Biomaterial Database

Nutrient enrichment homogenizes lake benthic assemblages at local and regional scales. 2009

Ian Donohue, and Andrew L Jackson, and Martin T Pusch, and Kenneth Irvine

School of Natural Sciences, Department of Zoology, Trinity College, Dublin 2, Ireland. ian.donohue@tcd.ie

The compositional heterogeneity of biotic assemblages among sites, or beta-diversity, regulates the relationship between local and regional species diversity across scales. Recent work has suggested that increased harshness of environmental conditions tends to reduce beta-diversity by decreasing the importance of stochastic processes in structuring assemblages. We investigated the effect of nutrient enrichment on the compositional heterogeneity of lake benthic invertebrate assemblages in Ireland at both local (within-lake) and regional (among-lake) scales. At local scales, we found that the compositional heterogeneity of benthic assemblages was related inversely to the extent of nutrient enrichment (as indicated by measurements of water column total phosphorus, total nitrogen, and chlorophyll a), after effects of lake morphology (i.e., surface area, connectivity, and depth of sampling) and alkalinity were accounted for. At regional scales, we found that nutrient-rich lakes had significantly more homogenous benthic assemblages than nutrient-poor lakes, over and above the effect of alkalinity and across a similar range of lake morphologies. These findings have profound implications for global aquatic biodiversity, as the homogenization of benthic assemblages at both local and regional scales may have important and unpredictable effects on whole aquatic ecosystems, with potentially considerable ecological and evolutionary consequences.

UI	MeSH Term	Description	Entries
D007448	Invertebrates	Animals that have no spinal column.	Brachiopoda,Mesozoa,Brachiopodas,Invertebrate,Mesozoas
D009584	Nitrogen	An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.
D010758	Phosphorus	A non-metal element that has the atomic symbol P, atomic number 15, and atomic weight 31. It is an essential element that takes part in a broad variety of biochemical reactions.	Black Phosphorus,Phosphorus-31,Red Phosphorus,White Phosphorus,Yellow Phosphorus,Phosphorus 31,Phosphorus, Black,Phosphorus, Red,Phosphorus, White,Phosphorus, Yellow
D011157	Population Dynamics	The pattern of any process, or the interrelationship of phenomena, which affects growth or change within a population.	Malthusianism,Neomalthusianism,Demographic Aging,Demographic Transition,Optimum Population,Population Decrease,Population Pressure,Population Replacement,Population Theory,Residential Mobility,Rural-Urban Migration,Stable Population,Stationary Population,Aging, Demographic,Decrease, Population,Decreases, Population,Demographic Transitions,Dynamics, Population,Migration, Rural-Urban,Migrations, Rural-Urban,Mobilities, Residential,Mobility, Residential,Optimum Populations,Population Decreases,Population Pressures,Population Replacements,Population Theories,Population, Optimum,Population, Stable,Population, Stationary,Populations, Optimum,Populations, Stable,Populations, Stationary,Pressure, Population,Pressures, Population,Replacement, Population,Replacements, Population,Residential Mobilities,Rural Urban Migration,Rural-Urban Migrations,Stable Populations,Stationary Populations,Theories, Population,Theory, Population,Transition, Demographic,Transitions, Demographic
D002734	Chlorophyll	Porphyrin derivatives containing magnesium that act to convert light energy in photosynthetic organisms.	Phyllobilins,Chlorophyll 740
D005068	Eutrophication	The enrichment of a terrestrial or aquatic ECOSYSTEM by the addition of nutrients, especially nitrogen and phosphorus, that results in a superabundant growth of plants, ALGAE, or other primary producers. It can be a natural process or result from human activity such as agriculture runoff or sewage pollution. In aquatic ecosystems, an increase in the algae population is termed an algal bloom.	Algal Bloom,Algal Blooms,Bloom, Algal,Blooms, Algal,Eutrophications
D005618	Fresh Water	Water containing no significant amounts of salts, such as water from RIVERS and LAKES.	Freshwater,Fresh Waters,Freshwaters,Water, Fresh,Waters, Fresh
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000077194	Chlorophyll A	A form of chlorophyll that absorbs light in the violet to red spectrum (approximately 400-700 nm wavelength range) and reflects green light (500-570 nm wavelength), which imparts the characteristic green color to land plants. It is essential for oxygenic PHOTOSYNTHESIS.	Chlorophyll A2
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia