The Innovation Team of Agricultural Allocation and Regional Development of the Institute of Agricultural Resources and Regional Planning (IARRP) of the Chinese Academy of Agricultural Sciences (CAAS) has achieved important progress in  mapping winter fallow arable lands in south China. The research outputs showed that the spatial distribution and duration of winter fallow lands in south China  (15 provinces and municipality), providing valuable data support for the rational development and utilization of winter fallow lands in China. The related research findings have been published in "GIScience & Remote Sensing".

Accurately mapping and obtaining the distribution of winter fallow lands and its acreage  is crucial for the reasonable utilization and development for these lands. In previous studies of winter fallow lands, the commonly used dynamic threshold method often employed universal or empirical thresholds, neglecting vegetation physiological characteristics and spatial heterogeneity. Moreover, the fragmentation of arable lands in south China and the difficulty in ignoring scale effects have limited the accuracy of large-scale extraction of winter fallow lands.

The research team collected over 3,000 sample points of winter fallow and non-winter fallow arable lands in the  study area, constructing the probability density functions of the Normalized Difference Vegetation Index (NDVI) for winter fallow and non-winter fallow lands in south China.  Team members analyzed statistically significant probability thresholds and, based on this, obtained the spatial distribution and duration of winter fallow lands at a 30-meter resolution for the period of 2021-2022. The results indicated that in south China, there are approximately 260 million Chinese mu (1 hectare =15 Chinese mu)of arable lands with winter fallow periods exceeding 100 days and about 210 million mu with winter fallow periods exceeding 120 days.

The IARRP Doctoral student Wang Xiangyi is the first author, with researcher He Yingbin as the first corresponding author. This research was supported by National Key R&D Program of China “Protection and Utilization of Black Land by Sci-tech Innovation” (2023YFD1500200), The Agricultural Science and Technology Innovation Program (ASTIP) (CAAS-ZDRW202101, G2023-18-2), Fundamental Research Funds for Central Non-profit Scientific Institution (G2023-01-27), National Natural Science Foundation of China (41771562), and Central Agricultural Office, Ministry of Agriculture and Rural Affairs (0123038).

[Citation and Original Link]:

Wang, X., He, Y., Zha, Y., Chen, H., Wang, Y., Wu, X., Ning, J., Feng, A., Han, S., Luo, S., 2024. Mapping winter fallow arable lands in southern china by using a multi-temporal overlapped area minimization threshold method. GIScience & Remote Sensing 61, 2333587. https://doi.org/10.1080/15481603.2024.2333587