Ecosystem Impacts of Changing Sex Ratios in Lampreys Based on Multi-Model Analysis

Abstract

Through constructing different models, comprehensive research has been conducted on the adaptability of Lampreys and the impact of sex ratio changes on their population and ecosystem. Firstly, an established population dynamics model based on Lotka-Volterra was used to simulate the predation relationships between lampreys and other organisms in the ecosystem. The model was employed to investigate the impact of sex ratio changes in lampreys on the population dynamics of other organisms in the ecosystem. Secondly, an established model was utilized to analyze the relationship between resource availability and sex ratio, further refining the population dynamics model. The population dynamics of this model were tested and compared under different adverse conditions with a model where the sex ratio remains constant. After that Introducing a new participant, aquatic plants, to the population dynamics model formed a simple food chain model. The eigenvalues of the Jacobian matrix were calculated to assess the stability of the food chain model. Further introducing a new participant, aquatic plants, into the population dynamics model formed a simple food chain model. The eigenvalues of the Jacobian matrix were calculated to assess the stability of the food chain model. Finally, the Entropy Weighting TOPSIS model was employed to evaluate the advantages and disadvantages of other species in the ecosystem under changes in the lamprey’s sex ratio. The final results indicated 0.59 points for aquatic plants, 0 points for herbivores, and 1 point for parasites. Through the research using the above methods, it can be concluded that changes in the sex ratio of Lampreys have different impacts on various aspects of the ecosystem. For Lampreys themselves, changes in sex ratio favor the stability of their own population numbers. As for the producers, changes in Lamprey sex ratio provide advantageous conditions. Herbivorous animals involved in predation relationships will experience negative effects. Parasites engaged in competitive relationships will maintain dynamic equilibrium in their interrelationships.