The water of the mangrove ecosystem and surrounding coastal areas are gradually shrinking due to the intense destruction. Therefore, the effects of the physicochemical properties of the habitat water on the in-habitant species must be studied. Scylla sp. is involved in the food chain and bioturbation structure formation in mangrove forests. Five major electronic databases, such as PubMed, Scopus, Web of Science, AGRICOLA, and Google Scholar, were systematically searched to review the cause and effects of influencing abiotic factors, mainly physicochemical properties of habitat water, including water pollution on Scylla sp. Responses of mud crabs at biochemical, molecular, physiological, growth, reproduction, and production level were independently reviewed or in relation to physicochemical properties of habitat water, pathogens, heavy metals, and harmful chemicals present in their habitat water. Review results suggest that these crabs are mostly under threats of overfishing, varied physicochemical properties of habitat water, pathogens, heavy metals, and chemical toxicants in water, etc. At low temperatures, the expression of calreticulin and heat shock protein-70 mRNA expression is elevated. Like melatonin, the hormone serotonin in mud crabs controls ecdysteroids and methyl farnesoate at 24 °C, 26 ppt salinity, and pH 7.2 of habitat water, facilitating their reproduction physiology. Xenobiotics in habitat water induce toxicity and oxidative stress in mud crabs. These crabs are prone to infection by white spot and rust spot diseases during the winter and spring seasons with varied water temperatures of 10–30 °C. However, elevated (65%) weight gain with higher molting at the juvenile stage can be achieved if crabs are cultured in water and kept in the dark. Their larvae grow better at 30 ± 2 °C with salinity 35 ppt and 12 hL/12 hD day length. So, monitoring habitat water quality is important for crab culture.

The disease COVID-19 caused by SARS-CoV-2 is the third highly infectious human Coronavirus epidemic in the 21s⁢t century due to its high transmission rate and quick evolution of its pathogenicity. Genomic studies indicate that it is zoonotic from bats. The COVID-19 has led to significant loss of lives and a tremendous economic decline in the world. Generally, the population at risk of a fatal outcome are the elderly and those who are debilitated or are immune compromised. The fatality rate is high, but now is reduced after the development of preventive vaccine although an effective treatment by drug against the virus is yet to be developed. The treatment is narrowed to the use of several anti-viral drugs, or other re-purposed drugs. Social distancing, therefore, has emerged as a putative method to decrease the rate of infection. In this review, we summarize the aspects of the disease that is so far have come to light and review the impact of the infection on our society, healthcare, economy, education, and environment.

Salinity is a decisive abiotic factor that modulates the physiology of aquatic organisms. Salinity itself is modulated by various factors—most notably by anthropogenic factors. In coastal regions, increasing salinity is observed mostly due to the elevated rate of evaporation under high temperatures, especially under global warming. In addition, many other anthropogenic factors, climatic factors, chemicals, etc., also contribute to the changes in salinity in coastal water. Some of these include rainfall, regional warming, precipitation, moisture, thermohaline circulation, gaseous pollutants, dissolved chemicals, wind flow, and biocrusts. Salinity has been found to regulate the osmotic balance and, thus, can directly or indirectly influence the biomarkers of oxidative stress (OS) in aquatic organisms. Imbalances in OS potentially affect the growth, production, and reproduction of organisms; therefore, they are being studied in organisms of economic or aquacultural importance. Salinity-modulated OS and redox regulation as a function of phylum are covered in this review. The literature from 1960 to 2021 indicates that the altered OS physiology under changing salinity or in combination with other (anthropogenic) factors is species-specific, even within a particular phylum. Thus, knowing the response mechanisms of such organisms to salinity may be useful for the management of specific aquatic animals or their habitats.