2024-B19 Insect responses to climate change in woodland systems

Overview

Simulating the impacts of future climate change at an ecosystem level is extremely challenging. One of the few experiments globally investigating this in forest systems, and the only one for mature deciduous woodland, is the Birmingham Institute of Forest Research (BIFoR) Free Air Carbon dioxide Enrichment (FACE) facility1. This institute brings together a unique research community, as well as a broad range of stakeholders and policy makers.  The BIFoR FACE experiment is an exceptional experimental facility in which to study for a PhD.   

Insect biodiversity is in decline globally, and understanding the cause of this decline has applications in food security, conservation and human health. This project builds on 7 years of data at the FACE site to examine how elevated CO2 (eCO2), and recent extreme climate events, have impacted on insect diversity, abundance and phenology. Because insects are ectotherms, their development and population growth are directly influenced by temperature. For insect herbivores and pollinators, all these attributes are indirectly affected by climate change impacts on plants.  

An important knowledge gap remains our limited understanding of how climate warming and eCO2 will alter insect-plant interactions. Our previous work has shown that eCO2 could decouple important plant-pollinator relationships, with plant flowering shifting to earlier in the year (Fig. 1), which may not be matched by changes in pollinator phenology1. Our work at BIFoR has also shown that plant-herbivore interactions may change and could significantly alter nutrient cycling processes (Roberts et al. 2022). We have already identified several excellent model insect systems to examine eCO2 impacts on herbivory, e.g. leaf miners, which undergo all development and metamorphosis in a single leaf. This allows us to accurately quantify both rates of development and levels of herbivory through image analysis of leaves. Determining the chemical responses of plants to enhanced herbivory under eCO2 remains poorly understood and is likely to form an important part of the programme. 

As well as building on existing studies, there is huge scope for the successful applicant to develop their own new research questions, with huge potential for collaboration with other researchers as well as stakeholders and policy makers linked to BIFoR.  

Figure 1: Daily mean totals of bluebell (Hyacinthoides non-scripta) flowers per patch area (m2) under elevated CO2 and ambient conditions at the BIFoR FACE site. Elevated CO2 has clearly advanced bluebell flowering time.