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Governments at all levels in China have developed a number of policies to guide, bolster and manage the offshore cage aquaculture since the introduction of this industry in the late 1990s. In this study, the evolution of 69 such policy documents issued since 1999 is traced out for the first time. Two time periods can be distinguished in offshore cage aquaculture in China: the Local development period (1999–2010) and the National development period (2011-present). The performance of the policy goals and objectives, the policy issuers, and the policy content are then examined through a combination of qualitative and quantitative analysis in order to figure out how the offshore cage aquaculture development philosophy has transformed, including its developmental ideas, directions, and focuses, all of which are manifested in the policy text. Under the guidance of the concept of sustainable development, the offshore cage aquaculture will play a more important role in the marine economy and impose new requirements on its policy environment in the future. Therefore, the formulation and implementation of policies have to be continuously improved to adapt to the development of offshore cage aquaculture. The following corresponding outlooks are proposed: (1) to expand the participation of formal policies with higher effectiveness, so as to secure long-term guidance; (2) to facilitate the involvement and communication of stakeholders; and (3) to improve relevant procedures and quantify the objectives, so as to better adhere to the goal of sustainable development. [ABSTRACT FROM AUTHOR]

Industrialized aquaculture is an essential trend for aquaculture development in China, owing to its considerable advantages in lower water consumption, higher productivity, and sustainability. However, information on its current status has been scarce up to now. This paper reviewed the current status and has identified existing problems as well as proposing possible solutions for the development of industrialized aquaculture in China. This field is still at an early stage of development and is mainly distributed in coastal regions. Major constraints on industrialized aquaculture include high capital and operational costs, the uncompetitive market price of aquatic products, uneven distribution of production and farming areas, a lack of suitably experienced managers and operators for recirculating aquaculture systems, and the coronavirus disease 2019 (COVID-19) pandemic. Possible solutions to these problems include technological innovations in systems optimization, the use of renewable energy sources and biofloc technology, the pollution-free certification of industrial aquaculture products, increased numbers of professionals in water quality control and waste management, and the financial assistance to companies and farmers along the aquaculture industrial chain. [ABSTRACT FROM AUTHOR]

The giant river prawn, Macrobrachium rosenbergii, is a major focus of aquaculture in tropical and sub‐tropical regions around the globe. Over the last 30 years, culture of M. rosenbergii has increased exponentially as demand has risen both for domestic consumption and for international export trade. As with many aquaculture species increases in production have been accompanied by the emergence of diseases affecting yield, profit and trading potential. Disease‐causing agents include pathogens infecting other crustaceans, such as Decapod Iridescent Virus (DIV1), as well as pathogens only known from M. rosenbergii such as White Tail Disease caused by Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV). Here, we review the pathogenic agents associated with the culture of M. rosenbergii since commercial culture began in earnest during the 1970s. Particular emphasis is given to pathogens first identified in other aquaculture host species, but which have subsequently been shown to infect and cause disease in M. rosenbergii. As polyculture of M. rosenbergii with other aquaculture species is common practice, including culture with other decapods, crabs and fish, increased pathogen transfer among these farmed species may occur as M. rosenbergii aquaculture increases in the future. [ABSTRACT FROM AUTHOR]

The purpose of this study is to explore the adoption of innovation in the aquaculture sector through the Awareness Knowledge Adoption Implementation Effectiveness (AKAIE) sequence. The AKAIE is an extension of the Awareness Knowledge Adoption Product (AKAP) model in order to better investigate the post‐adoption phases. Using the 'Implementation' and 'Effectiveness' phases, this study aims to further the understanding of both the different levels of adoption and the impact of innovation in terms of environmental, economic and social benefits produced. The proposed sequence is contextualised in light of the multidimensional scenario of on‐farm and off‐farm factors acting alongside the adoption of new technologies in the aquaculture sector. In this paper, the perspective of aquaculturists is represented with the concept of perceived complexity as the central node of the adoption process. The proposed tool could support policy makers in understanding and disseminating innovation in aquaculture. [ABSTRACT FROM AUTHOR]

Despite the fact that Nile tilapia (Oreochromis niloticus) (Linnaeus, 1758) are African freshwater fish, they have been introduced into many countries inside and outside Africa. The journey of Nile tilapia started during the second half of the 20th Century, especially in Southeast Asia and the Americas, mainly for aquaculture and fisheries enhancement. Most of these introductions became well established in aquaculture. As a result, aquaculture of Nile tilapia has been steadily expanding in many countries. These fish play an important role in the livelihoods of local societies on different continents. This review summarizes the current knowledge on global Nile tilapia introductions and sheds light on their social and economic contributions to the countries into which they have been introduced, as well as their share in the global fish market. The ecological impacts of tilapia introductions have also been addressed. The success stories of the major Nile tilapia producers were highlighted so that the lessons learned from their experiences could be transferred to other countries. [ABSTRACT FROM AUTHOR]

Adsorption has been considered as a promising remediation technology to separate organic and inorganic agrochemicals from contaminated soil and water. Low-cost adsorbents, including waste derived materials, clay composites, biochar, and biochar modified materials, have attracted enormous attention for the removal of organic contaminants, including pesticides. In this study, iron-modified base-activated biochar (FeBBC) was prepared by pyrolysis (at 400 °C for 1 h) of iron-doped base (KOH) activated sugarcane bagasse for the removal of a widely used insecticide, namely imidacloprid (IMI) from water. The maximum adsorption capacity of the adsorbent (FeBBC) was calculated as 10.33 (± 1.57) mg/g from Langmuir isotherm model. The adsorbents could remove up to ~ 92% of IMI from aqueous solution at 23.8 mg/L IMI. Experimental data fitted well with the Freundlich model and pseudo-second-order model, demonstrating physisorption, as well as chemosorption, contributed to the sorption process. Even at highly acidic/basic solution pH, the FeBBC could remove substantial amount of IMI demonstrating hydrophobic interaction and pore diffusion play vital role for removal of IMI. The slight improving of IMI sorption with increasing solution pH indicated the sorption was also facilitated through ionic interaction alongside physical sorption. However, physical sorption including hydrophobic interaction and pore-filling interaction plays a vital role in the sorption of IMI. [ABSTRACT FROM AUTHOR]

Copyright of Jurnal Akuakultur Indonesia is the property of IPB University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Imidacloprid is a systemic insecticide that belongs to the neonicotinoid class of chemicals that act on the central nervous system of insects. Imidacloprid is used to control sucking insects, chewing insects such as termites, soil insects, and fleas on pets, as well as to treat structures, crops, soil, and seeds. As a result of these factors, this pesticide may end up in the aquatic environment via municipal discharges and runoff. Although the presence of imidacloprid in aquatic environments has been underreported as widespread, the toxic effects of this pesticide may have serious implications on aquatic organisms, particularly at environmentally relevant concentrations and demand more attention. Given this knowledge, the goal of this study was to investigate the effects of imidacloprid on Clarias gariepinus embryonic development. Clarias gariepinus embryos (3 h post-fertilization) were exposed to environmentally relevant concentrations of imidacloprid (10, 30, 100, and 500 µg/L) until 48 h post-fertilization using a modified fish embryo acute toxicity test (OECD TG 236). A stereomicroscope was used to assess hatchability, deformity, heart rate, and swimming speed as endpoints. According to our results of the developmental acute toxicity test, imidacloprid significantly reduced the hatching rate and heartbeats of C. gariepinus embryos. It also influenced the swimming kinematics of exposed embryos and caused teratogenic effects such as yolk sac rupture, pericardial oedema, lordosis, an abnormally shaped head, and altered epiboly. Our results allow us to conclude that imidacloprid is a toxic pesticide in the early life stages of C. gariepinus due to its high teratogenic potential. [ABSTRACT FROM AUTHOR]

