Environmental fragility and vegetation cover dynamics in the Lapa Grande State Park, MG, Brazil

Abstract: The environmental fragility analysis evaluates the susceptibility of an environment to degradation. Thus, the goals of this work are to analyze and map the environmental fragility of the Lapa Grande State Park (PELG), Brazil, and its buffer zone (ZA) and also quantify the changes in the vegetation cover before and after the implementation of the PELG. The environmental fragility was evaluated through multicriteria analysis using the factors: slope, geology, pedology and land use and land cover. The changes in the high vigor vegetation cover were determined from the normalized difference vegetation index (NDVI) for 1996, 2006 and 2016. It was verified that the central-east and northeast regions of the PELG presented the greatest environmental fragilities in 1996, and significant reductions in the areas with high and very high fragility were observed in 2006 and 2016 due to the increase in the vegetation cover after the implementation of the PELG, which was more expressive in the park area than in the ZA. The increase of 20.7% of 2006 to 2016 in the vegetation with greater vigor, proved the importance of the creation of a conservation unit.摘要：环境脆弱性分析旨在评估生态系统发生退化的易感性。本研究以巴西拉帕格兰德州立公园（Lapa Grande State Park，PELG）及其缓冲区（ZA）为研究对象，旨在分析并绘制其环境脆弱性分布图谱，同时量化该公园设立前后的植被覆盖变化。本研究采用多准则分析方法开展环境脆弱性评估，选取坡度、地质条件、土壤特性及土地利用与土地覆被作为评估因子。基于1996年、2006年与2016年的归一化差分植被指数（NDVI）数据，本研究确定了高活力植被覆盖的动态变化特征。研究结果显示：1996年PELG的中东部与东北部区域环境脆弱性最高；2006年与2016年，得益于PELG设立后植被覆盖的恢复提升，该区域内高、极高脆弱性等级的地块面积显著减少，且公园核心区域的植被改善效果较缓冲区更为显著。2006年至2016年间，高活力植被面积增长20.7%，这一结果充分证实了设立保护地的重要生态意义。