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A new species of nemacheilid loach, Schistura sonarengaensis sp. nov., is described from three cave-dwelling populations (Barak-Surma-Meghna drainage) in the South Garo Hills district of Meghalaya, India. The new species possesses prominent eyes but is easily distinguished from all the congeners of the genus Schistura from Barak-Surma-Meghna and adjacent rivers drainages of northeast Indian (except S. syngkai) in having 13-26 vertically elongated to circular mid-lateral black blotches (brownish in life) overlayered on a grayish-black mid-lateral stripe on a dull white or pale-beige (golden brown in life) body. However, it can be easily distinguished from S. syngkai in having a complete (vs. incomplete) lateral line with more 72-89 (vs. 19-42) lateral-line pored scales, greater pre-dorsal length (48.5-53.1 vs. 41.9-44.1 %SL), a wider body at dorsal-fin origin (11.3-16.7 vs. 9.4-10.3 %SL), greater dorsal (18.1-21.1 vs. 15.1-17.0 %SL) and lateral (20.9-24.1 vs. 17.4-18.9 %SL) head length, a wider head (14.5-18.5 vs. 11.6-13.3 %SL), and moderately forked (vs. emarginated) caudal fin. Further, molecular analysis confirms the distinctiveness of S. sonarengaensis sp. nov. from its congeners found in northeast India by significant divergences with uncorrected genetic distance ranging from 3.7% to 17.3% in the mitochondrial cytochrome c oxidase subunit I (COI) gene dataset. The phylogenetic position of the new species with its sister species was evaluated using maximum likelihood and Bayesian analysis. The species delimitation approaches assemble species by automatic partitioning (ASAP) and Poisson tree processes (PTP) utilized for testing species assignments consistently identified our test group as a distinct species from its sister species. Although the new species lacks typical morphological adaptations usually associated with a subterranean life, such as complete absence (or vestigial presence) of eyes and pigmentation, it exhibits a reduction of pigmentation when compared to the epigean congeners.
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The concept of "state fishes of India" highlights the importance and significance of the prioritized fish species distributed across various states within the country. This review article systematically documents the current status of state fishes from various perspectives, identifies the prevailing knowledge gaps, and also highlights the issues and strategic plans essential for the conservation and sustainable utilization of these valuable genetic resources. A total of 8357 publications were checked for the consolidated information on state fish species, and the appropriate items were selected under eight categories: biology, physiology and nutrition, aquaculture, habitat and environmental parameters, genetics and biotechnology, harvest and postharvest, fish health management, and others. The synthesized information was used to present the current status of research and development on state fish species. The knowledge gaps that are to be addressed are also depicted under the perspectives of fisheries management and conservation aquaculture. Based on the findings, strategic plans for the targeted conservation programmes are proposed and discussed under various in situ and ex situ conservation measures. Further, the departmental processes involved in the declaration, the importance of stakeholder involvement, namely, local communities and policymakers, in fostering effective conservation measures, and planning for utilization of these valuable fish genetic resources are also indicated.
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Aquicultura , Conservação dos Recursos Naturais , Pesqueiros , Peixes , Animais , Índia , EcossistemaRESUMO
The present study was conducted with the objective of developing ecologically and economically feasible pen culture protocols for Labeo catla as an alternate income source for wetland fishers in the context of the COVID-19 pandemic. Yearlings of L. catla (12.33 ± 1.99 cm mean total length and 26.05 ± 6.57 g mean weight) were reared in HDPE pens (500 m2 area each) at three different stocking densities of 3 (SD3), 6 (SD6) and 9 (SD9) no. m-2 in triplicates. Fishes were fed with floating pelleted feed containing 28% crude protein and 5% crude lipid two times daily at 1.5-3% of body weight. During the culture period, fish grew from 26.05 ± 6.57 to 434.61 ± 30.63 g, 306.13 ± 10.68 g and 221.13 ± 14.92 g, respectively, at stocking densities of 3, 6 and 9 no. m-2 respectively. Weight gain percentage and specific growth rate declined with increase in stocking density. Gross fish yield increased with increase in stocking density and was highest at SD9 (657.92 ± 53.55 kg pen-1), while net fish yield increased initially from SD3 to SD6 (594.31 ± 29.72 kg pen-1) and then declined with further increase in stocking density. Important water quality parameters influencing fish growth were measured, and significant difference (p > 0.05) was not observed between treatments (inside pens) and reference site (outside pen at 10-m distance). Weight gain was positively correlated (p < 0.05) to water temperature (r = 0.989) and total phosphorus (r = 0.81). Benefit cost ratio and net return was highest at SD3 (1.61; US $518.88, respectively). Stocking density of 3 no. m-2 can be considered economically feasible for table fish production of L. catla in pens. Post pen culture, monthly income of fishers increased by 10.76-179.11%, with a mean increase of 90.57%, compared to the period of first COVID-19 wave in India. The present findings can provide an impetus for effective utilization of pen enclosures for income generation and livelihood enhancement of small-scale wetland fishers during pandemic.
