NutrientLoading: Difference between revisions
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A new study has shown that reefs overgrown with algae or characterized by coral rubble send chemical cues that repel juvenile fish, while healthy coral colonies attract new recruits. | A new study has shown that reefs overgrown with algae or characterized by coral rubble send chemical cues that repel juvenile fish, while healthy coral colonies attract new recruits. | ||
===Overview and Definition=== | |||
Nutrient loading is the influx of nutrients into the water surrounding reefs that negatively affects the overall health of the reefs | |||
===The Importance of Nutrients=== | |||
Essential Plant Nutrients are carbon, hydrogen, and oxygen. | |||
===The Effects=== | |||
Indirect effects include adjustments to cycles of carbon, hydrogen, and oxygen. These adjustments affect the biosphere and in turn limit tourist interaction. In most Caribbean communities, the tourist industry is the main industry. When nutrient loading occurs, tourist levels decrease and detrimental effects are incurred with the local economy. | |||
Nutrient | |||
Direct effects include algae build up, degradation of reefs, relocating of fish life, nutrient cycling adjustments. Algae build up leads to limited sunlight and increased calcification. Increased calcification leads to the degradation of reefs and in turn the relocating of fish life. The influx of nutrients (nutrient loading) also adjusts nutrient cycling and how coral reefs filter and adjust to the nutrients themselves. Light reduction is a direct effect of nutrient loading as the availability of light decreases directly as a function of particle concentration and water depth. Increased nutrient runoff into semi-enclosed seas accelerates phytoplankton production to the point that it increases turbidity and reduces light penetration. | |||
===Too Many Nutrients/Not Enough Nutrients=== | |||
Level of nutrients must be perfect, not too many, and not too less. | |||
===Nutrient Loading in the Bigger Picture=== | |||
Land based pollution sources are the primary cause of reef degradation and in the Caribbean, 80% of ocean pollutions originates from land development. Run-off carries large quantities of sediment from land-clearing, high levels of nutrients from agricultural areas and sewage outflows, and pollutants such as petroleum products and pesticides. Furthermore, excess nutrients leads to poor water quality and poor water quality causes decreased oxygen and increased nutrients in water (eutrophication). | |||
Eutrophication leads to algae growth on reefs, crowding out corals, significantly degrading ecosystems, pesticides interfering with coral reproduction and growth, and pathogens that can be introduced to coral reef systems. Two examples of this are aspergillus sydowii, a disease in sea fans, and serratia marcescens, a disease linked to white pox. | |||
Sources: | Sources: | ||
Revision as of 16:05, 15 April 2015
Nutrient Loading
Coral reefs thrive in nutrient poor water. Excess nutrients from runoff, wastewater treatment plants, coastal development, marinas, etc. can encourage the growth of fast-growing macroalgae, which can smother a reef.
A new study has shown that reefs overgrown with algae or characterized by coral rubble send chemical cues that repel juvenile fish, while healthy coral colonies attract new recruits.
Overview and Definition
Nutrient loading is the influx of nutrients into the water surrounding reefs that negatively affects the overall health of the reefs
The Importance of Nutrients
Essential Plant Nutrients are carbon, hydrogen, and oxygen.
The Effects
Indirect effects include adjustments to cycles of carbon, hydrogen, and oxygen. These adjustments affect the biosphere and in turn limit tourist interaction. In most Caribbean communities, the tourist industry is the main industry. When nutrient loading occurs, tourist levels decrease and detrimental effects are incurred with the local economy.
Direct effects include algae build up, degradation of reefs, relocating of fish life, nutrient cycling adjustments. Algae build up leads to limited sunlight and increased calcification. Increased calcification leads to the degradation of reefs and in turn the relocating of fish life. The influx of nutrients (nutrient loading) also adjusts nutrient cycling and how coral reefs filter and adjust to the nutrients themselves. Light reduction is a direct effect of nutrient loading as the availability of light decreases directly as a function of particle concentration and water depth. Increased nutrient runoff into semi-enclosed seas accelerates phytoplankton production to the point that it increases turbidity and reduces light penetration.
Too Many Nutrients/Not Enough Nutrients
Level of nutrients must be perfect, not too many, and not too less.
Nutrient Loading in the Bigger Picture
Land based pollution sources are the primary cause of reef degradation and in the Caribbean, 80% of ocean pollutions originates from land development. Run-off carries large quantities of sediment from land-clearing, high levels of nutrients from agricultural areas and sewage outflows, and pollutants such as petroleum products and pesticides. Furthermore, excess nutrients leads to poor water quality and poor water quality causes decreased oxygen and increased nutrients in water (eutrophication).
Eutrophication leads to algae growth on reefs, crowding out corals, significantly degrading ecosystems, pesticides interfering with coral reproduction and growth, and pathogens that can be introduced to coral reef systems. Two examples of this are aspergillus sydowii, a disease in sea fans, and serratia marcescens, a disease linked to white pox.
Sources: http://www.ncbi.nlm.nih.gov/pubmed/11381890 / http://www.dnr.state.md.us/coastalbays/water_quality/nutrient_load.html / http://www.sciencedirect.com/science/article/pii/S1877343513001917 / http://reefkeeping.com/issues/2006-08/cj/index.php / http://www.fisherycrisis.com/coral3.html / http://oregonstate.edu/ua/ncs/archives/2013/nov/large-study-shows-pollution-impact-coral-reefs-%E2%80%93-and-offers-solution / http://www.windward.hawaii.edu/facstaff/miliefsky-M/BIOL%20171L/Lab%200%20Intro/review02.pdf
Dixson, Danielle L., David Abrego, and Mark E. Hay. Chemically mediated behavior of recruiting corals and fishes: A tipping point that may limit reef recovery. Science 22 August 2014: Vol. 345 no. 6199 pp. 892-897. DOI: 10.1126/science.1255057