Vegetative structure and zonal distribution of true mangroves in Shwe-Thaung-Yan coastal areas, Myanmar

The survey was conducted in the mangrove forests around the Magyi and Utto Creeks at Shwe-Thaung-Yan coastal areas in Ayeyarwady Delta region, April 2018. Transect lines were laid as lower, middle and upper, and quadrate plots based on Point Center Quarter Method (PCQM) P-DATA PRO were used. A total of 15 species of true mangrove was recorded. Rhizophora apiculata and Bruguiera gymnorhiza are the most dominant and distributed species in the study area. Followed by Bruguiera sexangulata, Cerop tagal and Rhizophora mucronata then remaining species. Zonation pattern of mangroves species as lower, middle, upper was also examined in study areas. Among than 1 species in Near Threaten (NT), 1 species in Critically Endangered (CR), 1 species in Endangered (EN) and remaining species are Least Concern (LC) had been considered according with IUCN red list. The environmental parameters such as water salinity and temperature, soil salinity, soil temperature and soil pH of study area were also recorded.

Gender is not a relevant matter in habitat selection of the longsnout seahorse Hippocampus reidi Ginsburg, 1933 (Teleostei: Syngnathidae)

Habitat selection in certain species may vary according to context and environmental conditions. Sexual differences regarding habitat use have been reported for several species, such as mammals, birds and fish, and have been explained by protection and food resource contexts. This issue is not well studied in seahorses, but it may provide useful data for the management of threatened species. The Longsnout Seahorse has recently been considered near threatened, but many gaps regarding its habitat use are still noted. Seahorses display a particular breeding characteristic, in which males carry the embryos inside a breeding pouch, therefore leading to supposed careful selection of breeding habitats, avoiding predation risks and choosing habitats with high prey availability. In this context, this study aimed to verify differences in habitat selection between male and female Longsnout Seahorse Hippocampus reidi specimens along the coast of the state of Rio de Janeiro. This study took place at 11 sites along the Rio de Janeiro coastline, in southeastern Brazil. Random belt transects (20x5m) were assessed, searching for seahorses and their holdfasts. Random quadrats (50x50cm) divided into 100 cells/each were placed along the transects and benthic cover was counted, in order to establish substrate availability. Results suggested that males select fewer substrate types than females, but no statistical difference was detected. Both male and female H. reidi specimens select mostly Sargassum vulgare as a frequent habitat. The strong association of H. reidi to these seaweed beds suggests vulnerability concerning the degradation of this habitat.

Transitional fishery: a new resource for global nutritional food and medicinal security

Sea and river junctions form lagoon, sites become largely marshy land with fresh water at upper approaching river reach and brackish water towards sea. Such bays are plentiful in numbers and visited by aquatic birds during the winter seasons. Previous studies established vast possibility of harvesting biological nitrogen (N) and phosphorus (P) through aquatic bird droppings viz Guano. The vast sizes and number of such sites have huge potential for fishery with differing in quality characters which is termed as transitional fishery in the present study. Objective of the present study was to bring impetus in this new category of fishery with scientific management so as to make the venture highly efficient and responsive, and enable harnessing plentiful benefits of nutritional food and medicinal security. The transitional fishery was considered as ecosystems and various networks of ecology of land, vegetation, fish and aquatic birds were brought in a band for managing it in new pattern. Ecological lessons were hypothesized and validated by results on fishery on lagoons available in literatures. First innovative lesson was that fish adopt site in North East direction of fresh water stream, as also corroborated by honey bee comb sites on N-E side of any circular water tank’s supporting posts. The second innovative fact was to transformed terrestrial land as sites for growing highly palatable nitrogen rich organic feed for fishery. Thus, colonization and feeding become conclusive approach, as supported by past researches, as guide to fishery scientist to move steps ahead in harnessing productivity of lagoons. Thus, fresh and marine brackish water transition zones become vast resources for countries to derive prosperity and employment generations. The innovative fishery feed will be usable for other types of fisheries ie fresh water fishery as well as marine fishery.

