Showing papers in "Journal of Aquaculture & Marine Biology in 2017"
TL;DR: Microalgae are common in both industrial and scientific cultivation and have various applications such as a health food, fish feed and nutrition supplements for human consumption, as well as for lipid and biodiesel production.
Abstract: Recently, microalgae are common in both industrial and scientific cultivation. There are different fields of application for microalgae includes food, biofuels, fish feed and pharmaceutical products [1]. Recently, various applications were found for Chlorella vulgaris (C. vulgaris) such as a health food, fish feed and nutrition supplements for human consumption, as well as for lipid and biodiesel production. Algae produced its own food by autotrophic nutrition. The food produced is stored as carbohydrates (mainly as starch) and lipid [2,3].
42 citations
TL;DR: The microalgae has immense application in specific to bioactive compounds derived from algae with proven beneficial and much more effective as compared with traditional treatment methods.
Abstract: Microalgae are a group of unicellular or simple multicellular photosynthetic microorganisms and have been explored for their bioactive compounds and their extracellular products also possess with promising applications encompassing antibacterial, antiviral, antifungal, antialgal antiprotozoal and antiplasmodial activities [1-8]. They are divided into four groups (red, green, brown and blue green). This taxonomic group, not included in Plant kingdom but rather in the Protista kingdom, shows a high photosynthetic performance. So, algae can have a high reproductive potential and therefore can grow very fast. Now, humans can build a shining future to the next generations in different sectors of our daily life using microalgae for very different applications such as energy source, food, fertilizers, nutraceutical, cosmetics, pharmaceuticals, aquaculture purpose and pollution control. The development in algal therapeutic research has made it possible now a days by their bioactive compounds which have been found effective against most of the pathogens [9-17]. The microalgae has immense application in specific to bioactive compounds derived from algae with proven beneficial and much more effective as compared with traditional treatment methods. Fatty acids isolated from Coelastrella spp., R. violacea and Chlorella spp. were found active against human pathogens like S. aureus and low in S. pyogenes [18]. The production of microalgae biomass shows wide valuable uses, in the aquaculture, biotechnology, and food science, among others. However, microalgae show fluctuations in their chemical profile generated mainly by the culture conditions. The previous reports on the assessments of the effect was studied through nitrogen starvation and its totally depends on its growth, nutrient uptake, and gross chemical composition of two species viz. Chlorella spp. and Nannochloropsis oculata [19].
33 citations
24 citations
TL;DR: The data from various sources were critically evaluated at central soil salinity Research Institute, Karnal and figure has now been modified to 7.4 million ha as depicted by the graph below as discussed by the authors.
Abstract: Optimum utilization of available resources has became a necessary due to increasing population pressure in the developing nations. The burgeoning population put thrust on each and every resource to be utilised wisely and sustainably for production of food specially quality protein to feed the population and eradicate malnutrition. Among such underutilised resources, the saline affected land is about 10.1 million ha in India, which suffer from soil salinity problem. However, during the last decade several agencies have given divergent estimates about Indian inland saline area, as National Commission on Agriculture, 7.16 million ha; National Bureau of Soil Survey and Land Use Planning, 6.2 million ha. The data from various sources were critically evaluated at central soil salinity Research Institute, Karnal and figure has now been modified to 7.4 million ha as depicted by the graph below. Since the use of such land and under lying ground saline water is very restricted, so inland saline aquaculture i. e. culture of aquatic animals and plants using inland (Non-coastal) sources of saline ground water are very promising for its sustainable use. Due to non-utilization of ground saline water, the water table in these areas is rising with an alarming rate causing secondary salinization and water logging conditions leading to fertile productive land being gradually unproductive with poor quality water. Pumping of ground saline water therefore is necessary to lower down the water table to a safer root zone so that surface soil remains un-affected with salinity problem providing good soil conditions for adjacent agriculture crops. Pumping of saline water and its safe disposal in landlocked area is a challenging task and possible only through evapo-transpiration, which is a very costly affair; this could be made economically viable through aquaculture practices in which large proportion of water could be evaporated from aquaculture ponds along with production of high income generating fish/prawn/shrimp crops. However, this is not as simple as in coastal waters, since inland saline water is totally different from fresh, brackish and marine water due to unbalanced ionic composition of inland saline water.