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COVID-19 , Carpas , Cyprinidae , Animais , Humanos , Pesqueiros , Ecossistema , Pandemias , Áreas Alagadas , Aumento de PesoRESUMO
Changing climate exerts significant pressure on coastal wetland fishery, ecosystems and livelihood at the eco-regional level. In the present study, an indicator and scoring-based vulnerability assessment framework was developed to assess climate change-induced potential impacts and vulnerability of the coastal wetlands through stakeholder perception and primary data collection on ecology and fisheries. The study was conducted in 12 coastal wetlands in the Gangetic estuarine regions of eastern India. Analysis of rainfall, temperature and extreme climatic events was also carried out. The climate variability in the region was analysed and discussed in the context of ecosystem health and sustainability indicators. The results indicated that anthropogenic stress has a greater influence on ecosystem services than climatic stress. However, the nature and degree of vulnerability of fishers to climate change vary with their capacity to adapt to such changes and alternate sources of livelihood. Altogether, 34 fish species were documented, belonging to 11 taxonomic orders, and categorized as per intensity of resilience using selected criteria. Perception-based climate-resilient adaptation strategies have also been discussed. Developing appropriate adaptation policies and implementing climate-resilient practices and management can minimize vulnerability and increase the adaptive capacity of fishers ensuring sustainable livelihood options.
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Ecossistema , Áreas Alagadas , Animais , Ecologia , Mudança Climática , ÍndiaRESUMO
A new species of the ophichthid eel of the family Ophichthidae is described based on five specimens collected from the Mudasalodai fish landing center, off Cuddalore coast, southeast coast of India, Bay of Bengal. Ophichthus naevius sp. nov. is distinguished from its congeners by having a unique color pattern: dorsal body with numerous dense dark spots or patches, ventral body pale yellowish green, dorsal-fin origin just before pectoral-fin tip, vertebral formula: 12-14/52-53/134-138, and teeth on jaw uniserial and pointed. The study also reports the range extension and molecular evidence of Ophichthus chilkensis from South India. Molecular analyses were performed for both species, and their phylogenetic relationship suggests that the new species exhibits 10.2% genetic divergence with its congener Ophichthus sangjuensis, followed by Ophichthus brevicaudatus (10.4%), and Ophichthus sp. 1 (11.8%) also forms the closest clade in both Bayesian inference and maximum likelihood (ML) tree. Similarly, according to the topology of the ML tree, the species O. chilkensis forms a clade with Ophichthus sp. 5, Ophichthus remiger, Ophichthus frontalis, Ophichthus sp. 6, and Ophichthus rex, suggesting that it would be the genetically closest congener.
