Anthropogenic Marine Debris Accumulation in Mangroves on Penang Island, Malaysia

Abstract

Knowledge on anthropogenic marine debris (AMD) distribution and accumulation dynamics in mangroves is limited. To address this shortfall, abundance, sorting, and diversity parameters of AMD were evaluated in Penang’s urban and peri-urban mangroves. Debris were counted and classified across transects parallel to the coastline at progressively higher water marks. Plastic percentages make most of the AMD across all sites. More AMD were retained in the urban sites, consistent with larger population density. Diversity of debris was consistent with land use and livelihood of the population in each area. The greatest differences in abundance, diversity, and evenness were recorded between the lower intertidal zones and the remaining inner transects consistent with sorting towards the coastal edge in favour of plastic items. Differences across transects and sites suggested: 1) the main body of the mangrove efficiently retained debris with little sorting; and 2) debris deposited closer to the edge are increasingly sorted and lost to the water body in favour of smaller plastic items. The findings show that mangroves are vulnerable to accumulation and retention of potentially harmful debris, with evidence of a less efficient retention and selective sorting of materials back to the water body closer to their coastal edges.

Effects of seasonal variation on the characteristics of stranded marine debris within Rambut Island Wildlife Reserve, Indonesia

“…It remains possible that varying root structures found among different types of mangroves can impact the density of marine debris that becomes trapped within the associated ecosystem (Luo et al, 2021). This study is supported by research carried out on Penang Island, Malaysia (Yin et al, 2020). This study highlights disparities in the number of marine debris discovered in two varieties of mangroves, Rhizophora mucronata and Avicennia sp.…”

Marine Litter Impacting Beaches and Mangrove Forests: A Characterization and Assessment within the Archipelago of Jambelí, Ecuador

“…(2019) observed high litter content in mangrove forests close to rivers that transport large items from nearby coastal areas. High concentrations of litter items were also observed in mangrove forests close to urban areas in Penang Island, Malaysia (Yin et al ., 2020), and in the Paranaguá Estuarine Complex, Brazil (Possato et al ., 2015). As has been observed on the Colombian Caribbean coast, natural events such as hurricanes can also have an important implication for the distribution and accumulation of litter in mangroves (Garcés-Ordóñez, Saldarriaga-Vélez, and Espinosa-Díaz, 2021).…”

Intertidal zonation of live benthic foraminiferal assemblages from mangrove environments around south-west Penang Island, Peninsular Malaysia

“…The dense aquaculture activities (i.e. shrimp ponds and fish cages) in the mangrove forests might also result in high OM in the sediments, which has been reported by some authors (Chee et al ., 2015; Zolkhiflee et al ., 2021). In Matang mangroves, the high presence of A. mexicana , together with Haplophragmoides wilberti , was due to the enrichment of OM by leaf litter and other bioorganic substances (Satyanarayana et al ., 2014).…”