15 citations
TL;DR: The effects of the variation in environmental parameters on the behaviour, physiology and cell biology of teleosts are discussed in order to provide useful information for research based on fish models.
Abstract: Over the last few years the increasing use of fish as animal models in scientific research and the increased fish breeding for human consumption have stressed the need for more knowledge on the effect of variations in environmental parameters on fish biology and on the welfare of specimens used both in research and aquaculture contexts. Experimental evidence shows that environmental variations can affect fish biology at various levels, from the molecular to that of the population, sometimes in a different way depending on the species considered. In order to achieve reproducible results in experiments involving fish it is necessary to set and maintain all environmental parameters constant at the optimal value to guarantee the wellness of the animal. The effects of the variation in environmental parameters on the behaviour, physiology and cell biology of teleosts are here discussed in order to provide useful information for research based on fish models.
11 citations
TL;DR: Overcrowding trends adversely affect the health of cultured fish by making them susceptible to infectious diseases, and this research aims to address this problem.
Abstract: Aquaculture production has showed a rapid growth in the last years. To provide increasing amounts of aquaculture for the world’s growing population, many major fish farms are already at maximum capacity; fish are often cultured in limited spaces such as ponds and net cages under high densities, under parameters that depend on the species stocked and prevailing environmental conditions. However, these overcrowding trends adversely affect the health of cultured fish by making them susceptible to infectious diseases [1].
9 citations
TL;DR: Being a dwindling natural resource, dramatic increase of fishing and threats of overcrowded area has been observed and there is a need to protect the natural resources as well as ecology of this site.
Abstract: Badin is famous for swampy deltic land and inconsistent flooding caused by two type of flood, one from melting of ice during summer and other from south west monsoon rain. Due to reducing flow of fresh water and erratic flooding, a person has no dependence on its own water source. The Narrerilagoon is a natural wetland, interconnected with Jabho, Pateji and Cholri wetlands and drain into a tidal link. This intrusion of sea water causes salinity and sedimentation in this lagoon. Being a dwindling natural resource, dramatic increase of fishing and threats of overcrowded area has been observed and there is a need to protect the natural resources as well as ecology of this site. The length weight relationship (LWR) are significantly applied to assess the fish stocks, condition and growth pattern of fish [1]. It also provides the condition of individual fish [2]. Fish condition show the food availability, maturity stages, environmental condition and age and gender.
7 citations
TL;DR: In this paper, the relationship of total shell length between total shell weight was determined as TW = 0.5207* TL 2.4533 (R2= 0.73).
Abstract: In this research, meat yield and shell dimension of smooth scallop (Flexopecten glaber) were specified. 150 individuals of smooth scallop were caught by dredges seasonally in Cardak lagoon on Canakkale strait, Turkey. According to results, the relationship of total shell length between total shell weight was determined as TW = 0.5207* TL 2.4533 (R2= 0.73). Moreover, meat yield of scallop was determined highest as whole meat in spring and as adductor muscle in summer. This paper reveals basic growth data of smooth scallop and its preliminary study for Cardak lagoon which is important bivalve inhabiting area.
7 citations
TL;DR: It is revealed that certain green algae and blue green microalgae having high growth, pH, CO2 fixation, carbon content and biochemical composition paves the way for pharmaceutical activity.