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Baías , Enguias , Animais , Enguias/genética , Filogenia , Teorema de Bayes , ÍndiaRESUMO
In vivo study was conducted to determine the role of insulin-like growth factors (IGF-II) related to dietary protein utilization. For this early juvenile stage of marine false clownfish Amphiprion ocellaris, 300 numbers of 20-day-old larvae (initial body weight of 18.2±0.027 mg/fish) were used as an experimental animal. Animals were fed for 12 weeks with different dietary protein levels (35, 40, 45, 50, and 55%), using Spirulina maxima as a major protein source. Proximate compositions and amino acid profile of the formulated diet were analyzed by the standard methods. Eventually, significant (P<0.05) mean, body weight gain, absolute growth rate, specific growth rate, and feed conversion ratio were obtained in the fishes fed with 50% of dietary protein, whereas, poor growth performance was noticed in 35% of the dietary protein level fed juveniles. The growth-responsible gene IGF-II expression studies showed the significant upregulation in the growth of the juveniles at 2.05±0.11 for 40%, 3.13±0.20 for 45%, 4.97±0.13 for 50%, and 4.33± 0.24 for 55%, which were higher than the control group 35%. The study concluded that 50% of dietary protein level is optimal for better growth indices in clownfish; A. ocellaris juveniles and IGF-II can be used as a potential marker gene to assess the growth indices in A. ocellaris.
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Peptídeos Semelhantes à Insulina , Perciformes , Animais , Fator de Crescimento Insulin-Like II , Perciformes/genética , Peixes , Dieta/veterinária , Proteínas Alimentares , Peso Corporal , Ração AnimalRESUMO
In vertebrates, insulin-like growth like factors (IGFs) play an important role in growth and other physiological processes. The GH-IGF axis is considered a valuable tool to monitor fish growth performance. Herein, we report the molecular characterization of igf-1, igf-2, and ß-actin transcripts and relative expression of igf-1 and igf-2 in the liver and muscle tissue of cage-reared butter catfish, Ompok bimaculatus, in response to different stocking densities (T1, 15 fingerlings m-3; T2, 25 fingerlings m-3; and T3, 35 fingerlings m-3) over 180 days of culture duration. The length of the partial amplified transcript sequence of Obigf-1, Obigf-2, and Obß-actin was 325, 438, and 924 bp, respectively. Phylogenetically, Obigf-1 and Obigf-2 were closely clustered with catfishes, viz., Clarias magur, Bagarius yarrelli, and Silurus asotus. The expression of igf-1 was significantly downregulated in the liver at higher densities after 120 days as biomass in the cages increased, while igf-2 expression did not change with the stocking densities over the culture period. Cortisol concentration was significantly elevated in T3 groups post 150 days of the culture period and correlated negatively with the expression of igf-1 (p < 0.05) and igf-2 (p > 0.05). Environmental parameters, pH, TDS, hardness, conductivity, and alkalinity showed a significant positive correlation with hepatic IGF expression. Our study indicates that the liver-derived igf-1 plays a more important role in the regulation of growth in response to culture density in the species studied, and thus, igf-1 can be used effectively as a biomarker for growth. Furthermore, this study will help in planning a proper harvest schedule and optimize the culture practices of O. bimaculatus in an open water cage system.
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Peixes-Gato , Fator de Crescimento Insulin-Like II , Fator de Crescimento Insulin-Like I , Animais , Peixes-Gato/genética , Ecossistema , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like II/genética , Peptídeos Semelhantes à InsulinaRESUMO
The main tributary of the Yamuna, the Tons River, exhibits altitudinal changes in its macroinvertebrate community's diversity, abundance, and composition. Between May 2019 and April 2021, the study was conducted in the upper section of the river. A total of 48 numbers of taxa from 34 families and ten orders were recorded during the investigation. At this elevation of 1150 to 1287 m, the two most predominant orders are Ephemeroptera (32.9%) and Trichoptera (29.5%). During the premonsoon season, they had the lowest macroinvertebrate density (250-290 individuals/m2), and the post-monsoon season had the highest density (600-640 individuals/m2). During the post-monsoon season, the maximum larval forms (60%) of various insect orders were predominant. The findings indicated that lower altitudes (1150-1232 m) have higher macroinvertebrate abundance than higher ones. The diversity of dominance is shallow at site-I (0.0738) and strong at the site-IV during the premonsoon season (0.03837). Taxa richness, as measured by the Margalef index (D), peaked in the spring season (January to March) at 6.9 and reached its lowest point (5.74) in the premonsoon season (April to May). Only 16 taxa were discovered in site-I and site-II, but 39 taxa were discovered at low altitudes (site-IV, 1100 m) (1277-1287 m). The Tons River contains a total of 12 and 13 genera, respectively, that belong to the orders Ephemeroptera and Trichoptera, according to qualitative study of the macroinvertebrates. The current study supports the use of macroinvertebrates as bioindicator species for monitoring biodiversity and assessing the health of ecosystems.
