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1.
Artisanal fishing is an activity which has long occupied an important place on the West African coast. In less than 20 years,
the increasingly widespread use of motors in fishing boats and cold storage facilities both on board and on land have enabled
fishermen to master the constraints of space and time. Furthermore, globalization has created a demand for new products, thus
influencing the behaviour of fishermen and consequently the status of some fish, turtle and marine mammal species. Development
policies for artisanal fishing do not adequately reflect the importance of these changes. They tend to use inappropriate scales
of reference, be it spatially (national borders take precedence over ecosystems) or temporally (the long-term consequences
of development plans are seldom considered). Some international conservation organizations are testing promising new approaches
to managing resources more sustainably and restoring degraded ecosystems, and their recent experiences can serve as useful
examples to others. It is recommended to grant special rights of access to resident fishermen. In defending ‘their’ resources,
they will also protect the ecological functions of the area. Close collaboration with administrations and development assistance
agencies is needed to assess consequences of political decisions on the use of resources. The important role of marine protected
areas as a tool for fishing management should be better documented and strengthened. These areas should not be considered
as isolated units but rather as vital parts of a comprehensive system for improved coastal zone management. Consistent with
the ecosystem approach, fishermen and their communities, being the main users of coastal resources, should also play a major
role in the design and implementation of any fishing management actions. 相似文献
2.
Mondal D Barat S Mukhopadhyay MK 《Journal of environmental biology / Academy of Environmental Biology, India》2007,28(1):119-122
Static renewal bioassay tests were conducted to evaluate the acute toxicity of two neem based biopesticides, applied widely on tea plantation namely, Nimbecidine and Neem Gold either separately as well as, in combination to the fingerlings (mean body length- 4.46 +/- 0.15 cm; mean body weight- 0.49 +/- 0.15g) of a fresh water loach, Lepidocephalichthys guntea (Hamilton Buchanan) acclimatized to laboratory conditions prior to experiment. The 96 hours LC50 values for Nimbecidine and Neem Gold and the combination of the two were 0.0135 mgl(-1), 0.0525mgl(-1) and 0.0396 mgl(-1), respectively. The regular water quality analysis showed, that with increasing doses of biopesticides, dissolved oxygen level was lower and other parameters like pH, free carbon dioxide, total alkalinity total hardness, chloride ions of water increased. The fish under toxicity stress suffered several abnormalities such as erratic and rapid movement, body imbalance and surface floating responding proportionately to the increase in concentrations of the toxicant biopesticides. The 96 hours LC50 values proved Nimbecidine more toxic than Neem Gold and the combination of the two biopesticides. 相似文献
3.
In most protected areas of the Indian Himalayan region site/habitat characteristics, community diversity and distribution pattern, vegetation composition (richness of native and endemic species), structural patterns, economic importance of forest communities and community priorities have rarely been studied. Therefore, the present study has focused on these in the buffer zone of Nanda Devi Biosphere Reserve. Seventy-six woody species (trees: 24; shrubs: 52) and 13 forest communities have been recorded between 2300–3800 m asl. Tree density ranged from 533–1220 ind ha-1, tree basal area from 14.68-80.28 m2ha-1 and shrub density from 1490–6695 ind ha-1. Mean density of trees was significantly lower in temperate forests in comparison to subalpine forests. Richness of trees ranged from 3–18 and shrubs from 5–29. Species diversity (H') of trees ranged from 0.45-2.08 and shrubs from 0.90-3.14. In the temperate zone, species richness and altitude had significant positive correlations whereas in the subalpine zone the two variables were negatively correlated. The native species were high in the area (> 65% species) and in communities (> 70% species), and was highest for the Picea smithiana-Pinus wallichiana mixed community, whereas the maximum numbers of natives and endemic species were recorded in the Pinus wallichiana community. The density and richness of non-natives were found to be significantly lower in comparison to the natives. Economic importance and conservation value of the communities were assessed and communities prioritized. Monitoring of the identified habitats, species, populations and communities, and development of appropriate strategies for their conservation and management are suggested. 相似文献
4.
