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Inventory and Distribution of Benthic Macroinvertebrates, Indicators of Water Quality in Four Forested Watercourses in Centre Region of Cameroon
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作者 Eric B. Biram à Ngon Sylvie B. Chinche +9 位作者 Josephine Ndjama Jean Dzavi Donald L. Nyame Mbia Mathias Nwaha Serge R. Gwos Nhiomock Blaise R. Mboye Ivone L. Tchaouapi Ulrich Tchouta Chamberline Ngalamou Samuel Foto Menbohan 《Open Journal of Ecology》 2024年第4期381-394,共14页
The inventory of benthic macroinvertebrate species was carried out in some streams of the Mefou catchment area, from August 2021 to August 2022, in order to determine the biological groups that make up the population ... The inventory of benthic macroinvertebrate species was carried out in some streams of the Mefou catchment area, from August 2021 to August 2022, in order to determine the biological groups that make up the population and characterise these environments. The dataset acquired during this study made it possible to update the existing database and contribute to the knowledge of the biological groups associated in these environments, and to provide additional information on the existing ones in relation to bioindication. Overall 80 families were identified and, on the basis of frequencies of occurrence greater than 75%, 22 families were retained as potential biological indicators. The remarkable diversity of insects and the low abundance of Diptera reflect the low degradation of environments and the good quality of water. The high diversity indices obtained reflect the maintenance of the favourable ecological conditions that favours the development of a balanced and, integrated biological community capable of adapting to changes. 展开更多
关键词 Benthic Macroinvertebrates BIOINDICATORS Biological Quality Forest Watercourse Cameroon
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Effect of the Dietary Substitution of Fish Meal with Achatina fulica Meat Meal on the Growth Performance and Production Cost of African Catfish (Clarias gariepinus) Fingerlings
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作者 Divine Ewane Akeson Akeh Andoh +4 位作者 Fidelis Narika Ambeno Bertha Anyizi Nkemnyi Mbeng Ashu Arrey Benedicta Oshuware Oben Pius Mbu Oben 《Open Journal of Animal Sciences》 2024年第2期123-136,共14页
Fishmeal is the most preferred source of protein in aquafeeds, but it is expensive and scarce. Hence, Achatina fulica meat meal (AFM), which is much less preferred for human consumption out of three species of African... Fishmeal is the most preferred source of protein in aquafeeds, but it is expensive and scarce. Hence, Achatina fulica meat meal (AFM), which is much less preferred for human consumption out of three species of African giant land snails, was tested as a fishmeal substitute for Clarias gariepinus growth. Five iso-nitrogenous and iso-calorific diets were formulated, in which AFM substituted fish meal at 0% (control or Diet A), 25% (Diet B), 50% (Diet C), 75% (Diet D) and 100% (Diet E). These dietary treatments were each replicated thrice in a completely randomized design experiment, using 36-L plastic tanks in which the fish were fed daily rations corresponding to 5% of their body weight, for 8 weeks. Water quality parameters in the tanks were monitored. Proximate analyses were conducted on the fish meal, snail meal and experimental diets before the feeding trials. Cost-benefit analysis of the different diets was performed. The crude protein content of AFM (69.18%) was significantly higher than that of fish meal (55.81%). There was no significant difference (P > 0.05) in the mean weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio and survival rate in fish fed Diet A and Diet B. The best protein efficiency ratio (0.77) was recorded in fish fed Diet B. Furthermore, the survival rate of fish increased with increased levels of AFM substitution. Water quality parameters were within a suitable range for tropical fish culture, indicating that the AFM did not pollute the water. The fish fed 25% AFM diet significantly (P Clarias gariepinus diets at a 25% substitution level. The aquaculture industry can thus exploit the availability of this feed resource. 展开更多
关键词 Fish Meal Achatina fulica Meat Meal AQUAFEEDS Clarias gariepinus
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Chemical Determination of Base Status Metals in Soil Sediments and Particulate Matter in Wellington Industrial Estate Location
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作者 Richard Tamba Simbo Jerry Yeke Paye Fayia Francis Nyuma 《Open Journal of Applied Sciences》 2024年第5期1338-1352,共15页