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Ecossistema , Ephemeroptera , Humanos , Animais , Rios , Estações do Ano , Monitoramento Ambiental , ÍndiaRESUMO
A new species of the genus Macrocephenchelys is described herein based on a single specimen collected from the deep-sea trawl landing at Kalamukku fish landing centre, Kerala coast, Arabian Sea. The new species is distinguished by having a dorsal-fin origin behind the middle of pectoral fin, a larger head, shorter trunk, larger gill opening, dorsal surface of body with dark-brown colour and ventral surface of head and belly with numerous patches of melanophores before anus, vertebrae 14-30-151. The new species shares most of the characteristics with Macrocephenchelys brevirostris but differs from it by having a more anterior dorsal-fin origin (vs. over the tip or slightly behind the pectoral-fin tip), larger head [15.3% total length (TL) vs. 10.5%-13.9% TL, 53.2% pre-anal length (PAL) vs. 35.8%-47.6% PAL], shorter trunk length (13.6% TL vs. 14.4%-20.6% TL, 47.3% PAL vs. 52.4%-66.2% PAL); further it shows 7.9%-8.1% genetic divergence from the sequences of M. brevirostris.
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Enguias , Peixes , Animais , Brânquias , Coluna Vertebral , MelanóforosRESUMO
Tropical inland capture fisheries are susceptible to a series of vulnerabilities such as habitat destruction, biodiversity loss, pollution, overfishing, invasive species and anthropogenic climate change. A comprehensive review of the impact of climatic uncertainties on Indian inland fisheries has not been adequately attempted yet. Recent approaches emphasizing ecosystem-based management in a regional context, specific to inland fisheries for combating climatic changes, have not been reported to date. The paper presents a critical bibliometric review of the climatic vulnerabilities faced by Indian inland fishery resources and various adaptive and mitigation strategies put forward by the country for the sustainability of the resources. In this communication, a systematic review of the impact of climate change and other stressors on various inland ecosystems of the subcontinent and the ecosystem-based management strategies adopted in India is presented and discussed.
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Ecossistema , Pesqueiros , Mudança Climática , Conservação dos Recursos Naturais , BiodiversidadeRESUMO
The present study aims to understand the spatio-temporal dynamics in habitat ecology and fish assemblage and determine the relationship of habitat transition and fish distribution in a large riverine-reservoir cascade system (Sardar Sarovar Reservoir part in Madhya Pradesh). This study was carried out along a 125-km riverine-reservoir interface (RRI) during 2018-2020. The study showed presence of a total of 110 fish species (104 spp. in upstream main Narmada River stretch excluding reservoirs, 56 in RRI, and 39 in Sardar Sarovar reservoir). We recorded 50 species common in upstream riverine stretch of Narmada and the RRI while RRI uniquely harbored 3 native species (Chitala chitala, Labeo boga, Salmostoma phulo) not previously reported from Narmada River stretch upstream. The similarity percentage (SIMPER) analysis showed presence of S. phulo causing 27.91%, Schistura dayi (3.71%), and Rita pavimentata (3.41%) of dissimilarity among Maheshwar (S1), Rajghat (S2), Koteshwar (S3) non-confluence zone, and Kakrana (S4)-confluence zone. The analysis of data indicated disappearance of some species like deccan peninsular carp Labeo fimbriatus, Mahseer Tor khudree which was earlier reported but was absent in recent years. The statistical correlation of environmental variables with observed abundances of fish feeding guilds showed significant positive correlation with specific conductivity and total dissolved solid content of the water. The canonical correspondence analysis (CCA) indicated association among omnivorous fishes of the reservoir with water temperature; total dissolved solids; specific conductivity; total alkalinity; chlorophyll; and NO3-N. The herbivore fishes were found to be more associated with magnesium, dissolved oxygen, and phosphorus content of the water while insectivorous fishes were more associated with the silicate and transparency of the water. The abundance of omnivores species indicated dominance of generalist fish species rather than specialists in the interface region of reservoir showing conservation and ecological importance of the ecosystem. The baseline information generated on fish assemblage and ecological perspectives of the river reservoir interface and science-based management recommendations formulated in the study are critical for sustaining fish diversity, promoting fisheries enhancement, and management planning of tropical large reservoirs.
