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Microbiologically Induced Calcite Precipitation Mediated by Sporosarcina pasteurii
Published on: April 16, 2016
Does calcite encrustation in Chara provide a phosphorus nutrient sink?
1Department of Environmental Science and Human Engineering, Saitama University, 255 Shimo-okubo, Sakura-Ku, Saitama 338-8570, Japan. 03D5052@post.saitama-u.ac.jp
Journal of Environmental Quality
|February 4, 2006
Summary
Calcite encrustation in stoneworts (Chara spp.) enhances phosphorus (P) storage by co-precipitating P with calcite. This process stabilizes Chara dominance in aquatic ecosystems by limiting P availability.
Area of Science:
- Aquatic Ecology
- Biogeochemistry
- Limnology
Background:
- Stoneworts (Chara spp.) are crucial aquatic macrophytes.
- Calcite encrustation is a common feature of Chara.
- Phosphorus (P) cycling significantly impacts aquatic ecosystem health.
Purpose of the Study:
- To investigate the role of calcite encrustation in Chara spp. on phosphorus cycling.
- To quantify P fractions in calcified and uncalcified Chara fibrosa.
- To understand how calcification affects P bioavailability and Chara's ecological role.
Main Methods:
- Studied Chara fibrosa with and without calcite encrustation.
- Employed sequential fractionation to quantify phosphorus fractions.
- Analyzed P content in calcified (Ca-CF) and uncalcified (UCa-CF) internodes.
Main Results:
- Calcified Chara (Ca-CF) stored significantly more P than uncalcified (UCa-CF).
- 14-23% of total P in Ca-CF was co-precipitated with calcite, versus 2-3% in UCa-CF.
- Increased total P in Ca-CF did not lead to higher release of bioavailable P fractions.
Conclusions:
- Extracellular calcification in Chara acts as a significant nutrient sink for phosphorus.
- Calcification enhances bottom-up control of phytoplankton by limiting P availability.
- Calcite encrustation in Chara represents a positive feedback mechanism stabilizing Chara dominance in lakes.
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