This research study explored the levels of base status metals in soil sediments and particulate matter in the wellington industrial estate location;the main objectives were to: 1) determine sodium and potassium, 2) de... This research study explored the levels of base status metals in soil sediments and particulate matter in the wellington industrial estate location;the main objectives were to: 1) determine sodium and potassium, 2) determine calcium and magnesium, 3) determine available iron. The following hypotheses were put forward;H<sub>0</sub><sub>a</sub>: there is no significant difference in the concentration levels between Ca and Mg in the study area, H<sub>1</sub><sub>a</sub>: there is significant difference in the concentration levels between Ca and Mg in the study area, H<sub>0</sub><sub>b</sub>: there is no significant difference in the concentration levels between Na and K in the study area, H<sub>1</sub><sub>b</sub>: there is significant difference in the concentration levels between Na and K in the study area. Six locations were used to collect samples with the aid of scoop and gravel free auger (at varying depths of 0 - 5 cm and 5 - 10 cm) which are Wellington Industrial Estate Area 1 (WIEL 1), (WIEL 2), (WIEL 3), (WIEL 4), (WIEL 5), (WIEL 6);the samples were given laboratory treatment. Flame photometer, EDTA, and Spectrophotometer were used in the determinations of sodium and potassium, calcium and magnesium, and available iron respectively. The results indicated that levels of potassium were in medium range (moderately high);sodium levels were generally low when compared to Brook’s classification table. Levels of calcium were generally low and those of magnesium were moderate based on Brook’s table of classification. Levels of available iron which fall within the range of Quijano-Guerta (2003) were high;this implies such levels can lead to toxicity. In all locations, there was decrease in the levels of each metal in the samples with (5 - 10 cm) depth. 展开更多
关键词 Deposition Environment PARTICULATE Sediment TOXICITY
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Structure and Dynamics of Fisheries in Nigeria
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作者 Nwafili Sylvanus A. GAO TianXiang 《Journal of Ocean University of China》 SCIE CAS 2007年第3期281-291,共11页
The changes that have taken place in Nigerian fisheries are reviewed. Artisanal fishery has continued to dominate the fisheries,contributing over 85% of total fish production. The inland water and coastal seas are ful... The changes that have taken place in Nigerian fisheries are reviewed. Artisanal fishery has continued to dominate the fisheries,contributing over 85% of total fish production. The inland water and coastal seas are fully exploited and the increase in fishery production is not likely. Aquaculture potentials remain untapped as much as deep-sea fisheries. The combined potential of the fisheries resources-freshwater,marine and aquaculture can meet over 90% of the nation's demand for fish. Opportunities for invest-ments,therefore,exist in the various subsectors,especially in the areas of storage,processing and preservation for the capture fishery and fish seed multiplication for aquaculture. 展开更多
关键词 渔业 水产业 尼日利亚 海洋资源
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Marine Fishermen’s Perception about Consequences of Climate Change on Fisheries in Tamil Nadu State,India
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作者 Kapparapu Sai Susmitha Bhargavi Nambali Valsalan Sujathkumar +1 位作者 Rajagopal Santhakumar Paulraj Jawahar 《Journal of Agricultural Science and Technology(B)》 2020年第3期186-193,共8页
Global climate change has become a critical barrier in the twenty-first century and it alarms the marine fishermen to respond and react until conditions become more adverse.Interaction with climate by humans occurs at... Global climate change has become a critical barrier in the twenty-first century and it alarms the marine fishermen to respond and react until conditions become more adverse.Interaction with climate by humans occurs at all levels,but recent research has focused on industries,technological and demographic aspects.So far,less attention has been paid to investigate the factors which affect perception and decision-making at the individual level.The uncertain condition of climate on marine fisheries from the last two decades had created drastic change in ecosystems as well as in the fishers’livelihood.Fishers are the group who first experiences the bitter conditions of climate change on marine fisheries because their livelihood depends highly on the marine resources.Therefore,the fishers’perception about the consequences of climate change on fisheries may help to emerge the fisheries by implicating certain productive management measures.The research has been carried out in the two southern coastal districts of Ramanathapuram and Kanyakumari,Tamil Nadu state to find out the fishers’perception of the consequences of climate change on fisheries.A sample size consisting of 120 marine fishermen were randomly selected and interviewed.The results inferred that increase in cost of fishing,increase in fishing investments,decline in fishing days,reduction in fish diversity and fish catches were the major consequences faced by fishers due to the climate change. 展开更多
关键词 Marine fishermen PERCEPTION climate change consequences constraints.