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Ecossistema , Rios , Animais , Rios/química , Qualidade da Água , Peixes , ClorofilaRESUMO
Construction of a physical chromosome map of a species is important for positional cloning, targeted marker development, fine mapping of genes, selection of candidate genes for molecular breeding, as well as understanding the genome organization. The genomic libraries in the form of bacterial artificial chromosome (BAC) clones are also a very useful resource for physical mapping and identification and isolation of full-length genes and the related cis acting elements. Some BAC-FISH based studies reported in the past were gene based physical chromosome maps of Clarias magur (magur) to understand the genome organization of the species and to establish the relationships with other species in respect to genes' organization and evolution in the past. In the present study, we generated end sequences of the BAC clones and analyzed those end sequences within the scaffolds of the draft genome of magur to identify and map the genes bioinformatically for each clone. A total of 36 clones mostly possessing genes were identified and used in probe construction and their subsequent hybridization on the metaphase chromosomes of magur. This study successfully mapped all 36 specific clones on 16 chromosome pairs, out of 25 pairs of magur chromosomes. These clones are now recognized as chromosome-specific makers, which are an aid in individual chromosome identification and fine assembly of the genome sequence, and will ultimately help in developing anchored genes' map on the chromosomes of C. magur for understanding their organization, inheritance of important fishery traits and evolution of magur with respect to channel catfish, zebrafish and other species.
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Peixes-Gato , Animais , Peixes-Gato/genética , Cromossomos Artificiais Bacterianos/genética , Peixe-Zebra/genética , Cromossomos/genética , Clonagem Molecular , Mapeamento Físico do Cromossomo/métodosRESUMO
Wetlands provide a great ecological service by accumulating and sequestering carbon in their soils and thus help in mitigating climate change caused due to global warming. However, the capacity and efficiency of different types of wetlands vary considerably depending upon the nature of the wetland, hydrology, biogeochemistry, climatic condition, and many other factors. In the present paper, we have studied the carbon accumulation and sequestration in three different wetlands, one sewage fed, and two floodplain oxbow lakes in the West Bengal state of India. The selected wetlands vary in terms of ecological regimes such as water volume, depth, link channel, agricultural runoffs, primary productivity, macrophyte coverage, and fishery. The carbon accumulation in the wetlands, which varied from 48.53 to 143.17 Mg/ha up to 30-cm depth of soil, was much higher than that in the corresponding upland sites. The difference was much higher in the floodplain wetlands. So the study revealed that wetlands are better carbon sinks than the corresponding reference sites and the carbon sequestration potential varies according to the type of wetlands. A positive correlation was also observed between macrophyte coverage and the amount of C stored in the wetlands.
