Interactions of local climatic, biotic and hydrogeochemical processes facilitate phosphorus dynamics along an Everglades forest-marsh gradient

Authors

Tiffany Troxler-Gann, Southeast Environmental Research Center and Department of Biological Sciences, Florida International UniversityFollow
C. Coronado-Molina, South Florida Water Management District
D. N. Rondeau, Everglades National Park
S. Krupa, South Florida Water Management District
S. Newman, South Florida Water Management District
M. Manna, South Florida Water Management District
René M. Price, Southeast Environmental Research Center, Florida International UniversityFollow
F. H. Sklar, South Florida Water Management District

Date of this Version

2-14-2014

Document Type

Article

Rights

by

Abstract

Ecosystem nutrient cycling is often complex because nutrient dynamics within and between systems are mediated by the interaction of biological and geochemical conditions operating at different temporal and spatial scales. Vegetated patches in semiarid and wetland landscapes have been shown to exemplify some of these patterns and processes. We investigated biological and geochemical factors suggested to contribute to phosphorus (P) movement and availability along a forest-marsh gradient in an Everglades tree island. Our study illustrated processes that are consistent with the chemohydrodynamic nutrient (CHNT) hypothesis and the trigger-transfer, pulse-reserve (TTPR) model developed for semiarid systems. Comparison with the TTPR model was constructive as it elaborated several significant patterns and processes of the tree island ecosystem including: (1) concentration of the limiting resource (P) in the source patch (High Head which constitutes the reserve) compared with the resource-poor landscape, (2) soil zone calcite precipitation requiring strong seasonality for evapotranspiration to promote conditions for secondary soil development and calcium phosphate reprecipitation, (3) rewetting of previously dry soils by early wet season precipitation events, and (4) antecedent conditions of the source patch, including landscape position that modulated the effect of the precipitation trigger. Thus, our study showed how water availability drives soil water P dynamics and, potentially, stability of mineral soil P in this tree island ecosystem. In landscapes with extensive water management, these processes can be asynchronous with the seasonality of hydrologic dynamics, tipping the balance between a sink and source of a limiting nutrient.

Comments

Originally published in Biogeosciences.

Creative Commons License

This work is licensed under a Creative Commons Attribution 3.0 License.

Recommended Citation

Troxler, T. G., Coronado-Molina, C., Rondeau, D. N., Krupa, S., Newman, S., Manna, M., Price, R. M., and Sklar, F. H.: Interactions of local climatic, biotic and hydrogeochemical processes facilitate phosphorus dynamics along an Everglades forest-marsh gradient, Biogeosciences, 11, 899-914, doi:10.5194/bg-11-899-2014, 2014.