Soil and Water Conservation Supervision for Agricultural and Forestry Development and Other Production and Construction Activities: A Case Study of Wannian County, Jiangxi Province

[Objective] Taking Wannian County in Jiangxi Province as a representative case, this study presents the analysis results of the pilot projects on soil and water conservation supervision for agricultural and forestry development and other production and construction activities in five counties (or cities) across four provinces in the middle reaches of the Yangtze River. This study aims to assess the current status of these activities and their soil and water conservation supervision, explore regulatory technologies and methods, and invesstigate effective institutional mechanisms for supervision. [Methods] We employed 3S technology, automated image recognition technology, computer technology, database technology, wireless networks, and mobile terminals, together with field verification, surveys, and spatial analysis. Key technologies included the automatic extraction of remote sensing information, enabling fast, automatic, and accurate identification of disturbance patches and soil erosion problem patches. Based on GIS spatial analysis and processing functions, approved production and construction projects were automatically excluded, and relevant information of agricultural and forestry development was automatically integrated. Additionally, a regulatory app was developed. [Results] (1) The disturbance patches of production and construction activities exhibited high accuracy. Through field verification of 910 patches with an area ≥ 1 hm2, only 28 patches with a total area of 108.89 hm2 were identified as actual production and construction projects. The automatic extraction accuracy for disturbance patches and total area reached 96.92% and 98.41%, respectively. (2) The disturbance caused by agricultural and forestry development was significant. In 2023, a total of 1 048 disturbance patches were extracted in Wannian County, with a total area of 6 924.60 hm2, accounting for 6.07% of the county’s land area. The density of disturbance patches reached 0.92/km2. (3) The scale of disturbance was generally large. The average area of disturbance patches was 6.61 hm2, among which 910 patches were over 1 hm2, with a total area as high as 6 859.12 hm2. (4) Regarding spatial distribution, agricultural and forestry development and other production and construction activities in 2023 were distributed across the entire Wannian County, generally showing a uniform distribution pattern, with slightly more disturbance patches in the east than in the west. (5) In terms of types, the main activities included economic forest projects, land consolidation projects, farmland improvement projects, and land requisition-compensation balance projects. (6) An analysis of investment entities revealed that over 93% were projects or subsidized programs under governmental forestry, natural resources, rural and agriculture, and related departments. (7) Approximately 78% of the production and construction activities had not implemented effective soil and water conservation measures, posing significant soil erosion risks. Furthermore, soil and water conservation supervision was largely absent in practice. [Conclusions] Given the high intensity of agricultural and forestry development activities, limited implementation of conservation measures, and high risks of severe soil erosion, it is essential to strengthen soil and water conservation supervision for these activities, particularly for government-funded projects. Regulatory measures for soil and water conservation in such activities should be developed, supervision systems and mechanisms featuring “industry-based regulation and coordinated soil and water conservation” should be established, and categorized supervision should be implemented.