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Local-Scale Governance: A Review of the Zambian Approach to Fisheries Management
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作者 Lloyd Haambiya Emmanuel Kaunda +2 位作者 Jeremy Likongwe Daimon Kambewa Kagoli Muyangali 《Journal of Agricultural Science and Technology(B)》 2015年第2期81-92,共12页
关键词 渔业管理 赞比亚 利益相关者 共同管理 综述 治理 过度捕捞 渔业资源
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Broader applicability of the metacoupling framework than Tobler’s first law of geography for global sustainability:A systematic review
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作者 Nicholas Manning Yingjie Li Jianguo Liu 《Geography and Sustainability》 CSCD 2023年第1期6-18,共13页
Complex sustainability issues in the Anthropocene,with rapid globalization and global environmental changes,are increasingly interlinked between not only nearby systems but also distant systems.Tobler’s first law of ... Complex sustainability issues in the Anthropocene,with rapid globalization and global environmental changes,are increasingly interlinked between not only nearby systems but also distant systems.Tobler’s first law of geog-raphy(TFL)states“near things are more related than distant things”.Evidence suggests that TFL is not infallible for sustainability issues.Recently,the integrated framework of metacoupling(MCF;human-nature interactions within as well as between adjacent and distant systems)has been applied to analyze the interactions between nearby and distant coupled human and natural systems simultaneously.However,previous work has been scat-tered and fragmented.It is crucial to understand the extent to which TFL and MCF apply across pressing issues in sustainability.Therefore,we reviewed and synthesized sustainability literature that used TFL and MCF across seven major topics:land change,species migration,tourism,trade,agricultural development,conservation,and governance.Results indicate MCF had a much broader applicability than TFL for these topics.The literature using MCF generally did not or likely did not obey TFL,especially in trade,governance,and agricultural de-velopment.In the TFL literature,most topics obeyed TFL,except for species migration and trade.The findings suggest the need to rethink and further test TFL’s relevance to sustainability issues,and highlight the potential of MCF to address complex interactions between both adjacent and distant systems across the world for global sustainability. 展开更多
关键词 Telecoupling SUSTAINABILITY Tobler’s First Law of geography Systematic review Metacoupling
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Evaluation of land suitability for Moringa oleifera tree cultivation by using Geospatial technology:The case of Dhidhessa Catchment,Abay Basin,Ethiopia
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作者 Mitiku Badasa Moisa Muleta Ebissa Feyissa +5 位作者 Indale Niguse Dejene Firdissa Sadeta Tiye Kiros Tsegay Deribew Zenebe Reta Roba Mengistu Muleta Gurmessa Dessalegn Obsi Gemeda 《Oil Crop Science》 CSCD 2023年第1期45-55,共11页
Land suitability analysis of Moringa oleifera tree cultivation is important to enhance its product,as the demand forthis tree for medicinal values and food sources is increasing worldwide.Therefore,this study aimed to... Land suitability analysis of Moringa oleifera tree cultivation is important to enhance its product,as the demand forthis tree for medicinal values and food sources is increasing worldwide.Therefore,this study aimed to assess suitableland for Moringa oleifera tree cultivation by using the integration of multi-criteria evaluation with geospatialtechnologies in the Dhidhessa catchment,western Ethiopia.Five parameters,namely:slope,land use and landcover(LULC),soil texture,land surface temperature,and rainfall data,were used in this study.The land suitabilityevaluation of Moringa oleifera is classified into three classes as highly suitable,moderately suitable,and notsuitable.The results revealed that,about 344.4 km2(12.2%)of the area is categorized into highly suitable,and2343.7 km2(83%)is moderately suitable for Moringa tree,whereas,137.2 km2(4.9%)is categorized as notsuitable for Moringa oleifera tree cultivation.Hence,based on the finding of the study,we suggested that farmers andother stakeholders can cultivate Moringa oleifera trees in the Dhidhessa catchment. 展开更多
关键词 Moringa tree Medicinal plant Overlay analysis AHP MCE
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Integrated Rice-Based Shrimp and Crabs Farming: Adaptation to Climate Change and Potential Mitigation of Global Warming in the Coastal Wetlands of Bangladesh
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作者 Muhammad Aslam Ali Shahroz Mahean Haque +7 位作者 Khalid Sohrawardi S. K. Fazlay Rabbi Shuvo Kumar Sarkar Hafsa Jahan Hiya Fakir Azmol Huda Sumon Malakar Mahjabeen Rahman Md. Shakir Ahammed 《Journal of Agricultural Chemistry and Environment》 2023年第3期223-237,共15页
