Projects per year
Abstract
Long-term ecosystem development is characterized by a switch from nitrogen (N) to phosphorus (P) limitation of plant communities as soils age, which leads to changes in plant biomass, diversity, and foliar nutrient concentrations. Similar effects occur belowground, although the extent to which nutrient availability is the primary driver of long-term changes in soil microbial communities remains uncertain. To investigate this, we assessed proxies for soil microbial nutrient limitation along the Jurien Bay dune chronosequence in Western Australia, where a long-term decline in P availability is reflected in strong variation in plant and microbial community composition over 2 million years of soil development. We quantified carbon (C), N, and P in the soil microbial biomass, assayed soil enzymes involved in the acquisition of those nutrients from soil organic matter, and used microbial stoichiometric ratios and vector analysis of enzyme activities to assess whether long-term changes in soil nutrient availability are reflected in nutrient demand by soil microbes. Concentrations of microbial nutrients peaked in Holocene soils (1–6.5 ky), although differences in microbial P were not significant. There were no significant differences in microbial nutrient ratios (C:N, C:P, and N:P) along the chronosequence. Acid phosphatase activity increased continually throughout the chronosequence, while the activities of leucine aminopeptidase and β-glucosidase were greatest in Holocene soils and declined with increasing soil age. Corresponding vector lengths indicated greater investment in C-degrading enzymes in Holocene soils (≤6.5 ky), while vector angles indicated greater investment in the acquisition of P compared with N in Pleistocene soils (≥120 ky). Overall, these findings show that changes in nutrient availability during long-term pedogenesis at Jurien Bay are reflected in microbial investment in nutrient acquisition, but that the soil microbial biomass exhibits a remarkable degree of homeostasis despite major shifts in nutrient availability and community composition over 2 million years of ecosystem development.
Original language | English |
---|---|
Article number | 109385 |
Number of pages | 11 |
Journal | Soil Biology and Biochemistry |
Volume | 192 |
Early online date | 11 Mar 2024 |
DOIs | |
Publication status | Published - May 2024 |
Fingerprint
Dive into the research topics of 'Microbial nutrient limitation along a 2-million-year dune chronosequence'. Together they form a unique fingerprint.Projects
- 4 Finished
-
Facilitation of high leaf phosphorus-use efficiency by nitrate restraint
Lambers, H. (Investigator 01), Finnegan, P. (Investigator 02) & Dassanayake, M. (Investigator 03)
ARC Australian Research Council
1/07/20 → 1/07/24
Project: Research
-
Does Calcium Toxicity Explain the Absence of Most Proteaceae from Calcarous Habitats
Lambers, H. (Investigator 01), Clode, P. (Investigator 02), Hammond, J. (Investigator 03) & White, P. (Investigator 04)
ARC Australian Research Council
1/01/13 → 31/12/15
Project: Research
-
Is the Extreme Phosphate Sensitivity Found Among Australian Plants a Consequence of their Adaptation to a Severely Phosphate-Limited Environment?
Lambers, H. (Investigator 01), Finnegan, P. (Investigator 02), Bohnert, H. (Investigator 03), Cheeseman, J. (Investigator 04) & Mast, A. (Investigator 05)
ARC Australian Research Council
1/01/11 → 31/12/13
Project: Research