Abstract: The three marine microalgae Chlorella vulgaris Spirulina platensis andNannochloropsis bacillaris were collected from Vellar estuary South east coast of India These three microalgae were cultivated in respective media and estimated their biochemical composition and antibacterial activity Simultaneously these cultures were cultivated in flask containing ml of respective media at lab condition for a period of one month and their growth pH biomass and CO fixation and carbon content were determined Based on the growth rate the pH of three microalgae in media was observed at lab condition During maximum growth and biomass the pH was found to be ranged between amp for Spirulinaplatensis amp for Chlorella vulgaris amp for Nannochloropsis bacillaris Spirulinaplatensis and Chlorellavulgaris reached maximum growth rate whereas Chlorella vulgaris and Spirulina platensis showed maximum biomass produced Chlorella vulgaris and Spirulinaplatensis attained maximum biomass in media at lab condition also fixed highest level of carbon dioxide in media but they did not produce maximum biomass though the growth of Nannochloropsis bacillaris were found high in media at lab condition Among the three microalgae Chlorella vulgaris and Spirulinaplatensis produced highest biochemical compounds Hence Chlorella vulgaris and Spirulinaplatensis were selected as efficient microalgae for antibacterial activity against human pathogen This study revealed that certain green algae and blue green microalgae having high growth pH CO fixation carbon content and biochemical composition paves the way for pharmaceutical activity Antibacterial activity was evaluated for Chlorella and Spirulina withtheir potential health benefits
7 citations
TL;DR: In this paper, the authors proposed that zooplankton contribute importantly to metazoan diversity and production of fish-food organisms in the wetlands but have yet received inadequate attention on their diversity and ecology in the floodplain lakes.
Abstract: The floodplain lakes form an integral component of various riverine systems globally and merit interest for biodiversity and ecology considerations. These remarks hold valid for the Indian floodplains and those of northeast India (NEI) in particular [1-3]. These wetlands form a lucrative source of inland fishery [4] of NEI and are locally known as ‘beels’ in Assam and pats in Manipur. Further, zooplankton contribute importantly to metazoan diversity and production of fish-food organisms in the wetlands but have yet received inadequate attention on their diversity and ecology in the floodplain lakes of India [1] while the related published ecology works from NEI are limited to reports from certain beels of Assam [5-7] and pats of Manipur [8,9].
6 citations
TL;DR: In the Mediterranean non-tide lagoons, microphyte and macroalgae can be very intense (>30 mg chl m-3 and > 10 kg macroalgal mass m-2, for the second) and produce consequences even more serious as a result of their decay, such as drifts of environmental deterioration as mentioned in this paper.
Abstract: In the last forty years, coastal areas have been increasingly subjected to the consequences of eutrophication, which is shown by the opportunistic developments of microphyte and macroalgae [1-3]. Such developments can be very intense (>30 mg chl m-3, for the first, and >10 kg macroalgal mass m-2, for the second) and produce consequences even more serious as a result of their decay, such as drifts of environmental deterioration, which are remarkably evident, above all, in the case of Mediterranean non tidal lagoons. These have poor water exchange by their structural feature, and tend to accumulate energy in the system, mainly in terms of sedimentary organic detritus, as it occurs, e.g., in the lagoons of Prevost [4], Thau [5], Cabras [6], and Orbetello [7]. The remineralization of the bloom after its collapse is conducted mainly by the sulfate reducing bacteria, and produces hypoxic or anoxic conditions and sulphides accumulation, which constitute the final stage of the summer environmental crises of these environments, causing dystrophies, and sometimes die-offs of aquatic fauna [7-9].
TL;DR: In this article, the authors analyse scenario of marine fisheries in India with respect to potential and discuss in detail the Deep-sea fishing, its Prospects, Issues and Challenges in India.
