Wind Power, Ecology and Human

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Loss of marine species is also one of the minus influences brought by the installations of offshore wind turbines. Stationary or slow-moving animals, which are unable to move, would be killed directly beneath the jack-up vessels or piles. Likewise, marine organisms can suffer from suffocation by deposition or accidental release of drill cuttings (Gray 151). Moreover, it can also result from destruction of habitats. As mentioned previously, destruction of habitats interferes the local food chains and food webs. The population of certain species will drop rapidly when they lose the original habitats but cannot accommodate to a new one immediately. Changes in population size of any unit in a food chain or a food web affects the population size of the other species in the same system due to the relationship of prey and predator. As a result, there is a potential risk that the other species will die, causing the loss of more breeds.

Furthermore, electromagnetic fields (EMF) produced by the buried electrical cables interconnecting wind turbines with the consumer power supplies is also a disadvantage caused. Certain fish species are electrosensitive that they adopt geomagnetic cues to assist navigation. As the magnetic component of EMF is of similar strength to that of the Earth, this affects the detection of electromagnetic signals from the fish (Ohman 630-633). Consequently, fish will hunt poorly and fail to complete migration if they have to travel across the cables.

The impacts of noise and vibrations produced by wind turbines on marine organisms, especially the acoustically sensitive species, are growing concerns. The intensity of noise and vibration, and hence disturbance are particularly severe during the construction stage. Natural sound and pressure waves create a sound spectrum which could be distorted if interfered by sound pollution from the creation and operation of wind turbines (Popper 455-489). At an intense level, this will cause occasional physical injuries in fish. Meanwhile, as fish use sounds to gather information about predators, prey, competitors and mates, and for the location of migration routes or feeding grounds, noise pollution leads to higher mortality rate due to increased exposure to predators, growth and reproductive reduction due to diminished access to prey or mates.

Not only do wind turbines disturb marine biodiversity, but also avian. Collisions between birds and wind turbines pose threat to birds. In general, collision risk depends on several factors like regions, seasons, weather conditions and the design of wind turbines. The risk is greater in or close to areas that are frequently used for feeding, roosting or migratory pathways and local flight paths, and during migratory seasons. Large birds which cannot fly have a smaller risk of colliding with a turbine structure. Reduced visibility due to poor weather conditions and darkness raises collision risk. Artificial illuminations of offshore wind turbines attract migrating birds and draw them into wind farm sites which are continually illuminated, thus increasing the risk of collision incidents (Huppop, Ommo, Jochen, Klaus-Michael, Elvira, and Reinhold 90-109).

While there are many negative effects associated with the establishment of wind farms, it cannot be neglected that it also brings benefits to biodiversity. There is an increasing amount of evidence suggests that, with appropriate design, sitting and management, MREI actually have the potential to produce positive environmental impacts (Wilhelmsson, Malm, and Ohman 775-784). Garette Gross, a scientist from UMKC in Kansas City, Missouri States, “The impact made on the environment is very little when compared to what is gained.” The initial carbon dioxide emission from energy used in the installation is “paid back” within about 2.5 years of operation for offshore turbines (Hall 6-7).

Although the construction of MREI destroys some natural habitats, some new habitats are created at the same time. Man-made structures placed on the seabed attract a lot of marine organisms. These towers and foundations act as artificial reefs, which can enhance fisheries and productivity. They are also used for habitat rehabilitation, for coastal protection and to attract eco-tourists (Clark and Edwards 5-21). The installation of a turbine increases the surface area available for organisms to colonize, thereby uplifting the fish stocks in the vicinity. Preliminary findings give support to this. Wilhelmsson found greater abundances of fish within the vicinity of wind turbines than in surrounding areas, although the species richness and diversity are lower than in the surrounding areas (775-784).

While underwater structures can function as artificial reefs, floating structures can act as fish aggregation devices (FAD). A number of manufacturers are currently developing floating turbines which, along with wave energy devices, will be anchored to the seabed, but will be free to move on the surface, or within the water column (Musial, Butterfield and Boone 4-5). Castro reviewed the effect of floating structures on fish aggregating behavior suggesting that wind farms may act as fish aggregation devices, resulting in catch rates in the immediate area between ten and a hundred times greater than in the surrounding open ocean (255-277). the cause can be a combination of the shelter provided by the structures, and the reduced fishing effort which is often found around offshore wind farms. With this finding, fishermen can take advantage of this phenomenon to increase their catches as many different kinds of fish species aggregate around floating objects.

Establishing marine-protected area (MPA) is one of the plus influences by the setting up of offshore wind farms. Regions around wind turbine installations will be enclosed within enforced exclusion zones for both safety and protection of the installations and the enclosed area can serve as MPA to most fisheries. MPA are increasingly being called for and used as a fisheries management, conservation and ecological restoration tool (Fayram and Derisi 597-605). Recent work has demonstrated that networks of MPA have a rapid positive effect on fish abundance (Russ R514-515). The introduction of networks of MPA associated with MPA will thus provide a powerful tool for restoring ecology. On top of protecting and enhancing fish stocks, the implementation of MPA will also enrich benthic biota by lifting the pressure from towed-bottom fishing gear, which have chronic effects on seabed communities and are likely to affect ecosystem function (Kaiser 137-155).

Wind has been contributing to human beings for long. The use of wind power can be traced back to ancient times. One of the earliest examples of adopting wind power is that the Babylonian emperor Hammurabi planned

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