Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina, USA.
Conserv Biol. 2022 Oct;36(5):e13904. doi: 10.1111/cobi.13904. Epub 2022 Jun 23.
Maintaining and enhancing landscape connectivity reduces biodiversity declines due to habitat fragmentation. Uncertainty remains, however, about the effectiveness of conservation for enhancing connectivity for multiple species on dynamic landscapes, especially over long time horizons. We forecasted landscape connectivity from 2020 to 2100 under four common conservation land-acquisition strategies: acquiring the lowest cost land, acquiring land clustered around already established conservation areas, acquiring land with high geodiversity characteristics, and acquiring land opportunistically. We used graph theoretic metrics to quantify landscape connectivity across these four strategies, evaluating connectivity for four ecologically relevant species guilds that represent endpoints along a spectrum of vagility and habitat specificity: long- versus short-distance dispersal ability and habitat specialists versus generalists. We applied our method to central North Carolina and incorporated landscape dynamics, including forest growth, succession, disturbance, and management. Landscape connectivity improved for specialist species under all conservation strategies employed, although increases were highly variable across strategies. For generalist species, connectivity improvements were negligible. Overall, clustering the development of new protected areas around land already designated for conservation yielded the largest improvements in connectivity; increases were several orders of magnitude beyond current landscape connectivity for long- and short-distance dispersing specialist species. Conserving the lowest cost land contributed the least to connectivity. Our approach provides insight into the connectivity contributions of a suite of conservation alternatives prior to on-the-ground implementation and, therefore, can inform connectivity planning to maximize conservation benefit.
维持和增强景观连通性可以减少因生境破碎化导致的生物多样性下降。然而，对于在动态景观上增强多种物种连通性的保护效果，特别是在长时间尺度上，仍然存在不确定性。我们根据四种常见的保护土地收购策略，即收购成本最低的土地、收购已建立的保护区周围的土地、收购具有高地理多样性特征的土地和机会性收购土地，预测了 2020 年至 2100 年的景观连通性。我们使用图论指标来量化这四种策略下的景观连通性，评估了四个生态相关物种群落在脆弱性和栖息地特异性谱上的四个端点的连通性：长距离与短距离扩散能力以及栖息地专家与一般物种。我们将我们的方法应用于北卡罗来纳州中部，并纳入了景观动态，包括森林生长、演替、干扰和管理。尽管各策略之间的增加情况差异很大，但在所有采用的保护策略下，专门物种的连通性都得到了改善。对于一般物种，连通性的改善可以忽略不计。总体而言，在已指定用于保护的土地周围集中开发新的保护区，可以最大程度地提高连通性；对于长距离和短距离扩散的专门物种，增加的幅度是目前景观连通性的几个数量级。保护成本最低的土地对连通性的贡献最小。我们的方法提供了在实地实施之前了解一系列保护替代方案对连通性的贡献的见解，因此可以为最大限度地提高保护效益的连通性规划提供信息。