Global warming and pesticide contamination are two stressors of high concern, but their combined effects on freshwater biota are controversial. This study investigated the combined effects of warming and imidacloprid (IMI) on survival (measured as life expectancy at hatching), reproduction (net reproductive rate), population growth (intrinsic rate of population increase) and sexual reproduction (proportion of sexual offspring) of Brachionus calyciflorus using a life table experiment. The results showed that compared with controls, treatments with IMI at 50–100 mg/L significantly decreased survival, reproduction and population growth of the rotifers at 20℃. The inhibiting effect at higher IMI concentrations on survival increased with increasing temperatures, but those on reproduction and population growth increased only when the temperature increased from 25℃ to 30℃. The proportion of sexual offspring decreased with increasing temperatures. When monitoring the ecological effects of pollutants, environmental temperature and the possible adaptation of rotifers to it should be taken into consideration. [ABSTRACT FROM AUTHOR]

Aquaponics, a combination of aquaculture and hydroponics, is a potential solution for the consequences of global warming and eventual food meagreness. Aquaponics is known to be an efficient method to deal with the wastewater problem associated with aquaculture and nutrient management issues in the hydroponic discipline. However, optimizing the process condition for aquaponics is frequently ambiguous and is often not economically feasible. Farmers face many constraints in maintaining the process. The main reason for this could be the limited scientific knowledge of various aspects of aquaponics. Through this review, we would like to put a limelight on various critical concerns that could be problematic to beginners in aquaponic farming. These could be from choosing the appropriate design of the system to thriving plants free of diseases. Henceforth, we identified research opportunities that have the potential to fill scientific gaps in this field. Our findings suggest that aquaponics could emerge as the future of agriculture if the discussed challenges are addressed appropriately. [ABSTRACT FROM AUTHOR]

Due to urbanization and industrialization, water pollution is now one of the major environmental challenges of the twenty-first century. Considering the increasing of agricultural and non-agricultural settings in the last decades, the investigation of the relationship between such pesticides and urban stormwater is critical to understand how urban, residential, and industrialized areas can affect environmental safety. Recently, scientific interest has grown in stormwater chemical characterization with the aim to define its impacts in the environment and possibly to make it potable water. In this context, glyphosate, glufosinate, and their degradation products have been identified as the key knowledge gap for the chemical characterization of stormwater. Research investments are needed for a better understanding of the highly polar pesticides to estimate their load, source, and dispersion of urban runoff due to residential use of herbicides. Furthermore, a more comprehensive study of wet and dry deposition and spray drift should be considered for a correct evaluation of source apportionment. [ABSTRACT FROM AUTHOR]

Delta ecosystems are vulnerable to climate change from rising temperatures and altered rainfall patterns, as well as further threats from salinity and erosion due to coastline exposure. Smallholder farmers in deltas are adapting to these risks through cropping systems intensification and diversification, but it is unclear which cropping options offer better profitability and less risk and what transformational support is needed. Using qualitative and quantitative primary field data from southwest coastal Bangladesh, this research analysed risk perceptions and adaptation responses and evaluated the profitability of seven cropping systems. Rainfall anomalies, extreme weather events, and seasonal price fluctuations were core risks for farmers. Risk management strategies included adjusting sowing/transplanting dates, changing crop cultivars, increasing chemical applications, storing irrigation water, and seeking market updates. The dominant systems (rice/rice/fallow, rice/fallow/fallow) had the lowest profitability, while systems with vegetables had the highest profitability. The risk analysis estimated that the dominant systems would incur losses every three years and rice/watermelon/fallow every eight years, but vegetable- or jute-based systems' risk was negligible. However, expanding vegetable-based systems is constrained by higher input costs, lack of capital, labour-intensive practices, market access, and persistent environmental risks. Therefore, multiple strategies are required by public and commercial actors at multiple levels to support smallholders to promote sustainable trade-offs between diverse risks, short-term profitability, and sustainable managing labour, capital, and inputs. The findings highlight the need for agricultural policies and intervention programs to address production technologies, market access, financial services, and extension and training for production and agribusiness skills. [ABSTRACT FROM AUTHOR]

Pesticides applied worldwide to meet food demand is recognized as a key threat to the Sustainable Development Goals (SDGs) set by the United Nations. Studies on pesticide risks employ different ingredients, methods or specific environments, which makes it difficult to quantify the scale of the problem. Furthermore, the complex influences and hotspots of long-term pesticide usage remain unclear. Herein, we present a national-scale study of four typical pesticides in China, the world's largest pesticide user. The spatiotemporal changes in legacy and risk of pesticides over 30 years were analyzed using a modified fugacity model approach coupled with comprehensive ingredient database. Pesticide risk in mainland China might last until 2075 due to the previous legacy, although the usage has declined since 2014. The use of target pesticides was estimated as 2.38 × 105 tonnes in 2017, and about 6.59 × 103 tonnes discharged into the ocean from major basins. Risk areas expanded from 47% in 1991 to 79% in 2017, with 30% at high risk. Of the risk areas, 31% were highly populated while 3% had high biodiversity. 7% of mainland China suffered from both limited water resource and high pesticide risk. It is shown that the improper substitution with lower toxicity pesticides would make the proportion of high-risk regions unexpectedly increased from 18% to 44% due to the longer half-lives of the alternatives. Pesticides pose risks to environmental and human health, and the tailored assessment tool will be vital in contributing towards future pesticide management and meeting sustainability targets in China. [ABSTRACT FROM AUTHOR]

In chemical risk assessment, extrapolations from laboratory tests to more realistic conditions are essential to address the toxic effects of pesticides on individuals and populations under field conditions. To transfer toxicological laboratory tests to differing temperature conditions, or outdoor field scenarios, the consideration of temperature dependence is essential and increases realism. Special consideration is given to the impact of temperature on direct sensitivity of organisms to pesticides, for which there are only few modelling approaches available so far. We present a concept for applying physiological temperature dependencies to toxicokinetic–toxicodynamic (TKTD) parameters in the General Uniformed Threshold model of Survival (GUTS). To test this approach in an exemplary study, temperature dependencies from studies on the developmental rate of the mayfly Cloeon dipterum were applied to the parameters of a previously parameterised TKTD model of this species after exposure to imidacloprid. Using a physiologically derived temperature correction for the TKTD rate constants, model predictions for independently conducted toxicology experiments with temperature ranges between 7.8 and 26.4 °C were performed for validation. Our approach demonstrates the successful transfer of a physiological observed temperature dependency on toxicity parameters and survival patterns for Cloeon dipterum and imidacloprid as a case study. [ABSTRACT FROM AUTHOR]