Abstract: Fisheries play a pivotal role in the economic development of all maritime nations. The fisheries sector contributes as foreign exchange earner, ensures nutritional security and generates employment opportunities. With absolute rights on the EEZ, India has also acquired the responsibility to conserve, develop and optimally exploit the marine resources up to 200 nautical miles off our coastline [1]. The current exploitation from the marine capture sector is 3.44 million tonnes in 2013-14 as against the potential of 4.41 million tonnes. Indian marine fish harvest mostly centers around coastal waters up to 100 m depth and about 90 per cent of the catch comes from up to 50 m. A recent revalidation of marine fisheries potential has shown that the fishing pressure on the stock in near shore waters has gone up considerably and signs of over exploitation of species is becoming increasingly evident and further increase in effort in the coastal sector would be detrimental to sustainable yield. In case of India, the total production for Yellowfin tuna has fluctuated from 7544 tonnes in 2011 to 22, 155 tonnes in 2008. However, in case of Skipjack tuna, production has declined from 18934 in 2011 to 7212 tonnes in 2012. In other words, India is presently harvesting about 12 % of the potential and the balance can be optimally harvested using a judicious mix of technology, infrastructure and human resource development. As the coastal fishery faces issues like the sustainability, resources conservation and management; there is an imperative need for finding an alternative resource for the nutritional security. Exploitation of under exploited non-conventional resources from the distant waters of the Indian EEZ will be the only solution. There is ample scope of increasing production by venturing into deeper waters of the EEZ, which holds a potential of 1.7 million tonnes of underexploited and unexploited fin fishes and shellfishes. This indicates there is an ample scope for development of this sector. In this context, the aim of the present study was to analyse scenario of marine fisheries in India with respect to potential and discuss in detail the Deep-sea fishing, its Prospects, Issues and Challenges in India.
TL;DR: According to the Convention on Biological Diversity (CBD), there is a need for "compilation and dissemination of information on alien species that threaten ecosystem, habitats, or species, to be used in the context of any prevention, introduction and mitigation activities" as mentioned in this paper.
Abstract: Submit Manuscript | http://medcraveonline.com invasive species to agriculture and forestry in India is to the tune of 91 billion dollar a year Hiremath & Krishnan [2]. The magnitude of invasions may be apparently local, but the drivers of bio-invasion are global. According to the Convention on Biological Diversity (CBD), there is a need for “compilation and dissemination of information on alien species that threaten ecosystem, habitats, or species, to be used in the context of any prevention, introduction and mitigation activities (CBD, 2000)”.
TL;DR: In this article, a brief discussion in collision and grounding for related objects in scopes of marine structure and ocean engineering is presented, where several examples are addressed to observe contribution this part in history of naval architecture.
Abstract: Various activities are conducted in oceanic territory in order to fulfil numerous demands. Ship has important role in these activities as transportation, supplier, and vessel which also directly connects with marine structures, such as offshore platform. Complex function of each facilities in this field makes chain reaction of one event can be remarkable and fatal. Accidental load becomes major consideration in operation of these marine and ocean facilities with famous example of accident phenomenon Titanic and Exxon Valdez have made related parties to perform sustainable analysis to develop assessment method, refine formula, propose prevention system, mitigation scheme, structural behavior, etc. In present work, a brief discussion in collision and grounding for related objects in scopes of marine structure and ocean engineering. The introduction is presented in initial part as presenting background, importance, and implication of impact engineering. Several examples are addressed to observe contribution this part in history of naval architecture. In next section, discussion is given in specific fields, namely ocean and marine engineering. Implementation of impact and accidental load are presented in conceptual method and material preparation. Results are described as milestone of collision and groundings’ development. In later section, conclusion is summarized based on discussion and recommendation in performing analysis and calculation for collision and grounding are covered.
TL;DR: It is demonstrated that 10% sesame seed meal and peanut meal could be used in diets of rainbow trout without any negative effects on growth and showed that using these protein sources together may provide better results rather than using them alone.
Abstract: This study was conducted to evaluate the partial replacement of soybean meal by sesame seed and peanut meals in practical diets for rainbow trout (Oncorhynchus mykiss). Four isonitrogenous (44% protein) and isolipidic (19% lipid) diets were formulated. The trial diets were prepared to include 10% sesame seed meal (S10), 10% peanut meal (P10), 5% sesame seed meal+5% peanut meal mix (SP10) and a control (C) with no replacement of soybean meal. There were four dietary treatments, with three replicates for each treatment. The fish (initial average weight; 79.86±0.14 g) were hand-fed twice a day to apparent satiety under a natural light regime for 65 days. At the end of experiment, the best growth was determined in SP10 group (p<0.05). The growth performance of S10 and P10 groups was significantly lower than control and SP10 groups (p<0.05). The hepatosomatic index (HSI) and viscerosomatic index (VSI) values were not affected from the protein sources in the diets (p>0.05). Comparing to the initial sample, the moisture, protein, lipid and ash contents in the body composition of the fish increased in all experimental groups and were not significantly differed among the groups (p>0.05). In the crude protein digestibility was no differences in among groups (p>0.05), but the highest apparent protein digestibility coefficients were determined for C (91.26%) and SP10 (91.93%) groups. The present results demonstrated that 10% sesame seed meal and peanut meal could be used in diets of rainbow trout without any negative effects on growth. The results showed that using these protein sources together may provide better results rather than using them alone.
