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551.
L.S. Rawat R.K. Maikhuri Vikram S. Negi Abhay Bahuguna K.S. Rao Sunil K. Agarwal 《国际发展与全球生态学杂志》2013,20(5):423-430
Traditional Central Himalaya societies face a range of socio-economic and environmental problems. The potential of science and technology has not yet been adequately and appropriately harnessed to overcome the development constraints posed by the fragile Himalayan environment. Thus there is a need for large-scale establishment of technology resource centers. The Garhwal Unit of GB Pant Institute of Himalayan Environment and Development established rural technology demonstration and training centers in three different agroecological zones between 550 and 2200 m asl and in 13–15 locations, with suitable technologies based on appropriate use and management of locally available bio-resources that ensure people participation. About 35 on-site training courses were organised for about 2329 participants. The participants were given on-site demonstrations, training and technical know-how on various technologies, to enable farmers to better understand problems faced during implementation of new technologies for sustainable management of natural resources. An action research framework and training manuals were also developed in consideration of local socio-economic condition. The documentation and analysis of research (quantitative and qualitative) and data related to cost–benefit analysis of the technologies adopted by farmers generated through this study has created wider sharing of farmer training outputs, at farm level, amongst the scientific communities and with policy planners. 相似文献
552.
SUMMARY A rich diversity of traditional crops occurs generally in the Himalaya and more particularly in Central Himalaya. Over forty species of food grains are grown in traditional agroecosystems of Central Himalaya, which have been managed by the local farming communities since time immemorial. These traditional crop varieties have evolved over centuries and are well adapted to the particular area. A number of edaphic, topographic and climatic factors associated with different selection pressures over centuries of cultivation resulted in immense variations in the crop species. The grain and by-product yield of the majority of the traditional crops cultivated across an altitudinal gradient were worked out and compared with common food crops (paddy, wheat, mustard) at two points in time (1970-74, 1990–94) and it was found that almost all the traditional crops had slightly higher yields during 1970–74 than between 1990–94. However, common food crops grown during the Kharif season had higher yields during 1990–94 whereas, Rabi season crops exhibited higher yield during 1970–74. The yield of rainfed paddy remained static over the years across the altitudinal gradient. Among the traditional crops cultivated during the Kharif and Rabi seasons in mixed and pure forms at different altitudes were Macrotyloma uniforum (at higher altitude), Parilla frutescens and Vigna mungo (at middle altitude) and Panicum miliaceum (at lower altitude) which were found to be eco-energetically efficient. Avena sativa (oat) and mixed cropping of Fagopyrum esculentum and potato had higher energy efficiency ratios whereas the latter also exhibited a higher monetary output/input ratio. Crops like paddy and wheat with mustard, grown in irrigated land were found to be more eco-energetically efficient than the same crops grown in the rainfed land. In general, traditional crops possess higher nutritive value than the common food crops. The contribution of traditional crops to the local diet (kg/capita/year) and their energy and protein equivalents were higher during both time periods. It was observed that while exporting these traditional crops, the locals of the region are highly exploited by middlemen. Despite having huge potential, traditional crop diversity of this region has been reduced to a great extent during the last two decades. Besides, the area under cultivation with these crops has been declining rapidly. However, many of these crops possess immense potential to meet the growing food demand and ensure food security of an increasing population. Therefore, a comprehensive programme of conservation through various means and improvement of agronomic yield in their natural habitats is urgently needed. 相似文献
553.
Nannan Liu Mei Ma Yiping Xu Jinmiao Zha Kaifeng Rao Zijian Wang 《Frontiers of Environmental Science & Engineering》2013,7(1):77-84
2,4,6-trichlorophenol (2,4,6-TCP) is a widespread probable human carcinogen and has been proven to have genotoxicity in in vitro assays. However, little genotoxicity information and no micronuclei induction data for 2,4,6-TCP is available from in vivo tests, especially for sex-specific differences. Following a preliminary test, a piscine peripheral erythrocyte micronucleus assay was conducted on medaka (Oryzias latipes) after a 28-day exposure to 2,4,6-TCP. In the present study, the mean micronuclei (MNC) frequencies of all of the groups increased in a dose-dependent manner, which indicated the potential genotoxicity of 2,4,6-TCP. Moreover, males were found to be more susceptible compared with females after a 28-day exposure to 2,4,6-TCP in all of the dosed groups above 10 μg·L?1. This is the first report on the potential of micronuclei induction and a sex-susceptible effect in the peripheral erythrocytes of mature fish after 2,4,6-TCP in vivo exposure. 相似文献
554.
