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91.
Forest cover is viewed as a resource for the nation as it provides ecosystem services. However, it becomes a burden and retards development for the people of the area, particularly the hills, where such forests flourish. Enactment of stringent laws over the past few decades has strictly prohibited tree felling in these areas, and it has become a deterrent in their growth process. While on one hand, the plains are abuzz with economic activity, on the other hand, the sparse population of the hills is compelled to bear the responsibility of maintaining ecological balance. In this context, the issue of development along with forest sustainability becomes important. Using the case study of the hills of Uttarakhand, India, the paper attempts to highlight the problems and the possible strategies that may be adopted to facilitate inclusive socioeconomic development of forest dwellers while ensuring conservation and enhancement of forest cover.  相似文献   
92.
Human data on the relationship of semen quality with pesticide and metals are mostly inconsistent. The purpose of the study is to confirm the toxicity of organochlorine pesticide β- and γ-hexachlorocyclohexane (HCH), DDE and DDD, and metals lead or cadmium on sperm motility in epidemiological study among fertile and infertile men and to determine whether in vivo and in vitro results are in the same direction. Semen analysis and estimation of the toxicants were done in 60 fertile and 150 infertile men. In the in vitro studies, sperm were exposed to the highest levels of these toxicants found in vivo, as well as five and ten times higher, and to the mixture of all compounds. The study assesses sperm viability and motility for a period ranging between 30 min and 96 h. Epidemiological data showed an inverse correlation of toxicant with sperm motility. In vitro study showed that γ-HCH and lead after 12 h, cadmium after 8 h, and coexposure to toxicants after 6 h of exposure caused significant concentration- and duration-dependent decline in sperm motility. Data of in vitro study were concurrent with epidemiological finding that might be useful in establishing the possible association between exposure and effect of these selected pollutants on sperm motility.  相似文献   
93.
Transgenic Bt crops produce insecticidal Cry proteins that are released to soil in plant residues, root exudates, and pollen and that may affect soil microorganisms. As a continuation of studies in the laboratory and a plant-growth room, a field study was conducted at the Rosemount Experiment Station of the University of Minnesota. Three Bt corn varieties that express the Cry1Ab protein, which is toxic to the European corn borer (Ostrinia nubilalis Hübner), and one Bt corn variety that expresses the Cry3Bb1 protein, which is toxic to the corn rootworm complex (Diabrotica spp.), and their near-isogenic non-Bt varieties were evaluated for their effects on microbial diversity by classical dilution plating and molecular (polymerase chain reaction-denaturing gradient gel electrophoresis) techniques and for the activities of some enzymes (arylsulfatases, acid and alkaline phosphatases, dehydrogenases, and proteases) involved in the degradation of plant biomass. After 4 consecutive years of corn cultivation (2003-2006), there were, in general, no consistent statistically significant differences in the numbers of different groups of microorganisms, the activities of the enzymes, and the pH between soils planted with Bt and non-Bt corn. Numbers and types of microorganisms and enzyme activities differed with season and with the varieties of corn, but these differences were not related to the presence of the Cry proteins in soil. The Cry1Ab protein of Bt corn (events Bt11 and MON810) was detected in most soils during the 4 yr, whereas the Cry3Bb1 protein was not detected in soils of Bt corn (event MON863) expressing the cry3Bb1 gene.  相似文献   
94.
A system dynamics model based on the dynamic interactions among a number of system components is developed to estimate CO(2) emissions from the cement industry in India. The CO(2) emissions are projected to reach 396.89 million tonnes by the year 2020 if the existing cement making technological options are followed. Policy options of population growth stabilisation, energy conservation and structural management in cement manufacturing processes are incorporated for developing the CO(2) mitigation scenarios. A 42% reduction in the CO(2) emissions can be achieved in the year 2020 based on an integrated mitigation scenario. Indirect CO(2) emissions from the transport of raw materials to the cement plants and finished product to market are also estimated.  相似文献   
95.
