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81.
82.
The European Union (EU) has advocated an emission reduction target for developed countries of 80% to 95% below the 1990 level by 2050, and a global reduction target of 50%. Developing countries have resisted the inclusion of these targets in both the UN Framework Convention on Climate Change Copenhagen Accord and Cancún Agreements. This paper analyses what these targets would imply for emission targets, abatement costs and energy consumption of developing countries, taking into account the conditional emission reduction pledges for 2020. An 80% reduction target for developed countries would imply more stringent per capita emission targets for developing countries than developed countries by 2050. Moreover, abatement costs of developing countries would be higher than those of developed countries. An 85% to 90% reduction target for developed countries would result in similar per capita emission targets and abatement costs for developed and developing countries by 2050. Total reduction targets for developing countries would range from 30% to 40% below 2005 levels by 2050 and from 30% to 35% above 2005 levels by 2030. The 2030 target for China would be 40% to 45% above 2005 levels, compared to a target for the EU of 45% to 50% below 1990 and for the United States of America (USA) 30% to 35% below 1990. Emission target trajectories for Brazil, South Africa and China would peak before 2025 and for India by around 2025. From the analysis, we may conclude that from the viewpoint of developing countries either developed countries increase their target above 85%, and/or make substantial side-payments.  相似文献   
83.
Guanabara Bay is a 384-km2 coastal bay with 70% of the population of the metropolitan area of Rio de Janeiro located within its drainage basin. The water quality of the Bay is impacted by domestic and industrial runoff, of which only 15% has been adequately treated. However, based on a 14-year monitoring program, the water quality for most of Guanabara Bay remains acceptable because of intense tidal flushing, and we failed to find a worsening of conditions during the 14-year study. The inner shallow regions of the Bay, the western and northwestern parts, receive most of the drainage from metropolitan Rio de Janeiro. It is here that the water quality is alarmingly poor, characterized by hypertrophic conditions and occasional hypoxic events. Fecal coliform counts in these inner reaches of the Bay are 4–100 times higher than the maximum acceptable count for recreational waters. Hypertrophic conditions prevail in Guanabara Bay, which is characterized by low dissolved oxygen, high biochemical oxygen demand, peaks in fecal coliform, and extremely high chlorophyll-a concentrations, which reflect high quantities of nutrients entering the system. These anthropogenic pressures are a threat to planktonic and benthic communities and are reminiscent of San Francisco Bay 30 years ago. The Guanabara Bay water quality could be returned to pre-1950 conditions, but it would require sufficient political will and economic investment to ensure that at least 80–90% of the domestic and industrial sewage were treated adequately. Electronic Publication  相似文献   
84.
85.
This study was undertaken to investigate the effects of sublethal concentration of three different classes of insecticides (carbamate, organophosphate, and pyrethroid compounds) on the freshwater fish Corydoras paleatus. For this purpose, fish were exposed for 96 hours to commercial pesticides. Different biomarkers were analyzed as levels of lipid peroxidation (LPO), piscine micronucleus test, and enzymatic activities of catalase (CAT), glutathione S-transferase (GST), and acetylcholinesterase (AChE). The brain AChE was inhibited with carbaryl and methyl parathion, but no inhibition was observed with deltamethrin. The insecticides did not cause oxidative stress or genotoxic effects at the tested concentrations. Further studies are needed to elucidate the biotransformation of Corydoras paleatus insecticides and a possible resistance mechanism.  相似文献   
86.
Effects of triclosan on zebrafish early-life stages and adults   总被引:1,自引:0,他引:1  

Background, aim and scope  

The biocide triclosan (TCS) is commonly used in personal care, acrylic, plastic, and textiles products. TCS has been detected in surface water in several countries, and its ecological impact is largely unknown. In this work, the toxicity of TCS in zebrafish (Danio rerio), embryos and adults was studied. Several lethal and sub-lethal endpoints were analysed in organisms exposed to TCS such as mortality, embryo development and behaviour, hatching, micronuclei and biochemical markers (cholinesterase (ChE), glutathione S-transferase (GST) and lactate dehydrogenase (LDH)).  相似文献   
87.