Robin Dennis Tyler Fox Montse Fuentes Alice Gilliland Steven Hanna Christian Hogrefe John Irwin S. Trivikrama Rao Richard Scheffe Kenneth Schere Douw Steyn Akula Venkatram 《Environmental Fluid Mechanics》2010,10(4):471-489
This paper discusses the need for critically evaluating regional-scale (~200–2,000 km) three-dimensional numerical photochemical air quality modeling systems to establish a model’s credibility in simulating the spatio-temporal features embedded in the observations. Because of limitations of currently used approaches for evaluating regional air quality models, a framework for model evaluation is introduced here for determining the suitability of a modeling system for a given application, distinguishing the performance between different models through confidence-testing of model results, guiding model development and analyzing the impacts of regulatory policy options. The framework identifies operational, diagnostic, dynamic, and probabilistic types of model evaluation. Operational evaluation techniques include statistical and graphical analyses aimed at determining whether model estimates are in agreement with the observations in an overall sense. Diagnostic evaluation focuses on process-oriented analyses to determine whether the individual processes and components of the model system are working correctly, both independently and in combination. Dynamic evaluation assesses the ability of the air quality model to simulate changes in air quality stemming from changes in source emissions and/or meteorology, the principal forces that drive the air quality model. Probabilistic evaluation attempts to assess the confidence that can be placed in model predictions using techniques such as ensemble modeling and Bayesian model averaging. The advantages of these types of model evaluation approaches are discussed in this paper. 相似文献
555.
The success of conserving biological resources in any Biosphere Reserve or protected area depends on the extent of support and positive attitudes and perceptions of local people have towards such establishments. Ignoring the dependence of the local people for their subsistence needs on resources of such areas leads to conflicts between protected area managers and the local inhabitants. Crop yield losses and livestock depredation were serious problems observed in most buffer zone villages of Nanda Devi Biosphere Reserve. In the present study 10 villages situated in the buffer zone of Nanada Devi Biosphere Reserve (1612 km2 area) in Chamoli district of Uttaranchal, India were studied during 1996-97 using a questionnaire survey of each household (419 = households; 2253 = total population in 1991; 273 ha = cultivated area). Estimates of crop yield losses were made using paired plots technique in four representative villages for each crop species. The magnitude of crop yield losses varied significantly with the distance of agricultural field from forest boundary. The total crop yield losses were high for wheat and potato in all the villages. The spatial distribution of total crop yield losses in any village indicated that they were highest in the area near to forest and least in the area near to village for all crops. Losses from areas near to forest contributed to more than 50% of total losses for each crop in all villages. However, in Lata, Peng and Tolma villages, the losses are high for kidney bean and chemmi (local variety of kidney bean) which varied between 18.5% to 30% of total losses in those villages. Potato alone represents 43.6% of total crop yield loss due to wildlife in Dronagiri village in monetary terms. Among the crops, the monetary value of yield losses are least for amaranth and highest for kidney bean. The projected total value of crop yield losses due to wildlife damage for buffer zone villages located in Garhwal Himalaya is about Rs. 538,620 (US$ 15,389). Besides food grains, horticultural crops i.e. apple, also suffered maximum damage. Major wildlife agents responsible for crop damage were wild boar, bear, porcupine, monkey, musk deer and partridge (chokor). Monkey and wild boar alone accounted for about 50% to 60% of total crop damage in the study villages. Goat and sheep are the major livestock killed by leopard. The total value of livestock losses at prevailing market rates is about Rs. 1,024,520 (US$ 29,272) in the study villages. Due to existing conservation policies and laxity in implementation of preventive measures, the problems for local inhabitants are increasing. Potential solutions discussed emphasize the need to undertake suitable and appropriate protective measures to minimize the crop losses. Change in cropping and crop composition, particularly cultivation of medicinal plants (high value low volume crops), were also suggested. Besides, fair and quick disbursement of compensation for crop loss and livestock killing need to be adopted. Local people of the buffer zone area already have a negative attitude towards park/reserve establishment due to socio-political changes inducing major economic losses and this attitude may lead to clashes and confrontations if proper ameliorative measures are not taken immediately. 相似文献
556.