Environmental Science and Pollution Research - In this study,?~?40 nm anatase TiO2 nanoparticles were successfully prepared by a simple electrochemical method by using succinic...  相似文献   
96.
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   
97.
Anabaena and Aulosira fertilissima showed a marked ability to accumulate DDT, fenitrothion and chlorpyrifos. Although the maximum accumulation of DDT was almost the same in both organisms, there were significant differences in their abilities to accumulate fenitrothion and chlorpyrifos. Patterns of uptake of DDT under different treatments were also similar in both Anabaena and Aulosira, but there were significant differences in the patterns of accumulation of fenitrothion between these two organisms. In Aulosira the maximum accumulation of fenitrothion was observed on the second day, whereas, in Anabaena, maximum accumulation was noticed on the first day. A completely different pattern of accumulation of chlorpyrifos was observed in Aulosira, which continued to accumulate chlorpyrifos throughout the experimental period. Bioconcentration of DDT in Anabaena and Aulosira ranged from 3 to 1568 ppm (microg g(-1)) and 6 to 1429 ppm, respectively. Bioconcentration of fenitrothion and chlorpyrifos in Anabaena varied from 53 to 3467 ppm and 7 to 6779 ppm, respectively. In Aulosira the bioconcentration varied from 100 to 6651 ppm and 53 to 3971 ppm for fenitrothion and chlorpyrifos, respectively. Anabaena and Aulosira metabolised DDT to DDD and DDE. Amounts of these DDT metabolites detected in the organisms were dependent on the concentration of treatment. DDD was the major, and DDE the minor, metabolite. These organisms were not able to metabolise the organophosphorus insecticides, fenitrothion and chlorpyrifos.  相似文献   
98.
A nonequilibrium-reaetion model is developed to predict the flue gas composition of an incinerator for solid waste combustion and gasification. The model may also be effectively utilized to predict the composition of exit gas from the primary chamber of an incinerator where invariably substoichiometrie combustion conditions exist The model assumes that the drying and pyrolysis of waste occurs in sequence followed by combustion of devolatilized gas and residue separately. The model is applied to the combustion of pine wood, and the flue gas compositions are computed as a function of operating parameters such as temperature (1100 to 1500 K), initial moisture content (0 to 40 percent), and percentage excess air (up to 100 percent). The model is extended to include substoichiometric combustion (to simulate the gasification process without steam injection) to compare its predictions with the available experimental data. The general agreement of theory and experiment is good.  相似文献   
99.
Twelve new ortho-Hydroxyketimines were synthesized by conventional as well as microwave method and evaluated for their antinemic activity against Meloidogyne incognita [(Kofoid and White) Chitwood]. Conventional methods for synthesis of Schiff bases require refluxing at 140°C of the reactants in different solvents for at least 24 h or more, where as the microwave-assisted synthesis has brought down the reaction time from 24 h to 1 minute. The procedure reported is simple as it does not require any organic solvents and the time has been reduced to only 1 minute. Comparative yields of all compounds by different methods revealed that the yield was low in conventional method (79–87%) as compared to microwave assisted synthesis (94–97%). The bioassay revealed that all the test compounds exhibited promising nematicidal activity; N-propyl-2-hydroxypropiophenonimine being the most effective with LC50 value of 74.46 mgL?1 followed by N-hexyl-2-hydroxyacetophenonimine with LC50 value of 99.60 mgL?1 after 72 h of exposure. The results obtained from bioassay indicated that this class of compounds has not only given a lead with regard to potential of Schiff bases in pest control, but has suggested that a carbon chain length of 6 atoms in the side chain is optimum on the basis of structure activity relationship (SAR).  相似文献   
100.
Present investigations were carried out on the limnological aspects of Texi temple pond in district Etawah. Many of the parameters were found below the permissible limits for drinking water as suggested by WHO. A total of 18 parameters were analysed and their seasonal variations in the year 2003 were discussed.  相似文献   
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