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 WHAT IS A COASTAL ZONE?

 Source: visitmaui.com
For all the vast miles of open waves, for all the leagues of deep, dark water, for all the huge openness and mystery  some of the open ocean, some of the most important waters are those within several hundred miles of the coasts.

A coastal zone is often described as the coastal ocean and the land adjacent to it. It covers approximately 7% (26x106 26x10^6 km²) of the surface of the interface between land and ocean. Despite its relatively modest surface area, a  the coastal zone is one of the most geochemically and biologically active areas in the biosphere.  For example, it accounts for at least 15% of oceanic primary production; 80% of organic matter burial; 90% of sedimentary mineralization; and 50% of the deposition of calcium carbonate. It also represents provides 90% of the world fish catch and its overall economic its economic value has been recently estimated as estimated to comprise at least 40 % 40% of the total economic value of the world's ecosystem services and natural capital. Additionally, coastal areas contain high proportion of the faunal and floristic biodiversitycontain large amounts of biodiversity. However, this region is changing rapidly as a consequence of human influenceunder human influences; about 40% of the world's population lives within 100 km of the coastline. As a result, our goal is to create solutions that would mitigate the effects of these negative influences on coastal habitats and wild fish stocks. (Gattuso et al. 2007)

In this section, we will treat the coastal zone primarily as the freshwater bodies that drain to the sea, the land area influencing those water - bodies, and the  water within and waters on the continental shelf of a landform, especially estuarine waters (waters where salt and freshwater mix).

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The water on earth is a constantly changing, dynamic system; it flows, evaporates, condensatescondenses, is stored, and is absorbed. Events in one waterway later affect downstream waters and the ocean. The impacts of coastal zones on marine ecosystems and fisheries is fisheries are profound, not only because of the incredibly incredible biodiversity and biomass in coastal waters, but also because of the various ecosystem functions that coastal areas provideperform. Coastal and estuarine areas are often critical spawning and recruitment grounds; damages to the ecosystem and to fisheries there can have wide-ranging effects on the population elsewhere. Furthermore, many fish migrate upstream into freshwaters fresh waters to spawn (anadromous fish, like shad) or live in freshwater and spawn in the ocean (catadromous fish, like eels); changes in water quality or physical habitat can destroy these populations by decimating their reproductive capacityability to reproduce. The connections between freshwater, estuarine, and marine areas are many and are not yet fully understood. However, we do know that in order for creatures to survive, they require --on the most basic level-- food, water, and a place to live. An organism's habitat encompasses these concepts. It is the foundation for a healthy ecology. must include all of these things.  Without an environment in which its basic needs can be fulfilled, an organism cannot survive. As such, our group proposes to maximize habitat and water quality in these areas so as to minimize fishery fish mortality from environmental factors.

Specifically, there There are several classes of problems that affect habitat quality and fisheries. They include:

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(3)    ObstructionObstructions to migration \[Link to Child page 4\]

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The most easily identifiable form of environmental contamination is point source pollution. Point source pollution occurs when contaminants are introduced to an ecosystem at a singular specific location and point in time. Common examples include:

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-         Waste-water disposal !stormflow.jpg|width=651,height=434!Source: USGS

 
The effects of these various materials in aquatic ecosystems vary with respect to vary depending on the chemical or contaminant involved and with respect to the and the amount of the discharge; the regulation of discharges into water is an important aspect of the preservation of overall water quality.

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Non-point source pollution arises when contaminants are carried into waterways by natural processes, like run-off runoff or air currents. A common example is when run-off runoff carries fertilizers from farms into waterways. Harder to pin-point pinpoint - because the source covers a large land area - and more difficult to regulate than point - source pollution, especially because of the lack of explicit fault by any one personof a single responsible party, non-point source pollution is a serious but serious and insidious threat to ecosystem health. Examples of major contaminants include:

Source: USGS and Barbara Hite

 
-         Suspended sediment

Sediments occur naturally and are integral components of aquatic systems. Nearly all waters contain suspended sediments that may be of physical, chemical or biological origin, and the quantities of these sediments usually vary with season. This natural variation in suspended sediment concentrations occurs typically in response to natural events (i.e. rainfall and snow melting) which increase the flow and sediment levels of the waterways. As a result, in order to ensure the ensure their survival of their species, aquatic organisms aquatic species have adapted their life cycle cycles to accommodate these natural variations in their the environment (Birtwell 1999). However, the input of suspended sediment from catastrophic events such as floods and volcanic eruptions, and anthropogenic activities such as dredging, mining, and spilling releasing water from dams, are recognized as a potential threat threats to the well-being of marine biota.

