Rape And The Same Phenological Crops Area Extraction Based On Multi-Source Remote Sensing Data In Jiangsu Province

The method of obtaining crop growing acreage mainly by a large area field measurements or by the statistics department escalation, this way of method not only consume manpower, material and financial resources, but cannot get the information of the spatial distribution of crops as well, nor does the realize of actual needs. Development of remote sensing (RS) technology for crop growing acreage monitoring provides a new statistical way to monitor a wide range of crop information quickly and efficiently. Agricultural Remote Sensing application has been widely used in China, in the new stage of agricultural remote sensing monitoring development, remote sensing technology could be applied to agricultural resource survey, remote sensing monitoring and estimate the actual seeding acreage, growing and production of crops, agricultural disaster monitoring, agricultural environmental protection, digital agriculture and other aspects, which will promote agricultural scientific decision-making to a new level, and meanwhile provide high quality services for agricultural production.In this article, the study area Jiangsu Province, located in the eastern coast of China’s, is China’s major agricultural province, occupies an important position in China’s grain production, especially in a leading position in rape production all over the country, made a significant contribution to food security in our country as a guarantee. With respect to some provinces, the agricultural planting structure of Jiangsu Province is special, there are two kinds of winter crops including winter oilseed rape and winter wheat. The study of oilseed rape and winter wheat planting conditions based on Remote Sensing technology in Jiangsu Province is not only good for fast food yield estimation, strengthen rape production management, but also good for guiding timely adjustment of agricultural planting structure.This study selected the lower spatial resolution of MODIS image data as main source, in addition, get vector boundary data sample area of crops through field sampling surveys, crop growing acreage image data is extracted on MODIS remote sensing image data and sample area basis. Selection of high resolution in the result by extracting the HJ-1A/B image to validate the extracted spatial distribution, HJ-1A/B image has the advantage of both high spatial and temporal resolution, choosing the image that from rape flowering that rape and winter wheat NDVI difference larger determine the spatial distribution of rape and winter wheat. The accuracy of the crop calculation area is based on the extraction area of crop.In the study of rape acreage extraction, remote sensing extraction are summarized in the previous crop acreage research and extraction problems in large-scale extraction of crop acreage, the more research using supervised classification and unsupervised classification method to extract the area, in the study, the extraction method is different from supervised classification and unsupervised classification. Research on the utilization of MODIS-NDVI data and rape field sampling survey data acquisition of rape pixel MODIS-NDVI timing diagram, drawing the curve chart that entire growing season NDVI value of rape change over time, the curve applied to the entire study area, Using MODIS-NDVI timing diagram of the study area subtract each pixel of canola’s standard NDVI timing diagram, and then calculated the average value and the absolute value of each pixel in the image, eventually, acquired an average absolute deviation map. The average absolute deviation graph contains all the rape pixels, the mean absolute deviation chart setting an appropriate threshold excluding the pixels that are not rape pixels, finally get the spatial distribution of rape pixels, further calculations rape acreage. Winter wheat and rape with same phenology period, it also is the main crop grown in Jiangsu Province, two kinds of crop phenology and spectroscopy are very close, in the extraction process can’t be ignored in the study, the distinction between the two crops are important and difficult point, winter wheat acreage extraction methods and rape extraction methods are similar, and ultimately achieve higher accuracy.In this article, rape acreage and winter wheat information are extracted base on a high temporal resolution of MODIS imagery, the results show a high temporal resolution remote sensing data have a great advantage in crop acreage monitoring, it can be used to extract rape and other crop acreage with higher precision. With the development of remote sensing technology applied in agricultural monitoring, the future would be better to continue in-depth study of remote sensing methods to extract acreage on the cultivation of crop.