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101.
Organochlorines are highly hydrophobic, synthetic organic pollutants that accumulate in the environment and in food webs. The primary route of human exposure to organochlorines is through food-mainly fat-rich food of animal origin such as meat, fish, and dairy products. Here we determined the presence and concentration of organochlorine residues in pasteurized milk from Mato Grosso do Sul, Brazil, to monitor consumer exposure to these contaminants. Organochlorine pesticides in milk samples were analyzed using solid phase extraction in octadecyl silica-prepacked columns and identified by gas chromatography using an electron capture detector. Of the 100 composite samples analyzed, more than 90% contained residues of organochlorine pesticides: aldrin was present in 44% of the samples, followed by ∑DDT (36%), mirex (34%), endosulfan (32%), chlordane (17%), dicofol (14%), heptachlor (11%) and dieldrin (11%). Compared to the values established by law, the concentration of the compounds in some samples was above the reference values. Given the importance that milk and its products have in the human diet, it is essential to know whether the levels of pesticide residues are kept well below the recommended levels to minimize the risk to human health.  相似文献   
102.
Water resources in Australia are sensitive to changes in rainfall. Ongoing droughts in south-west and south-east Australia are stressing water resources in the major cities and in agricultural regions. Climate change scenarios for Australia include reasonable prospects of long-term drying, which would exacerbate these issues. The dryer scenarios would entail major readjustments and costs on natural and human systems.  相似文献   
103.
Climate adaptation is a complex task surrounded by uncertainty. To support climate adaptation policies, a new scenario approach is pursued to explore possible discontinuous future developments of societal perspectives on climate adaptation issues. The scenario approach was tested for a case study on Dutch river management. In a series of scenario development workshops, a select group of stakeholders explored the perspectives on the management of the River Meuse in the past, present, and future. The process was supported by an analytical perspectives mapping tool to illustrate and analyze the development of perspectives over time. The process and analytical tools contributed to insight into the drivers of perspective change for the case study at hand. Moreover, the stakeholders highlighted the potential of the approach for water management policy for creating awareness about the plurality of perspectives and the dynamics of perspective change, monitoring perspectives and perspective change as part of a flexible policy approach, and anticipating on the occurrence of shock events. Further work is required to better represent the social dynamics of perspectives change, to better empirically ground the perspective change model, and to apply integrated water models in the scenario development process to assess water–society interactions.  相似文献   
104.
Anthropogenic biomass burning in insular Southeast Asia facilitates conversion and degradation of ecosystems and emits high amounts of carbon into the atmosphere. We analyzed the influence of peat soil and land cover distribution on the occurrence and characteristics of vegetation fires. Two years of satellite-based active fire detections over Peninsular Malaysia, Sumatra, Borneo and Java were examined together with land cover and peatland maps. Our results showed that fire occurrence nearly tripled (23,000 → 68,000) from a wet La Niña year (2008) to a drier El Niño year (2009). In both years, fires were concentrated in peatlands (in 2009 41% of fires vs. 10% of land area), and the majority of large-scale burning took place in peatlands. Variation in peatland land cover within the study area was noticed to create remarkable different fire regimes. Biomass burning in the intensely managed Sumatran peatlands was characterized by large-scale land clearance fires that took place annually to varying extent. The largely unmanaged degraded peatland ecosystems of Borneo, on the other hand, experienced very little fire activity in a wet year but were ravaged by large-scale wildfires when El Niño conditions arose. We conclude that fire regime characteristics in insular Southeast Asia are strongly connected to occurrence of peat soil and land management status. This leads to high variation of fire activity within this region both annually (depending on weather patters) and over longer time range (depending on land cover/management issues) and greatly complicates estimation of the effects of fires.  相似文献   
105.
Climate is one of the more complex physical systems in nature, its behaviour being fundamentally non-linear and chaotic. In assessing the potential risks from climate change and the costs of averting it, researchers and policymakers encounter pervasive uncertainty. Sceptics demand to get rid of the inherent uncertainties, and some experts, on the other end, keep sending out messages of catastrophic scenarios hoping that this will increase people’s awareness of the danger we face. The recent admission of a mistake in IPCC’s Climate change 2007 report (promptly broadcast by all the major media groups and newspapers from Jan. 20th 2010 onwards) made by the head of the Intergovernmental Panel on Climate Change—that Himalayan glaciers could melt away by 2035 (the IPCC claim of 2035 is wrong by over 300 years.)—has already brought a damage to the IPCC’s reputation that is likely to be considerable. But in this paper, perhaps risking being provocative and paradoxical, instead of looking for the right answers to what we think are inevitable uncertainties, we intend to search for new questions that may lead to a new way of thinking and may bring about new lifestyles and behaviour for citizens and firms.  相似文献   
106.
Addressing urban housing crisis is an enormous challenge for most of the countries due to the increasing cost of the building material. Therefore, affordable alternative building material can make a breakthrough to the urban housing crisis. In the light of current success of stabilised earth construction in urban low-cost housing, it is important to find out the potential drivers that can help to adopt this building material. This paper aims to identify and highlight these drivers from the method of literature review and validates through a Delphi technique.  相似文献   
107.
