İSTANBUL’DA KIYI KİRLİLİĞİ

Istanbul’da 2013 ve 2016 yillari arasinda kiyi ve plaj temizliginde toplanan deniz ve ambalaj atiklarinin poset sayisi , deniz yuzeyi temizligi ile toplanan atik miktari (m³), yosun calismasi ile toplanan atik miktari (kg) ve dere islahi ile cikarilan camur miktari (m³) verileri analiz edilmistir. Bu miktarlarda mevsimsel degisiklikler tespit edilmistir. Kiyi temizligi sirasinda toplanan ambalaj posetlerinin miktarinin zamanla asiri yukseldigi ve 2016'da en yuksek seviyesine ulastigi gorulmustur. Piknik alanlarindan tasinan atiklardan dolayi yaz aylarinda ve yogun yagisla suruklenmeden dolayi eylul ayinda yuksek degerler gozlenmistir. Ancak kis mevsiminde tum parametreler icin dusuk degerler goruldu.  Atik miktarlarindaki bu artis, atiklarin atilmasi yerine plastik torbalarin ve siselerin geri donusturulmesi veya yeniden kullanilmasi gibi cesitli onlemler alinarak giderilebilir. Daha temiz bir deniz ve sahil icin, bu onlemleri tesvik etmek amaciyla kamu egitimi gelistirilebilir. Ayrica, plastik posetler alisverislerde ucretsiz verilmek yerine satilmasi gibi ekonomik tedbirler alinabilir.


INTRODUCTION
Marine debris is mostly plastic (Pasquini et al., 2016). Plastic packaging pollution results from the accumulation of waste from marine transportation (Scott, 1972). Tourism, fishing, shipping and passenger vessels increase marine debris (Polasek et al., 2017). According to a study of Catalan shores by Ariza et al. (2008), urban beaches had a higher density of waste storage compared to urbanized beaches during the swimming season (Ariza et al., 2008). Plastic bag waste, when seen at high levels in municipal waste water, causes environmental problems such as resource depletion, blocked waterways, harm to animals and damage to soil, landscapes and trees (Bahri, 2005). Plastic waste increases with the growth of the economy, human activity and industrial processes. It is difficult to transport plastic waste because of the deteriorated properties of the plastic. In addition, the harmful effects of plastics and associated toxic hazards are a real threat to human health and the environment. Sea birds and turtles can eat floating waste. As a result they can choke or inhibit their digestive system (Ocean Conservancy, 2016). Decompositions of coastal plastic wastes are disturbed at much higher thermal values than new plastics (Khariri, 2012). The decomposition of plastics on the beaches results in persistent organic pollutants carried to the water by wind and currents (Andrady, 2011). Solid waste production increases along with population and local food preparation habits often produce food waste. Focusing on waste disposal instead of waste prevention causes excessive use of plastic bags and containers (Maziku, 2014). If plastic packaging is not properly collected, it can reduce ocean productivity (Lachmann, 2016). Golik and Gertner found that the contents of beach garbage were mostly related to recreational activities, containing such items as beverage bottles, food containers, cosmetics, plastic bags, clothes, foam, rubber and cushions. The bag of beach garbage contained 71.6% plastic material, 7.9% wood, 5.7% metal, 3.1% glass and 11.7% other materials (Golik and Yaron, 1989). Plastic does not sink and moves to any place in the world with currents (Isangedighi et al., 2018).
One way to reduce plastic waste is awarding fishermen for bringing their fishing gear on board when returning rather than throwing it into the sea. Because most sea waste comes from the land and contains plastic, economic instruments can help reduce marine litter (Oosterhuis et al., 2014). Marine debris can also be cleaned by government agencies and through campaigns that promote public participation. Bottles and plastic bags can be reused or recycled if they can be prevented from being thrown around the sea (Liu et al., 2013). The major ocean plastic accumulation zone can be characterised and quantified by The Great Pacific Garbage Patch model (Lebreton et al., 2018). Clean and efficient transportation can be made by Green Port concept protecting marine aquatic life and ecosystem (Satir and Dogan-Saglamtimur, 2018). In this study, collected wastes (marine debris, packaging, sea surface waste, moss and sludge) from the Istanbul coast between 2013 and 2016 were statistically analysed. Association between the collected wastes and population was determined by Pearson correlation. Then coast waste management and shore protection measures were recommended.

STUDY AREA
Our study area is the Marmara Sea near Istanbul, Turkey. The Marmara Sea is a recreational area for people in Istanbul, which is the most crowded second city in Europe ( Figure 1).

MATERIALS AND METHODS
Beach and coast cleaning squads clean floating waste and waste on the shore, covering 600 km of coastlines, piers, rocky shores, beaches and sea surfaces during the year. 31 teams include 186 staff were working in different locations (Avcılar, Silivri, Yenikapı, Catalca, Halic, Karakoy, Sariyer, Uskudar, Beykoz, Agva, Kadikoy, Tuzla, Sile, and Eyup) across the Istanbul. In addition, they also clean the sand on the beach during the swimming season (Figure 2a  Collected wastes were statistically researched and Pearson correlation in Excel was used to determine the relation with population and migrants.

