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1.
B. B. Jana 《Hydrobiologia》1978,61(2):135-143
Estimates of planktonic growth kinetics in relation to the thermal environment were made over a two year period in three hot springs and one cold one located in West Bengal, India. A very characteristic feature of the Saubhagya Kund (43–49°C) and Papahara (46–51°C) was the abundance of phytoplankton, always dominated by blue-green algae. This situation changed in the other two springs where zooplankton was an essential component. The determination of the species diversity index indicated that the graph of cumulative species of plankton versus logarithm of individuals was roughly linear in Saubhagya Kund and Papahara, whereas in the other two a logistic curve was the result. The seasonal distribution of Myxophyceae/Phytoplankton was dependant upon the annual phosphorous cycle (P < 0.0001) in all the thermal waters studied. That the population dynamics of diatoms responded inversely to the level of phosphate (P < 0.05) has been clearly manifested in Swetganga (37–46°C). The variation in the silicate content of the water throughout the year has been found responsible for the seasonal succession of diatoms in some of the waters (P < 0.001). The multiple correlation between phosphate, silicate, dissolved oxygen and pH and Myxophyceae/Phytoplankton was significant in the case of Papahara (P < 0.01) and Swetganga (P < 0.05). Similarly, the multiple correlation between these factors and Bacillariophyceae was significant in Saubhagya Kund (P < 0.01). In the non-thermal water Jibatsa Kund (22–39°C), the multiple correlation between these factors and Phytoplankton was, however, not significant (P > 0.05). 相似文献
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Reservoirs are artificial water bodies having social application and hybrid characters of both river and lake. Thorough analysis of water quantity and quality is necessary to ensure the health of these ecosystems, as they are considered one of the major water sources in developing countries. Biological subsystem of reservoirs consists of both autotrophs and heterotrophs in the open zone and littoral zone. These components are critical for freshwater aquatic food webs. Bakreswar reservoir has been selected as the current study site. Static model representing ecosystem trophic structure is developed through Ecopath with Ecosim software and is analysed to obtain idea about the ecosystem functioning and functioning. This reservoir is found to be approaching maturity but with vulnerabilities being present as is evident from the studies of ecosystem attributes, transfer efficiencies, mixed trophic impact, niche overlap and other attributes. Good assemblage of biota like macrophytes, zooplankton etc. is observed, thus presenting some diversity in the food web. Based on the primary production to respiration ratio, this system can be categorized as a moderately mature and healthy ecosystem but is vulnerable to perturbations as is evident by low values of connectance index and system omnivory index. Comparatively low Finn cycling index indicates that this system is approaching maturity but is vulnerable. With a pedigree index of 0.459, the model is well suited for the study site. The knowledge thus obtained for this reservoir can be utilized to form proper management strategies to facilitate successful conservation management and proper resource utilization. 相似文献
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Sandra Bessudo Felipe Ladino Edgar Eduardo Becerril-García Charles M. Shepard Pelayo Salinas-De-León Edgar Mauricio Hoyos-Padilla 《Journal of fish biology》2021,99(5):1769-1774
Management and conservation actions in marine-protected areas require baselines for monitoring threatened marine fauna such as elasmobranchs. This article provides evidence of the occurrence of 34 species of elasmobranchs (21 sharks and 13 batoids) in the Malpelo Flora and Fauna Sanctuary, Colombia, including five new records of sharks and three of rays. From 1987 to 2021, new records were obtained by underwater visual census using SCUBA, manned submersibles and deep-ocean cameras to depths of up to 2211 m. Of the recorded species, 21 are considered as threatened taxa (64%) by the IUCN, making the Malpelo Flora and Fauna Sanctuary an essential conservation area for this highly threatened group of species. 相似文献
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The influence of environmental parameters on the bacterial populations of thermal springs in West Bengal, India 总被引:2,自引:0,他引:2
The physico-chemical characteristics and the bacterial populations of three thermal springs in West Bengal have been examined. The springs range in temperature from 42o C (Saubhagya Kund) to 65o C (Agni Kur.d). The levels of carbonate and bicarbonate alkalinity, total hardness and the ppm of chloride, phosphate and silicate as well of dissolved oxygen were measured at monthly intervals. Estimates of the bacterial populations were obtained from cultures. Water samples incubated at 37o C for enumeration of mesophilic microbes, at 50o C for thermo-tolerant bacteria and at 60o for strict thermophiles. Tests for coliform organisms were carried out at 37o C and at 50o C.
