Aquatic Ecosystem Health and Management最新文献

{"title":"Invasion meltdown and burgeoning threats of invasive fish species in inland waters of India in the era of climate change","authors":"Ashutosh Kumar Singh, S. Srivastava","doi":"10.14321/aehm.024.03.04","DOIUrl":"https://doi.org/10.14321/aehm.024.03.04","url":null,"abstract":"Cyprinus carpio, Oreochromis niloticus and Clarias gariepinus are the most abundantly captured invasive fish species in the mid-stretch of the Ganga river. Fish yield and biomass data based on mean abundance by weight was calculated using algorithms and spatio-temporal population dynamics model for future prediction of these invasive fish species. Temporal biomass forecast based on mean abundance by wieght for the period from 2020 to 2029 was determined. The findings of this study predicted fish yield of 176 ±16.33 kg km-1 day-1 C. carpio and 55.43 ± 6.4 kg km-1 day-1 O. niloticus during 2029 which might result into 117.87% and 116.9% rise in temporal biomass of Common Carp and Tilapia respectively in a decade's time while 139.2% rise in temporal biomass was predicted for the invasive African catfish. The yield of invasive Common Carp, Tilapia and African Catfish was correlated with rainfall and temperature data using ANOVA and we found that variance was F=1.36; p=0.263 for C. carpio; F=1.60; p=0.326 for O. niloticus and F=1.63; p=0.101 for C. gariepinus, indicating that variance was very close for Tilapia and African Catfish. The observed values of variance indicated that climatic changes had more impact to these two species than to the Common Carp. The concrete and forecast values were calculated considering 95% lower and upper level of confidence, which was significant (p<0.05) and the annual regression was found to be p<0.464, p<0.419 and p<0.499 for C. carpio, O. niloticus and C. gariepinus, respectively. Further, interactive performance of invaded C. carpio, O. niloticus and C. gariepinus was also assessed for understanding invasion meltdown. The results of mean abundance by weight based yield forecast of invaded Tilapia, Common Carp and African Catfish for the period of 2020 to 2029 suggest a stable production in the Ganga River in years to come. It also manifests a positive pattern of invasion in the times of climate change displaying invasion meltdown. This suggests increased pressures of fish invasions on temporal and spatial scales, and imposing new management challenges for freshwater ecosystems.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121796369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Response of extreme significant wave height to climate change in the South China Sea and northern Indian Ocean","authors":"Yao Luo, H. Shi, Weiqiang Wang","doi":"10.14321/aehm.024.03.12","DOIUrl":"https://doi.org/10.14321/aehm.024.03.12","url":null,"abstract":"The frequency of extreme wave events is increasing with climate change. The temporal and spatial variations of extreme wave height affect both human livelihood and the usage of ocean resources. The South China Sea and northern Indian Ocean both support coastal communities of high population density, with varied terrain structures and extreme wind and wave systems. This study focuses on the temporal and spatial variations of the extreme significant wave height in the South China Sea and northern Indian Ocean. Using nonstationary generalized extreme value analysis, trends for a 100-year return period of significant wave height were obtained for both. The most rapid increase in the 100-year return was found to be 0.015 m yr-1 in the northern South China Sea and in the Arabian Sea; however, the 100-year return significant wave height fell in the mouth of the Bay of Bengal. After analyzing the possible causes and influence factors, we found that the increase in significant wave height in the northern South China Sea was dominated by local wind-waves and similarly, the Arabian Sea was affected by swell. The NINO3.4 index shows good correlation with the significant wave height in the northern South China Sea because typhoons are related to NINO3.4 in this area. The trends of the extreme wave height in the Arabian Sea and southern Bay of Bengal have good correlations with the South Asian summer monsoon index.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123361352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impacts of climate change and adaptations in shrimp aquaculture: A study in coastal Andhra Pradesh, India","authors":"M. Muralidhar, M. Kumaran, M. Jayanthi, J. S. Dayal, J. Kumar, R. Saraswathy, A. Nagavel","doi":"10.14321/aehm.024.03.05","DOIUrl":"https://doi.org/10.14321/aehm.024.03.05","url":null,"abstract":"Shrimp aquaculture in India is synonymous with coastal aquaculture. Like other agricultural activities, it appropriates a wide range of environmental goods and services, and is vulnerable to impacts of climate change as the cultured animals are sensitive to various kinds of biotic and abiotic stressors. Climate change affects the shrimp aquaculture directly by extreme weather events and seasonal variations, and indirectly alter the primary and secondary productivity, structure and composition of the ecosystems or by influencing the availability of fishmeal, fish oil and other goods and services required for aquaculture farmers. The perceptions