Coastal agriculture is vulnerable to climate change, thereby may affect food production systems and food security in Bangladesh. Methane (CH4) emission from coastal wetlands rice farming is a major environmental conce... Coastal agriculture is vulnerable to climate change, thereby may affect food production systems and food security in Bangladesh. Methane (CH4) emission from coastal wetlands rice farming is a major environmental concern due to its global warming potential. Therefore, field experiments were conducted at the southern coastal region of Shyamnagar, Satkhira, to investigate the feasibility of Rice-Shrimp and Rice-Crabs mixed farming for adaptation to the changing climate and sustaining food production system. The experimental treatments were designed on rice-based diversified farming systems such as rice sole cropping with no NPKS + no soil amendments (T1), rice sole cropping following farmers’ practice (FP) without soil amendment (T2), rice sole cropping following FP with phosphogypsum (PG) amendment (T3), Rice-Shrimp mixed culture with PG amendment (T4), Rice-Crabs mixed culture with PG amendment (T5), Rice-Shrimp mixed culture + PG amendment with Spirulina (Cyanobacteria) inoculation (T6), and Rice-Crabs mixed culture + PG amendment with Spirulina inoculation (T7). A closed chamber technique was followed to collect gas samples from the rice paddy field and samples were analyzed by Gas Chromatograph. It was found that Rice-Shrimp (T6) and Rice-Crabs mixed farming (T7) practices significantly decreased GWPs compared to the rice sole cropping system. In the dry boro season, the maximum GWPs 4175 kg CO<sub>2</sub> eq. ha<sup>-1</sup> was recorded from rice sole cropping (T2), which was decreased by 30% and 36.7% under Rice-Shrimp (T6) and Rice-Crabs (T7) mixed farming practices, respectively. Furthermore, in the wet aman season, maximum GWP 4525 kg CO<sub>2</sub> eq. ha<sup>-1</sup> was recorded from rice sole cropping (T2), which was decreased by 33.0% and 38.8% under Rice-Shrimp and Rice-Crabs mixed farming, respectively. Rice grain yield was low under rice sole cropping (3500 kg/ha), which was increased by 11.0% and 14.7% under Rice-Shrimp mixed farming amended with PG and Spirulina (T6) during wet aman and dry boro seasons, respectively. The postharvest soil properties, such as soil organic matter content, redox potential value (Eh), and exchangeable K<sup>+</sup> and Ca<sup>2+</sup>, contents in soil increased significantly with Phosphogypsum and Spirulina applications, however, decreased Na<sup>+</sup> content and electrical conductivity (EC) eventually improved rice plants’ tolerance to salinity and enhanced overall productivity of Rice-Shrimp and Rice-Crabs mixed farming. Conclusively, the conversion of wetland mono rice cropping into mixed Rice-Shrimp and Rice-Crabs farming would be a feasible strategy to sustain rice aquaculture-based farming, ensure food security and mitigate GWPs in coastal wetlands ecosystem. 展开更多
关键词 Coastal Paddy SHRIMP CRABS SPIRULINA GWPs
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Bacteriological and Physicochemical Quality of Groundwater of Mbankomo Municipality(Center Region,Cameroon)
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作者 Murielle Patricia Mabou Tokam Antoine Tamsa Arfao +9 位作者 Fils Mamert Onana Ernest Koji Vanelle Lontchi Segnou Yves Poutoum Yogne Awawou Manouore Njoya Ornel Kadji Tchantcha Ahmadou Fadimatou Sylvie Chinche Belengfe Edith Brunelle Mouafo Tamnou Moïse Nola 《Journal of Environmental Science and Engineering(B)》 2023年第3期115-127,共13页
A study to evaluate the physico-chemical and bacteriological quality of groundwater was carried out in the commune of Mbankomo(Centre-Cameroon)at 4 wells and 4 springs during the period from March to August.The physic... A study to evaluate the physico-chemical and bacteriological quality of groundwater was carried out in the commune of Mbankomo(Centre-Cameroon)at 4 wells and 4 springs during the period from March to August.The physico-chemical parameters were measured by the standard method.Indicator bacteria of fecal contamination,namely HAB(Heterotrophic Aerobic Bacteria),total and faecal coliforms(Escherichia coli),and faecal streptococci were isolated by the surface spreading technique on PCA(Plate Count Agar),Endo and BEA(Bile Esculin Azide)agar respectively,and sulphite-reducing clostridia by the incorporation method on Tryptone Sulfite Cycloserine(TSC)agar.From a physico-chemical point of view,the groundwater in Mbamkomo is characterized by an average temperature(24.24±0.24°C);it is polluted with organic matter,acid and poorly mineralized.It was noted from a bacteriological point of view that these waters have a high and varied bacterial load with an average value of 100.8 × 10^(5) CFU/100 mL for coliforms,16.3 × 10^(5) CFU/100 mL for fecal streptococci,5.6 × 10^(5) CFU/100 mL for Escherichia coli and 4.8 ×10^(²)CFU/100 mL for Clostridium perfringens.These concentrations are all higher than the WHO(World Health Organization)standards which are set at 0 CFU/100 mL for coliforms,fecal streptococci and Clostridium perfringens and indicate fecal pollution of these waters.Escherichia coli cell densities were significantly correlated with dissolved oxygen in the water(r=0.510;p<0.05).The degradation of the quality of these waters is favored by their proximity to pollution sources,poor maintenance and poor protection of the wells.These waters,without any treatment,are not recommended for human consumption according to the standards of the WHO. 展开更多
关键词 GROUNDWATER physico-chemical quality bacteriological quality.