Datta JK Sadhu S Gupta S Saha R Mondal NK Mukhopadhyay B 《Journal of environmental biology / Academy of Environmental Biology, India》2006,27(3):609-612
Cities and towns of the world are now facing enormous rise of noise pollution problem due to very high population rise, transport congestion and associated commercial and industrial activities. Burdwan, a district headquarter (100 km away from Kolkata) is one such town where noise pollution is very frequent. In order to assess noise level, noise data were collected from various places of the town by sound level meter with a duration of 30 minutes/location during specified time like 6.00 am, 10.00 am, 1.00 pm, 4.00 pm and 6.00 pm. Most of the monitoring places either belongs to silence category or commercial category areas. From the tabulated data, it was found that sound level lies within the range of 64-85 dB or above in different time at different places. The locations that belong to the silence zone have the noise level up to 90 dB. Statistically noise level in all these zones differ significantly at their peak hours. Noise pollution adversely affects our environment as well as human beings. Sound causes both pathological and psychological disorders in human beings. Implementation of rules and regulations under section 20, 21J, 41, 68(I), 70, 90, 111A of Environment Protection Act, 1986 and of course various technological methods and public awareness are very essential to check noise pollution in Burdwan town. 相似文献
5.
Arsenic in groundwater in six districts of West Bengal,India 总被引:9,自引:0,他引:9
Dipankar Das Gautam Samanta Badal Kumar Mandal Tarit Roy Chowdhury Chitta Ranjan Chanda Partha Pratim Chowdhury Gautam Kumar Basu Dipankar Chakraborti 《Environmental geochemistry and health》1996,18(1):5-15
Arsenic in groundwater above the WHO maximum permissible limit of 0.05 mg l–1 has been found in six districts of West Bengal covering an area of 34 000 km2 with a population of 30 million. At present, 37 administrative blocks by the side of the River Ganga and adjoining areas are affected. Areas affected by arsenic contamination in groundwater are all located in the upper delta plain, and are mostly in the abandoned meander belt. More than 800 000 people from 312 villages/wards are drinking arsenic contaminated water and amongst them at least 175 000 people show arsenical skin lesions. Thousands of tube-well water in these six districts have been analysed for arsenic species. Hair, nails, scales, urine, liver tissue analyses show elevated concentrations of arsenic in people drinking arsenic-contaminated water for a longer period. The source of the arsenic is geological. Bore-hole sediment analyses show high arsenic concentrations in only few soil layers which is found to be associated with iron-pyrites. Various social problems arise due to arsenical skin lesions in these districts. Malnutrition, poor socio-economic conditions, illiteracy, food habits and intake of arsenic-contaminated water for many years have aggravated the arsenic toxicity. In all these districts, major water demands are met from groundwater and the geochemical reaction, caused by high withdrawal of water may be the cause of arsenic leaching from the source. If alternative water resources are not utilised, a good percentage of the 30 million people of these six districts may suffer from arsenic toxicity in the near future. 相似文献
6.
SUMMARY Biodiversity of a protected area of West Himalaya (Askot Wildlife Sanctuary) was studied and analysed for landscape, faunal and floral diversity. The forest and pasture land, ideal habitats for the flora and fauna, covered nearly 52% and 12%, respectively, of total reported area. Among the fauna Himalayan musk deer (Moschus chrysogaster), thar (Himitragus jemlahicus), snow leopard (Panthera uncia), koklas (Pucrassia macrolophas), monal (Lophophorus impejanus) and snow cock (Tetragalus tibetanus) are threatened species. Plant diversity is represented by 1262 species of vascular plants (Angiosperm 1112, Gymnosperm 7, Pteridophytes 143 taxa). Diversity of the species within families, genera, habitats, communities and along vertical gradient zone was analysed. Maximum diversity existed in the family Orchidaceae (120 taxa), genera Polystichum (13 taxa), altitude zone (1001–2000 m; 860 taxa), habitat (forest; 623 taxa) and community (Banj oak: 92 taxa). Seventy-one families were found to be monotypic. Species were further analysed for ethnobotanical use (medicine: 70, edible: 55, fodder: 115, fuel: 31, house building: 13 etc.), domesticated diversity (crops: 19, vegetables: 26, fruits: 16), agroforestry or marginal, threatened and endemic diversity. Similarity in species composition within the habitats indicated maximum similarity in areas of shrubberies and alpine meadows/ slopes (71.65%) and exposed open/grassy slopes and shady moist places (47.32%). 432 (34.2%) taxa are native to Indian Himalaya of which 24 are endemic and 235 are near endemics. 65.8% of taxa are represented in the neighbouring areas and other regions of the globe. Ten taxa occurring in the Sanctuary have been already recorded in the Red Data Book of Indian Plants. Conservation and management of species is focused. 相似文献
7.
