Metal transportation mechanism by rainfall runoff as a contribution to the bioaccumulation in seafood.

Trace metal transport mechanism via rainfall runoff from soil to the water body in the context of the bioaccumulation in seafood was unprecedentedly investigated. Instead of a conventional simulation experiment at a laboratory, the twelve soil sampling sites were selected in the region (Windar Valley, Balochistan-Pakistan) reported with high trace metal content, and Threadfin Sea Catfish and Belanger's Croaker were caught from the adjacent coastal water body. The Pb, Cd, Ni, and Zn in soil samples were high in proportion; the average concentrations were 2793.8, 622.44, 331.33, and 440 in mg kg-1, respectively, as per expectations. Using ArcGIS, the soil sample results were extensively illustrated by the spatial distribution in the sampling regions. The Zn > Pb > Ni > Cd was found in pre- and post-rainfall fish flesh samples. Trace metals were higher in post-rain fish flesh samples than pre-rainfall samples, indicating that rainwater runoff could be the significant source for trace metal transport except for Zn. The Pb, Cd, Ni, and Zn elevated results were 0.80828 ± 0.17752, 0.12102 ± 0.03027, 0.71064 ± 0.24188, and 6.49223 ± 3.65094 in mg kg-1, respectively, in post-rainfall fish flesh samples. Appling chemometric tools revealed that Zn content depends on Zn-protein interaction, and Pb, Cd, and Ni contents significantly pertain to the rainwater runoff. Other probable transport routes for trace metals to the water body could be less responsible. The soil sampling region's NOAA HYSPLIT backward air trajectory showed that the air direction was mostly from ocean to land.

Ecosystem based approach to delineate coastal degradation of Hawks bay, Karachi, Pakistan.

Hawks Bay (HB) a renowned recreational beach, an important small scale fishery and nesting ground of an endangered turtle species encountering massive environmental degradation. Its eastern bay cover scattered mangrove patches and the western bay embraces sandy and rocky beach that terminus the area into great ecological and economic concerns. Here, we have figured out tendency of contamination entering in the ecosystem and elaborate food âˆ¼ web dynamics around HB. An integrated approach was applied to evaluate level of contamination in water, sediments, planktons, seaweeds, mangrove leaves, crabs and fishes. In the sampled population phytoplankton were comprises of (39 Taxa), zooplankton (21), crab (1) and fishes (9) from pelagic demersal domains. The concentration of copper (Cu), iron (Fe), zinc (Zn), lead (Pb) and chromium (Cr) were detected using double-beam Atomic Absorption Spectrophotometer (AAS). The trophic transfer (TTF), contamination factor (CF), pollution load index (PLI), bioaccumulation factor (BAF) and accumulation factor (AF) were calculated round the year. The CF reveals that the area is moderately contaminated whereas PLI (>1) indicate that area is massively polluted by the industrial wastes. Multivariate approach of Principle Component Analysis was applied using pooled data of TTF that defines PC-I (41.56%) and PC- II (31.44%) variability among axes. Evaluation of metal contamination from micro to macro and from surface to bottom exhibits considerable load being received by HB ecosystem echoes stringent actions to curb further degradation of an important area.