In the present study, selected advanced oxidation processes (AOPs)—namely, photo-Fenton (with Fe2+, Fe3+, and potassium ferrioxalate—FeOx—as iron sources), solar photo-Fenton, Fenton, and UV/H2O2—were investigated for degradation of the antineoplastic drug mitoxantrone (MTX), frequently used to treat metastatic breast cancer, skin cancer, and acute leukemia. The results showed that photo-Fenton processes employing Fe(III) and FeOx and the UV/H2O2 process were most efficient for mineralizing MTX, with 77, 82, and 90 % of total organic carbon removal, respectively. MTX probably forms a complex with Fe(III), as demonstrated by voltammetric and spectrophotometric measurements. Spectrophotometric titrations suggested that the complex has a 2:1 Fe3+:MTX stoichiometric ratio and a complexation constant (K) of 1.47 × 104 M–1, indicating high MTX affinity for Fe3+. Complexation partially inhibits the involvement of iron ions and hence the degradation of MTX during photo-Fenton. The UV/H2O2 process is usually slower than the photo-Fenton process, but, in this study, the UV/H2O2 process proved to be more efficient due to complexing of MTX with Fe(III). The drug exhibited no cytotoxicity against NIH/3T3 mouse embryonic fibroblast cells when oxidized by UV/H2O2 or by UV/H2O2/FeOx at the concentrations tested.  相似文献   
88.
We present a synoptic, participatory vulnerability assessment tool to help identify the likely impacts of climate change and human activity in coastal areas and begin discussions among stakeholders on the coping and adaptation measures necessary to minimize these impacts. Vulnerability assessment tools are most needed in the tropical Indo-Pacific, where burgeoning populations and inequitable economic growth place even greater burdens on natural resources and support ecosystems. The Integrated Coastal Sensitivity, Exposure, and Adaptive Capacity for Climate Change (I-C-SEA Change) tool is built around a series of scoring rubrics to guide non-specialists in assigning scores to the sensitivity and adaptive capacity components of vulnerability, particularly for coral reef, seagrass, and mangrove habitats, along with fisheries and coastal integrity. These scores are then weighed against threat or exposure to climate-related impacts such as marine flooding and erosion. The tool provides opportunities for learning by engaging more stakeholders in participatory planning and group decision-making. It also allows for information to be collated and processed during a “town-hall” meeting, facilitating further discussion, data validation, and even interactive scenario building.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0652-x) contains supplementary material, which is available to authorized users.  相似文献   
89.
Summary. We investigated the volatile emissions of Manchurian ash seedlings, Fraxinus mandshurica, in response to feeding by the emerald ash borer, Agrilus planipennis, and to exogenous application of methyl jasmonate (MeJA). Feeding damage by adult A. planipennis and MeJA treatment increased volatile emissions compared to unexposed controls. Although the same compounds were emitted from plants damaged by beetles and treated with MeJA, quantitative differences were found in the amounts of emissions for individual compounds. Adult virgin female A. planipennis were similarly attracted to volatiles from plants damaged by beetles and those treated with MeJA in olfactometer bioassays; males did not respond significantly to the same volatiles. Coupled gas chromatographic-electroantennogram detection (GC-EAD) revealed at least 16 antennally-active compounds from F. mandshurica, including: hexanal, (E)-2-hexenal, (Z)-3-hexen-1-ol, 3-methyl-butylaldoxime, 2-methyl-butylaldoxime, (Z)-3-hexen-1-yl acetate, hexyl acetate, (E)-β-ocimene, linalool, 4,8-dimethyl-1,3,7-nonatriene, and E,E-α-farnesene. Electroantennogram (EAG) dose–response curves using synthetic compounds revealed that females had a stronger EAG response to linalool than males; and male responses were greater to: hexanal, (E)-2-hexenal, (Z)-3-hexen-1-ol, 3-methyl-butylaldoxime, 2-methyl-butylaldoxime, and hexyl acetate. These results suggest that females may use induced volatiles in long-range host finding, while their role for males is unclear. If attraction of females to these volatiles in an olfactometer is upheld by field experiments, host plant volatiles may find practical application in detection and monitoring of A. planipennis populations.  相似文献   
90.
The aim of this study was to determine the feasibility of karyotyping ectopic Fallopian tube pregnancies utilizing dividing cytotrophoblast cells. Villi from 78 ectopic conceptuses were processed by the direct chromosome technique and cytogenetic diagnosis was successful in 60 cases (76-9 per cent). The amount of villi obtained, as well as villus morphology, was correlated with cytogenetic success rate. Histological examination of the Fallopian tube was also carried out. A total of 47 cases were chromosomally abnormal (78-3 per cent), which is the highest frequency of cytogenetic abnormalities reported to date.  相似文献   
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