Development of racks for maximization of biological harvesting of N and P from sea and marine through aquatic birds producing resource guano

Huge increase of global population was creating stress on terrestrial ecosystems which worry food policy thinkers and planners. Biological nitrogen (N) and phosphorus (P) harvesting was an innovative research development using well accepted and circulated data about seven decades before, which was accepted as innovative way of linking hydro, fishery, aquatic birds, agriculture and environment. This linkage made easy way of opening vast ocean and marine resources harnesssible for extracting organic macro nutrients for agriculture and industrial products. Objective of this study was to develop racks for enabling harvest of the guano. Study facilitated birds social and stochastic and heuristic on inspire design for racks for sitting of aquatic birds and collection of bird droppings in daily routines. The architecture of racks and materials of construction were developed. It was suggested to launch operational research project on harvesting of guano for intended use. Thus new world was created to harness sea resources for innovative product to benefit agriculture, industry and environment by effective use of vast ocean and other existing aquatic systems. This research created new dimension of linking ocean, fish, birds, agriculture, environment and human life easy and reducing stress on terrestrial ecosystems.

Bio-adsorption of methylene blue dye using chitosan-extracted from Fenneropenaeus indicus shrimp shell waste

The cationic dye “Methylene blue” is widely used in textiles industry, pharmaceuticals, paper industries, and ink manufacturing etc, The washed off dyes discharged directly in water bodies and cause major damage to the environment. The molecule of dye is very stable, so that it is very difficult to decompose naturally. Therefore, it is essential to remove the dye by purifying, and prevent the environment from pollution. The –NH2 and -OH functional groups of Chitosan can induce the adsorbing capacity of dyes by its low surface area, porosity and high crystalline nature. Chitosan is an environment friendly, non-toxic, easily available, biodegradable, renewable biopolymer, and harmless to biota. Extraction of chitosan from the “Fenneropenaeus indicus” (Shrimp) shell and its utilization in wastewater treatment controls the environmental problems and contributes to solid waste management. In this study, the possible use of “Fenneropenaeus indicus” (Shrimp) shell chitosan for the bio-adsorption of MB dye was investigated by a batch adsorption method using different adsorbent doses with respect to experimental duration. The maximum amount of dye adsorption was obtained at a minimum dose of 4gram chitosan, with experimental time of 4 hours. The Fenneropenaeus indicus shell chitosan was found to be a better adsorbent since it removes about 93.23% of methylene blue dye from sample water. Further, characterization of functional groups was also done and the changes of groups were observed from both control and treated samples.

Scient metrics analysis of mangrove studies from 1980 to 2020

Mangroves are complex transition ecosystems studied and affected by human activities.. This work sought information on articles in scientific journals related to environmental impacts and their forms of management and restoration and those focused on biodiversity conservation. To answer this question, we developed this work based on a scient metric survey of production with a focus on impacts and environmental and Biodiversity responses on mangroves in the last forty years (1980 to 2020), comparing mainly the global scientific production and the production in America, listing areas of research concentration, and journal, period, country and region of publication of papers. With this survey, we could observe a standardization of the research classification area and publication periods, although checking the journals found a great variety of these. As for the regionalization of studies, we could observe that, globally, the region that most contributes to the advancement in this theme is Asia; however, the country that collaborates the most, in isolation, is the United States. Although there is a diversification regarding the specific theme, the scientific production on mangroves with an environmental focus and in Biodiversity followed a global pattern in the studied period.

Do stranded sand dollars indicate hydrodynamic conditions of sandy beaches?