Imidacloprid (IMI) is a neonicotinoid insecticide widely used in agriculture worldwide. This pesticide has been found in freshwater ecosystems, including Brazilian freshwaters. For this reason, studies are being conducted to detect the presence of IMI in freshwater and understand its effects on the aquatic biota. In the present study, the acute toxic effect of the imidacloprid commercial formulation (ICF) Galeão® on the Brazilian non-target aquatic organisms Chironomus sancticaroli and Poecilia reticulata was evaluated. Enzymatic activities (glutathione S-transferase (GST), catalase (CAT), and ascorbate peroxidase (APX)) were also determined. Moreover, we considered 11 studies that detected IMI concentrations up to 3.65 µg.L−1 in 28 different Brazilian freshwaters to evaluate the acute ecological risk of IMI in these environments. From the ecotoxicological assays, we determined the LC50 values for C. sancticaroli (LC50-48 h 1.52 µg.L−1) and P. reticulata (LC50-96 h 122.65 mg.L−1). The high sensitivity of C. sancticaroli demonstrates that this species could be used as a bioindicator in studies investigating the contamination of freshwater by IMI. Enzymatic activity changes were observed in both organisms and offered sublethal responses to the effects of the pollution by IMI on aquatic biota. Our results suggest that the presence of IMI in Brazilian aquatic ecosystems can represent a potential ecological risk for the aquatic insect populations and, consequently, cause an imbalance in these ecosystems. The present study provides relevant and comparable toxicity information that may be useful to develop public policies to protect the Brazilian aquatic ecosystem from IMI contamination. [ABSTRACT FROM AUTHOR]

This article assesses strategies for managing the economic returns to an aquaponics production system with joint products of lettuce and tilapia. Experimental data from Brazil that varied fish stocking density and the fish feeding rate are analyzed using nonparametric efficiency testing methods to identify potentially profitable technologies and their sensitivities to prices of inputs and outputs. Plants and fish production are symbiotic in an aquaponics system, with fish waste providing nutrients for plant growth and plants helping maintain water quality for the fish via filtration. The optimal input/output mix among alternatives is identified, and sensitivity analysis is used to assess the price ranges around recent market conditions (0.18 R$/tilapia fingerling, 2.8 R$/kg for fish feed, 20 R$/kg for juvenile fish, and 1.57 R$/kg for lettuce) over which that technology choice remains optimal. The configuration of production controls is robust to price changes. Results show that at low fish stocking densities (100 fish/m3), the effluent in the water provides insufficient nutrients to plants. In addition, early lettuce harvests (before 26 days) are generally less efficient than treatments that allow more time for plant growth. Sensitivity analysis indicates that the optimality of the identified configuration of production controls is robust with respect to input and output prices. [ABSTRACT FROM AUTHOR]

This study evaluated the combined use of the brown seaweeds Sargassum filipendula (S) and Undaria pinnatifida (U) dry biomass as feed additive for Pacific white shrimp reared in biofloc system, and its effect on shrimp performance, gut microbiota, hemato-immunological parameters, resistance to acute thermal stress and challenge with White Spot Syndrome Virus (WSSV) associated with thermal fluctuation. Prior to stocking, it filled each tank with water from a biofloc matrix tank (160 L) + seawater (240 L, salinity: 33 g L−1), then stocked with 300 shrimp m−3 (~ 3.8 g). During the experiment (five weeks), shrimp were fed three diets: without (control) and with 1%:2% and 1%:4% (S:U) of seaweed addition (all in quadruplicate); and alkalinity was maintained above 150 mg L−1 with calcium hydroxide and solids between 400–600 mg L−1 using clarifiers. No significant differences were found in survival, feed conversion ratio, and growth among treatments. Shrimp from 1S:2U treatment showed the highest gut bacterial diversity. Additionally, animals from seaweed-fed treatments, especially 1S:2U, displayed lower abundance of Vibrionaceae and higher of Flavobacteriaceae compared to control. Only shrimp from 1S:4U treatment showed higher hemato-immunological parameters (except total hemocyte count) than control. Animals from 1S:2U had lower cumulative mortality (27%) than 1S: 4U (48%) and control (50%) after acute thermal stress. Meanwhile, shrimp from 1S:2U (26%) and 1S:2U (34%) showed lower cumulative mortality after WSSV challenge + thermal fluctuation than control (68%). Therefore, the dietary addition of both brown seaweeds caused beneficial physiological effects for L. vannamei without impairing its performance. [ABSTRACT FROM AUTHOR]

A marked increase in food production is necessary if the World Health Assembly goal of ending world hunger and malnutrition in all its forms by 2030 is to be achieved. To this end, aquaculture plays a major role, but it could play an even more prominent role at least in some areas, especially Africa. There is a need to further develop aquaculture because harvesting from natural populations of potential food-species is not sustainable. At the same time aquaculture may also have some negative environmental and public health effects. Environmental effects are primarily due to eutrophication of natural habitats. Negative health effects are related to the potential presence of chemical residuals (medicine residuals or heavy metals from feed), pathogens or parasites in the final product. In Africa, there is a special concern that aquaculture facilities could contribute to increased transmission of schistosomes. Aquaculture development and the possible problems and their mitigation are discussed. The possible integration of mini-livestock with aquaculture is considered. [ABSTRACT FROM AUTHOR]

Cadmium chloride is a metal salt used in industries in a large scale. Trichogaster (Colisa) fasciata (common name banded gourami) is an air-breathing fresh water fish with both nutritional and ornamental values. In this present study, as per EPA guidelines, acute toxicity bioassay was performed in a 96-h static test method in four replicates, each replicate having one control and five concentrations (25, 50, 75, 100 and 125 mg/L, respectively) of the metal salt. A total of 192 fish was used in the study in four series with each replicate containing 8 fish per concentration. The water temperature was maintained at 20–22℃ during the study. The data observed were analysed statistically on the basis of Finney's Probit Analysis method using SPSS software. The estimated 96-h LC50 value of cadmium chloride for the fish was 49.5 mg/L. [ABSTRACT FROM AUTHOR]

Ca Mau and Kien Giang, the two provinces of the Mekong Delta bordering the Gulf of Thailand, are facing major environmental challenges affecting the agriculture and aquaculture sectors upon which many livelihoods in this region depend on. This study maps the suitability of these two provinces for paddy rice cultivation and shrimp farming according to soil characteristics and current and future environmental conditions for variables found to significantly influence the yield of those two sectors, i.e., the level of saltwater intrusion, water availability for rainfed agriculture, and the length of the growing period. Future environmental conditions were simulated using the MIKE 11 hydrodynamic model forced by four hydrodynamic scenarios, each one representing different extents of saltwater intrusion during both the dry and rainy seasons, while also considering the availability of water resources for rainfed agriculture. The suitability zoning was performed using a GIS-based analytic hierarchy process (AHP) approach, resulting in the categorisation of the land according to four suitability levels for each sector. The analysis reveals that paddy rice cultivation will become more suitable to Kien Giang province while shrimp farming will be more suitable to Ca Mau province if the simulated future environmental conditions materialise. A suitability analysis is essential for optimal utilisation of the land. The approach presented in this study will inform the regional economic development master plan and provide guidance to other delta regions experiencing severe environmental changes and wishing to consider potential future climatic and sea level changes, and their associated impacts, in their land use planning. [ABSTRACT FROM AUTHOR]

