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The freshwater cladoceran Moina micrura has tremendous potential for mass culture as a live feed for larviculture. This study aimed to evaluate the efficacy of probiotics Lysinibacillus fusiformis A1 and Bacillus pocheonensis S2 in enhancing the population density, growth rate, and production of M. micrura under different environmental conditions. Four different temperatures (15, 20, 25, and 30°C), pH levels (4, 6, 8, and 10), and photoperiods (4L:20D, 6L:18D, 8L:16D, and 12L:12D) were set up. The daily number of individuals incubated under each environmental parameter was monitored for 12 days to determine the population density and growth rate of M. micrura. Meanwhile, the daily number of neonates from five females kept under respective environmental parameters was monitored until they died naturally. Probiotics were added individually at 5×104 CFU mL-1 twice during the first and sixth days of the experiment. M. micrura enriched with B. pocheonensis S2 at 30°C had the highest maximum population density (10 ± 0.2 ind mL-1) and the number of neonates produced (132 ± 6.43 ind), whereas treatment at 20°C had the best growth rate (0.1863 ± 0.006 d-1). M. micrura incubated with B. pocheonensis S2 at a normal photoperiod of 12L:12D had the highest maximum population density (10 ± 0.3 ind mL-1) and the number of neonates produced (129 ± 4.58 ind) while incubation at 8L:16D had the best growth rate (0.2879 ± 0.0007 d-1). M. micrura enriched with L. fusiformis A1 at pH 8 had the highest maximum population density (11 ± 0.8 ind mL-1), growth rate (0.5508 ± 0.04 d-1), and the number of neonates produced (129 ± 4.36 ind). Results recommend that a warmer temperature of 30°C, alkaline pH from 8 to 10, and a normal photoperiod of 12L:12D can be adopted for M. micrura enrichment with B. pocheonensis S2 to maximize its productivity for aquaculture use.

Introduction: Food waste has significant economic, environmental and social impacts. The increasing trend of eating habit in urban community has evidence this issues. Henceforth study on food waste management behavioural-attitude in Kuching is imperative. Methods: A questionnaire on sociodemographic characteristics, attitude and behaviour on food waste, as well environmental concerns on food waste were developed. A 407 respondents from Kuching city participated in this study. Results: The results revealed an association between gender and food waste management which included food purchasing behaviour (p-value=0.046) as well as influence of food expiration date on their behaviour (p-value = 0.003), but with very weak r correlations of r (405) = -0.099 and r (405) = 0.149, respectively. There was an association between age and environmental belief in the environmental dimension on food waste (p-value= 0.008) with a weak correlation of r (405) = 0.165. Lastly, education level with purchasing behaviour (p-value= 0.046), food preparation (p-value=0.000) and their environmental concern on food waste (p-value= 0.020) had very weak correlations of r (405) = 0.056, r (405) = -0.047, and r (405) = 0.002, respectively. Majority of the respondents demonstrated feeling responsible when they disposed of avoidable waste even though they intended to prevent such events. Conclusion: Overall, the result had highlighted favourable responses on the relationship between sociodemographic and community food waste generated. This finding could help the policymaker in improving their waste management approaches hence, benefiting the citizen in a whole.

Information on fisheries resources in East Malaysia is scarce and poorly known. The current review aims to compile a checklist of fisheries resources in the Northwest Borneo (Sarawak, Malaysia) from available published literature, address the resources' present status, and suggest future monitoring needs for selected critical species. The study also aims to determine several Sarawak land-use issues that are in flux and responsible for habitat degradation. Five hundred sixty-four species belonging to 123 families and 32 orders were recorded from Sarawak waters. Freshwater fish species comprised 48.0% of the total, followed by a marine (36.6%), marine-euryhaline (12.9%), and brackish water (2.5%) species. Of this, Cyprinidae was the most dominant group accounting for the greatest number of species (82 species), followed by Balitoridae (34 species), Bagridae (21 species) and Penaeidae (21 species). Therefore, available fisheries resources should be managed carefully as 48 species (9.0%) are currently vulnerable to extinction. Furthermore, the presence of 20 alien species in Sarawak water bodies also requires attention from the authorities due to the potential disruption of aquatic ecological balance. Changing land use issues in Sarawak such as forest degradation, agricultural expansion, peatland deforestation and conversion, logging, destruction of mangrove forests, and construction of hydroelectric power dams and flood mitigation channels pose significant challenges to fishery management in Sarawak. Our study documents the priority of fishery monitoring and conservation in Sarawak water bodies to ensure sustainable management of fisheries resources.

In December 2019, a novel coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak was reported for the first time in Wuhan, Hubei province, China. This coronavirus has been referred as Coronavirus Disease 2019 or COVID-19 by World Health Organization (WHO). The spread of COVID-19 has become unstoppable, infecting around 93.5 million people worldwide, with the infections and deaths still increasing. Today, the entire planet has changed due to the greatest threat on the planet since the introduction of this lethal disease. This pandemic has left the world in turmoil and various measures have been taken by many countries including movement control order or lockdown, to slow down or mitigate the infection. Since the lockdown has been implemented almost in all affected countries, there has been a significant reduction in anthropogenic activity, including a reduction in industrial operations, vehicle numbers, and marine-related activities. All of these changes have also led to some unexpected environmental consequences. As a result of this lockdown, it had a positive and negative impact on the environment including the aquatic environment. Hence this review will therefore focus on the good and bad perspectives of the lockdown toward the aquatic environment. © 2021 Penerbit Universiti Kebangsaan Malaysia. All rights reserved.

