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211.
The present paper examines the nature and dimensions of environmental transformation induced by canal irrigation in the arid region of India. The case study pertains to the Indira Gandhi Canal comand area in Rajasthan where the density and area of vegetation cover have increased due to afforestation, and the cultivated area has expanded due to irrigation. Consequently, there has been a perceptible improvement in the structure and fertility of sandy soils, but it would require a herculean effort on the part of the canal authority and local people to reduce soil erosion and siltation in the lower parts of stage I and the entire command area of stage II. Moreover, the water table has been rising rapidly throughout the command area of stage I. About half of the command area and adjoining Ghaggar basin in Ganganagar District will be facing the danger of waterlogging by the turn of the century. The incidence of irrigation-induced alkalization is higher in the lower parts of stage I. Soil alkalinity has appeared within five years of the introduction of irrigation in the interdunal basins and is manifested as a strong salt regime or calcareous pans near surface. This calls for immediate reclamation of the affected area and prevention of its expansion by altering the strategy of irrigation development, by changing cropping patterns, and by providing soil drainage. 相似文献
212.
Pallav Purohit Axel Michaelowa 《Mitigation and Adaptation Strategies for Global Change》2008,13(1):23-46
In view of the increasing interest in the development and dissemination of technologies for harnessing new and renewable sources
of energy in India, there have also been some efforts towards their use in the domestic lighting sector. However, the cumulative
number of Solar Photovoltaic (SPV) lighting systems such as SPV lanterns and solar home lighting systems in India is far below
their theoretical potential despite government subsidy programmes. One of the major barriers is the high capital investment
in these systems. The Clean Development Mechanism (CDM) provides industrialized countries with an incentive to invest in emission
reduction projects in developing countries to achieve a reduction in CO2 emissions at lowest cost that also promotes sustainable development in the host country. SPV lanterns and solar home lighting
systems could be of interest under the CDM because they directly displace greenhouse gas emissions while contributing to sustainable
rural development. However, only two SPV projects have been submitted under the CDM so far. This study assesses the maximum
theoretical as well as the realistically achievable CDM potential of SPV lanterns and solar home lighting systems in India.
The SPV lantern project is financially viable at a certified emissions reductions (CER) price of 34 € whereas the solar home
lighting project is financially viable at a CER price of 46 €. While the maximum mitigation volume is about 35 million tonne
CO2 on an annual basis, an estimate of achievable CER levels is done using the past diffusion trends of SPV systems. We find
that annual CER volumes could reach 0.8 to 2.4 million by 2012 and 5.6 to 13.6 million by 2020. This would require that the
government sets the subsidy level for SPV lighting systems at a level that allows them to become viable with the CER revenue.
From a macro-economic point of view this makes sense if the sustainability benefits are deemed sufficiently high to warrant
promotion of this type of project.
相似文献
Axel MichaelowaEmail: |
213.
Occurrence, distribution and possible sources of organochlorine pesticide residues in tropical coastal environment of India: an overview 总被引:2,自引:0,他引:2
Sarkar SK Bhattacharya BD Bhattacharya A Chatterjee M Alam A Satpathy KK Jonathan MP 《Environment international》2008,34(7):1062-1071
Organochlorine pesticides (OCPs) are an important potential component of chemical pollutants used extensively for agriculture and sanitation purposes in India as these are comparatively cheap and effective. These persistent organic compounds such as HCH isomers, DDT and its metabolites are the predominant chemical contaminants found along the Indian coast and thus constitute both alluring and grave areas of scientific research. Our objective in the paper is to provide a comprehensive account of the distribution of organochlorine pesticides in biotic and abiotic compartments of the Indian coastal environment, make some comments on their environmental sources, their movement through the food chain and possible ecotoxicological risk of health in biota including humans. The prevalent HCH, DDT and HCB concentrations differ markedly in eastern and western coast of India reflecting differing agricultural and other usage and their ultimate input into the coastal environment by several rivers and the bioturbation activities of macrozoobenthos (bivalve mollusks, polychaetous annelids, etc.). In several cases, the DDT levels exceeded the effects range-low (ER-L) and could thus cause acute biological impairments, in comparison with the sediment quality guidelines. Contributions of DDT metabolites (DDT, DDD and DDE residues) vary in different Indian coastal regions predominated by pp'-DDT and pp'-DDD. Measured concentrations of HCHs were lower than DDTs that might be due to higher water solubility, vapor pressure and biodegradability of the latter. HCH and DDT residues in fish in India were lower than those in the temperate countries indicating a lower accumulation in tropical fish, which might be related to rapid volatilization of this insecticide in the tropical environment. The concentrations of other chlorinated pesticides (aldrin, dieldrin, eldrin, methoxychlor, endosulfan sulphate) were lower and not generally of great concern. 相似文献
214.
