Eutrophication
On
River Ecosystem
Eutrophication Excessive richness of nutrients in a lake or other body of water, frequently due to run-off from the land, which causes a dense growth of plant life. Eutrophication arises from the oversupply of nutrients, which induces explosive growth of plants and algae which, when such organisms die, they consume the oxygen in the body of water, thereby creating the state of hypoxia (deficiency in the amount of oxygen reaching the tissues)
Mechanism of Eutrophication
When algae die, they decompose and the nutrients contained in that organic matter are converted into inorganic form by microorganisms. This decomposition process consumes oxygen, which reduces the concentration of dissolved oxygen. The depleted oxygen levels in turn may lead to fish kills and a range of other effects reducing biodiversity. Nutrients may become concentrated in an anoxic zone and may only be made available again during autumn turn-over or in conditions of turbulent flow.
Enhanced growth of aquatic vegetation or phytoplankton and algal blooms
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Species diversity decreases and the dominant biota changes
2. Plant and animal biomass increase
3. Turbidity increases
4. Rate of sedimentation increases, shortening the lifespan of the lake
5. Anoxic conditions may develop
Ecological Effects
Many ecological effects can arise from stimulating primary production, but there are three particularly troubling ecological impacts: decreased biodiversity, changes in species composition and dominance, and toxicity effects.
• Increased biomass of phytoplankton
• Toxic or inedible phytoplankton species
• Increases in blooms of gelatinous zooplankton
• Increased biomass of benthic and epiphytic algae
• Changes in macrophyte species composition and biomass
• Decreases in water transparency (increased turbidity)
• Colour, smell, and water treatment problems
• Dissolved oxygen
Nitrogen and nitrates relate to Hypoxia via the process of eutrophication. Since Nitrogen is a limiting nutrient in most waters, the added input of nitrate causes massive growth in algae. The algae rapidly consume all available N, and once the nutrient is limited again, the alga dies en masse. As the alga decomposes, oxygen is depleted in the water. This lowers dangerously lowers the level of dissolved oxygen in the water, which harms living organisms in the area. Small organisms and organisms that are immobile or unable to escape low-oxygen areas are particularly vulnerable. Hypoxia and resulting “dead zones” are harmful to local fishing and shrimping industries and algal blooms hurt the tourism industry. Hypoxia has lead to a decrease of about 25% in the brown shrimp habitat, forcing shrimping operations further offshore. As the hypoxia issue continues to grow, negative human effects will only increase. Since nitrate runoff from ag. has been proven to be the dominant source of hypoxia, policies could be enacted to effectively deal with “point-source” pollution. This makes enacting environmental policy more easily adapted, possibly included in past policy such as the Clean Water Act.
Timmons, J. B., Alldredge, B., Rogers, W. E., & Cathey, J. C. (2012). Feral hogs negatively affect native plant communities. Informally published manuscript, Texas AgriLife Extension Service, Texas A&M , College Station, TX, Retrieved from http://feralhogs.tamu.edu/files/2010/04/feral-hogs-native-plants.pdf
The Chesapeake Bay is the nation’s largest estuary with six major tributaries, the James, the Potomac, the Susquehanna, the Patuxent, the York, and the Rappahannock Rivers, feeding into the bay from various locations in Maryland, Virginia, Pennsylvania, and the District of Columbia (Chemical Contaminants in the Chesapeake Bay – Workshop Discussion 1). These areas depend on the Bay as both an environmental and an economic resource. Throughout the last 15 years the Chesapeake Bay has suffered from elevated levels of pollution. Nitrogen and phosphorous from wastewater treatment plants, farmland, air pollution, and development all lead to reduced water clarity and lowered oxygen levels, which harm fish, crabs, oysters and underwater grasses (Key Commission Issues 1). There are other types of pollution in the bay such as toxic chemicals, but because nutrient pollution is the most significant and most widespread in the Bay its effects are the most harmful to fisheries. Nitrogen and phosphorous fuel algal blooms which cloud the water and block sunlight from reaching underwater grass beds that provide food and habitat for waterfowl, juvenile fish, blue crabs, and other species (Blankenship 11-12). Algae plays a vital role in the food chain by providing food for small fish and oysters. However, when there is an overabundance of algae it dies, sinks to the bottom of the Bay, and decomposes in such a manner that depletes the oxygen levels of the Bay (11). The reduced oxygen levels in the Bay reduce the carrying capacity of the environment and these “dead areas” sometimes kill off species that can not migrate to other areas of the Bay, such as oysters (11). Increased abundance of algal blooms also led to the overabundance of harmful and toxic algae species and microbes such as the microbe Pfiesteria, which was responsible in 1997 for eating fish alive and making dozens of people sick (12). The heightened awareness of diseases that can be contracted through consumption of contaminated fish also has an economic impact. Therefore, the excess levels of nitrogen and phosphorous have fueled an overabundance of algal blooms, which has reduced water clarity and lowered oxygen levels, affecting many species within the bay and ultimately the industries that rely on these species.
Eutrophication is a concern in the Chesapeake Bay. Eutrophication is caused by excessive amounts of nutrients. Excessive nutrients in the bay have negative affects on the bay's ecosystem. The extra nutrients make the environment unbalanced. The extra nutrients cause a chain reaction that depletes oxygen and kills most of the organisms in that area. This is what is known as a dead zone.
