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1.
Traditional knowledge and practices are important in prudent resource use and biodiversity conservation. The implications of modernization and changing lifestyle are discussed in the context of agriculture and resource use, the two sectors in which maximum modernization has occurred. The information was gathered through observations and structured interviews over three years (July 1996 to July 1999) of field work in the western Himalaya. It was observed that forest based subsistence agriculture has given way to the market dependant cash crop cultivation. That apart from loss of genetic diversity, has also resulted in the degradation of forests. The use of wild plants in the day-to-day activities has also declined and dependence on high value market products has increased. Currently, wild plants are used only if no other cheap substitute is available in the market or if the use is economically beneficial to the people. Thus, the knowledge gathered through ages of experience is eroding because of the activities geared for short-term economic benefits which, in long run, may not be sustainable.  相似文献   
2.
Biodiversity conservation in developing countries has been a challenge because of the combination of rising human populations, rapid technological advances, severe social hardships, and extreme poverty. To address the social, economic, and ecological limitations of people-free parks and reserves, incentives have been incorporated into conservation programs in the hopes of making conservation meaningful to local people. However, such incentive-based programs have been implemented with little consideration for their ability to fulfill promises of greater protection of biodiversity. Evaluations of incentive-based conservation programs indicate that the approach continually falls short of the rhetoric. This article provides an overview of the problems associated with incentive-based conservation approaches in developing countries. It argues that existing incentive-based programs (IBPs) have yet to realize that benefits vary greatly at different “community” scales and that a holistic conceptualization of a community is essential to incorporate the complexities of a heterogeneous community when designing and implementing the IBPs. The spatial complexities involved in correctly identifying the beneficiaries in a community and the short-term focus of IBPs are two major challenges for sustaining conservation efforts. The article suggests improvements in three key areas: accurate identification of “target” beneficiaries, greater inclusion of marginal communities, and efforts to enhance community aptitudes.  相似文献   
3.
Environmental Science and Pollution Research - The aquaculture industry is an efficient edible protein producer and grows faster than any other food sector. Therefore, it requires enormous amounts...  相似文献   
4.
SUMMARY

The search for innovative methods for improving relations between parks and people has led to various conservation and development projects around the world. Nepal's almost three decades of experience in park management in a variety of institutional settings offers valuable lessons in the challenges and opportunities for enlisting local support for conservation. Citing several macro and micro-level case studies from around the country, this paper provides a comparative perspective on the significance of tourism-focused conservation and community development activities in resolving conflicts between parks and local people.  相似文献   
5.
This study presents distribution of organochlorines (OCs) including HCH, DDT and PCBs in urban soils, and their environmental and human health risk. Forty-eight soil samples were extracted using ultrasonication, cleaned with modified silica gel chromatography and analyzed by GC-ECD. The observed concentrations of ∑HCH, ∑DDT and ∑PCBs in soils ranged between?<?0.01–2.54, 1.30–27.41 and?<?0.01–62.8 µg kg?1, respectively, which were lower than the recommended soil quality guidelines. Human health risk was estimated following recommended guidelines. Lifetime average daily dose (LADD), non-cancer risk or hazard quotient (HQ) and incremental lifetime cancer risk (ILCR) for humans due to individual and total OCs were estimated and presented. Estimated LADD were lower than acceptable daily intake and reference dose. Human health risk estimates were lower than safe limit of non-cancer risk (HQ?<?1.0) and the acceptable distribution range of ILCR (10?6–10?4). Therefore, this study concluded that present levels of OCs (HCH, DDT and PCBs) in studied soils were low, and subsequently posed low health risk to human population in the study area.  相似文献   
6.
Rice is a major food crop throughout the world; however, accumulation of toxic metals and metalloids in grains in contaminated environments is a matter of growing concern. Field experiments were conducted to analyze the growth performance, elemental composition (Fe, Si, Zn, Mn, Cu, Ni, Cd and As) and yield of the rice plants (Oryza sativa L. cv. Saryu-52) grown under different doses of fly-ash (FA; applied @ 10 and 100 tha(-1) denoted as FA(10) and FA(100), respectively) mixed with garden soil (GS) in combination with nitrogen fertilizer (NF; applied @ 90 and 120 kg ha(-1) denoted as NF(90) and NF(120), respectively) and blue green algae biofertilizer (BGA; applied @ 12.5 kg ha(-1) denoted as BGA(12.5)). Significant enhancement of growth was observed in the plants growing on amended soils as compared to GS and best response was obtained in amendment of FA(10)+NF(90)+BGA(12.5). Accumulation of Si, Fe, Zn and Mn was higher than Cu, Cd, Ni and As. Arsenic accumulation was detected only in FA(100) and its amendments. Inoculation of BGA(12.5) caused slight reduction in Cd, Ni and As content of plants as compared to NF(120) amendment. The high levels of stress inducible non-protein thiols (NP-SH) and cysteine in FA(100) were decreased by application of NF and BGA indicating stress amelioration. Study suggests integrated use of FA, BGA and NF for improved growth, yield and mineral composition of the rice plants besides reducing the high demand of nitrogen fertilizers.  相似文献   
7.