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Application of CEDA and ASPIC computer packages to the hairtail (Trichiurus japonicus) fishery in the East China Sea 被引量:14
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作者 王玉 刘群 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期92-96,共5页
Surplus-production models are widely used in fish stock assessment and fisheries management due to their simplicity and lower data demands than age-structured models such as Virtual Population Analysis. The CEDA (catc... Surplus-production models are widely used in fish stock assessment and fisheries management due to their simplicity and lower data demands than age-structured models such as Virtual Population Analysis. The CEDA (catch-effort data analysis) and ASPIC (a surplus-production model incorporating covariates) computer packages are data-fitting or parameter estimation tools that have been developed to analyze catch-and-effort data using non-equilibrium surplus production models. We applied CEDA and ASPIC to the hairtail (Trichiurus japonicus) fishery in the East China Sea. Both packages produced robust results and yielded similar estimates. In CEDA, the Schaefer surplus production model with log-normal error assumption produced results close to those of ASPIC. CEDA is sensitive to the choice of initial proportion, while ASPIC is not. However, CEDA produced higher R 2 values than ASPIC. 展开更多
关键词 渔业管理 中国东海 ELECTRONICS 电脑 应用 带鱼 结构模型 参数估计
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Evaluating Conservation Effectiveness of Nature Reserves Established for Surrogate Species:Case of a Giant Panda Nature Reserve in Qinling Mountains,China 被引量:12
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作者 XU Weihua Andrés VIA +4 位作者 QI Zengxiang OUYANG Zhiyun LIU Jianguo LIU Wei WAN Hui 《Chinese Geographical Science》 SCIE CSCD 2014年第1期60-70,共11页
Many nature reserves are established to protect the habitat needs of particular endangered species of interest but their effectiveness for protecting other species is questionable.In this study,this effectiveness was ... Many nature reserves are established to protect the habitat needs of particular endangered species of interest but their effectiveness for protecting other species is questionable.In this study,this effectiveness was evaluated in a nature reserve network located in the Qinling Mountains,Shaanxi Province,China.The network of reserves was established mainly for the conservation of the giant panda,a species considered as a surrogate for the conservation of many other endangered species in the region.The habitat suitability of nine protected species,including the giant panda,was modeled by using Maximum Entropy(MAXENT)and their spatial congruence was analyzed.Habitat suitability of these species was also overlapped with nature reserve boundaries and their management zones(i.e.,core,buffer and experimental zones).Results show that in general the habitat of the giant panda constitutes a reasonable surrogate of the habitat of other protected species,and giant panda reserves protect a relatively high proportion of the habitat of other protected species.Therefore,giant panda habitat conservation also allows the conservation of the habitat of other protected species in the region.However,a large area of suitable habitat was excluded from the nature reserve network.In addition,four species exhibited a low proportion of highly suitable habitat inside the core zones of nature reserves.It suggests that a high proportion of suitable habitat of protected species not targeted for conservation is located in the experimental and buffer zones,thus,is being affected by human activities.To increase their conservation effectiveness,nature reserves and their management zones need to be re-examined in order to include suitable habitat of more endangered species.The procedures described in this study can be easily implemented for the conservation of many endangered species not only in China but in many other parts of the world. 展开更多
关键词 大熊猫自然保护区 濒危物种 秦岭北麓 中国 大熊猫栖息地 自然保护区网络 保护物种 育成
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Spatial and seasonal distribution of intertidal macrobenthos with their biomass and functional feeding guilds in the Naf River estuary, Bangladesh 被引量:4
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作者 Md. Abu NOMAN MAMUNUR Rashid +1 位作者 M SHAHANUL Islam M. Belal HOSSAIN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第3期1010-1023,共14页
The Naf River estuary is one of the most productive ecological ecosystems in Bangladesh providing an important feeding area for fishes and other aquatic animals.However,detailed information on macrobenthic communities... The Naf River estuary is one of the most productive ecological ecosystems in Bangladesh providing an important feeding area for fishes and other aquatic animals.However,detailed information on macrobenthic communities is rarely available in this area.Our study focused on the seasonal and spatial variability of macrobenthic community structure with their biomass and functional guilds.In total,fortyseven taxa were identified under nine major groups and seven functional feeding guilds.Among macrobenthic taxa,Polychaeta was dominant in both seasons and all over the estuary contributing 60%of