Extraction And Analysis Of Cultivated Land Based On Remote Sensing And Gis

The food that mankind depends on comes from cultivated land,therefore,farmland security is an important foundation for national food security,it is also an important guarantee for the prosperity of the country.Accurate acquisition of cultivated land information plays an important supporting role in research content such as the utilization efficiency of cultivated land and the temporal and spatial distribution of cultivated land.This article uses Sentinel-2 and GF-1 remote sensing images as the data source,take three representative townships in Zitong County as the research area,the object-oriented method is used to extract the cultivated land,which provides data support for analyzing the temporal and spatial distribution of cultivated land in the study area.The main research content and results of this article are as follows:(1)Two kinds of satellite images of different towns,according to the spectral characteristics,texture characteristics,NDVI and geometric characteristics of various ground features,establish farmlandinformation extraction model,realize the extraction of cultivated land in the study area.(2)The confusion matrix and Kappa coefficient were used to evaluate the accuracy of the cultivated land extraction results.The results show,under Sentinel-2 and GF-1 remote sensing images,the precision of cultivated land extraction and the value of Kappa coefficient in river valleys,hills,and mountains decrease in order,moreover,the extraction effect of cultivated land under GF-1 remote sensing image in each township is better than that of Sentinel-2 remote sensing image.Under the Sentinel-2 remote sensing image,the Kappa coefficients of the cultivated land extraction results are all above 0.61,explains that Sentinel-2 remote sensing images can meet the needs of subsequent research in this article.(3)According to the four phases of arable land data obtained,analyzed the status of cultivated land use in April and July 2019 and its distribution characteristics on different slope zones and elevation zones;the distribution of cultivated land from 2017 to 2021,its dynamic changes during the year,and its distribution characteristics on different slope zones and elevation zones are analyzed.The percentages of the cultivated land area of Changqing Township in April and July 2019 to the total cultivated land area were 93.37% and 98.96% respectively,the area planted in July has increased by 5.59% compared to April,mainly appear on the elevation zone ?,?,? and the slope zone ?,?,?,?.2021 compared to 2017,The area of arable land in 2021 will increase by 2hm2 compared to 2017,mainly appear on elevation zone ?,? and slope zone ?,?.The percentages of the cultivated land area of Maming Township in April and July 2019 to the total cultivated land area were 99.08% and 99.58% respectively,the area planted in July has increased by 0.5% compared to April,mainly appear on elevation zone ?,? and slope zone ?,?.2021 compared to 2017,the area of arable land in 2021 increased by 3.19 hm2 compared to 2017,mainly appear on elevation zone ?,? and slope zone ?.In Shuangban Township in April and July 2019,the percentages of the cultivated land area of crops to the total cultivated area were 99.45% and 99.84% respectively,the area planted in July increased by 0.39% compared to April.mainly appear on the elevation zone ?,? and the slope zone ?,?.2021 compared to 2017,the area of arable land in 2021 will increase by 11.31 hm2 compared to 2017,mainly appear on elevation zone ? and slope zone ?,?.(4)Pass the research,remote sensing technology can be used to monitor the cultivation of arable land,provide services for improving the cultivation of cultivated land.