All three springs show seasonal variation in their physico-chemical characteristics and in their bacterial populations. The cooler springs have large populations of mesophilic and thermotolerant bacteria but fewer thermophilic types. In the two hot springs (Saubhagya Kund and Swetganga), the differences of mean bacterial populations observed between 37o and 50"C and between 50o and 60o C are highly significant ( P < 0.01), in the third (Agni Kund) the differences are also significant ( P < 0.01) but the population showed a rising trend with the temperature. Of the biotic and abiotic factors which could be involved in the observed seasonal variation in the bacterial populations, only the fluctuations in the phosphate levels were found to show a significant correlation (0.001 < P < 0.01). 相似文献
All three springs show seasonal variation in their physico-chemical characteristics and in their bacterial populations. The cooler springs have large populations of mesophilic and thermotolerant bacteria but fewer thermophilic types. In the two hot springs (Saubhagya Kund and Swetganga), the differences of mean bacterial populations observed between 37
5.
Abandoned limestone quarries are hostile environments for plant and invertebrate colonization and establishment. The length of time taken for successful establishment by natural processes may be unacceptable for reclamation purposes; several techniques are used to reduce the time scales involved. A new technique, restoration blasting, aims to replicate natural daleside landforms by selective blasting of modern production quarry faces. We compare the flora and invertebrate fauna of restoration-blasted sites, hydro-seeded with daleside species, with naturally regenerating disused quarries and a natural daleside. Restoration-blasted sites were found to have less plant cover, more bare ground, fewer orders of invertebrates, and generally fewer animals within each order than the other two types of site. The disused quarries tended to have intermediate characteristics between the restoration-blasted sites and the natural daleside. The age of the site may be important in determining the plants and invertebrates occurring there. This may be related to the time available for establishment or a greater degree of settlement or stability within the biotic and abiotic components of the site. Although most of the results indicate that time since establishment may be important, some variations occur. In particular, the development of vegetation cover in areas grazed by rabbits is problematic. These results are important in the assessment of successful reclamation because the invertebrate fauna may contribute greatly to the overall system. Both plant and animal communities appear to be establishing well on the sites reclaimed by restoration blasting. Further monitoring will identify the speed at which such environments achieve the desired aim of replicating daleside communities and the communities best able to be sustained following this technique. 相似文献
6.
This paper describes an analysis of the plants of Sambalpur district of Orissa, India which have been used medicinally by local people. The families having medicinal values are analysed using Moerman's method of regression analysis. There were 136 plant families recorded from the study area. The analysis of families showed that the Euphorbiaceae family being used most ethnomedicinally by the local people in Sambalpur district of Orissa, whereas Poaceae is used least one. This type of study determines the degree of importance of plant families in the medicinal flora of the region. 相似文献
7.
《植物分类与资源学报》2010,(6)
This paper describes an analysis of the plants of Sambalpur district of Orissa,India which have been used medicinally by local people. The families having medicinal values are analysed using Moerman's method of regression analysis. There were 136 plant families recorded from the study area. The analysis of families showed that the Euphorbiaceae family being used most ethnomedicinally by the local people in Sambalpur district of Orissa,whereas Poaceae is used least one. This type of study determines the degree of importance of plant families in the medicinal flora of the region. 相似文献
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In order to extend quarrying near Thrislington Plantation, County Durham, England, 8.5 ha of magnesian limestone grassland was relocated over a period of eight years from October 1982. The effects of this on the flora and invertebrate fauna were examined within the Festuca-Helianthemum community at five plots relocated at different times. Plants were sampled with a point-quadrat, and invertebrates by pitfall trapping. Comparisons were made between age of the relocation, numbers of species and individuals, and diversity of flora and invertebrates. The plots were examined using the percentage similarity measure. The plots showed an initial change in some aspects of community structure for flora and invertebrate fauna, followed by a “recovery” period. This was particularly evident in the numbers of species and species diversity of plants and in the numbers of individuals and species diversity of invertebrates. Bare ground, left by the relocation process, was still evident between relocated turfs in the early plots, but it was successfully colonized by resident species in later plots. These results have implications for the future management of this and similar sites, particularly with respect to the emphasis placed on subsequent monitoring and the need to consider invertebrate faunas when implementing management strategies. 相似文献
10.