total benthos.The mean abundance of macrobenthos was higher during the pre-monsoon(2 972±1 994 inds./m^2)than the monsoon(1 572±361 inds./m^2)being maximum at mid-estuary region and minimum at upper and lower estuary regions.Of the diversity indices,density(P=0.01,P=0.003),the number of taxa(P=0.000 3,P=0.000 9)and Margalef′s Index(P=0.000 4,P=0.001)of macrobenthos were significantly different among stations and seasons.Shannon-Weiner index(P=0.009,P=0.12)and Pielou’s evenness index(P=0.03,P=0.14)had significant differences among stations but not among seasons.Cluster analysis suggested that distribution of macrofauna is strongly influenced by seasonality.Among the feeding types,carnivorous were found to be dominant at the upper and mid-estuarine regions,and herbivorous were at lower estuarine regions.Carnivorous species were dominant in both seasons.Omnivores have shown to be the most abundant feeding type in terms of biomass though herbivores were highest during monsoon. 展开更多
关键词 MACROBENTHOS seasonal VARIATION SPATIAL VARIATION feeding GUILDS BIOMASS NAF River estuary
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Ingestion of Brachionus plicatilis under different microalgae conditions 被引量:3
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作者 周文礼 唐学玺 +3 位作者 乔秀英 王悠 王仁君 冯蕾 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期473-479,共7页
The effects of four microalgae,Chlorella vulgaris,Platymonas helgolandicavar,Isochrysis galbana,and Nitzschia closterium on the grazing and filtering rates of the marine rotifer,Brachionus plicatilis,were evaluated un... The effects of four microalgae,Chlorella vulgaris,Platymonas helgolandicavar,Isochrysis galbana,and Nitzschia closterium on the grazing and filtering rates of the marine rotifer,Brachionus plicatilis,were evaluated under laboratory conditions.The grazing rates in separate cultures of the four microalga were as follows:C.vulgaris > P.helgolandicavar > I.galbana > N.closterium.However,the filtering rates occurred in the following order:P.helgolandicavar > N.closterium > C.vulgaris > I.galbana.A mixed diets experiment revealed that P.helgolandicavar was the preferred diet of B.plicatilis.In addition,the grazing rate of B.plicatilis increased gradually as the density of the microalgae increased,until concentrations of 2.5×106 cells mL-1 for C.vulgaris and 1.5×106 cells mL-1 for I.galbana were obtained.Furthermore,the filtering rate increased slightly when the density of the microalgae was low,after which it declined as the microalgal density increased.The grazing rates of B.plicatilis were as follows during the different growth phases:stationary phase > exponential phase > lag phase > decline phase.Additionally,the filtering rates during the growth phases were:exponential phase > lag phase > stationary phase > decline phase.The results of this study provide foundational information that can be used to explore the optimal culture conditions for rotifers and to promote the development of aquaculture. 展开更多
关键词 轮虫 藻类 新月菱形藻 实验室条件 等鞭金藻 摄食 生长阶段 放牧率
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Application of a Delay-Difference Model for the Stock Assessment of Southern Atlantic Albacore(Thunnus alalunga) 被引量:2
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作者 ZHANG Kui LIU Qun KALHORO Muhsan Ali 《Journal of Ocean University of China》 SCIE CAS 2015年第3期557-563,共7页
Delay-difference models are intermediate between simple surplus-production models and complicated age-structured models. Such intermediate models are more efficient and require less data than age-structured models. In... Delay-difference models are intermediate between simple surplus-production models and complicated age-structured models. Such intermediate models are more efficient and require less data than age-structured models. In this study, a delay-difference model was applied to fit catch and catch per unit effort(CPUE) data(1975–2011) of the southern Atlantic albacore(Thunnus alalunga) stock. The proposed delay-difference model captures annual fluctuations in predicted CPUE data better than Fox model. In a Monte Carlo simulation, white noises(CVs) were superimposed on the observed CPUE data at four levels. Relative estimate error was then calculated to compare the estimated results with the true values of parameters α and β in Ricker stock-recruitment model and the catchability coefficient q. α is more sensitive to CV than β and q. We also calculated an 80% percentile confidence interval of the maximum sustainable yield(MSY, 21756 t to 23408 t; median 22490 t) with the delay-difference model. The yield of the southern Atlantic albacore stock in 2011 was 24122 t, and the estimated ratios of catch against MSY for the past seven years were approximately 1.0. We suggest that care should be taken to protect the albacore fishery in the southern Atlantic Ocean. The proposed delay-difference model provides a good fit to the data of southern Atlantic albacore stock and may be a useful choice for the assessment of regional albacore stock. 展开更多
关键词 差分模型 南大西洋 金枪鱼 应用 评估 股票数据 时滞
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Molecular detection of microbial communities associated with Microcystis vs Synechococcus dominated waters in Tianjin,China 被引量:4