This article aimed to evaluate sand dollars' distribution (Mellitaquinquiesperforata) by relating it to hydrodynamic variations on Santos Beach (Brazil). Twenty-nine samplings were carried out between March 2015 and July 2018, through 6 transects in the seawater limit, along 5.5km of the beach. The survey of data consisted of two processes: counting and biometrics of the whole individuals present. We noted the wind's direction, the height of the tide, the lunar phase, and the seasons. Canonical Correspondence Analysis and 2way ANOVAs showed that the season, the direction of the prevailing winds, and the moon phase significantly influenced the cookies' spatial distribution, results that coincide with the existing models for erosion and sedimentation. We only registered adult individuals (>4cm). The largest and heaviest individuals occurred in late summer and early autumn (March-April), which suggests that this is the species' breeding season.

An overview of the Anguillid eel culture in Vietnam

The wild eel fishery and eel farming are playing an increasingly important role in aquaculture. Most of the Anguillid eel fries at their glass eel stage are caught in the two provinces of Vietnam, viz., Phu Yen and Binh Dinh, which accounts for over 80% and 10-15%, respectively. The stages of raising eels in Vietnam are very diverse with the survival rate of Anguilla Marmorata is approx. 60% through glass eel and elver stages. The major eel grow-out area of Vietnam is in Mekong delta. Ca Mau province is the highest in eel farming among the 14 provinces in the country. There are over 1,000 eel farms produced about 2,000–5,000 tons of eel in Vietnam at this moment. Around 95% of the total number of farms produced giant mottled eel (A. marmorata), and most of the production (70%) was used for domestic consumption, while30% was exported to the adjacent countries.

Enhancing the supply and self-sufficiency of animal protein for local population through artificial propagation of African sharptooth catfish Clarias gariepinus (Burchell, 1822)

The African sharptooth catfish, Clarias gariepinus Burchell, 1822 is the second most farmed fish species in Senegal due to its high fecundity, good growth performance and tolerance of a wide range environmental condition. Despite its economic importance, much remains to be done to improve the production of the species under controlled conditions. The main objective of this study was to implement a suitable method for seed production to meet the increasing demand for fish through the induction of C. gariepinus spawning by hormonal injection using ovaprim and pituitary gland extracts of C. gariepinus. The experiments were independently conducted in three different locations in Senegal: National Aquaculture Agency (ANA) hatchery (Kolda, Kolda), the National Agency for Agricultural Integration and Development (ANIDA) fish farm (Maraye village, Dagana, Saint-Louis) and SENAQUA farm (Tille Bobou, Khombol, Thiès). The results of hormonal induction with ovaprim (dose: 0.5ml/kg of female body weight) stimulated evolution, with 122,500, 150,000 and 15,000 eggs for the ANA, ANIDA and SENAQUA experiments, respectively. The induction with pituitary gland extracts did not, however, provoke female ovulation, probably due to the low dose of hormone contained in these extracts. The hatching rate of the three localities was 60% (73,500 larvae), 30% (45,000 larvae) and 48% (72,000 larvae), respectively. An average growth of 0.25cm/d was recorded for the ANA larvae that were fed exclusively with zooplankton from the third day after hatching, with an alternation of artificial food and zooplankton on the sixth day and with artificial food only on the fourteenth day. However the larvae in this locality had a very high mortality rate of 95%. The mortality rate was also extremely high at ANIDA (96%) where larvae were fed with artemia the second day after hatching throughout the first week, and at SENAQUA farm (98%) where larvae were exclusively fed with dry artificial food (exogenous) from the third day, which corresponds to the resorption of the yolk sac. The high larval mortalities recorded in this study may be due the diet and/or poor water quality in the rearing tanks. These parameters are crucial for the success of larval breeding of C. gariepinus. Based on these results, we suggest increasing by 2 to 3 pituitaries/female and see the effect of this increase on C. gariepinus ovulation.We therefore recommend monitoring breeding conditions after hatching and feeding the larvae with an appropriate diet, preferentially with live food to obtain a better yield, which could help improve production and open other perspectives for the development of aquaculture in Senegal.