of farmers on the impacts of climate change on shrimp aquaculture in inland and coastal areas of Krishna District, Andhra Pradesh are discussed. Cyclone and flood were perceived by all the farmers, whereas irregular season, high temperature, heavy rain and drought were perceived by 79, 89, 91 and 5 % of farmers, respectively. Environmental, biological, and economic impacts of climate change drivers on aquaculture indicated 20 to 30 % loss due to seasonal variations and 50 to 100% loss due to extremely heavy rainfall, flood and cyclones. The economic risk rating was high with flood followed by the cyclone and the magnitude was more in coastal areas compared to inland areas. There is no universally applicable list of adaptation measures and need to be evaluated for individual aquaculture systems. Autonomous and planned adaptation measures to be implemented by farmers, researchers and policymakers are discussed for climate-resilient aquaculture. Planned adaptive measures are either at the primary level or non-existence, hence policy initiatives are required to formulate planned adaptive measures to enhance the adaptive capacity of the farmers.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114636740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of climate change-induced challenges on fisheries in the North Eastern Region of India and the way ahead","authors":"B. Borah","doi":"10.14321/aehm.024.03.11","DOIUrl":"https://doi.org/10.14321/aehm.024.03.11","url":null,"abstract":"India's North Eastern Region comprises eight land-locked states and has a total population approaching 46 million, made up of approximately 220 ethnic communities. A high demand for fish prevails in the region as 90–100% of the population prefers fish in their daily diet. The region faces climate change-related issues at various levels and with a range of impacts on the inland fisheries sector. The period 1951 to 2010 saw a significant increase in annual mean temperature in several states of the region (Arunachal Pradesh, Assam, Manipur, Sikkim, Mizoram, and Tripura). The highest increase in annual mean temperature was recorded in Sikkim (+0.05 °C yr-1) followed by Manipur (+0.03 °C yr-1). Significant changes in annual rainfall pattern were also recorded during the same time period in the region: four of the eight states (Assam, Arunachal Pradesh, Sikkim, and Nagaland) experienced a decreasing trend, and the remaining four (Meghalaya, Manipur, Tripura, and Mizoram) an increasing trend. The highest increase in annual rainfall was recorded in Meghalaya (+14.68 mm yr-1) during this period. The change in seasonal trend of mean temperature and the erratic rainfall pattern in the region have had profound impacts on the traditional fisheries of the region. This study outlines these impacts and suggests potential adaptation actions that may be implemented to cope with climate change.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131684428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Invasion and potential risks of introduced exotic aquatic species in Indian islands","authors":"C. Raghunathan, T. Mondal, K. Chandra","doi":"10.14321/aehm.024.02.11","DOIUrl":"https://doi.org/10.14321/aehm.024.02.11","url":null,"abstract":"India is endowed with a wide range of ecosystems, of which oceanic island ecosystems viz. Andaman and Nicobar and Lakshadweep are unique and ecologically fragile because of the high degree of endemism in species composition. Altogether 25 species under different faunal groups such as cnidarians, polychaetes, cirripedes, mollusks, and ascidians are reported as invasive species in Indian islands, of which 24 species are found in Andaman and Nicobar Islands, while 4 species are available in Lakshadweep. Ship-mediated invasions, especially ballast water discharge and ship-hull fouling, are the major source of invasions as these islands are located in the vicinity of the international sea route. In the present paper, we have represented these non-native species of fauna and flora to discriminate and identify them as non-native or invasive. This study deals with the diversity and distribution of aquatic invasive species in islands and their detrimental impact on the island ecosystem.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129346278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bioaccumulation of trace elements in migratory waterbirds at two wetlands of Indus river","authors":"Muhammad Ahsan Ashraf, Z. Ali","doi":"10.14321/aehm.024.02.15","DOIUrl":"https://doi.org/10.14321/aehm.024.02.15","url":null,"abstract":"Waterbirds are used as a bioindicator for analyzing wetland health because they are very sensitive to changes in ecosystems at the nutrient level and through exposure to pollutants. In the present study, bioaccumulation of trace elements (Cu, Zn, Ni, Pb, Co, Cd, and Mn) was investigated in Common Coot Fulica atra, Gadwall Anas strepera, and Eurasian Teal Anas crecca at Taunsa barrage and Chashma barrage located on Indus River, Punjab, Pakistan. Samples of water, sediments, and waterbirds tissues were collected during autumn 2018 and the spring of 2019. Metal concentrations were assessed by using a flame atomic absorption spectrophotometer (Thermo Scientific iCE 3000 Series). We found that the maximum bioaccumulation in birds was of