Forest Hotspots in the Biodiversity Hotspot of New Caledonia

Description This dataset explores threats to New Caledonia's forests, focusing on the probability of deforestation within hotspots of tree community diversity. The probability of deforestation was derived from the "Spatial scenario of tropical deforestation and carbon emissions for the 21st century" (Vielledent et al., 2023), available as downloadable GeoTIFFs for New Caledonia for the years 2050 and 2100 Hotspots of tree community diversity were identified using the 'Core Forest' class extracted from the dataset 'Classification of New Caledonia Forests According to Edge and Elevation Effects'. Core forest are defined as forest areas located more than 300 meters from the forest edge, characterized by potentially richer tree communities. To assess habitat quality, each core forest fragment was surrounded by a 500-meter buffer zone. We evaluated forest habitat metrics including forest cover, forest type distribution, and fragmentation index within these buffer zones. Additionally, we analyzed the areas of forest threatened by deforestation in 2050 and 2100. The resulting maps provide decision-making support for stakeholders involved in conserving New Caledonia's forests. The fragmentation index used is the effective mesh size (meff), originally proposed by Jaeger (2000) and updated by Moser and al. (2007) to address boundary effects. A higher index value indicates less fragmented forest. Content This dataset was generated, analyzed, and validated using a suite of open-source software tools, including QGIS, PostgreSQL, PostGIS, Python, and the GDAL library, operating on a Linux platform. The compressed file includes six essential files formatted for an ESRI GIS system, utilizing the WGS84 international coordinate system. It is compatible for upload into spatial databases such as PostgreSQL/PostGIS. Each entry in the attribute table represents a buffer area containing one or several core forests, with the following fields (restricted to 10 characters): Field Type Description id_buffer INTEGER Unique identifier for the buffer area_ha NUMERIC (2 DECIMALS) Area of the buffer in hectares frag_index NUMERIC Forest fragmentation meff index within the buffer forest_cov NUMERIC (2 DECIMALS) Proportion of forest within the buffer area (%) edge_r NUMERIC (2 DECIMALS) Proportion of forest area classified as edge forest (%) mature_r NUMERIC (2 DECIMALS) Proportion of forest area classified as mature forest (%) core_r NUMERIC (2 DECIMALS) Proportion of forest area classified as core forest (%) defor_2050 NUMERIC (2 DECIMALS) Proportion of forest threatened by deforestation in 2050 (%) defor_2100 NUMERIC (2 DECIMALS) Proportion of forest threatened by deforestation in 2100 (%) pn BOOLEAN True or False, indicating if the polygon overlaps with the Northern province ps BOOLEAN True or False, indicating if the polygon overlaps with the Southern province Limitations This analysis of forest conservation issues aims to foster dialogue between forest ecologists and forest management strategies in New Caledonia. It should not be applied blindly based solely on the few quantitative variables proposed. Various scenarios can utilize these metrics, and we urge managers to initially define conservation objectives (such as maximizing biodiversity, reducing fragmentation, restoring disturbed environments, etc.) and consider constraints (such as accessibility, budget, feasibility, etc.) before utilizing this dataset. While threats was projected for future scenarios, conservation efforts should also prioritize preserving forests in their current state, including addressing increasing fragmentation and biodiversity loss. We encourage users to explore these metrics and their correlation with other quantitative or qualitative variables to gain a deeper understanding of conservation challenges in New Caledonia's forests.数据集描述 本数据集聚焦新喀里多尼亚森林面临的威胁，重点探讨树木群落多样性热点区域内的森林砍伐概率。 森林砍伐概率源自《21世纪热带森林砍伐与碳排放空间情景》（Vielledent等人，2023），该研究针对新喀里多尼亚发布了2050年与2100年两个年份的可下载GeoTIFF格式数据。 树木群落多样性热点区域的识别，基于从《基于边缘效应与海拔效应的新喀里多尼亚森林分类》数据集提取的"核心森林(Core Forest)"类别。核心森林指距离森林边缘300米以上的森林区域，其树木群落物种丰富度较高。 为评估生境质量，我们为每个核心森林斑块设置了500米的缓冲带。在此缓冲带范围内，我们评估了多项森林生境指标，包括森林覆盖率、森林类型分布以及破碎化指数。此外，我们还分析了2050年与2100年受森林砍伐威胁的森林面积。最终生成的地图可为参与新喀里多尼亚森林保护的利益相关方提供决策支持。本次采用的破碎化指数为有效网格大小(meff)，该指数最初由Jaeger（2000）提出，后经Moser等人（2007）修正以解决边界效应问题。指数值越高，代表森林破碎化程度越低。 数据集内容 本数据集通过一系列开源软件工具生成、分析并验证，包括QGIS、PostgreSQL、PostGIS、Python以及GDAL库，运行于Linux平台。压缩包包含6个适配ESRI地理信息系统的必备文件，采用WGS84国际坐标系，可兼容上传至PostgreSQL/PostGIS等空间数据库。 属性表中的每条记录对应一个包含一处或多处核心森林的缓冲区域，各字段（字段名限制为10个字符）如下： 字段名 类型 描述说明 id_buffer INTEGER（整数） 缓冲区唯一标识符 area_ha NUMERIC（保留2位小数） 缓冲区面积，单位为公顷 frag_index NUMERIC（数值型） 缓冲区内的森林破碎化有效网格大小(meff)指数 forest_cov NUMERIC（保留2位小数） 缓冲区范围内的森林覆盖率（%） edge_r NUMERIC（保留2位小数） 被归类为边缘林的森林面积占比（%） mature_r NUMERIC（保留2位小数） 被归类为成熟林的森林面积占比（%） core_r NUMERIC（保留2位小数） 被归类为核心林的森林面积占比（%） defor_2050 NUMERIC（保留2位小数） 2050年受森林砍伐威胁的森林面积占比（%） defor_2100 NUMERIC（保留2位小数） 2100年受森林砍伐威胁的森林面积占比（%） pn BOOLEAN（布尔型） 布尔值，用于标识该多边形是否与北部省份重叠（是/否） ps BOOLEAN（布尔型） 布尔值，用于标识该多边形是否与南部省份重叠（是/否） 局限性说明 本针对森林保护问题的分析旨在推动新喀里多尼亚森林生态学家与森林管理策略制定者之间的对话，不应仅基于本数据集提供的少量定量变量盲目套用。 该数据集的指标可适配多种情景，我们敦促管理人员在使用本数据集前，首先明确保护目标（如最大化生物多样性、降低破碎化程度、修复受干扰环境等），并综合考量各类约束条件（如可达性、预算、可行性等）。 尽管本研究针对未来情景预测了森林威胁，但保护工作也应优先保护当前状态的森林，包括应对日益加剧的森林破碎化与生物多样性丧失问题。我们鼓励用户深入探究这些指标及其与其他定量或定性变量的相关性，以更全面地理解新喀里多尼亚森林保护面临的挑战。