Climate change impacts on arthropod food webs in rice agriculture

Collaborative team: Mike boyle, Ekgachai Jeratthitikul, Patompong Johns Saengwilai, Claas Damken, Louise Ashton

Climate change is destabilising natural and semi-natural systems on which humans rely. Increased temperatures can directly impact the fitness of organisms, but also alter the interactions among species that underpin ecological functions, driving a ‘rewiring of nature’. One of the most fundamental ecological interactions involves the interplay between predators and their prey. A climate change-driven shift in predation pressure could result in changes to herbivore densities and rates of herbivory. This could lead to changes in agricultural ecosystems and impact global food security.  

Rice is a staple food for half of the world’s population, with Asia producing 90% of global supply. The most significant pests of rice are herbivorous insects, which are partially  controlled by predatory insects. As ectotherms, the fitness of these insects are closely tied to environmental temperatures. In the tropics, insects are thought to already exist close to their upper thermal limits. If herbivores are more resilient to increased temperatures than predators, as indicated by data from other ecosystems, it is likely that activity of rice pests will increase with climate change, leading to declines in rice productivity. We need to understand how elevated temperatures attenuate the links between herbivores and predators in rice agriculture in order to predict and mitigate climate change impacts.

Funded by the Hong Kong General Research Grant 2023