Cultural Eutrophication

Phytoplankton are microscopic photosynthesising organisms which live in water. In favourable environmental conditions they have a very high rate of reproduction. They are eaten by microscopic animals called zooplankton. In an investigation, samples of water were removed from a lake at intervals over a twelve-month period and the biomasses of these organisms were determined. The results are shown in the graph.

The Effects of Nitrogen and Phosphorus Enrichment on Water Samples from Encanto Lake and the Rio Salado River.

Even though, fertilizers are needed to supply essential nutrients to the growth of plants; an excess of them is one of the major issues contributing to pollution in the Chesapeake Bay Watershed. Fertilizers are mainly composed of two elements: nitrogen and phosphorus.(4) Throughout the years, millions of pounds of this nutrients are applied all around the Chesapeake Bay Watershed; everything not absorbed by the soil or taken up by plants eventually reaches the Chesapeake Bay through storm-water runoff. This nutrients end up creating algae blooms in the water, which reduce the amount of sunlight available to underwater grasses; not allowing plants to photosynthesize and produce the food they need to survive. Algae then decomposes creating dead zones killing fish and other species since oxygen is needed for any organism to live. (5)

Human activities add nutrients such as nitrogen and phosphorus, which cause imbalances in the Everglade water chemistry, disrupting plant communities and altering wildlife

Phosphorus, “...the primary algae-feeding nutrient in Lake Erie, and contributed to the largest algae bloom in history last year” (McCarty, para. 3), is a key factor in how

Did you ever wonder how things you do everyday effect the Chesapeake Bay watershed and Its tributaries? Well, It turns out to be not so good. One of the main causes for the Bay’s bad health are nutrients which are caused by excess nitrogen and phosphorus in the air and water. Plants and animals need nutrients to survive but when too many nutrients are in the water they fuel the growth of algae blooms and create conditions that are harmful for aquatic creatures.

Data analysis of long term trends and seasonal trends in Phosphorus at the Bosherston Lakes, South West, Wales.

Spanning lengths over 300,000 meters, this it is a watershed that extends over six states, the District of Columbia, and meets the needs of over 15 million individuals. With its high rate of productivity, its economic and social importance to the surrounding areas, and its close proximity to the U.S. capital, the Chesapeake has the recipient of significant attention for quite some time(Boesch, Donald). One of the issues that threatens this important estuary is eutrophication. For the majority of the 20th century, research, guidelines, and management activity were focused on other issues like wetland loss, over harvesting of fisheries, infectious wastes, etc (Davidson et al, 1997). It took until the final quarter of the century for widespread realization to hit that eutrophication had deteriorated the Bay, with extreme consequences for the Bay’s resources(Malone et al., 1993). After awareness of the impact of eutrophication on water bodies began to increase, when it came to making policies and managing the Chesapeake Bay, eutrophication reduction took precedence over any other issues. As the Bay remains a very important body of water, the significance of understanding one of the major processes responsible for its degradation remains as well. This paper aims to understand the contributing factors of eutrophication in the Chesapeake Bay, with a special focus on the effects of air and

A comprehensive investigation on how nutrients in waterways were increasing, was undertaken by a body of individual scientists and their findings were as follows;

Eutrophication is when there is too much nutrients in the water, as stated above. Eutrophication can come from farmers fertilizing their fields and some detergents. We tested for phosphates, salts or ester of phosphatidic acid. We also tested for nitrates, salts or ester of nitric acid. The more the phosphates and nitrates, the more eutrophication is present in the stream. We tested for dissolved oxygen, the amount of oxygen in the water, as well. We found found a very low level of phosphates with an average of 0.1 parts per million (ppm). We also found a very low level of nitrates with an average of 0.9 ppm. The dissolved oxygen level was 9.8 ppm. The higher the velocity of the water, the more dissolved oxygen it will contain. All of these measurements are very good and show that there is little or no eutrophication in the

Our end results only supported to some extent our hypothesis that increasing numbers of brine shrimp would directly cause decreases in algae concentration. Our hypothesis, if applied to only the jars of 3 and 6 brine shrimp, would be highly supported, due to the significant difference in algae concentrations. Evidently, the more shrimp that were present in the ecosystem, the less algae that were available at the end. In an ecosystem with more consumers, the consumers demand a higher amount of nutrients from the environment, or more specifically, the producers. And as the consumers develop and grow, those demands also grow. And thus, when we increased the amount of brine shrimp, more algae were consumed per unit time. Though the rate of consumption from the brine shrimp did not exceed the rate of growth of the algae in any jar, the

Most people eat only what they need, however others eat all the available food until they can’t move. Small aquatic animals and plants behave in the latter fashion and eat until they run out of food. When the supply of food keeps coming, the small plants and animals keep eating and growing and eventually one dominant form will take over, changing the waterway, sometimes permanently. This situation, called eutrophication, exists in Little Narragansett Bay (LNB) with the Seaweed Cladophora and the nutrient nitrogen. Nitrogen normally restricts growth by being scarce in marine waters (Nixon, 2009). If we bring LNB back into balance by reducing nitrogen, we may be able to undo some of the damage, allow seagrass to regrow and return the associated

Back to the history, the eutrophication problem was first time concerned by public on Great lakes at the 1960s, the Lake Erie was covered by algae as a result of over dumped phosphorus from the sewage and other waste water, at that time, the Lake Erie was known as the “Dead Sea of North America”(Fitzpatrick, J. J., and Di Toro 1999). The reason cause this problem can be concluded in 2 points, 1. the stresses of overfishing, 2. development of phosphorus-based detergents. At the end of 1960, the Canada and the United States have realized the penetrance of this problem and finally sit on the table to sign an agreement that limiting phosphorus dumps to the Lake Erie, and plan to control existing unstoppable algal growth. Because of the awareness of Canada and US government, the concentration of phosphorus got a significant success. And this problem happened again during the 1990s, but this time the reason why this happen is more complexly.

In this paper I will examine multiple perspectives in an attempt to understand the recent eutrophication of the Chesapeake Bay. Our textbook, Cambell Biology defines eutrophication as a process in which nutrients, usually phosphorus and nitrogen, are unusually present in a body of water, leading to algae blooms and accelerated growth. Anoxia is a condition in which areas of water are severely depleted of dissolved oxygen.

The purpose of this experiment is to understand the effects of nutrient enrichment and eutrophication, using samples of water from Rio Salado and Encanto Park. The samples will contain different concentration levels of nitrogen, phosphorous and nitrogen and phosphorous combined and the impact it has on algae growth. The results recorded showed that the nitrogen concentration levels had a little change, phosphorous levels had a higher change and phosphorous and nitrogen combined had a significantly higher change, resulting in higher algae growth. The results showed that phosphorous indeed is a limiting nutrient in algae growth, but to achieve the highest growth rate, both nitrogen and phosphorous need to be combined.