TL;DR: In this article, an experiment was conducted to provide an estimate of the shelf life of thicknesses of gravlax salmon stored at deg C by monitoring pH water activity and salt levels over a day period and microbial numbers TPC over days.
Abstract: Gravlax Atlantic salmon is a raw fish product typically stored at chill temperatures that will go through no further heat processing before consumption Bacterial spoilage can reduce shelf life while pathogens can represent a serious hazard for susceptible consumers This experiment was conducted to provide an estimate of the shelf life of thicknesses of gravlax salmon stored at deg C by monitoring pH water activity aw salt levels over a day period and microbial numbers TPC over days Total plate counts for both the cm and cm thicknesses remained at less than CFU g at the conclusion of the experiment on day Salt levels were and and water activity values and for and cm thicknesses respectively From these figures it was concluded that both the cm and cm thicknesses of gravlax treated Atlantic salmon stored at deg C have shelf lives longer than days
TL;DR: This research was done based on the author s curiosity to know how sustained the performance of Dodola island during the time the island had declared as a virgin beach Moreover Ministry of Tourism collaborated with the Government of Morotai District launched the program Wonderful Moroti Island Through their program rsquo s aims to increase the number of tourists visiting the area The program combined the natural marine cultural and artificial attractions.
Abstract: This research was done based on the author s curiosity to know how sustained the performance of Dodola island During the time the island had declared as a virgin beach Moreover Ministry of Tourism collaborated with the Government of Morotai District launched the program Wonderful Morotai Island Through their program rsquo s aims to increase the number of tourists visiting the area The program combined the natural marine cultural and artificial attractions This study conducted based on the concept of coastal tourism in a sustainable manner The concept was very realistic to be implement on improving their performance to build coastal ecotourism in the area that has a very limited number of human resources funding and time This study had conducted for a year with quantitative and qualitative mixed mode research The questionnaires distributed purposively and tabulated using content analysis The results of the study showed that in addition to coastal tourism facilities and infrastructure it was also necessary to socialize with all stakeholders on technology and coastal tourism development in a sustainable manner This collaboration had improved the performance of coastal tourism on the island
TL;DR: The present preliminary study attempted to evaluate the genetic variation in morphologically similar species of genus Thalamita by the use of electrophoresis and revealed that the genetic diversity was highest in T. danae as compared to T. crenata and the lowest inT.
Abstract: The genus Thalamita ofthe family Portunidae distributed in intertidal zone especially in rocky shore They are important to economically because fishermen can take their meat to sell at high price and also used as bait Due to the privation scientific information and no work has been done on these species especially from a biochemical and genetic perspective consequently the present preliminary study attempted to evaluate the genetic variation in morphologically similar species of genus Thalamita by the use of electrophoresis Isozyme variations were determined in four Thalamita spp and seven enzyme system was selected the study was revealed that the genetic diversity was highest in T danae as compared to T admete and T crenata and the lowest in T savignyi Genetic identity and genetic distance were also observed to evaluate the relationship between species This selective information will be helpful to assess the status of the species and provides basic data for further studies
TL;DR: The morphological characteristics of Lutjanus notatus have been described and added to the Indian Ichthyofauna.