Integrated rice–fish culture is a competitive alternative to rice monoculture for environmental sustainability and food productivity. Compared to rice monoculture, rearing fish in rice field ecosystems could increase food (rice and fish) production from this coculture. Moreover, the water productivity of rice–fish coculture is considerably higher than that of rice monoculture, because of double cropping. Despite these benefits, rice–fish coculture has not yet been broadly practiced. One of the potential challenges for the wider adoption of rice–fish coculture is water management. There are two forms of water involved in rice–fish cultivation: (1) blue water–surface and groundwater, and (2) green water–soil water from rainfall. The aim of this article is to focus on key factors determining the adoption of rice–fish cultivation through the effective utilization of blue–green water. We suggest that the efficient application of blue and green water in rice–fish coculture could help confronting water scarcity, reducing water footprint, and increasing water productivity. [ABSTRACT FROM AUTHOR]

The use of chemicals, biologicals and veterinary medicinal products (VMPs) helps in healthy and sustainable fish production. Information on the use of these products is essential for assessing farming practices, potential human health and environmental risks. A questionnaire‐based nationwide survey covering aquaculture farms (n = 2936) producing carps, tilapia, pangasius and rainbow trout in freshwater and shrimp in brackishwater estimated the use of 52 different types of inputs which included disinfectants (597 g t−1), probiotics (2.28 kg t−1), environmental modifiers (22.82 kg t−1), nutritional supplements (1.96 kg t−1), natural anti‐infective agents (293 g t−1), herbicide and piscicides (844 g t−1), antibiotics (2 mg PCU−1), antifungal (4 mg PCU−1), and antiparasitic (14 mg PCU−1) agents. The bulk of these inputs was used for soil and water quality improvement and had low environmental and human safety concerns. The multivariate analysis revealed significant variation in the frequency and quantity of compounds use among farm groups. Redundancy analysis revealed a significant association between the number of products used and stocking density. The survey also showed a considerable influence of education and farming experience on the usage pattern of aquaculture inputs. Results of the study indicated greater reliance of farmers on the use of disinfectants for biosecurity, nutritional supplements for enhanced growth and environmental modifiers for maintaining soil and water quality in culture systems. Though there was no use of restricted antibiotics and antiparasitic agents, the development and implementation of standard regulatory guidelines are essential for safe and effective use of inputs for sustainable aquaculture. [ABSTRACT FROM AUTHOR]

White spot syndrome virus (WSSV), the etiological agent of white spot disease (WSD), is a significant pathogen affecting shrimp farming industry worldwide. White spot syndrome virus is a generalist virus mainly infecting decapod crustaceans. The aims of this review were to: (1) Re‐evaluate and update the status of reported WSSV host and vector species based on the methods used when detecting replication and transmission to shrimp and 2) make a critical evaluation of existing literature on the presence of WSSV in aquatic organisms and the potential role these organisms might play in the transmission of WSSV in pond systems and the wild. An evaluation of literature about WSSV reported host and vector species showed an increase from 33 families to 50 families including 11 families of non‐crustacean hosts, proved the virus continues to spread beyond farmed shrimp and the shrimp pond environment. White spot syndrome virus transmission in the aquatic environment is complex as depicted in our model. Containment of WSSV in ponds and the natural environment is challenging, mainly because of its generalist nature and a lack of understanding about (1) WSSV transmission in the aquatic setting, (2) the route of WSSV transmission among species exist in the aquatic environment and (3) information on the transmission dynamics between WSSV in farmed crustaceans and non‐farmed animals. Information presented in this review provides the research direction on methods to control WSSV. [ABSTRACT FROM AUTHOR]

Copyright of Fishery Modernization is the property of Fishery Modernization Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Neonicotinoids are the most widely used class of insecticides in the world, but they have raised numerous concerns regarding their effects on biodiversity. Thus, the objective of this work was to do a critical review of the contamination of the environment (soil, water, air, biota) by neonicotinoids (acetamiprid, clothianidin, imidacloprid, thiacloprid, thiamethoxam) and of their impacts on terrestrial and aquatic biodiversity. Neonicotinoids are very frequently detected in soils and in freshwater, and they are also found in the air. They have only been recently monitored in coastal and marine environments, but some studies already reported the presence of imidacloprid and thiamethoxam in transitional or semi-enclosed ecosystems (lagoons, bays, and estuaries). The contamination of the environment leads to the exposure and to the contamination of non-target organisms and to negative effects on biodiversity. Direct impacts of neonicotinoids are mainly reported on terrestrial invertebrates (e.g., pollinators, natural enemies, earthworms) and vertebrates (e.g., birds) and on aquatic invertebrates (e.g., arthropods). Impacts on aquatic vertebrate populations and communities, as well as on microorganisms, are less documented. In addition to their toxicity to directly exposed organisms, neonicotinoid induce indirect effects via trophic cascades as demonstrated in several species (terrestrial and aquatic invertebrates). However, more data are needed to reach firmer conclusions and to get a clearer picture of such indirect effects. Finally, we identified specific knowledge gaps that need to be filled to better understand the effects of neonicotinoids on terrestrial, freshwater, and marine organisms, as well as on ecosystem services associated with these biotas., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Atoll societies have adapted their environments and social systems for thousands of years, but the rapid pace of climate change may bring conditions that exceed their adaptive capacities. There is growing interest in the use of 'nature-based solutions' to facilitate the continuation of dignified and meaningful lives on atolls through a changing climate. However, there remains insufficient evidence to conclude that these can make a significant contribution to adaptation on atolls, let alone to develop standards and guidelines for their implementation. A sustained programme of research to clarify the potential of nature-based solutions to support the habitability of atolls is therefore vital. In this paper, we provide a prospectus to guide this research programme: we explain the challenge climate change poses to atoll societies, discuss past and potential future applications of nature-based solutions and outline an agenda for transdisciplinary research to advance knowledge of the efficacy and feasibility of nature-based solutions to sustain the habitability of atolls. This article is part of the theme issue 'Nurturing resilient marine ecosystems'. [ABSTRACT FROM AUTHOR]

The pesticides used have contributed to increasing food production; it has also caused them to be found in most ecosystems and have negative effects on biota. The neotropical otter (Lontra longicaudis) is vulnerable to pesticide accumulation and is characterized by being elusive, so it is necessary to address the use of indirect techniques that evaluate its populations' state in an efficient, logistically simple, and non-invasive way. This study aimed to determine the concentration of 20 pesticides in neotropical otter feces in the Ayuquila-Armería basin and to describe the spatiotemporal variation of these pesticides. The presence of 11 pesticides was determined. Imazalil, picloram, and malathion the pesticides with the highest concentrations; emamectin, λ-cyhalothrin, methomyl, and picloram were present in all samples. Emamectin was the only pesticide that presented significant differences concerning the temporality of the samplings, presenting higher concentrations in the wet season. Molinate concentrations showed significant differences concerning the location of the sampling sections in the basin; the lower part of the basin presented higher concentrations. The distribution of the populations of L. longicaudis in the Ayuquila-Armería basin does not respond to the degree of contamination by pesticides in surface waters or to the proximity to agricultural activities, and this in places with evident chemical and organic contamination and human presence. The use of otter feces for pesticide monitoring is an accepted non-invasive method to assess the degree of exposure and can be used to determine sites with pollution problems. [ABSTRACT FROM AUTHOR]