Ravindranath N.H. Sudha P. Rao Sandhya 《Mitigation and Adaptation Strategies for Global Change》2001,6(3-4):233-256
A sustainable forestry scenario aimed at meeting the projected biomassdemands, halting deforestation and regenerating degraded forests wasdeveloped and analyzed for additionality of mitigation and cost-effectivenessfor India. Similarly, mitigation potential of a commercial forestry scenarioaimed at meeting the biomass demands from forestry activities on privateland was assessed. India has a significant scale baseline scenario afforestationand effective forest conservation activities. India is afforesting at an averagegross rate of 1.55 × 106 ha yr-1 over the past 10 years, while the gross deforestation rate was 0.272 × 106 ha yr-1 during the same period. The sustainable forestry scenario could lead to an additional carbon (C) stock of 237 × 106 Mg C during 2000 to 2012, while the commercial forestry scenario apart from meeting all the incremental biomass demands (estimated for 2000 to 2015) could potentially lead to an additional carbon stock of 78 × 106Mg C during 2000 to 2012. Short- and Long-rotation forestry activities arecommercially viable. With appropriate policies and financial incentives allthe industrial wood, sawnwood and commercial fuelwood requirementcould be met through commercial forestry, so that government funds couldbe dedicated for conserving state owned forests and meeting subsistencebiomass demands. The commercial forestry activities could receive financialsupport under greenhouse gas (GHG) abatement programmes. The government, however, needs to develop institutions and guidelines to process, evaluate, approve and monitor forestry sector mitigation projects. 相似文献
557.
A small study was undertaken to examine the microbiological characteristics of spent mushroom compost (SMC), which is the major waste by-product of the mushroom industry and which is regularly disposed off by application to agricultural land. The primary aim of this study was to examine SMC for the presence of faecal bacterial pathogens, including Campylobacter spp., Salmonella spp. and Listeria monocytogenes. Secondly it was desirable to quantify bacterial and fungal populations within SMC, and also qualitatively identify the diversity of bacterial populations within SMC, through employment of rDNA PCR and direct sequencing techniques on the culturable microflora. Conventional microbiological analyses of SMC material (n=30) from six commercial operations in both Northern Ireland and the Republic of Ireland, failed to detect Salmonella spp, Listeria spp. or Campylobacter spp. in any of the SMC material examined. Total aerobic plate counts gave a mean count of log10 7.01 colony forming units (cfu) per gram SMC material (range: log10 6.53-7.52 cfu/g). Fungal counts gave a mean count of log(10) 4.57 cfu per gram SMC material (range: log10 3.93-4.98 cfu/g). From a total of greater than 50 colony picks, a total of 12 bacterial morphotypes were identified and were further examined by employment of partial 16S rRNA gene amplification and sequencing techniques, yielding several genera and species, including Bacillus licheniformis, Bacillus subtilis, Klebsiella/Enterobacter sp. Microbacterium sp. Paenibacillus lentimorbus, Pseudomonas mevalonii, Sphingobacterium multivorum and Stenotrophomonas sp. This is the first preliminary report on the microbial diversity of SMC waste and demonstrates the presence of several species that have not been previously described in SMC, in addition to two potentially novel species within the genera Microbacterium and Stenotrophomonas. It is thereby important to examine the ecological microbe-microbe and plant-microbe interactions that are occurring between the native bacterial soil flora and those added annually (theoretically estimated at approximately 10(18) cells) through the application of SMC. Such studies would be beneficial in helping to ascertain the ecological consequences involved in the disposal of SMC waste on agricultural land. 相似文献
558.
Fractionation studies and bioaccumulation of sediment-bound heavy metals in Kolleru lake by edible fish 总被引:5,自引:0,他引:5
Chandra Sekhar K Chary NS Kamala CT Suman Raj DS Sreenivasa Rao A 《Environment international》2004,29(7):1001-1008
Kolleru lake is the largest fresh water lake in the districts of East and West Godavari of Andhra Pradesh, India. Many anthropogenic sources contribute to the heavy metal pollution in the lake and the bioaccumulation of heavy metals in fish helps in assessing the aquatic pollution. Total contents and fractionation of selected heavy metals, viz., Zn, Cu, Cd, Pb, Cr, Ni and Co were measured in sediment sample and three edible fish. The investigation aimed at revealing differences in the accumulation pattern of heavy metals in fish inhabiting sediments characterized by varying metal bioavailability. The metal concentrations were found to be greater than the background concentrations of sediments indicating the anthropogenic origin of metals. Good recovery values were obtained for metal contents in sediments and fish. Large fractions of Zn, Cd and Cu were associated with mobile fraction of sediment and showed greater bioaccumulation in fish whereas Ni and Co were least mobilisable. The results clearly indicate that the fish of Kolleru lake are contaminated with metals and not advisable for human consumption. 相似文献
559.
Hymavathi V Rao LM 《Journal of environmental biology / Academy of Environmental Biology, India》2001,22(3):209-212
The present study deals with the biochemical composition of Channa orientalis from a habitat polluted by slaughter house wastes in comparison to an unpolluted habitat of Mudasarlova stream of Visakhapatnam. The total proteins, carbohydrates and lipids were found to be less in the organisms collected from the polluted habitat. The probable reasons for these variations are discussed in detail. 相似文献
560.