Although sediment, and its associated effects on water clarity and turbidity, is an inherent component a natural component of aquatic systems, it is apparent from scientificresearch scientific research that there is an increased risk to the survival of aquatic organisms when sediment levels exceed background values for a particular period of time. There are many ways which an excessive amount of sediment might be harmful to a fishery. These are byThese include:

A)     Acting directly on the fish swimming in the water in which solids are suspended, and either  either by killing them or reducing their growth rate, resistance to disease, etc. For example, increased   Increased turbidity and decrease decreased light penetration alters alter fish feeding and schooling practices, which can lead to reduced survival. The high concentrations of sediments also irritate the gills of fish , and can cause death.  In addition, they destroy  sediment can destroy the protective mucous covering the eyes and scales of fish which makes , making them more susceptible to infections.

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C)      Modifying natural ecosystems of the aquatic organisms. For example, high .  High concentrations of sediments can dislodge plants, invertebrates, and insects in the delta bed. This directly affects the food source of fish, and can result in smaller and fewer fish.

D)     Carrying toxic agricultural and industrial compounds. If these toxins remain in the areas they compounds, which can cause abnormalities or death in the fishin fish. (Environment Canada 2001) In order to facilitate the protection of aquatic organisms from elevated levels of sediment in their environment, guidelines and criteria have been formulated. Dating back to 1964 As early as 1964, the European Inland Fisheries Advisory Commission (EIFAC) was one of the first to put  put forth such guidelines for the protection of fisheries fishery resources, which are as follows: 

<25 ppm* of suspended solids - no evidence of harmful effects onfish and fisheries;
25 - 80 ppm - it should be possible to maintain good to moderate fisheries, however the yield would be somewhat diminished relative to waters with <25 ppm suspended solids;
80 - 400 ppm - these waters are unlikely to support good freshwater fisheries ; and
400 ppm - suspended solids - at best, only poor fisheries are likely to be found. *

• Parts per million approximate (mg- L--1 ) Numerous criteria and guidelines have been formulated since then, and more recent ones have been based on the analyses of Newcombe and MacDonald (1991), Anderson et al. (1996), and Newcombe and Jensen (1996) and Caux et al. (1997). These authors state that aquatic biota respond to both concentration of suspended sediments and the duration of exposure to them, and relate the two through an "index of pollution intensity" or "stress index" (Birtwell 1999). Newcombe and

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• MacDonald's 1991 paper recommended the use of a "stress index" that is "calculated by taking the natural logarithm of the product of concentration and duration"  and would provide resource managers with a method to predict the effects of pollution

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• episodes on aquatic biota. The British Columbia Ministry of Environment, Lands, and Parks (BCMELP) (1998), and the Canadian Council of Ministers of the Environment (CCME) (1999) guidelines are the most recent documents on this topic, and they are based, in part, on the publication by Caux et al. (1997).            

It is recognized that there is some level of risk to aquatic organisms depending on the sediment levels discharged and the sensitivity of the organisms in the receiving stream. However, scientists have concluded that these impacts would be best assessed using the concentration of suspended sediment above background levels. The levels of risk and the corresponding concentrations of sediment follow:

Source: Birtwell 1999

It is concluded that elevated levels of sediment (typically over background) may be harmful to fish (i.e. acutely lethal, or elicit sublethal responses that compromise their well-being and jeopardize survival), and in addition, negatively impact their habitat. Criteria, guidelines and recommendations, though having been formulated though formulated by many different government agencies, all tend  tend to be mutually supportive. At the same time they have application limitations, especially relating to the protection of aquatic organisms from the effects of sediment concentrations £ concentrations of tens of mg- L-1. Application of the criteria must be done while recognizing potential impacts on aquatic organisms at both the lethal and the sublethal level. Particle size and nature of the sediment must be considered as well (Birtwell 1999).

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Nutrients are required by aquatic ecosystems for primary production; plants, often algae, absorb these nutrients and use them to grow. These plants form the base of the food chain in aquatic ecosystems. However, excess nutrients, especially nitrogenous compounds, are carried by runoff from agricultural areas and cause a phenomenon called eutrophication. The nutrients over-fertilize the ecosystem and cause an explosion in  algae in algae population--an algal bloom. When this huge mass of algae dies, however, it consumes oxygen in its decomposition, lowering the dissolved oxygen content for the waterway in general. Eutrophication has been a major problem in estuarine areas, like the Chesapeake Bay in Maryland, USA and continues to be a problem in freshwater lakes and ponds as well.

