SBS Informal Seminar
-
This is a past event
Informal seminar: Biotic and abiotic drivers of soil inorganic carbon accumulation in global drylands
For our next informal seminar, Dr Kirsten Ball, will be giving an informal seminar on “Biotic and abiotic drivers of soil inorganic carbon accumulation in global drylands” next Tuesday 7th November at 1 pm in Cruickshank Room G27. Synopsis: Pedogenic processes mediating carbonate distribution in dryland soils may be far more complex than previously thought. It is possible, that these primarily abiotic processes are significantly influenced by the presence of living organisms, who are in turn influenced by their environment. Factors that may interact to influence the dissolution and reprecipitation of carbonates in the natural soil environment include rainfall, temperature and pH, organic acid/carbon inputs from plant growth, and microbially mediated organic matter decomposition. However, while the focus is usually on how biotic processes unidirectionally contribute to soil organic carbon, little attention is being paid to the inorganic carbon pool, the potential for SOC-SIC interactions, and how the organic and inorganic carbon pools may be dynamically influencing one another. The overall aim of this study was to understand the major biotic and abiotic drivers of soil inorganic carbon in global drylands. To achieve this, we quantified SIC content from 332 individual rangeland sites spanning every continent. Dryland rangelands are defined as areas with natural or semi-natural vegetation that provide suitable habitat for herds of wild or domestic ungulates and have an aridity index below 0.65. We used stepwise linear mixed effects regression analyses to distinguish individual and interactive climate, soil geochemical, and biological controls on SIC accumulation. From these analyses, we demonstrate that distinct processes of SIC accumulation are operating at acid-neutral and neutral-alkaline pH ranges. From a biotic perspective, the mechanisms highlight the importance of both plant and microbial driven processes of SIC accumulation. Further, we show that these biotic mechanisms interact significantly with climate and soil geochemistry to determine the SIC response. This knowledge, as it emphasizes the previously undervalued significance of microbial and plant-driven processes in SIC accumulation, also highlights the potential for proactive management of SIC by land managers under varying soil pH conditions, opening new avenues for the intentional and informed management of this critical component of the global carbon pool.
- Speaker
- Dr Kirsten Ball
- Venue
- Cruickshank Room G27.
- Contact
-
Microsoft Teams meetingJoin on your computer, mobile app or room deviceClick here to join the meeting