Tarafdar B Bhattacharyya RN 《Journal of environmental biology / Academy of Environmental Biology, India》2002,23(3):271-274
The present communication deals with the bacteriological examination of a pond water, which is being used as one of the sources of drinking water, by multiple tube fermentation test to detect the coliform bacteria. The test was performed sequentially in three stages: presumptive, confirmed and completed coliform test. The results show that as the most probable number (MPN) index per 100 ml is 23, that pond water should be treated as nonpotable. 相似文献
8.
9.
Increasing demand for water in domestic, agricultural, and industrial sectors necessitates exploitation of water either in the form of groundwater or from natural resources. To safeguard the long-term sustainability of water resources and their utilization, the quality of water has to be periodically monitored and determined for various characteristics, especially when the sources are polluted, such as Damodar river. Central Institute of Mining and Fuel Research (CIMFR), Dhanbad, is carrying out research work on coal and its utilization and associated environmental concerns. The blood stream of life for the whole Jharia Coalfield is none other than the river Damodar. CIMFR's campus also depends exclusively on river Damodar for meeting its demand of drinking water. This study is a general survey toward the characteristics of Damodar river water, with special emphasis on the pollutant parameters, and evaluation of the treatment process being carried out at the institute for potability. Damodar river water is indeed affected by the disposal of the wastes without any pre-treatment by different coal-based industries established in its basin. The quantity of dissolved and suspended solids, total hardness, chemical oxygen demand, and coliform bacterial count are higher in Damodar water due to the disposal of the waste/effluents from coal-washing plants, coke ovens, cement, and other industries, but well within the permissible limit which is probably attributable to the high-carrying capacity of the river. The river is still not that much affected as it is usually apprehended, and it can be well utilized for potable and domestic purposes after simple treatment. 相似文献
10.
Datta JK Chakraborty S Gupta S Saha RN Mondal N 《Journal of environmental biology / Academy of Environmental Biology, India》2007,28(1):11-14
In order to screen out the best variety of wheat (Triticum aestivum) out of eight varieties (viz., HP 1633, BW 11, NW 1014, Sonalika, HUW 468, K 9107, HP 1731 and HUW 234), a field experiment was conducted (from Dec. 2002 to April 2003) in a randomized block design replicated thrice at Crop Research and Seed Multiplication Farm, Burdwan University, West Bengal, India. Various morpho physiological parameters viz., plant population, length of shoot and root, leaf area index (LAI), crop growth rate (CGR), leaf area ratio (LAR), leaf area duration (LAD), net assimilation rate (NAR), yield attributes viz., length of panicles, number of grains per panicle, grain yield, straw yield, pigment content in flag leaf (chlorophyll a, b and total chlorophyll and carotenoid content) were estimated and analyzed statistically Soil bacterial populations were also estimated in the fallow land before sowing of seeds and after harvesting of crop. The HUW 468 variety records higher grain yield, maximum panicle length and maximum chlorophyll b and total chlorophyll content. 相似文献
11.
Bhadra B Chakraborty R Das S Nanda AK 《Journal of environmental biology / Academy of Environmental Biology, India》2005,26(2):277-286
Some physico-chemical parameters of Kaljani River were studied in and around Alipurduar municipality. The principal characteristics of Kaljani River are high TSS, Mg-hardness, COD, and Phosphate 'P' Comparison of water quality parameters of the two rivers demonstrated higher range of alkalinity, ammonia 'N' content and chloride content in Torsa than Kaljani. River Kaljani showed higher COD range than Torsa. Mean BOD value of both these rivers ranged between 0.93-1.65 mg/l. Overall TDS content of Kaljani was found to be lower than Torsa. Maximum phosphate 'P' content was observed at the downstream of both the rivers. 相似文献
12.
