未经评估:分散个体有助于长期人口持续存在,但需要足够程度的景观连通性。迄今为止,连通性主要是使用最小成本分析和电路理论进行研究的,这两种方法做出了几乎不适用于分散的假设。虽然这些假设可以通过明确模拟整个景观的扩散轨迹来放松,这种模拟缺乏统一的方法。
未经评估:这里,我们提出并应用了一种简单的三步方法来模拟扩散,并使用经验的GPS运动数据和一组栖息地协变量来评估连通性。
未经评估:在提议的方法的第一步中,我们使用集成的步长选择函数来拟合机械运动模型,该模型描述了分散个体的栖息地和运动偏好。在第二步中,我们应用参数化模型来模拟整个研究区域的扩散。在步骤三,我们得出了三个互补的连通性图;一个突出显示频繁遍历区域的热图,中间度地图精确定位分散走廊,以及斑块间连通性图,表明栖息地斑块之间功能联系的存在和强度。我们在一个案例研究中证明了拟议的三步方法的适用性,在该案例研究中,我们使用收集的GPS数据散布居住在博茨瓦纳北部的非洲野狗(Lycaonpictus)。
UNASSIGNED:使用步长选择函数,我们成功地参数化了一个详细的分散模型,该模型描述了分散个体的栖息地和运动偏好,以及两者之间潜在的相互作用。该模型大大优于省略此类相互作用的模型,使我们能够模拟整个研究区域的80,000个扩散轨迹。
未经评估:通过明确模拟扩散轨迹,我们的方法不仅需要更少的关于分散的不切实际的假设,但也允许计算多个连接度量,这些度量共同提供景观连接的全面视图。在我们的案例研究中,得出的三个连通性图揭示了我们研究区域范围内的几个野狗扩散热点和走廊。每张地图都突出了景观连通性的不同方面,从而强调它们的互补性。总的来说,我们的案例研究表明,基于模拟的方法提供了一个简单而强大的替代传统的连接建模技术。因此,它可用于生态中的各种应用,进化,和保护研究。
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UNASSIGNED:在线版本包含补充材料,可在10.1007/s10980-023-01602-4获得。
UNASSIGNED: Dispersal of individuals contributes to long-term population persistence, yet requires a sufficient degree of landscape connectivity. To date, connectivity has mainly been investigated using least-cost analysis and circuit theory, two methods that make assumptions that are hardly applicable to dispersal. While these assumptions can be relaxed by explicitly simulating dispersal trajectories across the landscape, a unified approach for such simulations is lacking.
UNASSIGNED: Here, we propose and apply a simple three-step approach to simulate dispersal and to assess connectivity using empirical GPS movement data and a set of habitat covariates.
UNASSIGNED: In step one of the proposed approach, we use integrated step-selection functions to fit a mechanistic movement model describing habitat and movement preferences of dispersing individuals. In step two, we apply the parameterized model to simulate dispersal across the study area. In step three, we derive three complementary connectivity maps; a heatmap highlighting frequently traversed areas, a betweenness map pinpointing dispersal corridors, and a map of inter-patch connectivity indicating the presence and intensity of functional links between habitat patches. We demonstrate the applicability of the proposed three-step approach in a case study in which we use GPS data collected on dispersing African wild dogs (Lycaon pictus) inhabiting northern Botswana.
UNASSIGNED: Using step-selection functions we successfully parametrized a detailed dispersal model that described dispersing individuals\' habitat and movement preferences, as well as potential interactions among the two. The model substantially outperformed a model that omitted such interactions and enabled us to simulate 80,000 dispersal trajectories across the study area.
UNASSIGNED: By explicitly simulating dispersal trajectories, our approach not only requires fewer unrealistic assumptions about dispersal, but also permits the calculation of multiple connectivity metrics that together provide a comprehensive view of landscape connectivity. In our case study, the three derived connectivity maps revealed several wild dog dispersal hotspots and corridors across the extent of our study area. Each map highlighted a different aspect of landscape connectivity, thus emphasizing their complementary nature. Overall, our case study demonstrates that a simulation-based approach offers a simple yet powerful alternative to traditional connectivity modeling techniques. It is therefore useful for a variety of applications in ecological, evolutionary, and conservation research.
UNASSIGNED: UNASSIGNED: The online version contains supplementary material available at 10.1007/s10980-023-01602-4.