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841.
Thomas WH 《Environmental management》2010,45(1):82-92
It has been proposed that indigenous societies can be models for the conservation of biodiversity. However, attempts at implementing
conservation-based development plans are being judged failures. In this article, I argue that these failures can be addressed
by translating indigenous knowledge into context that is mutually intelligible to both indigenous people and conservation
biologists. Drawing on sixteen months of ethnobiological fieldwork, this article uses indigenous knowledge to describe the
relationship of traditional life to biodiversity for the Hewa of Papua New Guinea’s Central Range. The island of New Guinea
is one of the planet’s last bastions of cultural and biological diversity. Using birds as an indicator of diversity, I argue
that more productive conservation policies will emerge when indigenous activities are viewed not as vehicles for establishing
equilibrium with the environment, but as a source of ecological disturbance. Although Hewa traditions currently play a significant
role in shaping this biologically diverse environment, their lifestyle is not necessarily a template for sustainability in
the future. 相似文献
842.
Paul B. Thompson 《Journal of Agricultural and Environmental Ethics》2010,23(3):209-227
Recent publications by Pogge (Global ethics: seminal essays. St. Paul: Paragon House 2008) and by Singer (The life you can save: acting now to end world poverty. New York: Random House 2009) have resuscitated a debate over the justifiability of famine relief between Singer and ecologist Garrett Hardin in the 1970s.
Yet that debate concluded with a general recognition that (a) general considerations of development ethics presented more
compelling ethical problems than famine relief; and (b) some form of development would be essential to avoiding the problems
of growth noted by Hardin. Better than renewing the debate, we should recognize two points. First, food needs do indeed evoke
a moral response that is more direct and compelling than the philosophical positions often generated to rationalize a duty
to bring aid. As such the argument for feeding hungry people cannot be generalized into a paradigm for development ethics
without distortions that undercut the morally valid elements in Singer’s original argument. Second, contrary to prevailing
assumptions in present day development ethics, food aid and famine relief continue to be important priorities for international
agencies, notably the World Food Program. Emergency food assistance, the nominal topic of Singer’s original article, thus
is an important issue for agricultural as well as development ethics, though one that should indeed be seen as distinct from
more complex duties to address the conditions of chronic poverty and underdevelopment. 相似文献
843.
Emma Ter Mors Mieneke W.H. Weenig Naomi Ellemers Dancker D.L. Daamen 《Journal of environmental psychology》2010,30(4):347-357
This experimental research addresses the effectiveness of communication about complex environmental issues, depending on whether the same information is provided by multiple collaborating or by individual organizations (i.e., stakeholders). The information provided pertains to carbon dioxide capture and storage (CCS) technology, as an example of a complex environmental issue. In Studies 1 (N = 75) and 2 (N = 66) we found that participants perceived factual information from collaborating stakeholders to be of higher quality than when the same information was provided by individual stakeholders. As predicted, the expectation of diverse perspectives being represented in the collaborative information mediated this effect. In addition, in Study 3 (N = 79) the perceived dissimilarity of collaborating stakeholders was shown to be an important precondition for the collaboration effect observed in Studies 1 and 2. Finally, these studies indicate that occasional collaboration between different stakeholders does not necessarily harm the perceived credibility of each individual stakeholder. 相似文献
844.
845.
A laboratory-scale bioremediation unit was designed, built and tested for the bio-removal of several Direct textile dyes.
Four experiments were carried out to assess the efficiency of the bioremediation unit using Aspergillus niger fungal strain. Three commonly used Direct dyes and textile dyes mixture (simulated effluent: Direct brown, Direct violet,
Direct green) were tested in this study. The strain of A. niger was efficient in the removal of the three Direct dyes. The decolorization percentages of the dyes after 24 h of incubation
were 56.2, 51.7, and 95.4% for Direct brown, Direct green, Direct violet dyes, respectively. The percentages increased up
to 79.4, 86.4, and 96.7% after 72 h of incubation for the same dyes, respectively. The results also showed that the fungal
strain reduced the chemical oxygen demand values of simulated dye effluents from 165 to 564 mg/l with most of the dyes. The
assessment of bioremediation products on biomodel was conducted using a fresh water fish. The liver and brain of Nile tilapia
were tested to evaluate the expression of genes coding for several proteins related to stress such as metallothioneins (MTs),
cytochrome P450 (CYP450), and heat shock proteins (HSPs). To assess the alterations in the gene expression, ten animals from
each group were killed after 4 weeks of treatment. The results revealed significant increases in the brain and hepatic mRNA
levels of all stress protein genes MT, CYP450, Hsp70a, b, and Hsp47 in the fish groups treated with industrial Direct violet,
green, and brown dye water. Exposure of tilapia to bioremediation products after treatment with A. niger fungi reduced the over-expression of the stress protein genes in the brain and liver tissues. 相似文献
846.
