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971.
Regular fuel reduction burning is an important management strategy for reducing the scale and intensity of wildfires in south-west
Australian native forests, but the long term effects of this on tree and stand growth are not well understood. Five fire treatments,
including application of frequent and infrequent low intensity burns, and 25 years of fire exclusion, were applied to small
(4 ha) experimental plots in a low rainfall mixed jarrah (Eucalyptus marginata) and marri (Corymbia calophylla) forest to investigate the effects of these treatments on tree stem diameter growth, stand basal area increment and tree
mortality. Mean tree stem growth measured over 20 years was lowest in the long unburnt treatment compared with the burn treatments,
although surface soil nutrient levels were generally higher in the unburnt treatment, suggesting these sites may be moisture
limited. There was no clear pattern of the effects of the burn treatments, including the number of fires and the interval
between fires, on tree stem growth, stand basal area increment, crown health or mortality. These factors were strongly influenced
by dominance condition, with dominant and co-dominant trees growing most and suppressed trees growing least and experiencing
the highest mortality levels. There was no evidence of deteriorating tree or stand health that could be attributed to either
regular low intensity burning or to a long period (25 years) of fire exclusion. 相似文献
972.
Resident Motivations and Willingness-to-Pay for Urban Biodiversity Conservation in Guangzhou (China)
The monetary assessment of biodiversity measures the welfare damages brought by biodiversity losses and the cost-benefit analysis
of conservation projects in a socio-economic context. The contingent valuation method could include motivational factors to
strengthen economic analysis of nature conservation. This study analyzed Guangzhou residents’ motivations and willingness-to-pay
(WTP) for an urban biodiversity conservation program in the National Baiyun Mountain Scenic Area (BMSA). The peri-urban natural
site, offering refuge to some endemic species, is under increasing development pressures for recreational and residential
use. A questionnaire survey was conducted in the Guangzhou metropolitan area during June to October 2007. We interviewed face-to-face
720 stratified sampled households to probe residents’ attitudes towards the city’s environmental issues, motivations for urban
nature conservation, and WTP for biodiversity conservation. Principal component analysis identified five motivational factors,
including environmental benefit, ecological diversity, nature-culture interaction, landscape-recreation function, and intergenerational
sustainability, which illustrated the general economic values of urban nature. Logistic regression was applied to predict
the probability of people being willing to pay for the urban biodiversity conservation in BMSA. The significant predictors
of WTP included household income and the factor nature-culture interaction. The median WTP estimated RMB149/household (about
US$19.5/household) per year and an aggregate of RMB291 million (approximately US$19.5/household) per year and an aggregate of RMB291 million (approximately US38.2 million) annually to support the urban
conservation project. Including public motivations into contingent valuation presents a promising approach to conduct cost-benefit
analysis of public projects in China. 相似文献
973.
People for the Ethical Treatment of Animals (PETA) called for a ban on mulesing in the Australian sheep industry in 2004.
Mulesing is a surgical procedure that removes wool-bearing skin from the tail and breech area of sheep in order to prevent
flystrike (cutaneous myiasis). Flystrike occurs when flies lay their eggs in soiled areas of wool on the sheep and can be
fatal for the sheep host. PETA claimed that mulesing subjects sheep to unnecessary pain and suffering and took action against
the Australian wool industry that resulted in a number of international clothing retailers choosing not to use Australian
wool. Although the Australian sheep industry agreed to phase out mulesing in 2010, there is some uncertainty as to whether
this deadline will be achieved. The changing social ethic towards animal welfare suggests that the way the Australian sheep
industry manages the phase out of mulesing in 2010 is vital to its future survival and success. It is likely that if mulesing
does not cease in 2010 there will be a negative market reaction to Australian wool and the risk of legislation to ban mulesing.
To avoid losing control of its animal welfare strategy, the Australian sheep industry should ensure that mulesing is phased
out in 2010 and endorse the animal welfare ethic underpinning this change. The industry should also educate farmers and other
industry stakeholders in how the changing social ethic for animal welfare can create new market opportunities for wool. 相似文献
974.
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
975.
976.
977.
By means of environmental education, teachers are supposed to intervene in pupils’ awareness and concern of environmental
issues. Teachers’ environmental attitudes, however, have rarely been studied. We analysed 367 German pre- and in-service teachers’
environmental attitudes for their structure and socio-economic correlates within the frame of a European project. Thus, we
retrieved for adults the two-dimensional model of ecological values (2-MEV) presented for adolescents by Bogner and Wiseman
(Sci Educ Int 15(1):27–48, 2004). For the two domains, Preservation and Utilisation, the psychometric structure was confirmed and discriminative correlations
with age, gender and teaching subject were unveiled. Further research is needed to deduce the implications for teaching practice. 相似文献
978.
979.
980.
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