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We examined the temporal variation of heavy metals in different sexes of three brackish water shrimp species with emphasis on the relationship between Fulton's K condition indices and metal polluti...

This article discusses the temporal variation and stress of heavy metal accumulation in Scylla serrata (Forskal) with reference to sexes. Cd and Sn were undetected (i.e., below the method detection limits of 0.001 Cd mg/kg wet weight and 0.005 Sn mg/kg) in both sexes. However, Scylla serrata (Forskal) consistently exhibited high accumulation of As, Pb, Hg and Zn. Zn was the most abundant metal in both sexes. (Average Zn content in males and females was around 40.76 ± 2.51 and 45.10 ± 2.24 mg/kg wet weight, respectively.) Pb and Hg levels exceeded EU and Sri Lankan admissible limits on many occasions (0.02 Pb mg/kg wet weight and 0.5 Hg mg/kg wet weight). Bioconcentration factors (BCFs) of As and Zn from the water > 1 in both sexes indicating effective direct uptake from the water. However, temporal variation of Zn and Hg and the interaction between temporal variation of these metals and the two sexes were insignificant (P > 0.05). Nevertheless, temporal variation of Pb (P

Tropical coastal lagoons comprise several habitats, which have great importance for avifauna by providing nesting, roosting or foraging sites. However, various anthropogenic activities have caused coastal habitat degradation globally. To sustain conservation, it is crucial to understand the seasonal habitat utilization patterns of avifauna. Additionally, how coastal habitats are influencing terrestrial avifaunal distribution is not well documented. Therefore, this study was carried out to examine the habitat utilization patterns by aquatic and terrestrial avifauna in Batticaloa Lagoon in eastern Sri Lanka from September 2017–August 2018. Compared with past studies, our study indicated a lower diversity of aquatic birds. Findings revealed that 47% and 27% of aquatic and terrestrial avifaunal species, respectively occurred in all habitats indicating their utilization of different habitats as alternative habitats. However, terrestrial bird composition was more similar between the different habitats (compared with aquatic birds) as per non-metric multi-dimensional scaling (NMDS) plots. Overall bird density variation was significant with season and habitat. Considering the avifaunal density, both aquatic and terrestrial birds mostly preferred swamp habitat. Abandoned shrimp farms were least preferred by aquatic birds and terrestrial birds indicating that anthropogenic habitats do not provide many of the required resources that are provided by natural habitats. Mangroves (comprising true mangrove species and mangrove associates) support a relatively high diversity of terrestrial birds, but recorded the lowest diversity of aquatic birds. Suggestions were made to improve habitats to attract more species especially aquatic birds.

This article discusses bioaccumulation and temporal variation of heavy metals in three edible lagoon fish species with references to gender. Cd and As were undetected in the three fish species (i.e., below the method detection limits of 1 μg Cd/kg wet weight and 2 μg As/kg wet weight) irrespective of the periods, and Cd was undetected in the water too (i.e., below the detection limit of 0.0003 mg/L). Except for Zn (which was mainly available as Zn2+ in the water), Pb was present largely as low labile metal-chloride complexes and As as HAsO4 2− as per Visual MINTEQ, version 3.1. Bio-transfer factors of Sn (which was also undetected in the water; below the detection limit of 0.05 mg/L), Hg, Pb, and Zn were

The necessity to understand the relationship between cyanobacterial species abundance and water quality variations in coastal lagoons is crucial to develop strategies to prevent further cyanobacterial proliferation. This paper evaluates the relationship between water quality variations on the distribution of cyanobacteria during a 12-month period in Batticaloa Lagoon (Sri Lanka) using Redundancy analysis and Pearson correlations. Drastic variations in pH, temperature, salinity, dissolved oxygen (DO) and total phosphorus (TP) levels were reported, but not turbidity and NO3−. This brackish waterbody is hypereutrophic (TP levels > 0.1 mg/L). The cyanobacterial community contained 13 genera and 22 species. NO3−, TP and turbidity levels positively influenced cyanobacterial abundance during all seasons indicating that nutrient (largely phosphorus) and sediment entry control is highly crucial along with periodic monitoring of cyanobacterial growth.

Abiotic and biotic variables of coastal lagoons are highly heterogeneous in both space and time, and this heterogeneity complicates the assessment of lagoon ecological status. These variables are essential for monitoring and preserving of these fragile ecosystems and the resources and services they sustain. This study was designed to assess the effect of lagoon water quality on changes in fish abundance. In situ measurements of chemical and physical parameters of the Batticaloa lagoons were measured fortnightly by using a calibrated portable Hanna instruments over the different seasons from March 2012 to February 2013. Fish diversity indices for the main commercial species were calculated. Fish composition varied greatly according to the study site and the seasonal trends. Results reveal that the existing conditions, such as salinity dissolved oxygen, nitrate and pH had a strong effect on the fish community in the lagoon. The present study is commissioned to assess the seasonal variation and the status of the lagoon to make informed plans for the fishery of the lagoon patients to reap it successfully and sustainably.