Demarcation of Prime Farmland Protection Areas around a Metropolis Based on High-Resolution Satellite Imagery.

Nan Xia,Manchun Li,Yi Yuan,Hao Xu,Yuefan Sun,Yajun Wang,Penghui Jiang,Liang Cheng

doi:10.1038/srep37634

Abstract

Prime farmland (PF) is defined as high-quality farmland and a prime farmland protection area (PFPA, including related roads, waters and facilities) is a region designated for the special protection of PF. However, rapid urbanization in China has led to a tremendous farmland loss and to the degradation of farmland quality. Based on remote sensing and geographic information system technology, this study developed a semiautomatic procedure for designating PFPAs using high-resolution satellite imagery (HRSI), which involved object-based image analysis, farmland composite evaluation, and spatial analysis. It was found that the HRSIs can provide elaborate land-use information, and the PFPA demarcation showed strong correlation with the farmland area and patch distance. For the benefit of spatial planning and management, different demarcation rules should be applied for suburban and exurban areas around a metropolis. Finally, the overall accuracy of HRSI classification was about 80% for the study area, and high-quality farmlands from evaluation results were selected as PFs. About 95% of the PFs were demarcated within the PFPAs. The results of this study will be useful for PFPA planning and the methods outlined could help in the automatic designation of PFPAs from the perspective of the spatial science.

Highlights

China is the most populous and largest developing country in the world
The typical land use types for the classification were displayed in Supplementary Table 2
This study proposed a method for demarcating PF protection areas (PFPAs) in an area of rapid urbanization in China using high-resolution satellite imagery (HRSI)

Summary

Introduction

China is the most populous and largest developing country in the world. To resolve the prominent contradiction between humans and land, the “Regulations on the Protection of Prime Farmland” PFPA is not a geographic entity but a virtual space of planning concept, which means the distribution of PFs in reality cannot change just after the demarcation of the PFPAs. Overall, PFs and PFPAs are the products of the policies, aiming at the mandatory protection of high-quality farmlands. After getting the PF information, GIS spatial analysis can be used to directly plan and design the PFPA29,30. This study combined remote sensing technique (land use classification), the LESA method (quality evaluation) and GIS analysis (PFPA demarcation). The primary aims were (1) to propose a set of methods to demarcate PFPAs using high-resolution satellite imagery from the perspective of spatial science, (2) to analyze the conditions of PF protection in Shanghai, and (3) to provide a spatial analysis reference for the extraction of PF and the designation of PFPAs

Methods

Results

Discussion

Conclusion