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Trace metals are required for aquatic life but in higher concentrations heavy metals , such as iron, lead, mercury, aluminum, and magnesium are toxic to fish, especially at low pHs (PA FBC). One reason metal toxicity is such a problem is that no natural processes exist to neutralize or remove them (Chapman, 1996). Metals also tend to accumulate in bottom sediments (Chapman, 1996), which presents a problem if those sediments are later disturbed. Industrial wastewater discharges (point - source) and mining are common metal sources, although metals like lead (from automobiles) can also come from atmospheric deposition. AlAluminum, Cdcadmium, Crchromium, Cucopper, Feiron, Hgmercury, Mnmanganese, Ninickel, Pblead, Znzinc, Asarsenic, and Se and selenium are the commonly monitored "metals" although Beberyllium, Tlthallium, Vvanadium, Sbantimony, Mo and molybdenum are also important if it is believed they will occur in an area (Chapman,1996).

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Coral Reefs !GrecianRocks.1965.jpg|width=547,height=358!A star coral. Source: USGS 

Coral reefs are unique and beautiful ecosystems. They have the most species per unit area of any marine environment and hold perhaps 1-8 million as of yet undiscovered species (Reaka-Kudla, 1997). These species hold great promise for new pharmaceuticals (NOAA) and also provide goods and services worth $375 billion per year, despite their only covering under 1% of the Earth's surface (Costanza et al, 1997). Developing countries rely on coral reefs for approximately ¼ of total fish catch (Jameson et al, 1995). Coral reefs offer benefits to people living in coastal areas by acting as buffers to wave action; they may also protect coastal wetlands (NOAA).

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Mangrove Swamps !ellen1.jpg!Source: USGS 

According to the U.S. Environmental Protection Agency, mangroves are coastal wetlands found in tropical and subtropical regions (2006). Mangroves are characterized by trees or shrubs that have the common trait of growing in shallow and muddy salt water or brackish waters, especially along quiet shorelines and in estuaries. These halophytic trees are able to thrive in salt water conditions because of specialized rooting structures (such as prop roots and pneumatophores), specialized reproduction (vivipary or live birth) and the ability to exclude or excrete salt (Lee County Government).  In North America, mangroves are found from the southern tip of Florida along the Gulf Coast to Texas. The importance of mangroves has been well established. They support a wide diversity of animals and vegetation since these estuarine swamps are constantly replenished with nutrients transported by fresh water runoff from the land and flushed by the ebb and flow of the tides (U.S. EPA 2006). They also play a pivotal role in the life cycles of aquatic organisms. For example, they function as nurseries for a variety of marine biota, For example, seventy-five percent of the game fish and ninety percent of the commercial species in south Florida depend on mangrove ecosystems (Law et al.). In addition, these coastal wetlands are valued for their protection and stabilization of low-lying coastal lands from storm winds, waves, and floods. The amount of protection afforded by mangroves depends upon the width of the forest (Lee County Government). Although mangroves are increasingly threatened by anthropogenic activities (such as the damming and mangrove conversions), efforts are underway to enhance the protection of these threatened and valuable ecosystems (U.S. EPA 2006).

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(5) Invasive Species !1354035_lg.jpg|width=194,height=176!A seemingly innocuous invader, the zebra mussel, has devastated fisheries and industries in its host lands. Source: USGS !db_snakehead0031.jpg!The invasive snakehead. Source: USGS, Artist: Susan Trammell 
 

Invasive species are non-native species that have been introduced to a water-way and that have been able to establish themselves in that ecosystem at the expense of other species. Increase in invasive species is correlated with a decrease in overall biodiversity and loss of ecosystem services and is a major concern in coastal ecosystems (Worm et al, 2006). Invasive species often upset the entire ecosystem balance, driving less competitive species into extinction and fundamentally altering the food web. High profile examples include the proliferation of zebra mussels in the Great Lakes--which have caused the decline in many native species and caused many industrial problems--and the Nile perch, which caused the extinction of hundreds of aquatic species in Lake Victoria. Invasive species are listed as the second greatest source of species extinctions (Wilcove et al, 1998).The figures at the right illustrate the interrelations between biodiversity, ecosystem services, and risks; species invasions is shown at the far right under "risks."
 
Invasive species are often transported via ballast water, or water taken on-board ships to keep it level in water. The water is taken from the starting point and then released at the end point--along with any organisms living inside. High risk ballast in regards to transport of invasives is water taken onboard in a freshwater or estuarine port as those organisms have a high chance of surviving in their new environment (Portland University, 2006). Invasives are also released intentially-as with unwanted pet release or through aquarium dumping--such as the release of the red-eared slider in the United States.

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    For parameters that are found to be below the standards, the source of the contamination should be identified. For point-source pollutants that were discharged before the implementation of the law, the perpetrator shall be notified of their infraction and mandated to stop the discharge and also be given a time frame (suggested time is a year) in which the pollutant's effects must be mediated in order for business to continue. For point-source pollutants that were discharged after the implementation of the law, the perpetrator must pay a fine in to cover the expense with regard to the environmental damage.           