Abstract: The rare blue striped snapper Lutjanus notatus (Cuvier, 1828) (Lutjanidae) is a reef fish found relatively large distribution around the western Indian Ocean. It is harvested as a food source, but is not a commercial species [1]. Rare blue striped snapper belongs to the fishes of the family Lutjanidae. This is one of the largest families in the order perciformes and comprises 4 subfamilies, 17 genera and 110 species, mainly found on coral reefs in tropical and subtropical regions of the Atlantic and Indo-Pacific [2,3]. The largest subfamily is Lutjaninae with six genera Hoplopagrus, Lutjanus, Macolor, Ocyurus, Pinjalo and Rhomboplites with about 72 species. The genus Lutjanus has about 64 species [4,5]. Here we described the morphological characteristics of Lutjanus notatus have added them to the Indian Ichthyofauna. Previously many reports were recorded from Mainland of India. New record of low fin scorpion fish Scorpaenodes parvipinnis from Indian waters [6] first time recorded of Rama Rao’s scorpion fish, Scorpaenopsis ramaraoi from Andhra Pradesh Coast [7] First record of golden barred butterfly fish Roa Jayakari from Visakhapatnam coast [8], first record of spiny snout squirrel fish Middle East coast of India [9], rare sharp tail mola Masturus lanceolatus recorded from coastal waters of Visakhapatnam [10].
TL;DR: In this article, the taxonomic characteristics and distribution of Gulf Smooth Hound (Triakidae) and Bigeye Sixgill sharks (Hexanchidae) based on the examination of three specimens from the Gulf of Mexico were presented.
Abstract: In this study, we present information regarding the taxonomic characteristics and distribution of Gulf Smooth hound (Triakidae) and Bigeye Sixgill sharks (Hexanchidae) based on the examination of three specimens from the Gulf of Mexico. While both species are distributed in the area, very few are included in reference collections [3,4] this is due to the rarity of capturing them and the difficulty of curating such large samples.
TL;DR: The diatom T. weissflogii (size 6-15μm x 20 μm) is used as food for shrimp and in the production of bivalve larvae and is considered by several hatcheries to be the best for growing shrimp larvae since it is a rich source of eicosapentaenoic acid (EPA) and docosahexaenoic Acid DHA, essentials for growth and development of marine organisms.
Abstract: Rotifers are a useful source of food in aquaculture [1]. Their nutritional content is enhanced if they are fed on algae, particularly in terms of vitamins and essential fattyacids. The algal genera most frequently used for this purpose are Chaetoceros, Thalassiosira, Isochrysis, Nannochloropsis and Tetraselmis [2]. The diatom T. weissflogii (size 6-15μm x 20 μm) is used as food for shrimp and in the production of bivalve larvae. This alga is considered by several hatcheries to be the best for growing shrimp larvae since it is a rich source of eicosapentaenoic acid (EPA) and docosahexaenoic acid DHA, essentials for growth and development of marine organisms [3-6].
TL;DR: Seagrasses are a relatively small group of submerged flowering plants of approximately 72 species, representing less than 0.1% of the angiosperm taxa growing in shallow coasts of the tropical and subtropical regions.
Abstract: Seagrasses are a relatively small group of submerged flowering plants of approximately 72 species, representing less than 0.1% of the angiosperm taxa growing in shallow coasts of the tropical and subtropical regions. However, about 60% of seagrass meadows globally have been seen reductions in their distribution since 1980 [1,2]. The ecological importance of seagrass beds has been well documented and includes the provision of sheltered habitats and crucial feeding, spawning and nursery grounds for economically important species of marine invertebrates and fish species [37]. Furthermore they are key primary producers, involved in epibenthic and benthic production; provide important nutrients and contaminant filtration, producers of oxygen, recycles of nutrients [8]. However, since 1980 about 60% of seagrass populations globally have seen a reduction in their distribution due to habitat destruction and marine pollution [1,2].
TL;DR: The methods for developing and analyzing System Behavior Charts are applied to two longitudinal datasets from coastal, estuary and freshwater conservation, threatened species head-starting (sea turtles), and mortality of aquatic mammals (manatees) due to human waterway traffic (watercraft collisions).
