Mapping Cropland Abandonment in Mountainous Areas Using an Annual Land-Use Trajectory Approach

Song Song

doi:10.3390/su11215951

Abstract

In recent years, with the unceasing acceleration of China’s urbanization and rapid development of the country’s economy, cropland abandonment has become an ongoing issue, especially in mountainous areas. Mapping abandoned cropland using remote sensing technology is still challenging due to the difficulties in distinguishing abandoned cropland from fallowed land. In addition, there are few credible approaches to map timing and recultivation of abandoned cropland. In this context, this research developed an annual land-use trajectory approach to map different types of abandoned cropland based on freely available Landsat and HJ-1 satellite images with a spatial resolution of 30 m. Based on this method, five types of cropland change, including one type of fallowed land and two types of abandoned land, were identified in a mountainous town of China (Zhongduo). In addition, the timing and recultivation of abandoned cropland were assessed. The accuracy of the abandonment map was assessed as high as 86.67%. It was found that the percentages of spontaneous abandoned, induced abandoned, fallowed, stable, and lost cropland in Zhongduo were 23.16%, 8.40%, 13.69%, 27.84%, and 26.91% from 2012 to 2017, respectively. The average time for spontaneously abandoned cropland was 3.45 years. Furthermore, 50.54% of the spontaneously abandoned cropland and 12.91% of induced abandoned cropland were recultivated due to fluctuating prices of agricultural products and materials, and the implemented land transfer policy.

Highlights

Cropland abandonment, an extreme manifestation of land marginalization [1], is an ongoing trend in both developed and developing countries worldwide [2], attracting great attention at a global level [2,3,4,5]
Due to rapid economic growth, urbanization and industrialization have been vigorously promoted in recent years, accelerating the transfer of the large rural labor force to urban areas [6]
The Food and Agriculture Organization (FAO) defined abandoned cropland as cropland that has not been utilized for agricultural production or other agricultural purposes for at least five years [9], while the International Symposium on Land Consolidation and Land Reserve in 2011 defined cropland abandonment as two or more years [10]

Summary

Introduction

An extreme manifestation of land marginalization [1], is an ongoing trend in both developed and developing countries worldwide [2], attracting great attention at a global level [2,3,4,5]. The Food and Agriculture Organization (FAO) defined abandoned cropland as cropland that has not been utilized for agricultural production or other agricultural purposes for at least five years [9], while the International Symposium on Land Consolidation and Land Reserve in 2011 defined cropland abandonment as two or more years [10]. In this study, the latter definition, i.e., ceased cultivation of cropland for at least two successive years, was adopted. Most fallowed land is uncultivated for one year [11,12]

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Discussion

Conclusion