The impact of fragmentation on biodiversity is driven by more than the spatial configuration of suitable habitat patches. Habitat is embedded in the surrounding anthropogenic land cover, known as the matrix, which plays a key role in species movement and connects the fragmented habitat. Whether the matrix is a barrier or a conduit to movement depends on the mortality of the moving individuals. However, individuals differ in their behavioural response to the risk posed by the matrix, with the willingness to enter the matrix depending on an individual's risk-taking behaviour. This individual-level behavioural variability is rarely considered but represents an additional mechanism shaping inter- and intraspecific competition as well as evolutionary behavioural responses. We used an individual-based model to scale up from individual foraging movements to the resulting community structure of a competitive small mammal community in differently fragmented landscapes. The model interactively considers extrinsic matrix conditions, given as a certain mortality rate, and individual differences in intrinsic movement decisions when moving into the matrix. The model was used to investigate consequences of fragmentation and matrix mortality for species and behavioural diversity. Low matrix mortality resulted in a positive effect of fragmentation on species diversity. At the same time, it led to a high average risk-taking behaviour. While this was an important adaptive response to fragmentation, it also led to a loss of intraspecific diversity. High matrix mortality reversed the effect of fragmentation, leading to a drastic loss of species with increasing fragmentation. High mortality risk reduced average risk-taking, especially at high fragmentation. Study findings suggest that the feasibility of movement in the matrix can influence species diversity and evolutionary responses of movement-related behavioural traits in fragmented landscapes. The matrix may thus play a key role in reconciling contrasting empirical results and provides a promising tool for future biodiversity conservation.

中文翻译：

---

冒险行为的变化介导了基质死亡率对破碎化下生物多样性的影响


破碎化对生物多样性的影响不仅仅取决于适宜栖息地斑块的空间配置。栖息地嵌入在周围的人为土地覆盖中，称为基质，它在物种运动中起着关键作用，并连接着破碎的栖息地。基质是移动的障碍还是管道，取决于移动个体的死亡率。然而，个体对矩阵带来的风险的行为反应不同，进入矩阵的意愿取决于个体的冒险行为。这种个体水平的行为变异很少被考虑，但代表了塑造种间和种内竞争以及进化行为反应的另一种机制。我们使用基于个体的模型，从个体觅食运动扩大到在不同碎片化景观中形成的竞争性小型哺乳动物群落的群落结构。该模型以交互方式考虑外在矩阵条件（以一定的死亡率给出）以及进入矩阵时内在运动决策的个体差异。该模型用于研究碎片化和基质死亡率对物种和行为多样性的影响。低基质死亡率导致碎片化对物种多样性产生积极影响。同时，它导致了较高的平均冒险行为。虽然这是对碎片化的重要适应性反应，但它也导致了种内多样性的丧失。高基质死亡率逆转了碎片化的影响，导致物种急剧损失，碎片化程度增加。高死亡风险降低了平均风险承担，尤其是在高度碎片化的情况下。 研究结果表明，矩阵中运动的可行性可以影响碎片化景观中物种多样性和运动相关行为特征的进化反应。因此，该矩阵可能在调和对比鲜明的实证结果方面发挥关键作用，并为未来的生物多样性保护提供有前途的工具。