Climate
There are numerous factors that impact climate change in estuaries. These are sea level rise, increased sea surface and air temperature, changes in precipitation and storm intensity and ocean acidification.
Higher temperatures are expected to raise the sea level because of the expanding ocean water, melting mountain glaciers, small ice caps, and the causing portions of the coastal section of the Greenland and Antarctic ice sheets to melt or slide into the ocean. Snowfall over Antarctica and Greenland are a cause of higher temperatures.
Certain greenhouse gas concentration can have a huge impact on climate change in estuaries. Since it is already projected that throughout this year there will be a continued increase in average global temperatures; it is uncertain how quickly the Earth’s temperature will increase because of the future greenhouse gases and aerosol emissions. Temperatures in the future for estuaries in the Maritimes may not only change because of human activities, but also because of climate ‘feedbacks.’ Positive feedback is one that can arise from the melting ice. The result of losing ice would be additional warming and this could happen since the seawater is not reflective where as the ice is. Negative feedback occurs when there is an increase in low clouds from increased evaporation, which is a result of warming. The only way to decrease the warming would be with the addition of thick clouds involving the reflection of sunlight.
Major Animal Life
Common animal life includes sea birds, fish, crabs, lobsters, clams, and different types of shellfish, raccoons, opossums, skunks and numerous reptiles. Microorganisms include fungi, bacteria and protozoa of which viruses are not accounted for. Shellfish such as mussels, clams, snails, limpets and Native Oysters exist in the estuaries located in Canada’s East Coast. Segmented worms can be defined as those organized of whose bodies are divided into sections. In addition to segmented worms, one may find ribbon worms, flatworms and bristle worms. Ribbon worms are those that have a threadlike or ribbon like forms. Flatworms can be defined as having a soft-body with the lack of body cavity and respiratory organs, which would then restrict them to flattened shapes that would only allow oxygen and small amounts of nutrients to pass through their bodies in order for them to live. Bristle worms are composed of many segments, similar to segmented worms except have bristles along its body in entire length. Shrimp, crabs, copepods and amphipods are various types of crustaceans that may exist in the estuaries located in the Maritimes. Numerous fishes exist of which some are Pacific Salmon, herring, Cutthroat Trout, stickleback and scuplins. Birds such as eagles, Canada Geese, Great Blue Herons, plovers, Black Oystercatchers, killdeers, sandpipers, mergansers, kingfishers, widgeons and mallards all exist in Canadian estuaries in Maritimes. Young fish can quickly grow healthy because of the salt water.
Major Plant Life
Eelgrass and sedges are two of a few aquatic plants that live in estuaries. Dune grass and salt grass are other terrestrial plants that one may find in such locations. The nutrient-rich waters of estuaries and other wetlands that may flow in or connect to a few estuaries cause a highly healthy environment for the plants. The high constant increase in nutrient concentration provides support for plant life such as phytoplankton, sea grasses, macro algae, and emergent grasses. Phytoplankton can be defined as microscopic plant organisms that live in the ocean including wetlands. There are many different types of species, each having its own shape and form. Phytoplankton grows in enormous amounts around the world and can be known as the foundation of the marine food chain. Sea grasses are flowering plants that grown underwater and are known to produce oxygen similar to land plants. Microalgae basically refers to those algae that are visible to the naked eye as opposed to Microalgae. Emergent grasses that are located in some of the Estuaries in Maritimes can be described as those that grow in water and live in it, but of which some is also above the surface of the water.
Below is a food web of an Estuary involving Plants and Animals:
Human Activities
Urban and agricultural developments are main threats to estuaries located in the Maritimes. For thousands of years, the action of practicing agriculture on rich soils of estuaries has been practiced which have had little negative impacts. The recent years have nevertheless proven that methods of agriculture such as damming and filling-in estuaries would have a huge severe impact on the ecological occupation of the wetland. Estuaries located in large cities have been used and torn to such a degree that restoration with great expenses would be a practical solution. The excess sediment and erosion is caused by actions of logging and construction. This can affect the estuaries because of the resulting poor water quality, chemical pollution and excess nutrients. Fertilizers can cause the increase in nutrients, and a lot of sediment leftover would overwhelm producers such as eelgrass and even animals. The resulting condition of the impermeable water surface would act as a barrier for the water reaching the soil and would also transport oils from nearby roads into estuaries. It is very common for estuaries to be polluted because of its location between the land and the sea. Bioconcentration and bioaccumulation are processes of how organisms accumulate compounds of pollution and increased concentrations.
Factors Affecting the Environmental Health
For decades, the features of estuaries attract humans from all over the world. Their semi-enclosed nature between the land and the sea with the included initial high productivity would be the cause. However, the increase in population growth in coastal regions would also mean the increase in pollution due to construction and logging. When inorganic substances and metals that are known as toxicants exert into the estuaries, the Bioconcentration in these materials is passed in the food web resulting in sever impacts in the higher trophic level species. This in turn would cause illness and death to the humans because of the consumption of the organisms. Although it may be an attraction, there are threats such as natural disasters; hurricanes, storm erosion and tsunamis can be of them. Fishing can cause low oxygen conditions in estuaries. For example, the harvesting of oysters could eliminate oyster reefs. The organic matter that would be initially filtered by oysters would fall to the bottom and it originally could be done over several days, and is then consumed by benthic microbes.
Bibliography
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