Patel KS Shrivas K Brandt R Jakubowski N Corns W Hoffmann P 《Environmental geochemistry and health》2005,27(2):131-145
Arsenic contamination in the environment (i.e. surface, well and tube-well water, soil, sediment and rice samples) of central
India (i.e. Ambagarh Chauki, Chhattisgarh) is reported. The concentration of the total arsenic in the samples i.e. water (n=64), soil (n=30), sediment (n=27) and rice grain (n=10) were ranged from 15 to 825 μg L−1, 9 to 390 mg kg−1, 19 to 489 mg kg−1 and 0.018 to 0.446 mg kg−1, respectively. In all type of waters, the arsenic levels exceeded the permissible limit, 10 μg L−1. The most toxic and mobile inorganic species i.e. As(III) and As(V) are predominantly present in water of this region. The
soils have relatively higher contents of arsenic and other elements i.e. Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu,
Zn, As, Ga, Zr, Sn, Sb, Pb and U. The mean arsenic contents in soil of this region are much higher than in arsenic soil of
West Bengal and Bangladesh. The lowest level of arsenic in the soil of this region is 3.7 mg kg−1 with median value of 9.5 mg kg−1. The arsenic contents in the sediments are at least 2-folds higher than in the soil. The sources of arsenic contamination
in the soil of this region are expected from the rock weathering as well as the atmospheric deposition. The environmental
samples i.e. water, soil dust, food, etc. are expected the major exposure for the arsenic contamination. The most of people
living in this region are suffering with arsenic borne diseases (i.e. melanosis, keratosis, skin cancer, etc.). 相似文献
215.
Political Incentives for Biodiversity Conservation 总被引:2,自引:0,他引:2
Abstract: There seems to be a worldwide lack of political will for conservation that leads, inevitably, to an undermining of conservation policy. This is a standard complaint but one that has received little academic attention. In an attempt to better understand the gap between conservation policy and practice, we examined conservation policies and practice as they have played out in the Great Himalayan National Park, Himachal Pradesh, India, over the past two decades. In particular we consider the park's experience within two larger contexts: (1) Himachal's current development orientation, which seeks to transform the state into the electrical powerhouse of the country by building over 300 medium and large power projects and (2) electoral politics that result in politician's support for villagers and others denied access to national parks and wildlife sanctuaries. Each of these factors works to undermine state conservation policies. Conservationists need to build political bridges with local communities if they are to use electoral power to work for rather than against conservation. Only such electoral power can be expected to force governments to adopt more cautious policies in advancing a particular development agenda. In the absence of strategic alignments in places such as Himachal Pradesh with strong democratic traditions, one must expect continued political support for potentially destructive megaprojects and an absence of political support for the conservation of biological diversity. 相似文献
216.
217.
Cold season (winter and thaw) CH4, CO2 and N2O fluxes from freshwater marshes (47°35′N, 133°31′E, Northeast China) were measured, using the static chamber method. The mean CH4 and CO2 fluxes from Carex lasiocarpa (Cl) were 0.5 ± 0.19 and 6.23 ± 1.36 mg C m−2 h−1, respectively, and those from Deyeuxia angustifoli (Da) were 0.18 ± 0.15 and 5.22 ± 2.48 mg C m−2 h−1, respectively in winter. There was no significant difference between Cl and Da (p > 0.05). The contributions of winter CH4 fluxes were about 5.5% and 3% in the Cl and Da, respectively. Marshes are an important potential N2O sink in winter season in northeast China. During thaw, the CH4 and CO2 emissions rapidly increased, 4.5–6 times of winter emissions. Wetland became a source of N2O. Cold season gases flux from northern wetlands play an important role in the seasonal gas exchange. 相似文献
218.
219.
Smita Sirohi Axel Michaelowa S. K. Sirohi 《Mitigation and Adaptation Strategies for Global Change》2007,12(2):259-274
Enteric fermentation in livestock is an important source of anthropogenic methane emission. India, with its large livestock
population, is estimated to contribute 10.8 Tg of methane annually from this source. An evaluation of various methane mitigation
options indicate that some of the available technologies like, diet supplementation with feed additive and molasses urea product
are highly cost effective in reducing enteric methane emissions. The gross cost of methane abatement from use of feed additive
monensin premix ranges from €0.6 to €1.8/ton CO2 equivalent, for buffaloes and indigenous cows, respectively. The gross cost of enteric methane mitigation from supplementing
molasses urea products and dietary manipulation through increased concentrate feeding is much higher. But, as the monetary
value of the increased milk production on application of these technologies was higher than the annual cost of reduction strategy
for buffaloes and crossbred cows, the net costs of the former mitigation option was negative for buffaloes (€-28.1/ton CO2) and of the latter for crossbred cows (€-7.0/ton CO2,). The availability of cost-effective technologies suggest that the methane mitigation projects under CDM, can be planned
in the Indian dairy sector to the mutual benefit of countries with emission targets and India. The vast dairy animal population
of India and resulting methane emissions provide good opportunity these countries to buy reasonable quantum of emission credits
from projects in India. Such projects will work to the benefit to India by providing a tool for technology transfer to increase
animal productivity and attract capital that assists in more prosperous and environmental friendly milk production in the
country. 相似文献
220.