cadmium. Order of metal accumulation was Cd > Pb > Zn > Co > Mn > Cu > Ni (Common Coot) and Cd > Pb > Zn > Co > Cu > Ni > Mn (Gadwall and Eurasian Teal) at Taunsa barrage. At Chashma barrage metal accumulation order was Cd > Zn > Pb > Co > Cu > Mn > Ni (Common Coot), Cd > Zn > Pb > Cu > Co > Ni > Mn (Gadwall) and Cd > Zn > Pb > Co > Cu > Ni > Mn (Eurasian Teal). A. crecca was the species in which the most of the trace elements (Cu, Ni, Pb, Co, and Mn) were accumulated at Taunsa barrage, while at Chashma barrage Zn, Pb, Cd, and Co accumulated in F. atra. Zn, Pb and Cd (avg. > 10) had a high bioaccumulation ratio and Co, Cu, Ni, and Mn (avg. < 10) had low bioaccumulation ratio. When tissues were compared for accumulation, the highest concentrations were observed in the intestine followed by gizzard, probably because of the feeding habits of these waterbirds.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116591136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial assemblage and interference competition of introduced Brown Trout (Salmo trutta) in a Himalayan river network: Implications for native fish conservation","authors":"Aashna Sharma, V. K. Dubey, J. A. Johnson, Y. K. Rawal, K. Sivakumar","doi":"10.14321/aehm.024.02.07","DOIUrl":"https://doi.org/10.14321/aehm.024.02.07","url":null,"abstract":"Often regarded as a potential threat to the native fish fauna worldwide, the Brown Trout (Salmo trutta), has successfully established its population in the majority of the Himalayan rivers post its introduction dating back to the eighteenth century. Over the years, the species has gained infamy as a sport fish and is considered a profitable source of income to the locals ensuing a heightened propagule pressure due to lack of appropriate management actions. No comprehensive study has been conducted to date in order to understand the mechanism by which the Brown Trout poses threat to the native fish populations. Through the present study, we could assess its competition with the native Snow Trout (Schizothorax richardsonii) to understand the spatial assemblage of both the species across space in Tirthan, a pristine high-altitude river of the western Himalaya. River Tirthan is one of the major tributaries of River Beas traversing for most of its stretch within the protected boundaries of the Great Himalayan National Park Conservation Area. A total of 108 sampling points were chosen from confluence to origin of rivers/streams, ranging from 989 to 3677msl. A total of 28 explanatory variables were recorded at each point. Overall, the Brown Trout adults were found to be greater in relative abundance (66.1%) than the Snow Trout adults (33.9%). The fingerlings of Snow Trout on the other hand, were distinctively high in relative abundance (61.9%) than those of the invasive Brown Trout (38.1%). Non-native trout showed higher abundance in the higher stream orders i.e. in the main streams while natives mostly restricted themselves to the lower order streams. Redundancy analysis (RDA) for species and environmental covariates resulted in 40.75% of constrained variance with higher eigen values for Redundancy analysis1 and Redundancy analysis2. Ward's minimum variance clustering of Hellinger transformed data revealed sites agglomerating into six reasonable distinct subgroups with respect to species abundances. Immature individuals of non-native and native trout used similar habitat conditions, but they differed in using habitats at adult stage. Our results show a competitive dominance of Brown Trout in terms of higher abundance and maximum space utilization that highlight an urgent action for preventing its introductions to new areas. We recommend a national policy of ‘The Indian Invasive Species Act’ and management level interventions to control overstocking in the areas of established population.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124537283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"State of aquatic invasive species in tropical India: An overview","authors":"A. Singh","doi":"10.14321/aehm.024.02.05","DOIUrl":"https://doi.org/10.14321/aehm.024.02.05","url":null,"abstract":"India, a megadiverse tropical country is grappling with the rising trend of aquatic invasions. Out of 532 introduced non-native fish, 16 species of freshwater aquaculture and aquarium were assessed invasive by using a risk assessment protocol, ‘Fish Invasiveness Screening Test’. Six major identified invasion pathways of the aquatic invasive species were inadvertent or deliberate releases, escapes, contaminants from hatcheries, river corridors, stowaways and unaided introductions. Invasion mechanism further elucidated the factors promoting successful invasion in freshwater ecosystems. For predictive future performance of invasive fish, the concrete and predictive values based on mean abundance by weight was calculated. Over 28.67% and 29.02 % persistent increased yield of the invasive Tilapia and Common Carp respectively was predicted in the Ganga river in the coming decades. Single species Tilapia invasion facilitated multiple species fish invasion, manifesting in invasion meltdown. The trophic changes due to fish invasion exhibited biotic homogenization with trophic downgrading. Aquatic invasive species were found highly competitive interacting with native species causing serious biodiversity loss, health hazards, and economic damage consequently affecting the ecosystem services. In spite of available regulatory approaches and guidelines to manage aquatic invasive species, fish invasion has been on the rise. This paper suggests modifications and stringent implementation of the existing regulatory mechanisms besides adopting linkages, cutting-edge research on invasion science and modern molecular containment tools for effective management.