Ecology and biogeochemistry

We have international expertise in environmental microbiology, marine biology and theoretical ecology with specific focus on spatial and temporal patterns of biodiversity, its functional role, the ecological processes that govern the distribution and richness of species in the environment and the eco-physiological mechanisms that enable species to exist across environmental gradients.

Biogeochemistry enables experimental and study-based approaches to better understand nutrient exchange within and between systems and the mechanisms that govern how biology interacts with the physio-chemical environment. With our ecology and biogeochemistry research, we can ensure that society benefits from research efforts in areas such as bioremediation, system productivity, biodiversity enhancement and informing management to better protect natural resources.

• Environmental microbiology

  Microbes are the most abundant and functionally diverse organisms on Earth, providing an array of valuable products and performing vital ecosystem services from the production of oxygen to degradation of pollutants.

  From all three domains of life, the Eukarya, Bacteria and Archaea microbes are investigated within our School of Biological Sciences. Research is conducted over a wide range of biological scales from molecular (genomic, transcriptomic, proteomic), through the organism to the community and ecosystem.

  We are renowned for research into primary productivity and biogeochemical cycling, particularly of nitrogen, carbon and climate-altering gases, in marine and coastal ecosystems. However, a variety of environments come under investigation such as:

  • extreme environments (hypersaline lakes, sea ice and Arctic lakes);
  • rivers;
  • soils;
  • deserts; and
  • hydrocarbon-polluted environments.

  Investigating the interactions of microbes with plants, animals and other microbes forms an important component of our research. Having a better understanding of the adaptation mechanisms of microbial species and communities to changing environmental conditions and how this alters their activities, allows us to tackle global problems like pollution, eutrophication, ocean acidification and climate change.

• Marine biology

  This group conducts world-class research from the poles to the tropical reef systems of the Pacific, Indian and Atlantic oceans. Activities span ecosystems from estuarine and coastal environments and shore waters through to oceanic systems. Much of this research activity is field-based within the UK and through international partnerships with collaborators from universities, government bodies, NGOs and industry.

  The marine biology research group capitalises on our state-of-the-art research laboratories including our:

  • tropical aquarium facility;
  • bioimaging suite;
  • molecular laboratory;
  • omics and bioinformatics suite; and
  • photosynthesis and eco-physiology laboratory.

  We strive to increase society's understanding of these key drivers:

  • productivity and biodiversity; and
  • the pairing of biological process and the environment.

• Mathematical and theoretical ecology

  Interdisciplinary researchers in our group focus on combining aspects of biological sciences with mathematical and theoretical approaches to answer exciting questions in ecology. We work at all levels of biological organisation, from examining resource allocation in cells and modelling the movement and behaviour of individuals, through to examining population and community-level dynamics which underpin patterns of biodiversity. Our group consists of three members of academic staff (Geider, Codling and Dumbrell), who supervise the research and career development of numerous postdoctoral scientists, postgraduate researchers and technical staff, within our School of Biological Sciences and Department of Mathematical Sciences.

Plant productivity

The demands of a growing world population for food and fuel are putting greater pressure on the need for higher yielding crop varieties that do not rely on a high input and demand of chemicals or water. We respond to this challenge by taking a whole organism approach to identify key genes and processes that determine productivity in plants and marine algae in constantly changing environmental conditions. A group of seven, we are supported by a lively team of research technicians, postdoctoral researchers and research students, who create a stimulating collaborative and dynamic research environment.

• Photosynthesis

  Our photosynthesis research includes studies aimed at identifying the impact of environmental factors such as light, temperature and nutrients on productivity. One area of focus is the regulation and integration of carbon assimiliation with wider metabolism and how it impacts on plant growth and development.

  We continue to play a pioneering role in the development and application of chlorophyll fluorescence and imaging technology to monitor photosynthesis and its related functions. Recently, we combined images of photosynthetic efficiency and the rate of evaporative water loss (transpiration), allowing non-invasive assessment of the efficiency of water use by plants. This technology provides a non-invasive and rapid approach to the identification of plant varieties with variation in photosynthetic ability. This, together with our ability to apply a combination of genetic and proteomic approaches, allows the identification of genes that determine these differences in photosynthetic characteristics.

• Crop productivity

  Crop yield is ultimately determined by photosynthetic productivity which is then impacted on by environmental factors. Research at Essex focuses on both of these limitations.

  We have a major research effort aimed at improving leaf photosynthetic carbon assimilation. This focuses on manipulating the enzymes of the Calvin cycle through the integration of fixed carbon into cellular metabolism to increase crop productivity. One of the most important environmental limitations on crop productivity is water supply.

  How drought conditions are first detected and acted upon by a plant is of great importance as this will influence when growth stops. Studies using the model plant thale cress have shown when the plant first physiologically responds to the onset of drought, the metabolic changes that accompany these early events and the coordinated changes in genome expression that underline these responses. Candidate genes controlling this process have been identified using computational techniques, and plants with modified expression of these genes are being studied for their response to the early stages of drought stress.

  Water productivity is an important crop trait, which is the crop yield obtained for water consumed throughout the plant’s life. Plant varieties that have enhanced water productivity have been identified and genes that control this trait have been transferred from thale cress to brassica crops for evaluation in the lab and in the field.

• Plant and cell signalling

  Intra- and intercellular signalling provides the connection between perception of and response to environmental stress. At our University, we are dissecting signaling pathways that respond to environmental stress. In particular, we are interested in how the circadian clock, hormones and reactive oxygen species (ROS) communicate in signaling networks.

  Bundle sheath cells in the leaf sense changes in light intensity by increasing ROS in their chloroplasts, which triggers rapid changes in gene expression. We have shown that the signaling is driven by a complex interaction between the hormone abscisic acid (ABA) and ROS. It turns out that ABA is a determinant of how well leaves adjust to changes in light intensity because of this signaling in bundle sheath cells and other tissues.

  Current research extends to studying gene networks that control acclimation to high light with many new genes identified using computational analysis of gene expression data. The regular transition between day and night provides important information that can inform plants of likely stresses, and life has evolved to anticipate these challenges. The circadian clock is an endogenous timing mechanism that confers an adaptive advantage through the prescient accumulation of protective metabolites in anticipation of stresses throughout the day. At Essex, we are studying the ability of the clock to control stress signaling pathways in response to stresses applied at different times of the day. By better understanding these mechanisms, we aim to optimize stress tolerance in our changing environment in order to maximize crop productivity.