The interest in the use of mathematical models for the simulation of hydrological processes has largely increased especially in the prediction of runoff. It is the subject of extreme research among engineers and hydrologists. This study attempts to develop a simple conceptual model that reflects the features of the arid environment where the availability of hydrological data is scarce. The model simulates an hourly streamflow hydrograph and the peak flow rate for any given storm. Hourly rainfall, potential evapotranspiration, and streamflow record are the significant input prerequisites for this model. The proposed model applied two (2) different hydrologic routing techniques: the time area curve method (wetted area of the catchment) and the Muskingum method (catchment main channel). The model was calibrated and analyzed based on the data collected from arid catchment in the center of Jordan. The model performance was evaluated via goodness of fit. The simulation of the proposed model fits both (a) observed and simulated streamflow and (b) observed and simulated peak flow rate. The model has the potential to be used for peak discharges’ prediction during a storm period. The modeling approach described in this study has to be tested in additional catchments with appropriate data length in order to attain reliable model parameters.

Zooplankton are primary consumers and serves as a crucial connection between primary producers and consumers in the aquatic food chain and higher consumers. Plankton is consumed by more than 75% of fish species at some point throughout their life. Supply of live feed cultures is critical to the expansion of aquaculture enterprises, particularly the larviculture sector, which generates fish and crustacean seeds for grow-out businesses. However, zooplankton is rarely farmed in high enough densities to be commercially viable on a large scale. This is owing to dynamic changes in physicochemical conditions in the culture system, which would normally result in a shift in the reproduction pathway from parthenogenetic to sexual, which creates resting eggs and reduces overall live feed output. The density of these live feed organisms can alter in response to environmental conditions such as eutrophication due to an excess of nutrients, acidification, pollution, salinity intrusion, and other factors that occur within the system. The water quality and food supply in the system have a big impact on zooplankton population dynamics, especially in a culture environment. The goal of this review is to have a better understanding of the many strategies for growing zooplankton utilizing various fertilization methods in order to maintain a constant population density. This review focusing on the density of zooplankton, the biological responses of live feed to fertilization, and common challenges that farmers face in the culture. In particular, we (i) examine the many zooplankton culture techniques that have been developed over time, (ii) explain the biological reactions of zooplankton to changes in culture conditions, and (iii) show the frequent issues as-sociated with live feed culture.

Artemia is a type of brine shrimp that can provide good nutrients and a well digested fish larva with high potential live feed. Therefore, Artemia is readily contained in capsulated cysts that have been preserved for a long period of time. In the industrial, however, there is a lack of knowledge and technique regarding the handling of suitable life feed as first feed for fish larvae. The study is to observe the growth and survival rate of Angelfish larvae (Pterophyllum scalare) with various types of enriched Artemia. Three types enrichment are used (Tetraselmis sp., Chlorella sp., and mixed diet; Tetraselmis sp. + Chlorella sp.). This experiment was performed for 35 days, and the growth (SGR), survival and nutritional analysis were reported to assess the effect of the larvae of Angelfish. Specific growth rate (SGR) of Angelfish larvae (11.49 ± 0.63%), and survival rate (81.0 ± 1.92%). Angelfish larvae had the highest growth and survival rate on mixed diet fed (Tetraselmis sp. + Chlorella sp.) compared to other enrichments, Tetraselmis sp. (9.56 ± 0.08%, 70.00 ± 0.00%) and sp. (10.03 ± 0.13%, 74.0 ± 2.03%), this was related while examining the protein and lipids. The mean value of the mixed diet protein and lipid analysis (57.91 ± 0.27%, 7.31 ± 1.35%) is the highest as compared to other enrichments, Tetraselmis sp. (44.73 ± 0.73%, 4.85 ± 0.60%), and Chlorella sp. (49.76 ± 1.19%, 7.31± 5.05%). As the conclusion, mixed diet is more successful diet for growth performances and survival rate to fish larvae. This study applies if the Artemia can be culture in the future without the technique of decapsulation cysts to reduce cost in using Artemia.

Marine biodiversity contains various unique life in the sea, from taxa to the ecosystem and provides valuable food sources and ecosystem services to humans and the environment. Climate change impacts towards marine biodiversity and ecosystem services have been done previously by various authors and countries. However, there is limited evidence on its impacts, especially in the form of scientometric study. The current study aimed to give an overview on the impact of climate change towards global marine biodiversity and ecosystem services. A scientometric methodology was implemented using the Web of Science (WoS) Core Collection database for the period from January 1970 to May 2021. Based on articles retrieved from the WoS, we found that the search query retrieved 2161 documents within the research area climate change, marine biodiversity and ecosystem services. A total of 60,051 times cited the total publication (i.e. 2161) with the h-index of 104 (i.e. 104 publications have received a minimum of 104 citations each) and an average of 27.79 citation per article (i.e. item). Research on this area has seen contributions from 3159 organisations worldwide with a huge number of authors involved, 10,319 in total.