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Sequestro de Carbono , Áreas Alagadas , Monitoramento Ambiental , Solo , Carbono/análiseRESUMO
The rapid degradation, overexploitation, and encroachment of floodplain wetlands have led to considerable decline in fish diversity and production from these invaluable aquatic resources threatening livelihood of the dependent fishers. The climate change evident in the fast few decades has further aggravated the problem of eutrophication causing water stress and sedimentation leading to rampant macrophyte proliferation affecting ecological and economic functioning of these ecosystems. Macrophyte control and management needs serious attention for sustaining ecosystem services provided by these resources. In this direction, pen culture of grass carp Ctenopharyngodon idella as a biocontrol for macrophytes along with Indian major carps was implemented in a co-management mode in Beledanga, a typical floodplain wetland, a gradually shrinking, macrophyte dominated floodplain wetland in lower Ganga basin. Indian major carps Labeo catla (6.28±0.23g), Labeo rohita (5.1±0.12g), Cirrhinus mrigala (3.5±0.08g) were stocked in the ratio 4:3:3 at the rate of 20 Nos.m-2 in pens (0.1ha each) in triplicate. Grass carp (7.1±0.42g) was stocked in pen at the rate of 20Nos.m-2 in duplicate. The fishes were fed with pelleted feed twice a day at the rate of 2-3% of body weight. The seed was overwintered in pens for a period of 90 days from November 2019 to January 2020. Average weight recorded at the end of culture period was 25.13±1.70g, 18.11±0.63g, 14.53±0.87g, and 39.20±1.90g in L. catla, L. rohita, C. mrigala, and C. idella, respectively. The survival of fish ranged from 70 to 81%. Growth performance and feed utilization efficiency of grass carp were significantly higher (p<0.05) compared to other carp species. The pen culture was found to be economically viable with a benefit cost ratio of 1.53. The fishes produced were released back into the open wetland as an additional input for culture-based fisheries. The intervention along with niche-based enhanced stocking led to 24% increase in the fish production from the wetland with grass carp contributing 20-22% of the total catch with 32% increase in revenue generated by the sale of fish within a short span of 1 year. The study successfully demonstrated technological suitability and economic feasibility of pen culture in this wetland and role of grass carp as a potential biocontrol species for macrophyte management. Grass carp stocked in open wetland grew to 0.8 to 1kg within 6 months and 2-2.3kg within a year and could utilize 40-45% of the submerged and emergent macrophytes. Integration and optimization of grass carp will not only aid in habitat management of macrophyte-choked wetlands but will also boost their small-scale fisheries by converting standing macrophyte biomass into protein-rich fish biomass. The enhanced production will also cater to nutritional and livelihood security of the dependent fishers.
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Carpas , Pesqueiros , Animais , Aquicultura , Ecossistema , Áreas AlagadasRESUMO
The present study was conducted for 240 days to evaluate the effects of stocking density based on growth attributes, digestive enzymes, muscular composition, biochemical and physiological responses of Labeo rohita fingerlings in tropical inland open water cages. L. rohita (30.35 ± 1.08 g) were randomly distributed into three treatments, namely low stocking density, LSD (10 m-3), medium stocking density, MSD (20 m-3) and high stocking density, HSD (30 m-3) in triplicates. Fish were fed twice daily with CIFRI CAGEGROW® floating feed (crude protein-28%, crude fat-4%). Fish growth and feed efficiency were higher (p < 0.05) in LSD, however, MSD registered a higher yield. Amylase and protease activity reduced whereas lipase activity increased with increasing stocking density. Muscle crude protein and crude fat formed an inverse correlation. The fillet quality deteriorated at higher stocking densities based on Muscle pH, drip loss and frozen leakage rate. The stress biomarkers level (glucose, cortisol, superoxide dismutase and catalase) increased in serum under crowding conditions. Glutamate oxaloacetate transaminase and glutamate pyruvate transaminase in serum were significantly increased in HSD. Serum protein levels decreased with the increase in stocking densities. Body ionic imbalance (Na+, Cl- and K+) was observed under crowding stress. Based on growth attributes and multiple biomarker responses, L. rohita @ 10 m-3 was found to be the optimum density for inland open water cage culture.
