[POS] Ecology and Enviromment

[POS-37] How Do Degree-Correlated Interaction Strengths Shape Biodiversity?

*Hae Seong Lee¹, Deok-Sun Lee², Sang Hoon Lee³, Hye Jin Park¹ (1. Inha University (Korea), 2. Korea Institute for Advanced Studies (Korea), 3. Gyeongsang National University (Korea))

Keywords:

Complex system,Lotka-Volterra model,Complex networks

In ecological systems where species interact in complex networks, it is known that hub species play a crucial role in shaping biodiversity. Their strong influence is typically attributed to their high number of connections, assuming uniform interaction strengths across the network. However, in many ecological systems, interaction strengths between species often correlate with the number of connections a species has. In this study, we introduce degree-dependent interaction strengths into the generalized Random Lotka-Volterra model to investigate how these variations shape biodiversity. Specifically, we assume that the interaction strength between species i and j follows an independent Gaussian distribution: J_ij ~N(μk_i^αk_j^β, σ²k_i^αk_j^β), where k_i and k_j are the degrees of species i and j, respectively. Under the constraints α, β ∈ [-1,0] and α + β = -1, high-degree species interact more weakly with others and experience reduced influence. Our findings suggest that incorporating degree-dependent interactions mitigates the influence of hubs, reducing species extinctions in cooperative communities and enhancing the stability of the system.