The combined effects of anthropogenic and climate change factors have severely impacted the yield from the traditional food production system resulting in food insecurity and other socio-economic problems. The predominant food production systems have been reviewed as unsustainable and environmentally unfriendly; therefore, there is a need to adopt innovative and sustainable food production systems locally and globally. This article addresses traditional food production challenges by exploring low-cost aquaponics to attain food security and socio-economic development, notably in poor communities. A low-cost aquaponic system was first developed conceptually using the reflective practice approach. Its applicability to sustainable livelihoods and economic development is explored. Subsequently, the critical success factors of low-cost aquaponics were identified. These include infrastructure design, microclimatic environment, human ecology, and sociocultural dynamics. Due to its integrative and multiple application scenarios ranging from low-tech to high-tech, aquaponics is a complex and unconventional food production system. The reverse scalability to a small scale, the low-cost set-up makes it sustainable in achieving food security and socio-economic development in poor communities. [ABSTRACT FROM AUTHOR]

As the world's leading producer of farmed aquatic food products, China faces great uncertainty concerning the further sustainable development of its aquaculture industry due to high and increasing pressure from environmental and resource constraints. To realize truly sustainable development, it is imperative to establish an evaluation system that integrates social, economic, environmental and resource criteria, and optimizes aquaculture systems through a holistic approach. Here, we used analytical hierarchy processes combined with expert judgment and objective data to assess the sustainability of 10 major aquaculture production systems (APSs) in China. Based on the evaluation results, we propose the ecological intensification of aquaculture systems (ELIAS), rationally integrating anthropogenic inputs with aquaculture ecosystem services, to improve the sustainability of APSs. The holistic evaluation system and ELIAS are fundamental and critical for the future development of aquaculture in China and globally. [ABSTRACT FROM AUTHOR]

The contribution of aquatic animal protein to the global, animal-source protein supply and the relative importance of aquaculture to capture fisheries in supplying this protein is relevant in assessments and decisions related to the future of aquatic food production and its security. Meat of terrestrial animals, milk, and eggs resulted in 76,966 Kt crude protein compared with 13,950 Kt or 15.3% from aquatic animals in 2018.While aquaculture produced a greater tonnage of aquatic animals, capture fisheries resulted in 7,135 Kt crude protein while aquaculture yielded 6,815 Kt. Capture fisheries production has not increased in the past two decades, and aquaculture production must increase to assure the growing demand for fisheries products by a larger and more affluent population. We estimated based on status quo consumption, that aquaculture production would need to increase from 82,087 Kt in 2018 to 129,000 Kt by 2050 to meet the demand of the greater population. About two-thirds of finfish and crustacean production by aquaculture is feed-based, and feeds for these species include fishmeal and fish oil as ingredients. Aquaculture feeds require a major portion of the global supply of fishmeal and fish oil. An estimated 71.0% of fishmeal and 73.9% of fish oil are made from the catch with the rest coming from aquatic animal processing waste. The catch of small, pelagic fish from the ocean is not predicted to increase in the future. Aquaculture should reduce its fishmeal and oil use to lessen its dependency on small wild fish important to the integrity of marine food webs and food security for the poor in many coastal areas. Fishmeal and fish oil shortages for use in aquaculture feed will result in a limit on production in the future if goals to lessen their use in feeds are not met. [ABSTRACT FROM AUTHOR]

Two alternative physical adaptations of freshwater-aquaculture farmers were observed along the upstream Bangpakong Watershed, Thailand. First was the modification of aquaculture types: (1) completely changing former species to others; (2) mixing freshwater prawn with current cultured species; (3) mixing fish with L. vannamei, and second was the direct reaction to environmental changes, including adding freshwater into cultured ponds to reduce temperature and dilute salt concentration; modifying pond-depth; aeration application; and reducing the amount of food or net covering on the water surface during flooding. Principal component analysis revealed that four key components (Options, Learning, Competitiveness, and Plan) reflected the perceived adaptive capacity of farmers to environmental changes. However, culture types have no significant effect on these four components. Farmers with an alternative source of income and practicing monoculture fish farming tend to have a greater ability to change occupation. Old age and more extended experience in aquaculture indicated a low ability to change occupation. The well-educated farmers and farmers who preferred to pass on aquaculture occupation to their children showed higher ability to learn and adapt, but this is not the case for older farmers. Thus, understanding the adaptations of the farmers may assist in promoting appropriate development programs based on their contexts as well as helping decisionmakers to have a better plan for strengthening their adaptive capacities based on their perceptions. [ABSTRACT FROM AUTHOR]

As water pollution poses an increasing risk worldwide, it is timely to assess the achievements of the aquatic macroinvertebrate ecotoxicology to provide a sound basis for the discipline’s future and support the development of biomonitoring. Aquatic and semi-aquatic bugs (Hemiptera: Nepomorpha, Gerromorpha) are ubiquitous in almost all water types, sometimes in high densities, and play a significant role in organic material turnover and energy flow. Nevertheless, they are ignored in the water pollution biomonitoring schemes. Here, based on 300 papers, we review and evaluate the effects of chemical pesticides, microorganism-derived pesticides, insecticides of plant origin, heavy metals, eutrophication, salinisation and light pollution which are summarised for the first time. Our review encompasses the results of 100 laboratory and 39 semi-field/field experiments with 47 pesticides and 70 active ingredients. Pyrethroids were found to be more toxic than organochlorine, organophosphate and neonicotinoid insecticides to water bugs, like other macroinvertebrate groups. Additionally, in 10 out of 17 cases, the recommended field concentration of the pesticide was higher than the LC50 values, indicating potential hazards to water bugs. The recommended field concentrations of pesticides used in mosquito larvae control were found non-toxic to water bugs. As very few replicated studies are available, other findings on the effects of pesticides cannot be generalised. The microorganism-derived pesticide Bti appears to be safe when used at the recommended field concentration. Data indicates that plant-derived pesticides are safe with a high degree of certainty. We have identified three research areas where water bugs could be better involved in water biomonitoring. First, some Halobates spp. are excellent, and Gerris spp. are promising sentinels for Cd contamination. Second, Micronecta and, to a certain extent, Corixidae species composition is connected to and the indicator of eutrophication. Third, the species composition of the Corixidae is related to salinisation, and a preliminary method to quantify the relationship is already available. Our review highlights the potential of water bugs in water pollution monitoring. [ABSTRACT FROM AUTHOR]

