Aquatic Nutrient Cycling

by

Cédric Leo Meunier, Maarten Boersma

• LAST REVIEWED: 24 May 2017
• LAST MODIFIED: 24 May 2017
• DOI: 10.1093/obo/9780199830060-0177

Introduction

In ecology, the use, transformation, movement, and reuse of nutrients in ecosystems is referred to as nutrient cycling. Nutrient cycles are part of the earth’s Biogeochemistry (Refer Oxford Bibliographies article in Environmental Science). This movement of nutrients is a vital environmental function that influences and is influenced by the organisms inhabiting any given ecosystem. The aquatic systems, streams, lakes, and coastal areas transport and store nutrients and energy from local to continental scales over periods ranging from weeks to millennia. However, aquatic nutrient cycles are particularly vulnerable to change and, for example, altered nutrient inputs can degrade habitat quality and indirectly influence ecosystem productivity and diversity. This topic is partly covered in the Oxford Bibliographies in Environmental Science article River Pollution. For this reason, nutrient cycling is one of the most significant processes studied by aquatic ecosystem ecologists. Most studies consider different nutrient cycles and different ecosystems independently. In nature, however, terrestrial, freshwater, and marine systems are all connected by nutrient flows. Currently, human activities strongly influence nutrient cycles by removing nutrients from the land and discharging them into aquatic environments, leading to eutrophication of water sources. Furthermore, global change processes such as warming, deoxygenation, and acidification are also affecting cycling. Students or scientists interested in pursuing research in aquatic nutrient cycling will therefore have to integrate information from various fields including ecology, physiology, and biochemistry.

General Overviews

The best-studied aquatic nutrient cycles are those of carbon, nitrogen, and phosphorus. These are, however, not the only biologically relevant nutrients and some micronutrients, such as Fe and Se, can in some cases be limiting. Although Hansell and Carlson 2014 is an important text on cycling of marine dissolved organic carbon, nitrogen, and phosphorus, Battin, et al. 2009; Galloway, et al. 2004; and Ruttenberg 2003 provide more detailed overviews of each of these three cycles. Elser, et al. 2007 is a meta-analysis of nitrogen and phosphorus limitation of primary producers. Grimm, et al. 2003 is a review article unifying perspectives of nutrient biogeochemistry in freshwater, marine, and terrestrial systems. Vanni 2002 is a review of the role freshwater animals play in nutrient cycling. Interestingly, most concepts presented in Vanni 2002 are applicable to marine systems. Andersen 2013 is a textbook that presents how nutrient cycling models can be used as management tools. Smith, et al. 1999 is a review that presents the consequences of eutrophication. In this context it is important to consider to which extent human activities can influence nutrient cycles without damaging the environment. This topic is covered by Steffen, et al. 2015.

• Andersen, T. 2013. Pelagic nutrient cycles: Herbivores as sources and sinks. New York: Springer Science and Business Media.

  A textbook presenting how nutrient cycling models can be used as management tools.

• Battin, T. J., S. Luyssaert, L. A. Kaplan, A. K. Aufdenkampe, A. Richter, and L. J. Tranvik. 2009. The boundless carbon cycle. Nature Geoscience 2:598–600.

  DOI: 10.1038/ngeo618

  A concise and well-written article giving an overview of the carbon cycle. The role of inland waters in processing organic carbon is emphasized.

• Elser, J. J., M. E. Bracken, E. E. Cleland, et al. 2007. Global analysis of nitrogen and phosphorus limitation of primary producers in freshwater, marine and terrestrial ecosystems. Ecology Letters 10:1135–1142.

  DOI: 10.1111/j.1461-0248.2007.01113.x

  A meta-analysis is conducted to test whether primary producers in different ecosystems are nitrogen or phosphorus limited. This article nicely presents how organisms affect (and are affected by) nutrient cycles.

• Galloway, J. N., F. J. Dentener, D. G. Capone, et al. 2004. Nitrogen cycles: Past, present, and future. Biogeochemistry 70:153–226.

  DOI: 10.1007/s10533-004-0370-0

  A paper presenting the natural and anthropogenic controls on the conversion of unreactive N₂ to more reactive forms of nitrogen. This article also gives a good overview of the nitrogen cycle and nitrogen budgets in terrestrial and aquatic systems.

• Grimm, N. B., S. E. Gergel, W. H. McDowell, et al. 2003. Merging aquatic and terrestrial perspectives of nutrient biogeochemistry. Oecologia 137:485–501.

  DOI: 10.1007/s00442-003-1382-5

  A well-written article that explains the differing viewpoints of nutrient biogeochemistry in freshwater, marine, and terrestrial systems.

• Hansell, D. A., and C. A. Carlson. 2014. Biogeochemistry of marine dissolved organic matter. San Diego, CA: Academic Press.

  A good textbook provide general overviews on dissolved carbon, nitrogen, and phosphorus marine cycles.

• Ruttenberg, K. 2003. The global phosphorus cycle. Treatise on Geochemistry 8:682.

  An overview of the phosphorus cycle is given. This is a good source of information for students.

• Smith, V. H., et al. 1999. Eutrophication: Impacts of excess nutrient inputs on freshwater, marine, and terrestrial ecosystems. Environmental Pollution 100:179–196.

  DOI: 10.1016/S0269-7491(99)00091-3

  A review presenting the causes and consequences of eutrophication. This article gives a good overview of the eutrophication problem.

• Steffen, W., K. Richardson, J. Rockström, et al. 2015. Planetary boundaries: Guiding human development on a changing planet. Science 347:1259855.

  DOI: 10.1126/science.1259855

  The concept of planetary boundaries is presented by posing the question: are we outside safe operating limits for nitrogen and phosphorus discharge?

• Vanni, M. J. 2002. Nutrient cycling by animals in freshwater ecosystems. Annual Review of Ecology and Systematics 33:341–370.

  DOI: 10.1146/annurev.ecolsys.33.010802.150519

  A review of the role freshwater animals play in nutrient cycling. Although this manuscript focuses on freshwater systems, the physiological and ecological notions presented can be used to study consumer driven nutrient recycling in marine systems.