Recognizing the array of effects that invasive alien species have, documenting their status from biodiversity rich regions has been much emphasized. Lack of such studies is a major limitation that hampers proper management of alien species. The present paper, therefore, documents the alien flora of the Indian Himalayan state of Himachal Pradesh (HP) based on data obtained from literature and herbarium records. The alien flora of HP comprises of 497 species belonging to 85 families. Majority of them belong to family Asteraceae (59 species), followed by Poaceae (47 species) and Fabaceae (43 species). Amongst the genera, Ipomoea (9 species), Eucalyptus and Euphorbia (7 species each) are the most predominant. Herbs constitute the majority (i.e., 73 %) of alien species and a large percentage of them (i.e., 22.94 %) have South America as their native region. Further, of the total alien species, 248 are intentional introductions and majority (31 % species) have been introduced for ornamental purposes. It was revealed that 34 % species have naturalized while 29 % species have become invasive. Today, in addition to human-disturbed landscapes, alien species have also been reported from dense forests. Himalaya being a biodiversity hotspot and HP being a bio-rich Himalayan state, it is hoped that this inventory and assessment of alien flora will help in designing informed management and monitoring strategies against problematic plant invasions in the state.  相似文献   
8.
Taxus wallichiana Zucc. (Himalayan yew) represents one of the most threatened medicinal tree species of the Himalayan region. Heavy exploitation of its bark and leaves for taxol® has resulted in decline in its population. Generating quantitative information on Himalayan yew has therefore been stressed. The present paper provides information on the population and bark removal of Himalayan yew from one of the interior areas of Himalaya. Total count and quadrat method were deployed to generate quantitative information on its population while bark removal was estimated based on depth and extent of bark removed. After analyzing the existing information and the results of the study, a rapid vulnerability assessment (RVA) of the species was carried out. Taxus reported a density of 72 individuals/ha and was present as an under canopy of Picea smithiana. Complete stripping of bark was observed in 11 % of the Taxus population which amounted to ca. 18,152.86 cm3 of bark removed. The age class distribution showed complete absence of seedlings and saplings. RVA scores also reported higher values (26) thereby pointing toward the high vulnerability of this species. Across its entire distributional range, Taxus population is under severe pressure. It is high time when few patches of Taxus are demarcated as Medicinal Plant Conservation Areas, and detailed studies on its autecology are initiated.  相似文献   
9.
The present paper quantifies and reviews the natural resource use in the Himalayan state of Himachal Pradesh (HP). Twenty-five percent of the geographical area of HP is under forests and harbour ca. 3,400 plant species. The available bioresources not only support the livelihood of nearly 6 million people but also fulfill the forage requirement of 5.2 million livestock. Thus, dependence on bioresources is manifold. Based on field surveys to different localities of HP and analyses of published information, two types of resource use patterns have been identified. One, the direct use of forest resources which is represented by extraction of timber, fuelwood and fodder; and the second represents indirect resource use from the forest that is represented by activities related to agriculture, tourism and industry. Amongst the direct resource use, annual timber requirement of the local people works out to be 310,063 m(3). On the other hand, annual fuelwood and fodder requirement of local people is to the tune of 3,646,348.8 and 10,294,116.5 tons, respectively. Extraction of fodder therefore appears to be one of the main reasons for forest degradation in HP as opposed to timber and fuelwood extraction. However, compared to direct resource use, indirect resource use and pressures have far more pronounced effect on the forests. Of the indirect pressures, shifts in agriculture patterns and increased tourism seem to be the most prominent.  相似文献   
10.
Arsenic (As) is a widespread environmental and food chain contaminant and class I, non-threshold carcinogen. Plants accumulate As due to ionic mimicry that is of importance as a measure of phytoremediation but of concern due to the use of plants in alternative medicine. The present study investigated As accumulation in native plants including some medicinal plants, from three districts [Chinsurah (Hoogly), Porbosthali (Bardhman), and Birnagar (Nadia)] of West Bengal, India, having a history of As pollution. A site-specific response was observed for Specific Arsenic Uptake (SAU; mg kg(-1) dw) in total number of 13 (8 aquatic and 5 terrestrial) collected plants. SAU was higher in aquatic plants (5-60 mg kg(-1) dw) than in terrestrial species (4-19 mg kg(-1) dw). The level of As was lower in medicinal plants (MPs) than in non-medicinal plants, however it was still beyond the WHO permissible limit (1 mg kg(-1) dw). The concentration of other elements (Cu, Zn, Se, and Pb) was found to be within prescribed limits in medicinal plants (MP). Among the aquatic plants, Marsilea showed the highest SAU (avg. 45 mg kg(-1) dw), however, transfer factor (TF) of As was the maximum in Centella asiatica (MP, avg. 1). Among the terrestrial plants, the maximum SAU and TF were demonstrated by Alternanthera ficoidea (avg. 15) and Phyllanthus amarus (MP, avg. 1.27), respectively. In conclusion, the direct use of MP or their by products for humans should not be practiced without proper regulation. In other way, one fern species (Marsilea) and some aquatic plants (Eichhornia crassipes and Cyperus difformis) might be suitable candidates for As phytoremediation of paddy fields.  相似文献   
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