B. Verdcourt 《Kew Bulletin》2009,64(1):183-194
Material from the Malaise trap operated by D. Baldock in 2002 continues to be identified and records of beetles omitted in
previous supplements are listed here. Other casual records from various sources are also given. Tom Cope has continued his
studies on the Wild Flora of the Gardens. Diego Fontaneto and Tim Barraclough collected rotifers in the gardens in November
2004. Members of the British Arachnological Society visited Kew on 10th September 2004 and a complete list of spiders and
harvestmen found in the gardens is attempted. 相似文献
11.
Avifauna of Khajjiar lake revealed the presence of 77 species of birds belonging to 62 genera, 12 orders and 31 families. In this area Muscicapidae is the most represented family with 22 species belonging to 15 genera followed by Accipitridae and Corvidae (six species each), Paridae, Phasianidae, Columbidae and Picidae (three species each). 20 species of birds were local and the rest 57 seasonal-local and long range migrants Of the 57 species, 35 were seasonal-local migrants, four were winter visitors and ten were summer visitors. Moreover, Khajjiar lake supported eight such species which showed winter and summer influx. Of these, six showed summer influx, whereas, winter influx was shown by two species only. Data on relative abundance showed that 25 species of birds were very common, 30 common, 21 uncommon and one rarely seen in the area. 相似文献
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Mehdi Fazlzadeh Roohollah Rostami Abbas Norouzian Baghani Adel Mokammel 《人类与生态风险评估》2018,24(6):1441-1452
This study aimed to assess hydrogen sulfide (H2S) concentrations in the pool indoor air of hot springs and its link to some physicochemical properties of the springs in Ardabil province. Twenty-two hot springs from different regions were selected and monitored for H2S concentrations using a portable gas meter. Respective mean concentrations of H2S in hot springs indoor air were 9.11 ± 11. Ghotour Souei hot springs had the highest concentration of H2S with a mean concentration of 29.4 ± 7.7 and 25.2 ± 8.16 ppm at the source and general pool areas, respectively. Oxidation-reduction potential and pH of the water were the most important factor influencing H2S concentrations in the hot springs. H2S concentrations in indoor air of Ardabil hot springs were noticeably higher than OEL-TWA and OEL-STEL, and therefore may pose important risks for human health on both short-and long-term exposures. 相似文献
14.
Malpelo Island is the largest marine protected area (MPA) in the Colombian Pacific; however, the lack of information regarding its ecological dynamics suggests that management and conservation strategies are developed from an individual approach (species or groups of species) and not from an ecosystem one. This study analyzes the terrestrial food web of Malpelo Island, Colombia, based on topological analysis (e.g., centrality). The food web was constructed from 27 nodes representing the main trophogroups, which consist of species or functional groups. Malpelo Island had a food web of four steps with a maximum separation among all trophogroups and trophic pathways, with two steps in average length. Furthermore, the food web was divided into three food web compartments, with a recurrence of connectivity patterns dominated by apparent and exploitative competition, followed by tri-trophic chains and omnivory. Five key trophogroups control the energy flow throughout the food web (detritus, the land crab Johngarthia malpilensis, the lizard Anolis agassizi, the Malpelo dotted galliwasp Diploglossus millepunctatus, and the Nazca booby Sula granti). The high importance of detritus suggests that bottom-up processes act as a control and regulation mechanism of trophic flows. The low number of food web compartments and a high recurrence of specific connectivity patterns in the Malpelo Island terrestrial ecosystem evidence different ecological processes centered on five trophogroups, allowing stability against disturbances. In addition, the simulation of trophogroup removal (randomly or directed) suggests that food web can be vulnerable to structural alterations in their properties, which may have consequences on the resilience of this ecosystem. This study contributes to the knowledge of the trophic dynamics of Malpelo Island, providing a potential tool for management and conservation measures from an ecosystemic approach. 相似文献
15.
