| Research article |
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| Mapping fruit orchard species for smallholders in drought-vulnerable agroforestry systems of China |
ZHANG Jingge1, HUANG Huaguo1,2, YUAN Xiaotian3, TAN Shen1,2,*( ) |
1 State Key Laboratory to Efficient Production of Forest Resources, College of Forestry, Beijing Forestry University, Beijing 100083, China 2 Engineering Research Center of Carbon Sequestration of Forest and Grassland, Ministry of Education, Beijing 100083, China 3 College of Urban and Environmental Science, Northwest University, Xi'an 710127, China |
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Abstract Fruit trees are typically organized at the orchard level, where the tree-based ecosystem is characterized by high homogeneity, leading to clustered distributions with distinct boundaries. While remote sensing-based classification techniques are well established, most studies have not treated fruit orchards as a distinct category. Whether remote sensing can effectively address orchard classification and distribution remains uncertain. This study focused on the Guanzhong Plain on the southern part of the Loess Plateau as a representative drought-vulnerable region in China, characterized by mixed orchard-cropland landscapes. Sentinel-2 imagery was used as the primary classification feature, supplemented by topographic characteristics. A Random Forest classifier was trained and validated using 1980 ground samples across major planting regions in May 2024. The final classification results were satisfactory, with an overall accuracy of 0.86. Meanwhile, a comparison against statistical data demonstrated the reasonableness of fruit orchard area: the correlation coefficients for three major fruit types (apple, grape, and kiwi) are greater than 0.75. Compared with existing land cover products, which often misclassify fruit trees as cropland or forestland, our results demonstrated that combining band reflectance time series, vegetation index time series, and topographic features can effectively differentiate fruit orchards from spectrally similar cropland and forestland. This study facilitates precise fruit orchard mapping, supporting targeted production management and ecological carbon sequestration estimation in similar regions with drought-vulnerable agroforestry systems.
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Received: 06 June 2025
Published: 31 May 2026
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Corresponding Authors:
*TAN Shen (E-mail: tanshen@bjfu.edu.cn)
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| About author: Author contributions
Conceptualization: TAN Shen, YUAN Xiaotian; Methodology: ZHANG Jingge, TAN Shen; Formal analysis: ZHANG Jingge; Writing - original draft preparation: ZHANG Jingge, TAN Shen; Writing - review and editing: ZHANG Jingge, HUANG Huaguo, TAN Shen; Funding acquisition: HUANG Huaguo, YUAN Xiaotian; Resources: YUAN Xiaotian; Supervision: HUANG Huaguo, TAN Shen. All authors approved the manuscript.
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