期刊
FRESHWATER SCIENCE
卷 36, 期 1, 页码 26-40出版社
UNIV CHICAGO PRESS
DOI: 10.1086/690598
关键词
phosphate uptake; ammonium uptake; non-saturation; biogeochemistry; metabolism; macrophytes; aquatic biofilms
资金
- CONICET
- Agencia Nacional de Promocion Cientifica y Tecnologica [PICT-2011-0163]
- Agencia Espanola de Cooperacion Internacional para el Desarrollo [A1/037685/11]
Nutrient retention has been studied intensively in streams, but some mechanisms and processes are not yet entirely understood, especially in open-canopy streams. We evaluated PO43-, as soluble reactive P (SRP), and NH4+ uptake in 2 chronically enriched Pampean streams with different macrophytic abundance. We performed short-term nutrient additions to quantify SRP and NH4+ uptake metrics throughout the year, and we investigated which hydrological and biological factors influenced nutrient uptake. The results showed that SRP and NH4+ uptakes were high in relation to pristine and impaired streams elsewhere, and they did not saturate despite elevated background nutrient levels. NH4+ areal uptake rate fit in a 1st-order uptake model, but an exponential model described the relationship between SRP areal uptake rate and SRP concentration. Consistent with this finding, SRP uptake velocity tended to increase linearly, and SRP uptake length decreased linearly with SRP concentration. The analysis of factors influencing uptake metrics suggested that SRP uptake mainly depended on heterotrophic demand, whereas NH4+ uptake was enhanced under more autotrophic conditions. Our results showed that nutrient uptake metrics of enriched Pampean streams were similar to those observed in streams with low nutrient levels.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据