Shrimp aquaculture is the biggest source of export income in Vietnam. However, the development of the shrimp poses a serious threat to coastal mangroves by converting coastal mangroves into shrimp farms. Much effort has been made to replant mangroves and reduce the impacts of shrimp farming on the environment, and maintaining mangrove coverage at 30–50% of total farm area has provided the highest benefits in the integrated mangrove shrimp model. In this study, we re-examine the benefits of forest cover on the survival and yield of tiger shrimp (Penaeus monodon) in the integrated mangrove shrimp farming systems in Ca Mau province, Vietnam. The study found positive linear correlations of log transformed survival and yield of tiger shrimp with forest cover of the forms: Ln (survival) = − 1.39 + 0.038 × forest coverage (r2 = 0.22; p value = 0.0007); Ln (yield) = 3.55 + 0.026 × forest coverage (r2 = 0.16; p value = 0.004). The households with high forest cover (i.e., > 45%) also had 1.07 ± 0.29 and 1.39 ± 0.36 (CI 95%, p value = 0.000) kg ha−1 higher yield per night harvest than those with medium and low forest cover, respectively. As a result, households with high forest cover have higher benefits than those with lower forest cover. Our findings together with previous published studies lead to the recommendation that farmers maintain mangroves in farming systems for better economic and environmental benefits. [ABSTRACT FROM AUTHOR]

This take a look at become directed to discover the effect of temperature on increase and survival rate of African catfish. Different temperatures as 24, 27, 30, 32, 34oC and 36oC had been examined and 27oC become a control. Plasma cortisol, plasma glucose, osmotic strain, and increase overall performance parameters had been envisioned at some point of the experimental duration of 25 days. The outcomes discovered that increase and survival rate had been prompted with the aid of using excessive temperature stage. Moreover, cortisol, glucose, and osmotic strain had been without delay proportional to the temperature stage. Therefore, it become concluded that multiplied temperature stage impacts increase and survival and different hormones of African catfish. So that a few growth in water temperature might appear like useful to catfish subculture overall performance. [ABSTRACT FROM AUTHOR]

FLOCponics is an alternative type of aquaponics that integrates biofloc technology (BFT) with soilless plant production. The aims of this paper are to present a detailed overview of the FLOCponics system's designs and performance, discuss their sustainability, highlight the current challenges, and give directions for future research. Data sources include papers containing the keywords bioflocs and hydroponics, aquaponics and/or plant production. In view of the small number of publications and the lack of standardization in experimental design and system setup, it was concluded that FLOCponics is still in its initial research stage. With respect to the animal and plant yields in FLOCponics, inconsistent results were found. Some investigations presented better or similar yield results in this system compared to traditional cultures, while others found the opposite. One of the key challenges of using FLOCponics is the effective control of solids. Refining the system's design was the main recommended improvement. Moreover, this paper highlights that the commercial application of FLOCponics will require extensive research that clarifies its technical and economic aspects, originating from experimental or pilot‐scale setups with characteristics similar to commercial production. This review provides and discusses information that can be useful for the effective development of FLOCponics, guiding further research to make FLOCponics commercially feasible and thus contributing to sustainable aquaculture production. [ABSTRACT FROM AUTHOR]

Knowledge of the shared resources—or commons—that aquaculture systems rely on, and the appropriate rule and norm systems to govern them—or institutions—is far behind other natural resource use sectors. In this article, we provide a conceptual framework for identifying the social and environmental commons creating collective action problems for aquaculture governance. Collective action problems, or social dilemmas, create problems for governing shared resources because the typical strategies for individual use (maximisation; free riding) are often divergent from broader group interests (e.g. fair contributions; sustainable use). This framework helps identify two types of collective action problems in aquaculture: first‐order (direct use and provision of commons) and second‐order (provision, maintenance and adaptation of institutions to govern commons). First‐order aquaculture commons with governance challenges include water quality, water quantity, physical space, inputs, genetic diversity, mitigating infectious disease, earth and climate stability, infrastructure, knowledge and money. Second‐order institutions govern the use of first‐order commons. These include rule and norm systems that structure property rights and markets, aiming to better align individual behaviour and collective interests (e.g. sustainability goals) through governance. However, which combination of institutions will fit best is likely to be unique to context, where aquaculture has important differences from capture fisheries and agriculture. We provide four case examples applying our conceptual framework to identify existing aquaculture commons, institutions and governance challenges in Peru (mariculture), the Philippines (earthen ponds), Nepal (raceways) and Denmark (recirculation). [ABSTRACT FROM AUTHOR]

Background: A longitudinal study was conducted to analyze farm characteristics, farm practices, and biosecurity measures that influenced the occurrence of white spot disease (WSD) in shrimp farming in Rayong, Thailand. Methods: Data were collected using a structured interview schedule administered between October 2017 and September 2019. A generalized estimating equations (GEE) model was used to identify risk factors. From the 270 responses, 86 possible risk factors were analyzed using univariate and multivariate analysis. Results: We found that 17 possible risk factors were statistically significant with an alpha level of 1% and associated with WSD status. In the final model, multivariate analysis found that two independent variables were statistically significant. First, the absence of inclement weather during ponding was a statistically significant factor associated with WSD occurrence and it prevented WSD occurrence as the odds ratio (OR) was <1 (OR = 0.196, P = 1.3 × 10-5). Second, the separation of ponds into three specific types (cultured, water treatment, and pond for water reservoir) was significantly associated with WSD occurrence. Likewise, the presence of this ponding system was a protective factor against WSD (OR = 0.0828, P = 0.001). Conclusions: The results of this study offer a reference for farmers and relevant authorities when addressing WSD occurrence in shrimp farming. In addition, our results can help relevant authorities in controlling WSD in other endemic areas. [ABSTRACT FROM AUTHOR]

Aquaculture is remarkably one of the most promising industries among the food-producing industries in the world. Aquaculture production as well as fish consumption per capita have been dramatically increasing over the past two decades. Shifting of culture method from semi-intensive to intensive technique and applying of antibiotics to control the disease outbreak are the major factors for the increasing trend of aquaculture production. Antibiotics are usually present at subtherapeutic levels in the aquaculture environment, which increases the selective pressure to the resistant bacteria and stimulates resistant gene transfer in the aquatic environment. It is now widely documented that antibiotic resistance genes and resistant bacteria are transported from the aquatic environment to the terrestrial environment and may pose adverse effects on human and animal health. However, data related to antibiotic usage and bacterial resistance in aquaculture is very limited or even absent in major aquaculture-producing countries. In particular, residual levels of antibiotics in fish and shellfish are not well documented. Recently, some of the countries have already decided the maximum residue levels (MRLs) of antibiotics in fish muscle or skin; however, many antibiotics are yet not to be decided. Therefore, an urgent universal effort needs to be taken to monitor antibiotic concentration and resistant bacteria particularly multiple antibiotic-resistant bacteria and to assess the associated risks in aquaculture. Finally, we suggest to take an initiative to make a uniform antibiotic registration process, to establish the MRLs for fish/shrimp and to ensure the use of only aquaculture antibiotics in fish and shellfish farming globally. [ABSTRACT FROM AUTHOR]