The Indian subcontinent is highly prone to the detrimental impacts of hazards viz. cyclones, floods and storm surges. Of late, these events have become extreme in nature and intensity. While occurrence and severity of the events is being linked to the phenomenon of climate change, their devastating potentialities are also getting triggered due to lack of resilience and coping capacity of the human community. That in turn depends on distribution of activities over the land i.e. land use pattern, affecting the socio -economic conditions directly. A coastal village often lacks infrastructural support, administrative attention and planning standards compared to a coastal city, thereby making it more vulnerable to disasters like flood. In a coastal city it is easy to govern and manage livelihood as land use depends highly on anthropogenic decisions. While in a coastal village, activities would highly depend on its natural characteristics viz. coastal geomorphology, soil, vegetation cover i.e. governance of livelihood by the eco-system. Hence, managing disaster through in-situ pro-active or developmental measures in a rural planning unit though imperative, is a challenging task. This paper focuses on spatial planning techniques for Restoration of ecological buffers and livelihood enhancement that would sustainably combat the impact of flood at village level in a coastal area. Geographic Information System (GIS) and Remote Sensing (RS) techniques have been used extensively in this study as application tools. 相似文献
13.
The opening in April 1994 of a deep artificial entrance channel into the shallow, microtidal and large Peel-Harvey Estuary (136 km2) in south-western Australia has led to major changes in the ichthyofauna of this system. This conclusion is based on statistical comparisons between data derived from samples of fish collected seasonally by seine net in the short, narrow and shallow natural entrance channel and in two large basins of the Peel-Harvey Estuary during 1996 and 1997, i.e. after the opening of the artificial channel, and data previously recorded seasonally using the same sampling regime during 1980 and 1981, i.e. before the construction of that channel. These comparisons show that the marked reduction in macroalgal growths that occurred between these two periods was accompanied by a decline in the abundance of fish, and particularly of macrophyte-associated species such as Pelates sexlineatus and Apogon rueppellii . There were also strong indications that the number of fish species usually present in the estuary declined, which would be consistent with a reduction in habitat heterogeneity. The comparisons also imply that the construction of the artificial channel led to: (1) a decline in the extent of interannual differences in the species richness and abundance of fish, presumably reflecting a reduction in the variability of environmental conditions in different years; (2) a greater penetration of the estuary by marine species and an increased contribution of these species to the fish fauna overall; (3) the influence of "season" on the ichthyofaunal compositions of assemblages within the estuary becoming more important than region. The second and third changes reflect a combination of increased tidal flow, which facilitates a more effective dispersal of fish, the exposure of fish to stronger tidal cues, a far greater proximity of the more distal regions of the estuary to the sea and, in the case of the third change, a far less pronounced difference between environmental conditions in the two basins. 相似文献
14.
Jha P Roy RP Barat S 《Journal of environmental biology / Academy of Environmental Biology, India》2010,31(5):587-594
Sensory and certain microbial analyses were applied to assess the quality of raw fish sold at a market in Siliguri cityof West Bengal, India. In regular surveys undertaken during June to August 2008, a particular fish species was randomly selected, its source was noted and a sensory analysis, the quality index method (QIM) was applied to assess its quality Raw fish samples were also collected and a small quantity (about 1 g) of scales oran upper layer of the skin surface (forscale-less fish samples), gill, liverand a portion of gut with gut-contents were aseptically removed for enumeration of the total aerobic heterotrophic bacteria, Aeromonas spp., Pseudomonas spp., Salmonella spp. and coliform counts. Oreochromis mossambicus and Tenulosa ilisha recorded significantly higher QIM scores, compared to other species (p<0.05). Riverine fish, Lepidocephalichthys guntea and Channa punctatus scored the lowest QIM scores (0) while scores for Puntius ticto and Mystus vittatus and pond cultured species like Cirrhinus mrigala, Catla catla, Labeo rohita, Labeo bata and Cyprinus carpio were very marginal (p<0.05). Aeromonas spp., Salmonella spp. and total coliforms were recorded from all the studied species while Pseudomonas spp. was isolated from only seven species. Among the tissues examined, the lowest counts of total heterotrophic bacteria, Aeromonas spp., Pseudomonas spp., Salmonella spp. and total coliforms were recorded from the skin in every fish species. Highest counts of pathogenic bacteria (except Pseudomonas spp.) were recorded in Tenulosa ilisha for all the tissues except liver. Since fish are properly cooked in Bengali households, the risk of disease from fish consumption is relatively less. However, some tribes residing in the region are known to consume undercooked fish and proper cooking methods should be followed in view of the present findings to avoid health risks. Besides, utmost care should be taken while handling fish. 相似文献
15.