Because of farm fertilizer, an excess quantity of nitrogen and phosphorus can be wash down becoming runoff into rivers. From this, marine algal blooms cause the water to turn green from the chlorophyll (Reed, 2011). Eutrophication then becomes a dilemma in the system causing either an increase of primary production or an expansion of algae. An enormous expansion of phytoplankton on the water’s surface is then established. At the same time the water column is also stratified, meaning things such as the temperature and salinity are not sync from top to bottom. The seasonal warm surface water has a low density forming a saltier layer above while the cooler and more dense water masses near the bottom layer is isolated from the top cutting off oxygen supply from the atmosphere (Overview, 2008).
Eutrophication is a concern in the Chesapeake Bay. Eutrophication is caused by excessive amounts of nutrients. Excessive nutrients in the bay have negative effects on the bay's ecosystem. The extra nutrients make the environment unbalanced. The extra nutrients cause a chain reaction that eventually kills most of the organisms in that area. This is what is known as a dead zone.
The 'Secondary' of the 'Secondary' of the 'Secondary' of the 'Secondary' of the 'Secondary' of the 'Secondary' of the 'Secondary' of the 'Secondary' of the 'Secondary' of the 'Secondary' of the Wildland Fire on Ecosystems: Effects of Fire on Soil and Water. Published by the United States Department of Agriculture, Forest Service. Retrieved on line July 7, 2005.
Destroying the habitat of different plants and animals, they no longer have a place to live. Their food source and nutrients are taken away and have nowhere else to go. These organisms will die out and there will be a loss in the diversity of that ecosystem. That ecosystem can then start to crumble as the habitats are taken away and the plants and animals have no home. With no habitat in which the organisms can live in, there is going to be very little diversity.
Our oceans take a large beating every day by the extremely large amount of pollution humans produce. Our society easily dumps their waste into the oceans to dispose of the excessive amount of garbage, sewage, and chemicals, but this small and simple solution is creating an even bigger problem. The way humans dispose of their wastes is causing the death of our beloved marine life. Not only are we killing off our animals, our food source, and our resources, we are also minimizing our usable water. By having a better understanding of the problem on the severe dumping, it will be easier to find ways to help minimize the pollution that is going into the ocean.
Technology has facilitated the transportation of a mass of people from one part of the world to another. This massive human travel, either it be the exploration, colonization, or trade of the early European nations or the contemporary infrastructure of trade, tourism, or globalization, has impacted the environment and the humans involved. This paper focuses on the era of European expansion to examine the effect of human travel on the environment and humans. The Europeans were not only responsible for the actual exploitation of natural resources in the places they discovered, but they also took diseases, new technologies, and non-native plant and animal species which had a tremendous impact on the native human population as well as the environment.
Microbial decomposition releases nutrients into the environment that are needed by other organisms. Microbes are also involved in the cycling of many other important compounds in — and between — ecosystems, including oxygen, carbon and nitrogen. Many microbes use the energy of sunlight to convert carbon dioxide to oxygen, which we need to breathe. As they do this, they create new organic material — themselves — which are then eaten by other organisms. In this way, the cycling of nutrients and energy
Agriculture is the major farming activity. Agriculture's scale means not only that large area is directly affected, but that local and even regional climates can be affected. The draining of water from rivers and watersheds for irrigation leads to drier natural habitats. Those rivers that receive runoff from farmland are often poisoned by excessive nutrients and pesticides.
Research from the University of California San Diego Scripps Institution of Oceanography said that species in the ocean consume a projected 12,000 to 24,000 tons of plastic every year in the Pacific Ocean (Nall, 2014). Pollution of recyclable materials in the oceans is one of the leading causes of why some marine species are nearing extinction. Many authors of articles and books analyzing this topic tend to agree that pollution of our oceans is a problem. The future of this problem is where their ideas tend to differ. The following four literature reviews attempt to demonstrate and support my belief that pollution is getting worse in the ocean and more marine life ecosystems are being affected, but there are things that we as humans can do to change this. Imagine a world where we didn’t have to constantly worry about the vicious cycle of humans affecting animals and then animals in turn affecting us through consumption.
If many dangerous chemicals are released into the atmosphere, the chemicals dissolve the ozone layer and this causes ultraviolet radiation to directly hit the earth. Figure 2 below gives an overview of the ozone layer. Figure 2: Ozone Layer. Source: Tasos Gkionakis (2017). Eutrophication Eutrophication is a condition where high amounts of nitrogen is present in some pollutants gets developed on the sea surface and turns it into algae and this affects the fish and animal species.
What is pollution? Pollution is a detrimental enemy to all species that walk on earth. It is a product of mankind carbon foot print on the environment. It consists of chemicals or particles in the air that can harm the health of humans, animals, and plants. Pollution occurs when pollutants contaminate the natural surrounding; which brings about changes that affect our normal lifestyles adversely. Pollutants are the key elements of pollution which are generally waste materials of dissimilar forms. Pollution disturbs our ecosystem and the balance in the environment. With innovation and development in our lives pollution has reached its peaks; giving rise to global warming and human illness. When raw materials, water, energy and other resources