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124399588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Classification of Typha-dominated wetlands using airborne hyperspectral imagery along Lake Ontario, USA","authors":"G. Suir, Douglas A. Wilcox, M. Reif","doi":"10.14321/aehm.024.02.18","DOIUrl":"https://doi.org/10.14321/aehm.024.02.18","url":null,"abstract":"Shoreline wetlands along Lake Ontario are valuable, multi-functional resources that have historically provided large numbers of important ecosystem goods and services. However, alterations to the lake's natural hydrologic regime have impacted traditional meadow marsh in the wetlands, resulting in competition and colonization by dense and aggressive Typha angustifolia and Typha x glauca (Cattails). The shift to a Typha-dominated landscape resulted in an array of negative impacts, including increased Typha density, substantial decreases in plant species richness and diversity, and altered habitat and changes in associated ecosystem services. Successful long-term adaptive management of these wetland resources requires timely and accurate monitoring. Historically, wetland landscapes have been surveyed and mapped using field-based surveys and/or photointerpretation. However, given their resource- and cost-intensive nature, these methods are often prohibitively time- and labor-consuming or geographically limited. Other remote sensing applications can provide more rapid and efficient assessments when evaluating wetland change trajectories or analyzing direct and indirect impacts across larger spatial and temporal scales. The primary goal of this study was to develop and describe methodology using U.S. Army Corps of Engineers National Coastal Mapping Program hyperspectral imagery, light detection and ranging data, and high-spatial resolution true-color imagery to provide updated wetland classifications for Lake Ontario coastal wetlands. This study used existing field-collected vegetation survey data (Great Lakes Coastal Wetland Monitoring Program), ancillary imagery, and existing classification information as training data for a supervised classification approach. These data were used along with a generalized wetland schema (classes based on physical and biological gradients: elevation, Typha, meadow marsh, mixed emergent, upland vegetation) to generate wetland classification data with Kappa values near 0.85. Ultimately, these data and methods provide helpful knowledge elements that will allow for more efficient inventorying and monitoring of Great Lake resources, forecasting of resource condition and stability, and adaptive management strategies.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127566363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Management strategies to regulate the introduction of exotic ornamental fish, the silent invaders of freshwater ecosystems in India","authors":"T. T. A. Ajith Kumar, K. Lal","doi":"10.14321/aehm.024.02.14","DOIUrl":"https://doi.org/10.14321/aehm.024.02.14","url":null,"abstract":"Ornamental fish culture and aquarium keeping have become a booming sector worldwide. It has been observed that a number of stakeholders are involved in introducing exotic ornamentals in India as well, as the takers are interested on variants and new species. Most of the exotic ornamental fishes are also being domesticated in India, since the demand is readily fulfilled through adequate supply to the hobbyists. This sector provides livelihood option to many people and helps to earn millions of dollars to our country every year, however, the invasion of exotic ornamentals in our natural water bodies needs to be assessed, monitored and controlled with due attention as it is a staid menace to our biodiversity. Around 400 species / variants of exotic freshwater ornamentals and around 100 exotic marine ornamental species including invertebrates are found to have introduced in the trade. It is significant to note that an apparent violation in the trade is taking place by concealing the Government of India approval, which is given only for 92 species / variants of fishes for import. Further, as some of the freshwater ornamental fishes currently available in the aquarium trade have invaded through natural water bodies, their impacts need to be studied in detail. To deal with the situation, the proper precautionary approach should be implemented by adopting measures after having proper quarantine, meticulous risk analysis and strategic prevention methods as well. Combined efforts of industry stakeholders with different government agencies, academic and research institutions is required and a suitable protocol has to be formulated for permissible import, sustainable production, supply and management.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130928417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}