Immobilized microalgae are a promising approach to incorporate microalgae in recirculating aquaculture system (RAS) for water purification. In the present study, two types of biosorbents including sodium alginate–immobilized Scenedesmus spp. and Chlorella spp. beads (algal beads) and sodium alginate beads without microalgae (alginate beads) were prepared. In the first experiment (static test), the potential of two biosorbents to remove different concentrations of total ammonia nitrogen (TAN) and total phosphorus (TP) from water was investigated. In the second experiment, two prepared biosorbents were used as biofilter in a RAS for rearing African cichlid (Labidochromis lividus) for 30 days. The survival rate and growth indices of fingerling fish and removal efficiency of two biosorbents for TAN, NO3—N, and TP were determined. The results of static test showed that the removal efficiency and uptake capacity of the two biosorbents for TAN and TP increased during 30 days of the experiment, and these values for the algal beads were higher than the alginate beads. The TAN removal efficiency of the two biosorbents increased with increasing TAN concentration from 0.5 to 5 mg L−1. The application of algal beads in the RAS improved the survival rate, final weight, final length, weight gain, and daily growth index (DGI%) indices of fish compared to those cultured in the RAS containing the alginate beads and the control (P<0.05). The algal and alginate beads decreased the TAN concentration by 42.85% and 28.57% compared to the control after 30 days of cultivation period, respectively. The uptake of nitrate was not observed by the two biosorbents during cultivation period. The TP removal efficiency of algal beads reached 44.90% after 30 days. The findings of this study indicated that the sodium alginate–immobilized microalgae could be considered as a suitable biofilter to be incorporated into a RAS to improve water quality and consequently enhance the growth and health of fish. [ABSTRACT FROM AUTHOR]

Bauhinia thonningii is a woody leguminous tree species, which is endowed with enormous soil improvement, medicinal, nutritional, and socio-ecological benefits in African. The current study was carried out to systematically review and document findings on the multiple benefits of B. thonningii and thereby identify gaps and opportunities for further comprehensive studies. A systematic and manual search was conducted to retrieve relevant articles published from 1974 to June 2021. Electronic databases of PubMed (Medline), Google Scholar, and grey literature were employed to access the studies. Accordingly, 100 articles and 2 thesis papers were finally included in this study. The study shows B. thonningii tree species improve soil fertility and its abundant litter accumulated from the leaves of B. thonningii trees contributed to increased organic carbon and total nitrogen content. The plant parts are used in several traditional medicine to treat different human and animal ailments. The pods and seeds of the plant contained a lot of important nutrients and nutritional value, beneficial to human as well as animal health. The plant plays a key role in biomass production and carbon sequestration potential. Owing to its multiple benefits, there is an urgent need to facilitate the scaling-up of the use of the tree by using various approaches. The findings will serve as a useful reference for further in depth investigations on the multifunctional uses of the plant across different ecozone as well as supporting the scale up of the benefits of the species. [ABSTRACT FROM AUTHOR]

As a study of cryoprotectant toxicity is an essential prerequisite for the development of a cryopreservation protocol, this study focuses on determining the toxicity of four permeable cryoprotectants: dimethyl sulfoxide (DMSO), propylene glycol (PG), methanol (MeOH), and acetamide (Ac). In cryoprotectant toxicity experiments, striped gourami (Trichogaster fasciata) embryos at three different developmental stages (multi cell, 100% epiboly, and proliferation of somites) were exposed to cryoprotectant solutions with concentrations from 1 to 4 M for a period of 5 and 15 min. Following these treatments, the embryos were incubated until the evaluation of hatching rate. Embryos were tolerant to low concentrations of all cryoprotectants tested in the range of 1 to 2 M for all developmental stages. Early stage embryos were more vulnerable to high concentration (3 and 4 M) than late stage embryos. Results also showed that as concentration and duration of exposure increased, the hatching rate significantly decrease (P < 0.05). On a molar-equivalent basis, DMSO appeared to be less toxic to PG, MeOH, and Ac in general. Exposure to cryoprotectants revealed a stage-dependent sensitivity. Toxicity increased in the order of MeOH < DMSO < PG < Ac in multi cell stage and DMSO < MeOH < PG < Ac in 100% epiboly and proliferation of somites stages. The proliferation of somites stage embryos was less sensitive to exposure to cryoprotectants than multi cell and 100% epiboly stages. These findings could be important for designing cryopreservation protocols for this demanding ornamental species. [ABSTRACT FROM AUTHOR]

Recirculating aquaculture system (RAS) is a unique approach that offers total control to culture a wide variety of aquatic species. As capital investment is higher for setting up RAS, it is necessary to conduct an economic feasibility analysis based on real data. A structured questionnaire was used to collect all economic and technical data on two catfish species, viz., Pabda (Ompok pabda) and Shing (Heteropneustes fossilis), cultured in an RAS farm. The ultimate objective was to estimate net cash flow, net present value (NPV), profitability index (PI), payback period, discounted payback period, internal rate of return (IRR), and sensitivity analysis to find out the best profitability indicators. The analysis revealed that the IRR were 4% and 16% for Pabda and Shing production, respectively. However, for Pabda and Shing productions, the payback periods were 15 years and 4 months and 6 years and 2 months, respectively. The NPV value was positive for Shing production and negative for Pabda. On the other hand, the PI was lower than one for Pabda production and higher than one for Shing production. Therefore, the results showed that the Shing production in the RAS facility could be economically feasible; however, Pabda production may not be viable in RAS due to lower production and longer culture period. This study may suggest that by increasing the production capacity of the farm and market price of the product through the proper supply chain and by decreasing the initial investment, cost of fingerlings and feed, profitability can be achieved in RAS in Bangladesh. [ABSTRACT FROM AUTHOR]

In the discourse about the development of farmed animal production (terrestrial livestock production and aquaculture) in the tropics, two important food system outcomes emerge: (1) to supply animal-sourced food (ASF) at a level that suffices healthy future diets, including for poor people, and (2) to contribute to climate change mitigation and minimize pollution with nitrogen and phosphorus. Livestock production and aquaculture contribute to food security directly by increasing producers' food diversity and availability, but also that of urban consumers, and indirectly through income generation and increased farm resilience. Recently, circularity has come to the fore as an integrated approach to food system development. Circularity has four cornerstones: (1) food crops have highest priority (which implies no food-feed competition), (2) avoid losses, (3) recycle waste and (4) use animals to unlock biomass that humans cannot eat. In this review, the role of farmed animals in circular food systems in the tropics is presented in four case studies and the impacts of circularity on food security and environmental impact mitigation are discussed. The cases are ruminants in grazing systems in West Africa and in Colombia, fish in pond aquaculture in general, and land-limited dairy production in Indonesia. Additionally, options for novel protein sources for use in livestock and fish feeding are presented. It is concluded that farmed animals are important in circular food systems because of their use of land unsuited for crop production, their upgrading of crop residues, and their supply of manure to crop production. Nevertheless, the increasing demand for ASF puts pressure on important characteristics of circularity, such as minimizing food-feed competition, maximization of use of waste streams in feed, and the value of manure for fertilization. Hence, in line with conclusions for Western countries, maximum circularity and sustainability of food systems can only be achieved by optimizing the population size of animals. Thus, a sustainable contribution of ASF production to global food security is complex and in not only a technical matter or outcome of an economic process balancing supply and demand. It requires governance for which public, private, and social actors need to partner. [ABSTRACT FROM AUTHOR]

