Impacts of climate-driven evolution on plant-soil interactions and ecosystem functioning

Globally, we depend on grasslands to support biodiversity, ensure agricultural productivity, offer recreational areas, and provide a wide range of other valuable ecosystem services; e.g. the UK dairy industry depends on grasslands and is worth ~£4.27 billion per annum. At the same time, grasslands are among the most altered and least protected biomes, and will inevitably be subjected to the imminent effects of climate changes: warming, drought, flooding.

Organisms within grasslands may ultimately cope with climate change by adapting; either through evolution, where environmental change selects for individuals whose genes encode advantageous characteristics, or by reversible ("plastic") changes in physiology or growth pattern. Only evolution leads to lasting adaptive change. Thus, evolution has the potential to buffer populations against the adverse effects of climate change. However, the wider effects of evolutionary change, on coexisting species within ecosystems, and on important ecosystem functions, such as nutrient cycling, remain unresolved. "Grasslands", for instance, may seem to be composed of just plants, but beneath the surface there is a thriving microbial community (bacteria and fungi) that interacts with plants to influence the diversity and productivity of the vegetation, plant nutrition, and even evolution. With their rapid generation times and massive populations, these microbes evolve rapidly under pressures such as climate change. Consequently, to understand climate-driven impacts in grasslands, it is essential to integrate the effects of evolutionary and ecological processes that occur both above-, and belowground.

Our research will address these pressing issues, by placing climate-driven evolutionary change in an appropriate ecological context. For over two decades, we have exposed a natural UK grassland near Buxton to simulated climate change (warming, increased rainfall, and drought). Our published and preliminary research shows that simulated climate change has already altered plant and microbial communities and has driven evolutionary change within plants.

Building on these previous findings, our overarching goal is to use the Buxton climate change experiment to determine how above- and belowground communities co-evolve, and interact with each other during climate change, to shape ecosystem processes. In doing so, we aim to understand changes in the services that grasslands provide, and offer the means to predict and manage these changes.

We have designed a cohesive set of experiments to examine key issues at levels ranging from genes to ecosystem responses, using laboratory microcosms, growth-chamber experiments, and field manipulations. Over three years, we will: i) examine two ecologically important microbe species from the field site to determine how long-term climate change treatments drive evolution; ii) use microcosms that include microbes and plants to understand how microbial adaptation affects plant fitness and ecosystem function; iii) determine how evolutionary change in plants, in turn, alters microbial species in the soil. We will use a wide range of techniques to reach these goals, from genome sequencing, to identify the genetic basis of evolutionary change in soil microbes, to respiration measurements, to understand how evolution changes the way ecosystems "breathe". Our research will provide a unique, evolutionary view of how plants and soil organisms respond together to climate change, and of resulting shifts in ecosystem-level processes.

Our proposed research will provide an integrated view of evolutionary and ecological responses to climate change. Results from this study will advance our understanding of how plants and soil microbes respond to climate change through evolutionary and ecological mechanisms, and how these responses affect ecosystem function. We will gain novel insights into i) which processes mediate adaptive responses to the climate in soil microbes, ii) what the ecological consequences of these responses may be, and iii) the importance of evolutionary changes in mediating ecological processes, relative to changes in plant and microbial community structure. Our study focuses on calcareous, species-rich grasslands, which support many rare plant species and a rich insect fauna.

Who might benefit from this research? We have identified three key non-academic stakeholder groups:
1: Conservation practitioners, statutory conservation agencies (including Project Partner, Natural England), and other conservation trusts and charities (e.g., the Peak Park Authority, Wildlife Trusts, RSPB, the National Trust) and UK policy-makers such as the Department of Energy and Climate Change, Department of Environment, Food and Rural Affairs.
2. Horticultural businesses and others involved in the production and sale of native seed. This market (£3-6 million value in 2011) is dominated by the production and sale of grassland wildflower mixes and is expected to grow strongly, likely doubling by 2020.
3: General public, who demonstrate a keen awareness of climate change issues and conservation of species-rich UK habitats.

How might they benefit from this research?
1: Practitioners and policy-makers will benefit through an improved understanding of how adaptive genetic variation enhances ecosystem resilience during climate change. Our results will provide an evidence-base to support policy decisions to optimise landscape management strategies and anticipate threats to ecosystem service provision. Our findings will also allow more sensitive modelling of both the current and future capacity of landscapes to provide ecosystem services by incorporating the effects of evolutionary change. By engaging these organisations in knowledge exchange throughout the programme of research, we can ensure that our work will be of value in terms of 'real-world' implementation and impact.
2: Horticultural businesses that supply native seed and seed mixes for habitat restoration could benefit from our project through an improved understanding of climatic impacts on seed restoration success. Our results have the potential to provide the knowledge-base for determining optimal approaches to match the microclimate of seed sources to restoration environments. This provides businesses with increased capacity to develop marketable stress-resistant seed mixtures.
3: The general public stand to gain educational and environmental knowledge benefits from our project, through (i) enhanced awareness of potential climatic impacts on biodiversity and the ecological supply chain that provides ecosystem services, and (ii) an improved understanding of the potential for genetic resilience within natural populations and ecosystems. Public engagement through a variety of media will provide many opportunities to promote the research and increase public interest in climate change adaptation. Our planned low-cost outreach centre and educational activities to promote field-based learning about climate change ecology aim to create a legacy that will outlast the project.