The coordination of development efforts and ecological conservation in China's border regions is a significant challenge due to the overlap of biodiversity hotspots, ecologically fragile zones, and impoverished areas. Achieving the harmonious integration of ecological preservation and economic development relies on the fundamental assessment of ecological security (ES). However, comprehensive assessments of ES in border regions remain limited. This study introduces a new index, the multivariate ecological security index (MESI), which integrates ecosystem vigor, organization, elasticity, services and risk. Here, the MESI was utilized to assess the temporal and spatial changes in ES and its associated impact factors in the China-Myanmar border region (CMBR) from 2000 to 2020. The MESI provides a clear representation of the actual ES status in the CMBR, exhibiting a significant correlation with the eco-environmental quality index (EEQI; p < 0.01). The ES status exhibited notable spatial heterogeneity in the CMBR, consisting primarily of both relatively safe and safe levels, which accounted for approximately 85% of the total area. From 2000 to 2020, the CMBR experienced a gradual improvement in ES status, with the area experiencing an increase in the ES level accounting for 23.41% of the total area, which exceeded the proportion of the area experiencing a decrease in the ES level (4.71%). The combined impact of multiple factors exerted a greater influence on ES than did individual factors alone. Notably, human factors increasingly influenced the ES status during the study period. The results of this study provide valuable insights for ecological preservation and sustainable management in the CMBR, and the MESI can be extended to assess the ES of other regions.

Previous research has primarily focused on soil erosion issues in arid and semi-arid regions, with a limited understanding of soil erosion mechanisms in tropical areas. Additionally, there is a lack of a holistic perspective to determine the spatial attribution of soil erosion. The conversion of tropical rainforests into economically driven plantations, like rubber and pulpwood, has resulted in distinct soil erosion characteristics in specific regions. To enhance our knowledge of soil erosion patterns and mechanisms in tropical regions, it is necessary to examine soil erosion in the three major watersheds of Hainan Island from 1991 to 2021, which encompass significant geographical features such as tropical island water sources and tropical rainforest national parks. The study employed the China Soil Loss Equation (CSLE) model, slope trend analysis, Pearson correlation analysis, land-use transfer matrix, and spatial attribution analysis to examine soil erosion under different scenarios. The research results indicate that scenarios driven by the combination of natural and human factors have the greatest impact on soil erosion changes in the entire study area. Co-driven increases affected 53.56% of the area, while co-driven decreases affected 21.74%. The 31-year soil erosion showed an overall increasing trend. Human factors were identified as the primary drivers of increased soil erosion in the Nandu River basin, while a combination of climate and anthropogenic factors influenced the decrease in soil erosion. In the Changhua River basin, climate and human activities contributed to the soil erosion increase, while human activities primarily caused the decrease in soil erosion. In the Wanquan River basin, climate intensified soil erosion, whereas human activities mitigated it. This study underscores the significant combined impact of human activities and natural factors on soil erosion in tropical regions. It emphasizes the importance of considering human-induced factors when implementing soil erosion control measures in tropical regions.

The damage caused by soil erosion to global ecosystems is undeniable. However, traditional research methods often do not consider the unique soil characteristics specific to China and rainfall intensity variability in different periods on vegetation, and relatively few research efforts have addressed the attribution analysis of soil erosion changes in tropical islands. Therefore, this study applied a modification of the Chinese Soil Loss Equation (CSLE) to evaluate the monthly mean soil erosion modulus in Hainan Island over the past two decades, aiming to assess the potential soil erosion risk. The model demonstrated a relatively high R², with validation results for the three basins yielding R² values of 0.77, 0.64, and 0.78, respectively. The results indicated that the annual average soil erosion modulus was 92.76 t·hm⁻²·year⁻¹, and the monthly average soil erosion modulus was 7.73 t·hm⁻²·month⁻¹. The key months for soil erosion were May to October, which coincided with the rainy season, having an average erosion modulus of 8.11, 9.41, 14.49, 17.05, 18.33, and 15.36 t·hm⁻²·month⁻¹, respectively. September marked the most critical period for soil erosion. High-erosion-risk zones are predominantly distributed in the central and eastern sections of the study area, gradually extending into the southwest. The monthly average soil erosion modulus increased with rising elevation and slope. The monthly variation trend in rainfall erosivity factor had a greater impact on soil water erosion than vegetation cover and biological practice factor. The identification of dynamic factors is crucial in areas prone to soil erosion, as it provides a scientific underpinning for monitoring soil erosion and implementing comprehensive water erosion management in these regions.