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作者 霍达 陈友信 +3 位作者 刘萍 李一鸣 乔之怡 李仁辉 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第4期1145-1156,共12页
Harmful cyanobacterial blooms cause many ecological disasters worldwide. During the development of cyanobacterial blooms, the diversity and domination of cyanobacterial taxa are of a particular concern. In this study,... Harmful cyanobacterial blooms cause many ecological disasters worldwide. During the development of cyanobacterial blooms, the diversity and domination of cyanobacterial taxa are of a particular concern. In this study, the microbial community structure within a water system, such as in Yuqiao Reservoir and Haihe River in Tianjin City, China, was compared by using next-generation sequencing. A total of 5 001 operational taxonomic units were obtained and clustered from filtered 16 S rDNA V3–V4 region sequences. The cyanobacterial and microbial structures greatly differed in these two water areas. Microcystis was dominant in Yuqiao, whereas Synechococcus was dominant in Haihe. Proteobacteria species were dominant among all detected samples. The relative abundances of Bacteroidetes and Planctomycetes were higher in Yuqiao Reservoir than in Haihe River, whereas Firmicutes and Verrucomicrobia were relatively abundant in Haihe River. Further analyses indicated that the domination of both cyanobacteria was strongly related to several environmental factors, such as total nitrogen, total phosphorus, and dissolved oxygen, reflecting the role of trophic states in shaping the dominance of cyanobacterial taxa. The present study provided the example for Microcystis and Synechococcus dominance along a cyanobacterial bloom in north China. Applying highthroughput sequencing could offer a wide field of vision in analyzing microbial community structures. 展开更多
关键词 蓝藻 细菌 湖泊 生态系统
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Differentiation of coral trout (Plectropomus leopardus) based on an analysis of morphology and complete mitochondrial DNA: Are cryptic species present? 被引量:2
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作者 CAI Xiaopeng QU Meng +4 位作者 DING Shaoxiong WANG Hangjun WANG Hongjie HU Luyi SU Yongquan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第6期40-46,共7页
Two morphotypes of Plectropomus leopardus have been identified; morphometric and meristic analyses show that there is no diagnostic difference between them. A difference in color pattern was the most ap- propriate phe... Two morphotypes of Plectropomus leopardus have been identified; morphometric and meristic analyses show that there is no diagnostic difference between them. A difference in color pattern was the most ap- propriate phenotypic character with which to distinguish between the two morphotypes. Complete mito- chondrial DNA sequencing, however, indicated a clear difference between the two morphotypes. Barcoding analysis revealed no significant difference (P〉0.05) in CO1 or ND2 divergence among intramorphotypic individuals, even between geographically separated populations, whereas the intermorphotypic CO1 and ND2 divergences were large enough (averaging 0.95% for CO1 and 1.37% for ND2) to clearly discriminate between the two morphotypes. The color pattern difference, geographical distribution, together with the mtDNA and barcode sequencing data, suggest that the two morphotypes should be of two subspecies or even two species. 展开更多
关键词 Plectropomus leopardus MORPHOTYPE omplete mitochondrial DNA BARCODING
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Hexadecanoic acid-enriched extract of Halymenia durvillei induces apoptotic and autophagic death of human triple-negative breast cancer cells by upregulating ER stress 被引量:4
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作者 Kant Sangpairoj Rapeewan Settacomkul +6 位作者 Tanapan Siangcham Krai Meemon Nakorn Niamnont Nilubon Sornkaew Montakan Tamtin Prasert Sobhon Pornpun Vivithanaporn 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2022年第3期132-140,共9页
Objective:To investigate the effect of the hexane solvent fraction of Halymenia durvillei(HDHE)on triple-negative breast cancer.Methods:The phytochemical profile of HDHE was investigated by GC-MS.The cytotoxicity of H... Objective:To investigate the effect of the hexane solvent fraction of Halymenia durvillei(HDHE)on triple-negative breast cancer.Methods:The phytochemical profile of HDHE was investigated by GC-MS.The cytotoxicity of HDHE against MDA-MB-231 cells was determined.The apoptotic and autophagic effects of HDHE were analyzed.The expression of molecular markers controlling apoptosis,autophagy,DNA damage,and endoplasmic reticulum(ER)stress was determined.Results:HDHE contains a mixture of fatty acids,mainly hexadecanoic acid.HDHE at a cytotoxic concentration induced apoptotic death of MDA-MB-231 cells through mitochondrial membrane dysfunction,and induction of apoptosis markers,and increased the expression of proteins related to DNA damage response.HDHE also induced the expression of LC-3,a marker of autophagic cell death at a cytotoxic concentration.Moreover,HDHE modulated the expression of ER stress genes.Conclusions:The hexadecanoic acid-enriched extract of Halymenia durvillei promotes apoptosis and autophagy of human triple-negative breast cancer cells.This extract may be further explored as an anticancer agent for triple-negative breast cancer. 展开更多