The developing countries i.e., the non-Annex-I countries (parties to the Kyoto Protocol but not responsible to any reduction target yet) in the Kyoto Protocol whose economies are in transition are also allowed to reduce GHG emissions. Among these, the countries that have accepted the Kyoto Protocol may be benefited from CDM projects to promote sustainable development. The developed countries i.e., the Annex-I countries (that have signed the Kyoto Protocol & are responsible to have specific GHG emission reduction target) or the investing countries, in return, have privilege to purchase CER credits (in units equivalent to one tonne of CO2 gas emission reduction) to meet the emission target as specified in the Kyoto Protocol. The key step in understanding about CDM is to grasp the concept of “baseline” and “additionality”. The “Baseline” is the emissions level that would have existed if a CDM project had not happened. The feature of an approved CDM project is that the planned reductions would not occur without the additional incentive provided by emission reduction credits; this concept is known as “Additionality”. According to environmental additionality concept, baseline emission minus project emission is equal to emissions reduction. “Investment Additionality,” ultimately rejected during negotiation of the “Marrakech Accords” and “Financial Additionality,” are the two important concepts. The concept of trading of CER matches to the idea of Pigovian tax (equal to the negative externality and which is considered one of the “traditional” means of bringing a modicum of market forces) in Economics, making pollution more costly to the polluter, as the polluters have negative cost since they save money by polluting; hence, there are supposed negative externalities associated with the market activity. Economic theory predicts that in an economy where the cost of reaching mutual agreement between parties is high and where pollution is diffuse, Pigovian tax will be an efficient way to promote the public interest and will lead to an improvement of the quality of life measured by the Genuine Progress Indicator and other human economic indicators, as well as higher gross domestic product growth. We can seek a level of pollution such that the marginal savings (MS) to one polluting unit from pollution (−MC) is equal to marginal damage (MD) from pollution over the entire population, since pollution is a public bad i.e., MS (x*) = ∑MDi (x*) where ∑Di (x) is the total damage. Though the responsibility of reduction in emission does not lie on the non-Annex-I countries, still effort of maintaining global emission balance can be expected equally from developed and developing countries. The responsibilities of Kyoto Protocol are (a) to reduce global GHG emissions, (b) to bring about sustainable development in the developing countries lie on above two groups since its effect on February 16, 2005. Different polluters have different costs of pollution control. The least costly way of controlling pollution from various sources that reflects different costs of pollution control making the set of environmental regulations to achieve the emission target at the lowest cost makes the regulation cost-effective. Though efficiency is not attainable for many regulations, cost-effectiveness is attainable.  相似文献   
108.
This study aims to estimate the intensification of rice farming in Myanmar particularly due to chemical fertilizer application, using farm-level data obtained from field surveys conducted in the 2000s. Relatively high-input rice farming was found in dry season crop in the delta zone and the double crop in well-irrigated lowlands of the central dry zone. The chemical fertilizer used there was about 88–159 kg NPK (nitrogen, N; phosphate, P2O5; and potash, K2O) ha−1 (76–110 kg nitrogen (N) ha−1), and the average paddy yield ranged from 2.8 to 3.5 ton ha−1. On the other hand, nutrient input in survey sites of rain-fed lowland was between 11 and 53 kg NPK ha−1 (5 and 36 kg N ha−1), and the yield ranged from 1.1 to 2.3 ton ha−1. The national average of paddy yield and nutrient input of fertilizer was roughly estimated to be around 2.4 ton ha−1 and 60 kg NPK ha−1, respectively. A gap was observed between these calculated values and the official statistics. A comparison of fertilizer use efficiency for rice production in Myanmar with that in China and Vietnam has shown that the efficiency in Myanmar has not declined to an inappropriate level even in its intensive ones. Rice production in Myanmar has room for increasing the yield by capital intensification. Nevertheless, considering its sustainability as well as productivity, further intensification in rice farming technology in irrigated lowlands of Myanmar may neither be the best nor the only way.  相似文献   
109.
The circular economy has been developing rapidly in recent years in China. A legislative system has been created to provide legal protection for the development of a circular economy, including a series of price and tax measures in the waste management area. These measures form the basic foundation for promoting better waste management under the circular economic model. Many challenges, however, remain. For instance, the legal system needs to incorporate more sophisticated science, and China lacks key waste treatment technology that could support the further development of a circular economy. There is also a need to educate the public about the concept of the circular economy and its benefits. Specific suggestions are made for the development and implementation of the circular economic model.  相似文献   
110.
Effective handling of municipal digested sludge requires that the product cake have low water content. To this end, we investigated the change in sludge dewaterability after the addition of fly ash to municipal digested sludge, dewatering of which is difficult because of its high organic content. The performance of the dewatering is compared with that of electroosmotic dewatering (EDW) and conventional mechanical dewatering (CMD). Fly ash classified by sieving to the size of 25–75 μm and >75 μm is added to the municipal digested sludge by 10, 20, and 50 wt% by wet base. When adding fly ash particles to municipal digested sludge, dewatering efficiency improved with smaller fly ash particle size and with increase in the amount. When sludge was dewatered using an electroosmotic dewatering method, the dewatering efficiency is improved about 40% by adding fly ash of 25–75 μm particle size with 20 wt% when compared with conventional mechanical dewatering method without adding the fly ash. It is concluded that fly ash particles rich in inorganic material are helpful in the dewatering process when added to municipal digested sludge and EDW is more effective than CDW.  相似文献   
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