Assessment of Anthropogenic Marine Debris in Four Beaches Along the Coastline Gulf of Guinea South West Nigeria Anthropogenic Debris in Four Beaches Along

Anthropogenic marine debris is permeating in the marine environment and World’s shores present a major sink. This study assessed the anthropogenic marine debris on four beaches along the South West Nigeria shoreline was sampled between November to December 2019. The marine debris was categorized into eight categories: Plastic, Glass, Metal, Wood, Fishing Aquaculture, Cotton fiber, paper and styro foam. The relationship among the abundances of each category were examined. The abundance of each anthropogenic marine debris category were; 2331/m², 504/m², 625/m², 474/m², 508/ m², 518/m², 1044/m² and 826/m² (Plastic, Glass, Metal, Wood, Fishing Aquaculture, Cotton Fiber, Paper and styrofoam) respectively. Plastic was most abundant item across the beaches shoreline, it had highest loading value (0.92) among all the AMD categories. The study area was non-significantly related abundance of AMD. Similarity evidence was recorded in the pooled data set of hierarchical analysis showed the site had a related cluster across the sites.

are commonly identified debris [17]. There is variety of causes of leakage including direct dumping, littering, as well as wind or water-borne transport such as via storm water runoff, from open dumps and landfills [17,18]. The underlying and common use of plastic for diverse applications, light weight nature, durability and low price made it commonly used [19]. Annual plastics production has increased greatly over the globe. Enormous quantities plastic is consigned to landfill, recycled, or are still in use. Nevertheless, huge volumes end up as marine debris as a result of insufficient treatment capacity, accidental inputs, littering, or illegal dumping [17]. The primary compositions of plastics are mostly polyethylene and polypropylene, recorded on the survey sand Island, Midway Atoll [20]. Marine debris can be categorized according to two main source categories: Ocean and Land-based debris, depending on where Anthropogenic Marine Debris entered the marine environment [2].
Ocean-based AMD sources include waste from shipping, fishing, oil platforms and aquaculture [21][22][23][24]. Land based AMD might enter the marine environment by rivers, outflow from industries, harbors, unmanaged landfills, sewage waters, extreme events (tsunamis hurricanes), or through direct littering by beach visitors [25][26][27][28][29]. The studies of Jamback, et al. [30] estimated over 8.4 million tons of plastic waste entering the ocean annually from land based sources. The composition of marine litter is very diverse consisting of plastics ( such as bags, bottles), wood (boxes and fragments), glass(bottles), metals (cans, aerosol containers), rubber (tires, boots), cigarette butts, etc [31]. The primary plastic items of marine litter consist of bottles, plastic bags and packaging materials. Wood and glass correspond to another 10% of total marine litter each, some of the most common items of marine litter between 1989 and 2007 (at the global level) included plastic bags (9.4%), caps/lids (9.1%),food wrappers (8.9%), cups and cutler (7.2%) and small (less than 2.1), plastic beverage bottles (5.5%) [32]. Island Morphology can be affected by wind and ocean currents, it influences plastic debris accumulation and deposition [33].
Variations of AMD abundance over a period of time might be linked to the socio-economic and educational conditions of a country; pro-environmental behavior such as adequate waste disposal is generally higher in developed countries [34]. Developing countries focus on economic growth, often at the expense of environmental care. Environmental degradation might increase as the economy grows, up to a point where economic development leads to higher environmental awareness, thus, identification of the sources of Anthropogenic Marine Debris is indispensable for satisfactory mitigation strategies, since it is of global concern [35].
Nigeria has a coastline of 853Km, a maritime area of 46,500km 2 and an exclusive economic zone of 210,900km. Nigeria covers a total of 923,768km 2 along the West African Gulf of Guinea. The coastal areas stretch inland for a distance of about 15km in Lagos in the West, which is the commercial capital of Nigeria. For a busy commercial activities in Lagos Nigeria, thus the amount of AMD of beaches are expected to be high, with a trend to increase over period. The data collected in this study will provide base-line information on Anthropogenic marine debris in four beaches along the coastline of south-West Nigeria, to a. Determine composition, b. Estimate abundance and spatial patterns on the four beaches.

Materials and Methods
The study was conducted on four sandy beaches, along the larger quadrats (placed in locations that visually appeared to have the maximum and minimum amount of debris [36]. All natural and artificial debris with a depth of 5cm in the quadrats was sieved out. All AMD items found at each station were collected and counted after classifying them according to the following categories: Plastics, Stryofoam, Papers (cigarette butts), cotton(fibre), fishing aquaculture, woods, metals, and glass. Summary statistics were calculated overall and by site. Items making up 1% or more of the debris category mean total were tabulated. ANOVA was used to test for site differences in total debris, Duncan and Fisher's Least

Results
The mean value (mean value ±STE) of AMD surveys across the sites were 41.       The plastic abundance was highly variable between the four sites.
The scree plot (Figure 2) shows that the first two principal components are significant for the variation among the stations based on their Anthropogenic marine debris compositions.
This is because the plot starts to flatten out at third component.

Discussion
The abundance and composition of Anthropogenic marine debris across the four beaches (Elegushi, Oniru, New-Lekki and  [39,40]. Meanwhile, glass and metal might last longer in the upper zone of the beach than paper and plastic which are blown away by strong onshore winds; that usually occur along (Nigerian coast), thus ending up in the dunnes or behind shoreline [37,[41][42][43]. Plastic are practically always dominant on shores worldwide, where they often reach correspondingly high proportion as recorded in this study (>30%).
The foremost cause for this is the extensive use of plastic for a diversity of purposes and its long persistence in marine environment [44]. The type and similarity of AMD composition across the local shore found herein intensely indicate that it has local sources which and Aquaculture activities such as landing sites was observed in the beaches of this study, however, fishing and aquaculture contributed noticeably to the Anthropogenic marine debris, but did not reach the high input observed from previous reports of ( Thiel et al., 2013) , most likely due to high contributions from other sources (beach users) in the south west Nigerian coastline [45][46][47][48][49][50][51][52][53]. Similarly no indication was found that some of the shorelines accumulated AMD than others.

Conclusion
The results propose that a high proportion of the AMD on local shores has been directly deposited there by beach user. The abundance of the marine debris on those beaches evidently specified sources from anthropogenic activities such as recreational tourism, fishing and aquaculture, shipping. This emphasizes the strong need for local solutions in the pursuit for keeping local beaches along the Nigerian coastline clean.