Elemental cycles that sustain life and climate
Human activities are dramatically influencing the delicate balance of crucial elements in the Earth’s systems, leading to changes in the complex biogeochemical cycles of carbon, phosphorus, nitrogen and sulphur. These elements are the most important for biological systems and often are limiting factors to the survival of organisms. These elements exist in a variety of forms, for example, as gaseous compounds in the atmosphere, the cells of living organisms, or dissolved in seawater.
Components of these cycles participate at both the molecular and global levels. Crucially, however, some of the elements exist in compounds known to be major drivers of global climate change. This, in turn, has a direct impact on the geochemical cycles in which the elements participate. The entire cycle therefore responds to the levels of the compounds and hence global biogeochemistry is altered. As a consequence, the sustainability of entire terrestrial and aquatic ecosystems is potentially under threat.
Within the Alliance, an understanding of the individual biological processes at the cellular level in plants and microbes is being integrated with extensive knowledge of global biogeochemical cycles. JIC has an excellent, long-standing research reputation around biological nitrogen fixation and carbon utilisation in plants, and new research programmes are underway focussing on the uptake of sulphur and phosphorus by plants. UEA is internationally renowned for its expertise in climate system analysis, global biogeochemical cycling and Earth System modelling.
Combining the expertise of these two institutions allows an integrated study of natural biological processes involved in elemental cycling, as well as an understanding of their roles throughout evolution. A better understanding of the natural processes involved in elemental cycling will hopefully ameliorate the effects of climate change, such as through changes to agricultural systems. This could include, for example, carbon sequestration in soils and sediments, or more efficient use of nitrogen by crops to reduce the levels of fertilisers needed.
The researchers in the elemental cycles pillar are focussing on three areas:
Soil Microbiology and Weathering
UEA research has revealed that long-term weathering processes are regulated in part by plant root exudates and the associated microbial community. In this area, the Alliance is uniquely placed to harness JIC’s expertise in microbe-rhizosphere interactions to understand more fully the fundamental understanding of this process and its role within the whole Earth system.
Biological Nitrogen Fixation
The process by which atmospheric nitrogen is “fixed” into a form which plants can absorb is a major research interest within the Alliance. JIC and UEA bring significant expertise in both terrestrial and marine nitrogen fixation, and this programme will focus on two major themes:
- understanding the fundamental controls on biological nitrogen fixation, and how they are affected by environmental factors (such as ambient nutrient concentration).
- incorporating biological nitrogen fixation into global Earth System models.
Biological Trace Gas Production and Its Impacts
Certain trace gases (dimethyl sulphide, isoprene, methane, nitrous oxide and LMW halogenated gases such as methyl bromide) are significant players in elemental cycles, being involved in, for example, ozone cycling, aerosol formation and greenhouse gas budgets. Research within ELSA is embracing the genetic, biochemical and physiological pathways that underpin production of these trace gases, linking these with biogeochemical cycling at local, ecosystem and global levels.