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Cyprinidae , Animais , Biomarcadores , Glutamatos , Transaminases , ÁguaRESUMO
Wetland fisheries are most vulnerable to climate and anthropogenic change, and therefore, vulnerability assessment is essential for the formulation of prudent management strategies. In the present study, vulnerability assessment was carried out in nine floodplain wetlands from three districts of West Bengal using stakeholder perception and ecological conditions. In absence of long-term time series data on ecology and fisheries of wetlands, stakeholder perception study was carried out to assess the vulnerability status to climate change. Phased interviews were conducted using structured questionnaires to study the stakeholder perception on climatic variability and changes in ecology and fisheries of wetlands over the past 15 years. Climate data used for climate trend analysis was procured from Indian Meteorological Department. Ecological parameters were studied from the wetlands seasonally from January 2018 to December 2018. Analysis of climatic variables for last three decades revealed a warming trend and decreasing rainfall in the study area. The temperature anomaly ranged from + 0.07 to + 0.31 °C while rainfall anomaly ranged from - 61.41 to - 372.62 mm. Respondents showed high level of consensus (75.3%) on climate change awareness. The respondents were aware of the fact that climate anomaly affects ecology and fisheries of wetlands in most of the cases with consensus ranging from 67.8 to 94.7%. The studied wetlands showed 2 to 81.28% reduction in depth, 21.52-61.29% reduction in species diversity, and 30-95% macrophyte infestation. The stakeholder perception-based vulnerability scores ranged from 18 to 31 and indicated 6 out of 9 wetlands (66.6%) as highly vulnerable and the rest as moderately vulnerable. The ecological vulnerability scores ranged from 17 to 21 and indicated 5 out of 9 wetlands (55.6%) as highly vulnerable and 4 wetlands in the moderately vulnerable range. Although both the approaches used in the present study categorized the studied wetlands as moderately to highly vulnerable, the category of some of the wetlands varied in both the approaches. This suggests that utilizing a single approach may not give precise vulnerability status of an ecosystem. Use of combined approaches for construction of a composite vulnerability index covering different aspects impacted by climate change might present a better picture of the vulnerability status and aid in formulation of effective mitigation/management plan.
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Ecossistema , Áreas Alagadas , Mudança Climática , Percepção , TemperaturaRESUMO
India has different bioclimatic zones and supports diverse aquatic habitats rich in biodiversity. For effective conservation of the endangered species in its habitat, it is essential to know the distribution of fish species in the environmental range, and for this, species distribution models are the efficient and innovative tools. The present study used the MaxEnt modeling technique for developing probability distribution models highlighting the distribution of fish species by analyzing the known occurrence records of Denison barb under genus Sahyadria (Sahyadria denisonii Day 1865 and Sahyadria chalakkudiensis (Menon et al., Rec Zool Surv India 97:61-63, 1999)) in relation to environmental variables typically incorporating seasonal and temporal variability. AUC of the models for Sahyadria species depicted good fitness. Both species were found sensitive to "solar radiation," "temperature seasonality," and "temperature annual range" and assessed as significant predictors. The sensitivity and distribution of both species to these environmental variables were found correlated with their breading and spawning seasons. "Precipitation" was determined as one of the significant climatic envelopes influencing the distribution of the species associated with river flow. The models showed the distribution of S. denisonii in the higher precipitation areas compared to S. chalakkudiensis. The probability distribution model with respect to the distribution of both species indicates a lineage barrier at Palghat Gap supporting the earlier studies. At the latitudinal scale, prediction of the suitable ecological habitat provides a detailed insight into the distribution of all genetic lineages of the genus Sahyadria. Evidently, the findings of this study can assist in determining ecological niches for endangered species of other areas and may aid in field surveys as well as developing conservation plans.
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Cyprinidae , Ecossistema , Animais , Biodiversidade , Espécies em Perigo de Extinção , Água DoceRESUMO
OBJECTIVES: We aimed to evaluate blood pressure (BP) in Indian children who had similar demographic characteristics but hailed from different altitudes. METHODS: BP of school going children, aged 5 to 12 years, at five different locations varying in altitude (near sea level: n = 425; 2000 feet: n = 244; 4000 feet: n = 248; 6000 feet: n = 242 and 8000 feet: n = 250) was measured in a mountainous district in Himalaya. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were recorded by aneroid sphygmomanometer in the sitting posture using a calibrated instrument and four trained resident doctors. The average of three readings was taken. RESULTS: Of the 1229 children whose data were analyzed, 50.4% were boys. SBP showed a progressive rise from 99.5 (4.00) mmHg [mean (standard deviation)] at near sea level to 106.7 (4.17) mmHg at 8000 feet. Similarly, DBP showed a rise from 60.1 (3.67) mmHg to 66.8 (4.58) mmHg over the same altitude range. Analysis of covariance for BP variation with altitude, with age as covariate, indicated a modest but statistically significant rise in both SBP and DBP with altitude. Higher BP values was noted among children residing at higher than at lower altitude (0.8% at sea level to 18.8% at 8000 feet). Correlations between SBP and DBP values and height and weight, though positive and significant at p < 0.01 level, were weak. CONCLUSIONS: These data will help in correct interpretation of BP readings in children residing at high altitude.