This work was undertaken to analyze nutrient contents of vegetation in an alpine meadow—Tungnath, North-West Himalaya, India.
The study pertains to the uptake, transfer and release of four main macronutrients (organic carbon, total nitrogen, total
potassium and total phosphorus) in grazed (exposed to extensive grazing by cattles) and ungrazed (grazing completely prohibited)
communities. Mineral concentration was recorded higher for the ungrazed sites compared to the grazed sites, and maximum standing
state of nutrients was found in roots. Belowground compartment (roots) contributed maximum share of mineral elements to soil.
Litter nutrients release was low because of low microbial activity and continuous removal of phytomass. Observations reveal
that there was very little amount of nutrient release from phytomass and vegetation in alpine are very poor source of mineral
recycling. Low transfer rate of minerals from one compartment to other is adequate for greater amount of these minerals that
are translocated back into the storage organs. A small proportion get removed through rain splash or through the removal of
hay during grazing as relatively high release rates in ungrazed sites when compared to grazed sites was observed. This translocation
can be considered as an important adaptation in alpine plants for survival during adverse environmental conditions, against
all types of biotic pressures and also for regeneration in the forthcoming growing season. 相似文献
847.
S. B. Debaje 《Environmental science and pollution research international》2014,21(12):7329-7338
In this study, we estimate yield losses and economic damage of two major crops (winter wheat and rabi rice) due to surface ozone (O3) exposure using hourly O3 concentrations for the period 2002–2007 in India. This study estimates crop yield losses according to two indices of O3 exposure: 7-h seasonal daytime (0900–1600 hours) mean measured O3 concentration (M7) and AOT40 (accumulation exposure of O3 concentration over a threshold of 40 parts per billion by volume during daylight hours (0700–1800 hours), established by field studies. Our results indicate that relative yield loss from 5 to 11 % (6–30 %) for winter wheat and 3–6 % (9–16 %) for rabi rice using M7 (AOT40) index of the mean total winter wheat 81 million metric tons (Mt) and rabi rice 12 Mt production per year for the period 2002–2007. The estimated mean crop production loss (CPL) for winter wheat are from 9 to 29 Mt, account for economic cost loss was from 1,222 to 4,091 million US$ annually. Similarly, the mean CPL for rabi rice are from 0.64 to 2.1 Mt, worth 86–276 million US$. Our calculated winter wheat and rabi rice losses agree well with previous results, providing the further evidence that large crop yield losses occurring in India due to current O3 concentration and further elevated O3 concentration in future may pose threat to food security. 相似文献
848.
Indira Gunaseelan B. Vijay Bhaskar K. Muthuchelian 《Environmental science and pollution research international》2014,21(13):8188-8197
Rainfall is a key link in the global water cycle and a proxy for changing climate; therefore, proper assessment of the urban environment’s impact on rainfall will be increasingly important in ongoing climate diagnostics and prediction. Aerosol optical depth (AOD) measurements on the monsoon seasons of the years 2008 to 2010 were made over four metro regional hotspots in India. The highest average of AOD was in the months of June and July for the four cities during 3 years and lowest was in September. Comparing the four regions, Kolkata was in the peak of aerosol contamination and Chennai was in least. Pearson correlation was made between AOD with climatic parameters. Some changes in the parameters were found during drought year. Temperature, cloud parameters, and humidity play an important role for the drought conditions. The role of aerosols, meteorological parameters, and their impacts towards the precipitation during the monsoon was studied. 相似文献
849.
850.
Ingrid H. Franke-Whittle Andreas Walter Christian Ebner Heribert Insam 《Waste management (New York, N.Y.)》2014,34(11):2080-2089
A study was conducted to determine whether differences in the levels of volatile fatty acids (VFAs) in anaerobic digester plants could result in variations in the indigenous methanogenic communities. Two digesters (one operated under mesophilic conditions, the other under thermophilic conditions) were monitored, and sampled at points where VFA levels were high, as well as when VFA levels were low. Physical and chemical parameters were measured, and the methanogenic diversity was screened using the phylogenetic microarray ANAEROCHIP. In addition, real-time PCR was used to quantify the presence of the different methanogenic genera in the sludge samples. Array results indicated that the archaeal communities in the different reactors were stable, and that changes in the VFA levels of the anaerobic digesters did not greatly alter the dominating methanogenic organisms. In contrast, the two digesters were found to harbour different dominating methanogenic communities, which appeared to remain stable over time. Real-time PCR results were inline with those of microarray analysis indicating only minimal changes in methanogen numbers during periods of high VFAs, however, revealed a greater diversity in methanogens than found with the array. 相似文献