Theoretical framework, indicator system and practical application of key biodiversity areas

With the continuous decline of global biodiversity, biodiversity conservation has attracted more and more attention from the international society. In order to slow down the trend of biodiversity decline, it is particularly important to identify key areas for biodiversity conservation. However, most of current methods for identifying important areas have different assessment criteria and focus on different biological assemblages (species or communities) and ecosystem types. Key biodiversity areas (KBAs) are sites that contribute significantly to global biodiversity persistence. Unlike traditional research and identification methods, KBAs identification is based on a unified global standard to explore habitats that are critical to endangered plants and animals in terrestrial, freshwater, and marine ecosystems. Based on the theoretical and technical framework of KBAs, we summarized the system of identification criteria and assessment parameters for KBAs. The five high-level criteria are separated into eleven sub-level criteria. Among the eleven evaluation parameters, there is one evaluation parameter for the ecosystem level, eight evaluation parameters for the species level, one evaluation parameter for the gene level, and one comprehensive evaluation parameter. In addition, we analyzed the application of KBAs identification in biodiversity research and conservation combined with relevant domestic and foreign research cases. Furthermore, we discussed the future development direction and application prospect of KBAs identification method in China. This method could provide a new perspective for the formulation of ecological protection policies and the planning of naturally protected areas in China.

[Evaluation of ecological conservation red line from the perspective of ecological security pattern: Taking Zhejiang Province, China as an example]

To investigate the scientificity of the ecological conservation red line in Zhejiang Province, we evaluated the ecological effect based on the concept of ecosystem processes from the perspective of ecological security pattern. On the basis of clarifying the triple connotation of the ecological conservation red line, we constructed an evaluation index system to identify ecological sources and evaluate the importance of red line patches with InVEST model and net primary productivity quantitative analysis. Minimum resistance model and gravity model were used to construct the ecological corridors and evaluate the connectivity of red line. Moreover, landscape pattern index and overlay analysis were applied to evaluate the fragmentation and coordination of red line. The results showed that, from the perspective of ecological importance, the protection scale in Zhejiang Province was relatively large, but 13.5% of the red line areas were not of high importance. About 40% of the provincial ecological sources were not included in the ecological conservation red line. From the perspective of spatial structure, the connectivity of the ecological conservation red line was insufficient. The protection rate of the first-level ecological corridor was less than 15%. The red line patches in some counties and cities were relatively broken. From the perspective of natural-social system coordination, cross-administrative red line areas were well connected. However, it was still necessary to pay attention to the fact that the conflict between supply and demand in the plain area had led to spatial mismatch and fragmentation of red line. Using the ecological security pattern for reference, we put forward the relevant strategies of red line optimization and adjustment, which could provide scientific reference for ecological space management.

Spatial Pattern Change and Ecosystem Service Value Dynamics of Ecological and Non-Ecological Redline Areas in Nanjing, China

Ecological conservation red line (ECRL) is gaining increasing academic attention as delimiting the minimum space scope of ecological protection and the bottom line of ecological security. Taking Nanjing as a case study, we divided the territory into ecological and non-ecological redline areas (ERAs and NERAs, respectively). This paper highlights two key research issues based on the 2005, 2010, 2015 and 2018 annual remote sensing data: (i) quantitative analysis of the Ecological Redline Policy (ERP) validity by conducting a horizontal comparison of the ERAs and NERAs; and (ii) exploration of the land-use transitions and spatial pattern changes affecting ecosystem service value (ESV). Results showed that delineating ECRL could effectively slow down the decline rate of ESV. The trend of eco-quality deterioration was greater than eco-quality improvement in Nanjing, presenting an ESV that declined slightly in the whole. According to our findings, we suggest that reasonably increasing eco-lands (woodland and water area) and decreasing construction land will enhance the regional ESV. Meanwhile, promoting the transition from production space to ecological space and depressing the encroachment of living space on other space types, will be instrumental in mitigating the ESV decline. The results of this study are expected to provide valuable implications for spatial planning and sustainable development in Nanjing.