method of continuous wavelet transform,and examined the spatiotemporal change of cropping intensity and driving mechanisms by Mann-Kendall nonparametric test and heuristic segmentation method.The results show that the cropland multiple cropping index in China had risen steadily,and the average value of multiple cropping index had increased from 1.14 in 2001 to 1.30 in 2018.In 6%of the country's cultivated land area(about 135000 km2,equivalent to the area of Anhui Province),multiple cropping index changed significantly.The areas with multiple cropping index increase account for about 2/3 of the total area of multiple cropping index change,and the areas with decreased multiple cropping index account for about 1/3 of the total area of multiple cropping index change.The key regions with positive change are the Loess Plateau and the Gansu-Xinjiang region(from fallow to single cropping),and the Yellow River-Huai River-Hai River region(from single cropping to double cropping),and the changes mainly took place in 2004-2013.Since 2013,the national multiple cropping index has continued to increase.An important contributing factor is the continued increase in area of double cropping(converted from single cropping),which was mainly in the Yellow River-Huai River-Hai River region.Negative change mainly took place in the middle and lower reaches of the Yangtze River Basin where double cropping was partially replaced by single cropping in 2009-2013.Maintaining effective planting area of the cultivated land in the Loess Plateau and the Gansu-Xinjiang region and double cropping planting area of
作者
李宇
邱炳文
何玉花
陈功
叶智燕
LI Yu;QIU Bingwen;HE Yuhua;CHEN Gong;YE Zhiyan(Key Laboratory of Spatial Data Mining&Information Sharing of Ministry of Education,Fuzhou University,Fuzhou 350116,China;National Engineering Research Centre of Geospatial Information Technology,Fuzhou 350116,China;The Academy of Digital China(Fujian),Fuzhou 350116,China)
出处
《地理科学进展》
CSSCI
CSCD
北大核心
2020年第11期1874-1883,共10页
Progress in Geography
基金
国家自然科学基金面上项目(41771468,41471362)
福建省重点科技项目(2020N5002,2017I0008)
福州大学科技计划项目(GD1805)。