关键词 Halymenia durvillei Triple-negative breast cancer APOPTOSIS AUTOPHAGY Endoplasmic reticulum stress Red algae Hexadecanoic acid
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Hydrobiological variables as a regulatory factor on the abundance of heterotrophic flagellates in an urban pond 被引量:1
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作者 BEGUM Moni JEWEL Md.Abu Sayed +1 位作者 HAQUE Md.Ayenuddin KHATUN Mst.Samsad 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第3期1030-1036,共7页
The seasonal abundance of flagellates has been monitored over a period of 1 year from December 2013 to November 2014(divided into 4 conjugative seasons namely winter,spring,summer,and autumn)in an experimental pond lo... The seasonal abundance of flagellates has been monitored over a period of 1 year from December 2013 to November 2014(divided into 4 conjugative seasons namely winter,spring,summer,and autumn)in an experimental pond located in Rajshahi City Corporation area,Bangladesh.To our knowledge,this study is the fi rst to shed light on the occurrence and possible interrelationships among heterotrophic flagellates(HF),bacteria and zooplankton in Bangladesh and the result obtained by this study will be beneficial for similar water ecosystem all over the world.Standard methods were used to determine the prescribed hydrological parameters and zooplankton cell density.Maximum HF abundance(14 346.00 cells/mL)was found in the spring and the minimum(5 215.00 cells/mL)occurred in the summer.Inverse to HF,significantly(P<0.05)higher zooplankton abundance was found during the winter(782.00±47.62 cells/mL)and the lowest value was found in the autumn(448.00±39.15 cells/mL).Whereas similar to the HF,total bacterial abundance was significantly higher during the spring((2.25±1.05)×10^5 cells/mL)and lower in the summer((0.79±0.06)×10^5 cells/mL).Multivariate analyses(ANOSIM and MDS)have shown significant seasonal differences for cell numbers where MDS ordination plot and cluster analysis based on similarity in the genera abundance of HF revealed overlapping condition between winter and spring.Canonical correspondence analysis(CCA)also showed a distinct separation among the genera based on the prevailing hydrological situation and indicated that temperature,pH,BOD5,and NO3^-were the most important environmental variables in determining the observed variation in HF community structure.Among the biological factors,zooplankton showed negative but total bacteria were positively correlated with HF abundance. 展开更多
关键词 HETEROTROPHIC FLAGELLATES ABUNDANCE hydrobiological factors URBAN POND
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Phytoplankton Index of Biological Integrity (P-IBI) in Several Marshes, Southern IRAQ 被引量:5
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作者 Bahram K. Maulood Abdul Hameed M. Jawad Alobaidy +2 位作者 Azhar Alsaboonchi Haider S. Abid Ghasak S. Alobaidy 《Journal of Environmental Protection》 2011年第4期387-394,共8页
Indices of Biological Integrity (IBIs) are being increasingly used as useful and direct tools for assessing general health of aquatic ecosystems. Although such ecosystems in Iraq, especially the southern marshes, unde... Indices of Biological Integrity (IBIs) are being increasingly used as useful and direct tools for assessing general health of aquatic ecosystems. Although such ecosystems in Iraq, especially the southern marshes, underwent severe alterations during the last two decades, including extensive desiccation in the 1990s, such tools are largely lacking. Phytoplankton Index of Biological Integrity (P-IBI) was developed from data collected seasonally from 2005 up to 2007 in different sites of the southern marshes of Iraq to evaluate the trend of these ecosystems based on phytoplankton data. Ten metrics were selected for measuring P-IBI for the first time in Iraq as a proposed project from Nature Iraq and Twin Rivers Institute, American University of Iraq-Sulaimani. Although generally fluctuated both spatially and temporally, mean P-IBI scores showed better conditions in Al Hawizeh marsh (Good) as compared to the Central and West & East Al Hammar marshes (Fair to Good). However, the results generally indicated evidence of improvement at the Central and West & East Al Hammar marshes, whereas no recovery of the status of water was evident throughout the data obtained at Al Hawizeh marsh. Values were generally higher in winter. These observations clearly reflect the relative stability of the Hawizeh marsh ecosystem which was not subject to the desiccation process in the 1990s, while the severely dried systems of the Central and Hammar marshes are showing positive responses to the restoration efforts that were started after 2003. Among the ten metrics comprising the index, relative abundance of diatoms had the most prominent effect on the P-IBI value in the three marshes. Metrics such as chlorophyll- a concentration and relative abundance of Cyanophyta and Chlorophyta also played a significant role in determining the index value. Continuous monitoring based on the selection of the most suitable metrics is recommended. 展开更多
关键词 IBI Nature Iraq MARSHES AQUATIC ECOLOGY
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