Global warming impacts the water cycle not only by changing regional precipitation levels and temporal variability, but also by affecting water flows and soil moisture dynamics. In Brandenburg, increasing average annual temperature and decreasing precipitation in summer have already been observed. For this study, past trends and future effects of climate change on soil moisture dynamics in Brandenburg were investigated, considering regional and specific spatial impacts. Special Areas of Conservation (SACs) were focused on in particular. A decreasing trend in soil water content was shown for the past by analyzing simulation results from 1951 to 2003 using the integrated ecohydrological model SWIM [Krysanova, V., Müller-Wohlfeil, D.-I., Becker, A., 1998. Development and test of a spatially distributed hydrological/water quality model for mesoscale watersheds. Ecol. Model. 106, 261–289]. The trend was statistically significant for some areas, but not for the entire region. Simulated soil water content was particularly low in the extremely dry year 2003. Comparisons of simulated trends in soil moisture dynamics with trends in the average annual Palmer Drought Severity Index for the region showed largely congruent patterns, though the modeled soil moisture trends are characterized by a much higher spatial resolution. Regionally downscaled climate change projections representing the range between wetter and drier realizations were used to evaluate future trends of available soil water. A further decrease of average available soil water ranging from −4% to −15% was projected for all climate realizations up to the middle of the 21st century. An average decrease of more than 25 mm was simulated for 34% of the total area in the dry realization. Available soil water contents in SACs were generally higher and trends in soil moisture dynamics were lower mainly due to their favorable edaphic conditions. Stronger absolute and relative changes in the simulated trends for the past and future were shown for SACs within Brandenburg than for the state as a whole, indicating a high level of risk for many wetland areas. Nonetheless, soil water content in SACs is expected to remain higher than average under climate change conditions as well, and SACs therefore have an important buffer function under the projected climate change. They are thus essential for local climate and water regulation and their status as protected areas in Brandenburg should be preserved. 相似文献
16.
A. Vassilopoulos D. R. Green T. H. Gournelos N. Evelpidou P. Gkavakou S. Koussouris 《Journal of Coastal Conservation》2008,11(4):209-213
In this paper the counteractive dynamic marine and river environments responsible for a river mouth’s and a delta’s modulation is studied. The Acheloos River (West Greece) was chosen as the case study due to the recent changes taken place in its basin. The aim of this study is to analyze the present dominant environment and the impact of human activity on this balance. A GIS database was developed and updated in order to provide access for future use and computer analysis (both spatial and chronological). The study, includes an estimation of the delta forming processes, the impact of the anthropogenic parameters on these processes, and, finally, their representation. 相似文献
17.
Maity JP Nath B Kar S Chen CY Banerjee S Jean JS Liu MY Centeno JA Bhattacharya P Chang CL Santra SC 《Environmental geochemistry and health》2012,34(5):563-574
Drinking of arsenic (As)-contaminated groundwater has adverse effects on health of millions of people worldwide. This study aimed to determine the degree of severity of As exposure from drinking water in peri-urban Moyna and Ardebok villages, West Bengal, India. Arsenic concentrations in hair, nail and urine samp les of the individuals were determined. Arsenical dermatosis, keratosis and melanosis were investigated through medical evaluation. We have evaluated the association between As exposure from drinking water, and keratosis and melanosis outcomes. The results showed that 82.7?% of the sampled tube wells contain As concentrations above 10?μg/L, while 57.7?% contain As concentrations above 50?μg/L. The hair, nail and urine As concentrations were positively correlated with As concentrations in drinking water. In our study population, we observed a strong association between As concentrations ranging 51-99?μg/L and keratosis and melanosis outcomes, although the probability decreases at higher concentration ranges perhaps due to switching away from the use of As-contaminated tube wells for drinking and cooking purposes. High As concentrations in hair, nail and urine were observed to be associated with the age of the study population. The level of As concentrations in hair, nail and urine samples of the study population indicated the degree of severity of As exposure in the study region. 相似文献
18.