Abstract: Conservation practitioners need to predict changes in ecological performance, such as species population levels, and the status of threats. Whilst an assessment of ecosystem status can be achieved from complex data analyses, this is less helpful for practical decision-making on the ground where a straightforward, reliable decision-framework is required. Systems Behavior Charts offer a simpler method for reviewing the state of the system. The methods for developing and analyzing System Behavior Charts are applied to two longitudinal datasets from coastal, estuary and freshwater conservation, threatened species head-starting (sea turtles), and mortality of aquatic mammals (manatees) due to human waterway traffic (watercraft collisions). Inferences from observations are made using a series of empirical rules. Results illustrate how Systems Behavior Charts identify changes, declines, recoveries and steady state systems. This insight enables early intervention, identification of actual improvements in ecosystem performance. These insights illustrate how Systems Behavior Charts offer an improved approach to analyzing data sets to support marine and aquatic conservation.
TL;DR: Economic data are only available within EU countries, which mean around the 50% of total Mediterranean production, with 149 thousand tons and 1009 million USD, where gross Value Added was positive in the whole period 2009-2013, but negative in 2014.
Abstract: Economic data are only available within EU countries, which mean around the 50% of total Mediterranean production, with 149 thousand tons and 1009 million USD (JRC, 2016). Gross Value Added (GVA) was positive in the whole period 2009-2013, but negative in 2014, moreover Net Profit Margin (NPM) was negative in all period except in 2011 and 2012 (Figure 2). This situation is partially due to low sales price of both species, around 6.36 USD/kg, because in most cases total operating costs are higher than total income (JRC, 2016). Nevertheless, price is difficult for farmers to control, so the other possibility to improve profit would be to reduce operative costs through an improvement of management of biomass stock and feeding.
TL;DR: Two respirometer tests performed in order to improve the financial stipulations and reduce the economic risk in a critical stage of development of lobster aquaculture are described.
Abstract: The existing information on the metabolism in European lobster (Homarus gammarus) is sparse. However, dimensioning of intensive systems for commercial production of lobster in recirculating aquaculture systems (RAS) requires adequate information in order to optimise financial calculations and profit margins. Thus, a lack of available data, especially regarding oxygen consumption and ammonia excretion, hampers development and commercialisation of lobster aquaculture. During 2010 and 2013, respiration and excretion rates in juvenile lobsters ranging from 0.06 to 208 g were recorded in a respirometer. These tests aimed to obtain data of standard metabolism in lobster at normal activity and optimum temperature (20 ±1°C). The metabolic rate in fed juveniles < 2 g varied from 1.2 to 14.3 mg O2/kg min. In the larger juveniles and adults, the metabolic rate was less variable ranging from 1.1 to 3.1 mg O2/kg min. The respiration rate in unfed lobsters was relatively stable, varying from 0.8 to 2.4 mg O2/kg min. The excretion rate was likewise larger in the smaller juveniles with a mean of 0.51 mg TAN/kg/min compared with the largest individuals of 0.07. This article briefly describes the two respirometer tests performed in order to improve the financial stipulations and reduce the economic risk in a critical stage of development.
TL;DR: Moreno-Casasola et al. as discussed by the authors showed that if mangroves are cut down, the lagoons productivity is impoverished; changes the rivers mouths modify the hydrology and alter the exchange and amount of water and their quality, sediments and organisms entering and leaving the lacustrine environment.
Abstract: Mexican coastal lagoon systems, or wetlands, have a complex interaction with various environmental factors which makes them more vulnerable because, when the balance of the environmental framework is disturbed, the impact on the ecosystem is immediately felt. According to Moreno-Casasola [1], if sediments are deposited in wetlands and salt marshes, subsidence (submersion) occurs. If mangroves are cut down, the lagoons ́ productivity is impoverished; changes the rivers mouths modify the hydrology and alter the exchange and amount of water and their quality, sediments and organisms entering and leaving the lacustrine environment. When anthropogenic economic activities increase in a disorganized way, as is the case with any hydraulic infrastructure, not only the functioning of the ecosystem must be considered, but also their medium term repercussions.