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Altitude , Hipertensão , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial , Estatura , Criança , Pré-Escolar , Humanos , MasculinoRESUMO
The geographic information systems (GIS) play an important role in all geospatial aspects of assessment, monitoring, and management of inland open water resources for strategic development in the fisheries sector. In India, reservoir fisheries development is one of the flagship programme and several initiatives have been taken up towards enhancement and sustainable development. The present study investigates spatio-temporal changes in ecology and fisheries in Hirakud reservoir, Odisha, build across river Mahanadi which features one of the largest dams in South Asia during 2016-17 to 2018-19. The reservoir is mainly utilized for electricity generation, irrigation and offers tremendous scope to support fisheries and livelihood. The mean water spread area during 2016-17 to 2018-19 was at the minimum (42721 ha) during premonsoon period and was at the maximum (62059 ha) during monsoon. Most of the water quality parameters including nitrate, BOD, and alkalinity during 2016-17 to 2018-19 were higher in the premonsoon period and overall, the parameters were under favorable range for fisheries. The present investigation from the fish landing sites of the reservoir, recorded merely 40 fish species, indicating loss of fish diversity as compared to the historical reports. The IUCN conservation status showed that among the 40 species only one species, Wallago attu is under the VU category and 4 species Chitala chitala, Ompok bimaculatus, Ailia colia, and Bagarius bagarius are under the NT category. The fish production in the reservoir was 8200 t during 2018-19. The analysis of time series annual fish catch data using the ARIMA model forecasted the increasing trend of fish production. The water quality parameters were presented in the GIS platform for a better understanding of the spatial variations over time. Habitat protection of fish breeding grounds, closed seasons, mesh size regulations, scientific management, and community participation are recommended as the measures for conservation of fish diversity and sustainable enhancement of fish production in the reservoir.
Assuntos
Peixes-Gato , Pesqueiros , Animais , Conservação dos Recursos Naturais , Ecologia , Ecossistema , Peixes , Desenvolvimento SustentávelRESUMO
The present study assessed the occurrence and impact of heat waves on the ecology of two ecosystems namely Bhomra wetland and Ganga River stretch, India. The water samples collected from these ecosystems were analyzed for estimating the hydrological and biological variables during heat wave. The inland heat index (IHI) was derived from the climatic variables, relative humidity and temperature. The study indicated the predominant and periodic occurrence of inland heat waves (IHW) with indices ranging from 34.8 to 42.8 °C and 35.9 to 43.5 °C at the Bhomra and Ganga River stretch respectively during the summer months (March-June). The first two components of the principal component analysis of physico-chemical parameters and heat index explained 45.6% and 59% of the variation in the Bhomra and Ganga River stretch respectively. PCA showed a similar pattern in variation of IHWs and dissolved oxygen, nutrients, hardness and alkalinity, but a distinct pattern with conductivity and TDS in the wetland. IHW exhibited a similar pattern of variation with TDS, conductivity, dissolved oxygen, pH and hardness and distinct pattern with alkalinity, phosphate and nitrate in the river stretch. The first two components of PCA of IHI and plankton abundance explained 89% of the variation and IHI had a similar pattern of variation with the abundance of diatoms and a diverse pattern of variation with blue-green and green algae in the studied ecosystems which might affect the food availability of the associated fishes. The study suggests that IHW influences the water quality and primary producers and also summarizes the impact of IHW on ecosystem services and necessitates mitigation measures.