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Invasive Species Transport !01178_lr.jpg|width=477,height=403!Sediment in a ballast tank; this sediment can host aquatic invasives. Source: NOAA 

For international ships, the current wisdom is that the country should require that in order to come into port, the ballast water must be exchanged at sea, past the continental shelf. The idea behind this is that the a species can only establish itself if its biological needs are met and changes in salinity and water temperature as found between fresh or estuarine waters and open ocean are great enough to kill most potential invasives.(Portland State University, 2006)

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(6)    Soils and root systems filter nutrients and pollutants (especially from agriculture and residential areas) before they reach surface areas from groundwater (Haberstock, 2000). !DCP00013.JPG!The vegetation on the sides of this waterway are an example of a riparian buffer. Source: USGS

 
These functions are not only important to the biota that lives in these regions year round, but also to anadromous species that come to spawn. For example, salmon require clean gravel for spawning; if silt settles over the gravel, it not only destroys suitable spawning substrate, but it can also smother eggs and the invertebrates that juveniles feed upon (Haberstock, 2000). Haberstock also reports that branches and other woody structures provide places for invertebrate prey to live, as well as structural habitat and varied flow patterns that are important for salmon. The improved water quality provided by riparian buffers and the cooling effect they provide are also critical (Haberstock, 2000).

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States should impose a permitting process for dams so as to have a direct role in the planning and implementation of regulations. For dams that have not yet been built there are many steps that can be taken to minimize the impacts. First, efforts should be extended to maximize energy and water efficiency as much as possible; in the past, increases in technological efficiency, recycling, enforcement of environmental legislation, and industrial minimization of intensive water use resulted in a water consumption rate increase much lower than the population demand pressure (WCD). This can be seen as a cost effective method, considering that large-scale dam projects require an incredible amount of capital and are usually both over budget and are completed later than scheduled (WCD). However, if a dam is definitively needed, research should be thoroughly conducted to determine the environmental impacts. The World Commission on Dams reports that many of the negative impacts from dam construction resulted from complications that were unforeseen; it predicts that use of environmental impact assessments could significantly lower these effects (WCD). A State should consider requiring the implementation of these assessments for any project proposed within the permitting process. Furthermore, proper placement of dams (such as on tributaries rather than on a main branch) and the use of minimal numbers of dams on a given river (because multiple dams can have cumulative effects, such as the dams leading to the Aral sea, which decreased water flow to such an extent that an increase in salinity and pollutants caused the entire fishery to collapse at a cost of approximately $1.25-2.5 billion per year) should be legislated by governments as these restrictions can minimize the large-scale negative impacts of large dams (WCD). Once these data are collected, the dam planning may begin; in this way, the dam design can take into account such features as gates that allow managed flood releases on a scale that can mitigate effects to the ecosystem; the permit for dam construction can require these provisions. The use of such managed floods in Kenya has been economically favorable by maintaining sectors of the economy that relied upon flows that would have been blocked entirely by damming (WCD). These floods help to release nutrients and sediments and help lessen the impact of the dam overall (WCD). These managed floods should be tailored to a specific river, as flood cycles are highly unique. It is important, however, that all such planning occurs before dam construction, as post-construction mitigation techniques have not been shown to be effective; the WCD reports rates of 20% effectiveness. It is possible that the IFIM (Instream Flow Incremental Methodology), as described earlier in (LINK TO WATER QUALITY ASSESSMENT AND LEGISLATION) could be used to help predict the effects of a dam and the effects of controlled flooding. !damphoto.gif!Source: USGS 

In terms of fish passage, fish passes have a very low success rate currently. In Norway, fish passes report a 26% rate of "good efficiency" and 32% of no success at all (WCD). In many parts of the world, fish passes are not used at all. Also, even with fish passes, fish often suffer from a lack of environmental cues (like currents) that help them find their spawning site (WCD). However, properly designed fish passes (specific to each dam and species of intended use) do hold promise; in Pennsylvania, fish passes were ineffective until tailored to the American shad, at which point they became very helpful in shad restoration (Richardson). Fish hatcheries and stocking may also be required to augment populations until the spawning routine is re-established with the dam in place; successful restoration of American shad and striped bass required such measures (Richardson), and these methods are likewise advocated by the WCD. The creation of artificial wetlands around shallow dam can also help mitigate dam impact by providing new habitat (WCD). Our recommendation is for governments to require dams to create a fish pass specifically designed for that river and its species or to pay a yearly fee to the government which can be used for species restoration and research; the law can stipulate these provisions if the company wishes to operate.

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