The next time you think about chucking popcorn, or the last bite of your shawarma, into the ebbing tide along the seafront at Muttrah corniche, watch out... Besides being liable for a heavy fine, you could be counted among the scores of citizens/residents (in Oman and around the world) who don't give a damn about the aquatic ecosystem and bring about environmental doom for everyone in the city by their irresponsible acts!
It is a common sight to see people throwing leftover eatables, bread, fruit-peels (besides, paper pouches, plastic bottles, cola cans) into the waters, supposedly with the good intention of feeding the fish. However, experts say, throwing foodstuff in the sea, in fact, harms the fish and other aquatic animals since it disturbs the balance of their ecosystem through a process called 'eutrophication'.
Eutrophication is the enrichment of water as a result of an increase in nutrients, which can have a negative impact on the marine and coastal environment, including algal blooms, increased growth of macroalgae, increased sedimentation and oxygen consumption, oxygen depletion in the lower layers of water and, sometimes, the death of benthic animals (organisms on the sea bed) and fish.
This can cause serious problems in the coastal zone through disturbance of the ecological balance and disappearance of fish.
The corniche coast is rich in aquatic biodiversity and home to many varieties of fishes like hamour, sherry, kingfish, crabs and shellfish. Throwing of food into the water leads to oxygen depletion as rapid oxygen consuming fungi and bacteria develop on the floating unconsumed nutriments, creating a deficiency in the oxygen level which forces marine inhabitants to retreat to other areas.
The consequences have even started to reflect at some of the spots. "The sea area near to the Muttrah Souq gate used to have a beautiful ecosystem comprising of seagulls, crabs and fish. However the fish and crabs are slowly retreating from the area (the area where you usually see people feeding fish). The beautiful view is more or less ruined now," says Zulfikar Ali, expert Biotechnologist, and dean of the IGNOU (Indira Gandhi National Open University) center in Muscat.
Although not a cause of concern right now in Oman, steps needs to be taken to prevent eutrophication beforehand as this is recognised as a widespread pollution problem worldwide, including Europe and America, according to marine biology experts.
Pollution the culprit
Eutrophication is often the result of pollution, particularly the release of sewage effluent and other waste material like industrial and agricultural run-off. Regretting there was no legal provision, as of now, to keep a check, Salim Mohammed Hamed Al Ghamari, member of the Musact municipal council, Muttrah region, said many people, especially small business owners like butcheries and vendors from the nearby fish market dispose waste directly into the water. In some instances, even sewage water is being directly discharged into the sea.
"We don't know currently if the waste material is treated or not before being disposed. And not only Muttrah, the situation might be even worse in interior areas where there is little or no check at all," Ghamari said.
Keeping the city green and its resources clean is the responsibility of residents. They must feel responsible for their actions and think sensibly as to what might be the consequences of their actions.
Salim Mohammed Hamed Al Ghamari
Member, Muscat Municipal Council, Wilayat Muttrah
Experts believe it also occurs naturally in situations where nutrients accumulate, like when eatables are thrown in water, or where they flow into systems on a regular basis.
"Eutrophication promotes excessive plant growth and decay, favouring simple algae and plankton (microscopic plants) over other more complicated plants, causing a severe reduction in water quality. Enhanced growth of aquatic vegetation (phytoplankton) and algal blooms disrupts normal functioning of the ecosystem, causing a variety of problems such as a lack of oxygen needed for fish and shellfish to survive. The water becomes cloudy, typically coloured with a shade of green, yellow, brown, or red," said a scientist at the Aquarium and Marine Science and Fisheries Centre, adding that the process also decreased the value of water-bodies for recreation, fishing, hunting, and aesthetic enjoyment.
Commonly caused by human activities, the process could accelerate the rate at which nutrients enter an ecosystem. Runoff from agriculture and development, pollution from septic systems and sewers, and other human-related activities increase the flow of both inorganic nutrients and organic substances into ecosystems, leading to the growth of harmful microbes, said the scientist.
A bigger invisible threat
Eutrophication leads to decreased biodiversity and increased toxicity, according to Zulfikar. "When an ecosystem experiences an increase in nutrients, primary producers reap the benefits first. In aquatic ecosystems, species such as algae experience a population increase, termed as algal bloom."
Algal blooms limit the sunlight available to bottom-dwelling organisms and cause wide swings in the amount of dissolved oxygen in the water. Under eutrophic conditions, dissolved oxygen greatly increases during the day, but is greatly reduced after dark by the respiring algae and by microorganisms that feed on the increasing mass of dead algae. "When dissolved oxygen levels decline to hypoxic levels, fish and other marine animals suffocate. As a result, creatures such as fish, shrimp, and especially immobile bottom dwellers die," the scientist elaborated, adding that, in extreme cases, anaerobic conditions promotes growth of bacteria such as Clostridium botulinum that produce toxins which are deadly to birds and mammals, creating dead zones, where no life form could survive.
Some algal blooms, also called nuisance algae or harmful algal blooms, are also toxic to plants and animals. The toxic compounds can make their way up the food chain, resulting in animal mortality. "When the algae die or are eaten, neuro- and hepatotoxins are released which can kill animals and may also pose a threat to humans. An example of algal toxins working their way into humans is the case of shellfish poisoning. Biotoxins created during algal blooms are taken up by shellfish (mussels, oysters, shrimps etc.), leading to these human foods acquiring the toxicity and poisoning humans.
Examples include paralytic, neurotoxic, and diarrhoeic shellfish poisoning," revealed the scientist. According to him, other marine animals can be vectors for such toxins, as in the case of Ciguatera, a predator fish that accumulates the toxin and then poisons humans.
Our city our responsibility
Salim said the onus primarily lay on people to protect marine resources. "Muscat is a clean and green city. It provides a source of living, and leisure and entertainment to a vast population coming from various backgrounds. But, people must protect nature and natural resources besides the culture and heritage of the place," he said, adding that water resources were the backbone of the country and its economy.
Salim stressed that areas like Muttrah Corniche - a popular tourist spot, acted as a conjugation between sustenance and entertainment, and must be protected at all costs. Strict preventive measures should be taken to curb irresponsible behaviour at this locale, he added.
Emphasising the need to sensitise people towards being more accountable for their actions, he said the municipality plans to implement strict rules, including big fines, for throwing garbage and foodstuff into the water, or polluting the area, within the next year. "People don't realise the consequences of their actions. Even the smallest careless step could result in a cause of grave concern in the future."
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