This research work is carried out to evaluate fluoride (F) hydrogeochemistry and its effect on the population of two endemic villages of Birbhum district, West Bengal. Fluoride concentration in drinking water varies from 0.33 to 18.08 mg/L. Hydrogeochemical evolution suggests that ion-exchange mechanism is the major controlling factor for releasing F in the groundwater. Most of the groundwater samples are undersaturated with respect to calcite and fluorite. Health survey shows that out of 235 people, 142 people suffer from dental fluorosis. According to fluoride impact severity, almost 80 and 94 % people in an age group of 11–20 and 41–50 suffer from dental and skeletal fluorosis, respectively. Statistically drinking water F has a positive correlation with dental and skeletal fluorosis. Bone mineral density test reveals that 33 and 45 % of the studied population suffer from osteopenic and osteoporosis disease. IQ test also signifies that F has a bearing on the intelligence development of the study area school children. The existence of significant linear relationship (R 2 = 0.77) between drinking water F and urinary F suggests that consumption of F-contaminated drinking water has a major control over urinary F (0.39–20.1 mg/L) excretion. 相似文献
19.
Using multistate mark-recapture methods to model adult salmonid migration in an industrialized river
A multistate mark-recapture (MSMR) model of the adult salmonid migration through the lower Columbia River and into the Snake River was developed, designed for radiotelemetry detections at dams and tributary mouths. The model focuses on upstream-directed travel, with states determined from observed fish movement patterns indicating directed upstream travel, downstream travel (fallback), and use of non-natal tributaries. The model was used to analyze telemetry data from 846 migrating adult spring-summer Chinook salmon (Oncorhynchus tshawytscha) tagged in 1996 at Bonneville Dam on the Columbia River. We used the model to test competing hypotheses regarding delayed effects of fallback at dams and visits to tributaries, and to define and estimate migration summary measures. Tagged fish had an average probability of 0.755 () of ending migration at a tributary or upstream of Lower Granite Dam on the Snake River, and a probability of 0.245 () of unaccountable loss (i.e., mortality or mainstem spawning) between the release site downstream of Bonneville Dam and Lower Granite Dam. The highest probability of unaccountable loss (0.092; ) was in the reach between Bonneville Dam and The Dalles Dam. Study fish used the tributaries primarily as exits from the hydrosystem, and visits to non-natal tributaries had no significant effect on subsequent movement upriver (P = 0.4245). However, fallback behavior had a small effect on subsequent tributary entry and exit (P = 0.0530), with fish using tributaries as resting areas after reascending Bonneville Dam after fallback. The spatial MSMR model developed here can be adapted to address additional questions about the interaction of migrating organisms with their environment, or for the study of migrations in other river systems. 相似文献
20.
Impact of payments for environmental services and protected areas on local livelihoods and forest conservation in northern Cambodia 总被引:1,自引:0,他引:1
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The potential impacts of payments for environmental services (PES) and protected areas (PAs) on environmental outcomes and local livelihoods in developing countries are contentious and have been widely debated. The available evidence is sparse, with few rigorous evaluations of the environmental and social impacts of PAs and particularly of PES. We measured the impacts on forests and human well‐being of three different PES programs instituted within two PAs in northern Cambodia, using a panel of intervention villages and matched controls. Both PES and PAs delivered additional environmental outcomes relative to the counterfactual: reducing deforestation rates significantly relative to controls. PAs increased security of access to land and forest resources for local households, benefiting forest resource users but restricting households’ ability to expand and diversify their agriculture. The impacts of PES on household well‐being were related to the magnitude of the payments provided. The two higher paying market‐linked PES programs had significant positive impacts, whereas a lower paying program that targeted biodiversity protection had no detectable effect on livelihoods, despite its positive environmental outcomes. Households that signed up for the higher paying PES programs, however, typically needed more capital assets; hence, they were less poor and more food secure than other villagers. Therefore, whereas the impacts of PAs on household well‐being were limited overall and varied between livelihood strategies, the PES programs had significant positive impacts on livelihoods for those that could afford to participate. Our results are consistent with theories that PES, when designed appropriately, can be a powerful new tool for delivering conservation goals whilst benefiting local people. 相似文献