Biodiversity of the insect fauna of natural mangrove ecosystem (Pitchavaram) and adjusted mangroves (Parangipettai), was studied through weekly sampling programmes from April 2013 to September 2013. A total of 27 species belonging to 17 families (Formicidae, Sphecidae, Curculionidae, Scolytidae, Tenebrionidae, Culicidae, Nymphalidae, Crambidae, Pyralidae, Tortricidae, Lecidotheridae, Pieridae, Pyrrhocoridae, Corixidae, Apidae, Gerridae and Diaspidiae) were recorded. This work is the checklist of the collected insect fauna from the Pitchavaram and Parangipettai mangrove areas lying along the Southeast coast of India. 相似文献
16.
Rath CC 《Cytobios》1999,99(391):105-111
Thermotolerant bacteria (35 in toto) isolated from three hot springs (Atri, Taptapani and Deuljhari, Orissa), were screened for lipase activities. Of these, nine strains of Bacillus spp. and three strains of Pseudomonas spp. showed heat stable lipase activity at 60 degrees C. The hydrolytic activity of these bacteria was tested using Tween-20 and Tween-80 as substrates at different temperatures using plate assay and titration techniques. The hydrolytic activity at different pH values and salt concentrations was investigated. 相似文献
17.
India is one of the 12 mega biodiversity countries of the world, which represents 11% of world''s flora in about 2.4% of global land mass. Approximately 28% of the total Indian flora and 33% of angiosperms occurring in India are endemic. Higher human population density in biodiversity hotspots in India puts undue pressure on these sensitive eco-regions. In the present study, we predict the future distribution of 637 endemic plant species from three biodiversity hotspots in India; Himalaya, Western Ghats, Indo-Burma, based on A1B scenario for year 2050 and 2080. We develop individual variable based models as well as mixed models in MaxEnt by combining ten least co-related bioclimatic variables, two disturbance variables and one physiography variable as predictor variables. The projected changes suggest that the endemic flora will be adversely impacted, even under such a moderate climate scenario. The future distribution is predicted to shift in northern and north-eastern direction in Himalaya and Indo-Burma, while in southern and south-western direction in Western Ghats, due to cooler climatic conditions in these regions. In the future distribution of endemic plants, we observe a significant shift and reduction in the distribution range compared to the present distribution. The model predicts a 23.99% range reduction and a 7.70% range expansion in future distribution by 2050, while a 41.34% range reduction and a 24.10% range expansion by 2080. Integration of disturbance and physiography variables along with bioclimatic variables in the models improved the prediction accuracy. Mixed models provide most accurate results for most of the combinations of climatic and non-climatic variables as compared to individual variable based models. We conclude that a) regions with cooler climates and higher moisture availability could serve as refugia for endemic plants in future climatic conditions; b) mixed models provide more accurate results, compared to single variable based models. 相似文献
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T. S. Zelenkina B. Ts. Eshinimayev O. P. Dagurova N. E. Suzina B. B. Namsarayev Yu. A. Trotsenko 《Microbiology》2009,78(4):492-497
The number, activity, and diversity of aerobic methanotrophic bacteria in the sediments of three coastal thermal springs of Lake Baikal were analyzed. The average number of methanotrophs was 103–104 cells per 1 cm3 of sediment. The highest number of methanotrophs (108 cells/cm3 of silt) and the highest potential rate of methane uptake [7.7 nmol CH4/(cm3 day)] were revealed in sediments from the Sukhaya thermal spring. The methods of molecular ecology (DGGE, FISH, analysis of pmoA gene fragments) showed the predominance in most enrichment cultures of methanotrophs of type II, i.e., of the genera Methylocystis and Methylosinus. In only one enrichment culture (from the Sukhaya thermal spring), a type I methanotroph was revealed; its similarity to Methylococcus capsulatus Bath did not exceed 80%. These results demonstrate a widespread occurrence and high activity of the aerobic methanotrophic community in the coastal thermal springs of Lake Baikal. 相似文献