RESULTS
We analyzed the number of seaside pouches and packaging pouches collected during coast and beach cleaning between 2013 and 2016 (Figures 3, 4, 5          We also analyzed the amount of waste (m³) collected during sea surface cleaning, the amount of waste collected by moss work (kg), and the amount of sludge removed during stream rehabilitation (m³) (Figures 9, 10 Table 1).
The values representing the Pearson correlation between Istanbul's total population and average values of parameters were 0.67 (quantity of seaside pouches in coast cleaning), 0.99 (quantity of packaging pouches in coast cleaning), 0.83 (quantity of seaside pouches in beach cleaning), 0.7 (quantity of packaging pouches kg in coast cleaning), 0.88 (quantity of seaside pouches in coastal cleaning) and 0.75 (quantity of packaging pouches in beach cleaning). The Pearson correlation coefficient between Istanbul's population and the minimum value of amount of waste collected during sea surface cleaning was 0.93, and Pearson correlation coefficient between Istanbul's population and the minimum value of waste amount collected during moss work was 0.82. Therefore, we determined the strength of the positive linear association between variables using Pearson correlation. Correlation values showed that pollution increased along with population between 2013 and 2016. There was a negative association between pollution parameters and 10-14-year-olds who migrated to Istanbul. There was also a negative association between pollution parameters and 25-34-year-olds who migrated to Istanbul. On the other hand, there was positive association between pollution parameters and 0-9, 15-24, 35-44 and 50-90-year-olds who migrated to Istanbul.

Figure 11:
The amount of sludge removed by stream rehabilitation (m³)

CONCLUSIONS
The amounts for all parameters were high during the summer months and in September, but lower in winter. Also, the quantity of packaging pouches collected during coast cleaning in 2016 was much higher than in previous years.
The maximum values of waste (m³) collected during sea surface cleaning and moss work (kg) were in 2014 and 2013, respectively, and the maximum value of sludge removed during stream rehabilitation (m³) was in 2013. The Pearson correlation values showed a strong positive association between Istanbul's population and the average values of seaside pouches and packaging pouches collected during coast cleaning, seaside pouches collected during beach cleaning, packaging pouches collected during coast cleaning, seaside pouches collected during coastal cleaning, and packaging pouches collected during coastal cleaning. The Pearson correlation coefficient between Istanbul's population and the minimum values of waste collected by sea surface cleaning or moss work was also high. Therefore, pollution increased along with population between 2013 and 2016. There was a negative association between pollution parameters and people aged 10-14 and 25-34 who migrated to Istanbul; however, we found a positive association between pollution parameters and people aged 0-9, 15-24, 35-44 and 50-90 who migrated to Istanbul.
The amount of land-based marine litter from 192 countries (China, Indonesia, the Philippines, Vietnam, Sri Lanka, Thailand, Egypt, Malaysia, Nigeria, Bangladesh, South Africa, India, Algeria, Turkey, Pakistan, Brazil, Burma, Morocco, North Korea and the United States etc.) in 2010 was 4.8-12.7 million metric tons and plastic marine debris from Turkey in 2010 was between 0.07 and 0.19 million metric tons (Jambeck et al., 2015). Therefore the marine debris from Istanbul coast between 2013 and 2016 was extremely lower than the marine debris from other countries and Turkey in 2010. 300 bags of debris comes from ships dumping offshore were collected in 2017 on beaches in Istanbul's Kilyos (Daily Sabah with Dogan News Agency, 2017) A survey of the Dutch coast from 2000 to 2006 found 500 tons of debris on sea floor (Elias, 2018). Kuwait Dive Team had collected more than 2700 tons of marine debris in the last decade from Mediterranean Sea, Red Sea, and Arabian Gulf (Ocean . And these amounts are high with compare to Istanbul coast's yearly values. The findings of this work can help support efforts to improve the coasts of Istanbul and its beaches and waste management, and may benefit those responsible for waste production and management characteristics. Coast waste management can reduce waste from coast through material reuse, recycling and composting. Campaigns of waste abatement and awareness-raising such as 'Love Food, Hate Waste' programs, 'Get it Sorted' campaign (Willis et al., 2018) can be built to reduce waste. It has been recommended that future work should be compositon, origin, and abundance of marine debris along Istanbul coast. The adverse environmental impacts of plastic bag waste, its main causes, and short-and long-term remedial policies and technical packages should be identified. Changes in consumer behaviour, such as the rational use and reuse of plastic bags, should be encouraged. To this end, people can be educated through public awareness campaigns about the production, use and disposal of plastic bags, and the surrounding effects of plastic waste. Compostable bags that perform well should also be developed, and reusable bags can be sold at easily accessible places. Additionally, plastic shopping bags are currently free, but a fee could be added to promote more responsible use.