Amphibians are declining around the world as they are particularly sensitive to multiple environmental stressors, among them the increase of UVB radiation and the environmental contaminations of body waters caused by agrochemicals. Because of the limited research on the interaction between agrochemicals and UVB radiation on tropical amphibians, we performed this study to test the hypothesis that the exposure to UVB radiation will enhance the toxic effects of the organophosphorus (OPs) insecticides chlorpyrifos, diazinon and monocrotophos, which are widely used in Colombia, on tadpoles from three tropical anuran species. Under laboratory conditions, we exposed independently tadpoles of Boana xerophylla, Engystomops pustulosus and Rhinella horribilis to each of the three insecticides with the presence of UVB radiation and without UVB, during 96 h toxicity tests. We then examined their effects on tadpole mortality, capacity to swim and total length. We found that UVB enhanced the mortality of insecticides (these treatments had a lower LC50 than those without UVB radiation), increased the tadpole immobility (they were unable to swim), and decreased the total length. Therefore, we validated the prediction that UVB radiation enhances the toxicity of the OPs insecticides studied on our anuran species and consequently may be one of the causal factors of amphibian population declines in the tropical countries. However, we suggest to perform more realistic field studies in areas with agrochemical presence to a better understanding of the effect of these stressors on anurans as there are environmental factors that attenuate underwater UVB radiation and toxicity in aquatic organisms, although it is also known that under field conditions some OPs insecticides become more toxic in the presence of UVB. [ABSTRACT FROM AUTHOR]

The demographic pressure in Benin has led to an increase in demand for cereals, in particular maize (Zea mays L.), which constitutes the staple diet for the populations. Yet, in this context of climatic variability, the environmental conditions greatly limit the yields of this crop. The purpose of this study was to compare the agro-morphological characteristics of nine (09) local and improved varieties of maize (Zea mays L.) by screening the most efficient and promising varieties which better meet the agro-ecological conditions of the district of Djidja (southern Benin). To more control sol homogeneity, semi-Latin square design with three repetitions was used as experimental design during the trial. Twelve agro-morphological characters selected from the maize descriptors were used to compare the varieties. The results showed that the agro-morphological characteristics varied significantly depending on the varieties studied except for the emergence rate. The improved variety IWD SYN W was the best tolerant variety to climate change for cultivation in the municipality of Djidja comparatively to the other eight varieties. These results can directly support the maize productivity programs in southern Benin. [ABSTRACT FROM AUTHOR]

Pacific white shrimp (Penaeus vannamei) farming is an important commercial aquaculture production system contributing substantially to the economic and societal development in India. Though technically efficient, shrimp farming is potentially susceptible to production risks. A risk assessment study was undertaken to ascertain the potential risks in P. vannamei shrimp farming by developing a framework consisting of risk perception and assessment, communication of risk management practices, and evaluation of their efficiency in tackling the risks. The primary data collected from a proportionate randomly chosen 604 shrimp farmers across the coastal states revealed that P. vannamei shrimp farming was prone to twenty-seven risks having very low to very high probability of occurrence with marginally negative to a catastrophic impact on production and income. Appropriate risk-preventive and management measures were proposed and suitably communicated to the shrimp farmers through training workshops, farmer handbooks in vernacular languages, and launching a mobile app module on on-farm risk assessment. A follow-up study conducted among a random subset of the original sample indicated that 76% of the farmers adopted the proposed risk management practices and experienced that the practices were highly efficient (up to 80%) in tackling the risks associated with shrimp farming. Furthermore, it was observed that adoption of risk management practices is essential to have a successful shrimp production of marketable size and an additional expenditure for adoption of these practices was estimated to be 0.5 USD per kg of shrimp produced. Shrimp farming is a delicate and dynamic production system, and it is unrealistic to avoid the emergence of hazards in the production cycle. Therefore, it is imperative to train the farmers on better management practices (BMP) and develop a certification plan to accredit the farms for the adoption of BMPs that would ensure an economically viable shrimp production in India. [ABSTRACT FROM AUTHOR]

Pesticides can enter aquatic environments via direct application, via overspray or drift during application, or by runoff or leaching from fields during rain events, where they can have unintended effects on non-target aquatic biota. As such, Fisheries and Oceans Canada identified a need to prioritize current-use pesticides based on potential risks towards fish, their prey species, and habitats in Canada. A literature review was conducted to: (1) Identify current-use pesticides of concern for Canadian marine and freshwater environments based on use and environmental presence in Canada, (2) Outline current knowledge on the biological effects of the pesticides of concern, and (3) Identify general data gaps specific to biological effects of pesticides on aquatic species. Prioritization was based upon recent sales data, measured concentrations in Canadian aquatic environments between 2000 and 2020, and inherent toxicity as represented by aquatic guideline values. Prioritization identified 55 pesticides for further research nationally. Based on rank, a sub-group of seven were chosen as the top-priority pesticides, including three herbicides (atrazine, diquat, and S-metolachlor), three insecticides (chlorpyrifos, clothianidin, and permethrin), and one fungicide (chlorothalonil). A number of knowledge gaps became apparent through this process, including gaps in our understanding of sub-lethal toxicity, environmental fate, species sensitivity distributions, and/or surface water concentrations for each of the active ingredients reviewed. More generally, we identified a need for more baseline fish and fish habitat data, ongoing environmental monitoring, development of marine and sediment-toxicity benchmarks, improved study design including sufficiently low method detection limits, and collaboration around accessible data reporting and management. [ABSTRACT FROM AUTHOR]

Nowadays, tropical forest landscapes are commonly characterized by a multitude of interacting institutions and actors with competing land-use interests. In these settings, indigenous and tribal communities are often marginalized in landscape-level decision making. Inclusive landscape governance inherently integrates diverse knowledge systems, including those of indigenous and tribal communities. Increasingly, geo-information tools are recognized as appropriate tools to integrate diverse interests and legitimize the voices, values, and knowledge of indigenous and tribal communities in landscape governance. In this paper, we present the contribution of the integrated application of three participatory geo-information tools to inclusive landscape governance in the Upper Suriname River Basin in Suriname: (i) Participatory 3-Dimensional Modelling, (ii) the Trade-off! game, and (iii) participatory scenario planning. The participatory 3-dimensional modelling enabled easy participation of community members, documentation of traditional, tacit knowledge and social learning. The Trade-off! game stimulated capacity building and understanding of land-use trade-offs. The participatory scenario planning exercise helped landscape actors to reflect on their own and others' desired futures while building consensus. Our results emphasize the importance of systematically considering tool attributes and key factors, such as facilitation, for participatory geo-information tools to be optimally used and fit with local contexts. The results also show how combining the tools helped to build momentum and led to diverse yet complementary insights, thereby demonstrating the benefits of integrating multiple tools to address inclusive landscape governance issues. [ABSTRACT FROM AUTHOR]

Despite an expansion of production, pangasius farmers have experienced economic challenges in Vietnam. The aim of this study was to identify optimum economic alternatives for pangasius farmers. A single-stage stochastic frontier analysis was used to estimate the economic efficiency of pangasius farms and investigate the farm size–economic efficiency relationship using cross-sectional data collected on Vietnamese pangasius farms. The study found a nonlinear relationship between farm size and economic efficiency, with economic efficiency increasing until the farm area reached a threshold of 26.9 ha, then falling due to transaction and agency costs under asymmetric information. The farming experience of the decision-makers negatively affected efficiency. Similar to previous studies, we found feed and fingerling costs were essential input factors for farms. Based on these results, we recommend three strategies for improving the economic efficiency of farms are: providing timely market information to farmers; determining the optimal farming scale depending upon the specific farmer's available resources; and using a good quality of fingerlings and feed. [ABSTRACT FROM AUTHOR]