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61.
Greenhouse gas (GHG) emissions from post-consumer waste and wastewater are a small contributor (about 3%) to total global anthropogenic GHG emissions. Emissions for 2004-2005 totalled 1.4 Gt CO2-eq year(-1) relative to total emissions from all sectors of 49 Gt CO2-eq year(-1) [including carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and F-gases normalized according to their 100-year global warming potentials (GWP)]. The CH4 from landfills and wastewater collectively accounted for about 90% of waste sector emissions, or about 18% of global anthropogenic methane emissions (which were about 14% of the global total in 2004). Wastewater N2O and CO2 from the incineration of waste containing fossil carbon (plastics; synthetic textiles) are minor sources. Due to the wide range of mature technologies that can mitigate GHG emissions from waste and provide public health, environmental protection, and sustainable development co-benefits, existing waste management practices can provide effective mitigation of GHG emissions from this sector. Current mitigation technologies include landfill gas recovery, improved landfill practices, and engineered wastewater management. In addition, significant GHG generation is avoided through controlled composting, state-of-the-art incineration, and expanded sanitation coverage. Reduced waste generation and the exploitation of energy from waste (landfill gas, incineration, anaerobic digester biogas) produce an indirect reduction of GHG emissions through the conservation of raw materials, improved energy and resource efficiency, and fossil fuel avoidance. Flexible strategies and financial incentives can expand waste management options to achieve GHG mitigation goals; local technology decisions are influenced by a variety of factors such as waste quantity and characteristics, cost and financing issues, infrastructure requirements including available land area, collection and transport considerations, and regulatory constraints. Existing studies on mitigation potentials and costs for the waste sector tend to focus on landfill CH4 as the baseline. The commercial recovery of landfill CH4 as a source of renewable energy has been practised at full scale since 1975 and currently exceeds 105 Mt CO2-eq year(-1). Although landfill CH4 emissions from developed countries have been largely stabilized, emissions from developing countries are increasing as more controlled (anaerobic) landfilling practices are implemented; these emissions could be reduced by accelerating the introduction of engineered gas recovery, increasing rates of waste minimization and recycling, and implementing alternative waste management strategies provided they are affordable, effective, and sustainable. Aided by Kyoto mechanisms such as the Clean Development Mechanism (CDM) and Joint Implementation (JI), the total global economic mitigation potential for reducing waste sector emissions in 2030 is estimated to be > 1000 Mt CO2-eq (or 70% of estimated emissions) at costs below 100 US$ t(-1) CO2-eq year(-1). An estimated 20-30% of projected emissions for 2030 can be reduced at negative cost and 30-50% at costs < 20 US$ t(-) CO2-eq year(-1). As landfills produce CH4 for several decades, incineration and composting are complementary mitigation measures to landfill gas recovery in the short- to medium-term--at the present time, there are > 130 Mt waste year(-1) incinerated at more than 600 plants. Current uncertainties with respect to emissions and mitigation potentials could be reduced by more consistent national definitions, coordinated international data collection, standardized data analysis, field validation of models, and consistent application of life-cycle assessment tools inclusive of fossil fuel offsets.  相似文献   
62.
This paper describes the analyses of polychlorinated dibenzodioxins, dibenzofurans, and related compounds in diphenyl ether herbicides, CNP, NIP, and X-52. The levels of tetra-, penta-CDDs, and tetra-CDFs were about 150, 30, and 15 ppm, respectively in CNP formulations. NIP and X-52 contained lower chlorine alalogs. Isomer distribution of PCDDs in CNP agreed with an estimate from the reaction of chlorophenols. Freshwater fish samples heavily contaminated with CNP in the application season also contained 0.2 ppb of 1,3,6,8-tetra-CDD.  相似文献   
63.
K. Wada 《Marine Biology》1987,95(2):299-303
The burrow living ocypodid crab Ilyoplax pusillus (De Haan, 1835) sometimes plugs the burrow of neighbors situated from 1.0 to 8.3 cm away with surface mud, while the neighbor, termed the pluggee, is in the burrow. Most pluggers were large males, whereas pluggees were smaller than pluggers and had a sex ratio close to 1:1. After being plugged, most pluggees usually reemerged on the surface within 5 min, but occasionally took up to 77 min to do so. The plugger always foraged or performed waving displays around the burrow of the pluggee while the pluggee stayed inside the burrow. Although the activity site of the pluggee was originally directed toward the burrow of the plugger or the adjacent area, after reemergence its activity site was oriented toward another direction. From these observations, it is suggested that neighbor burrow-plugging is a behavior adopted mainly by large males as a means of maintaining the area of their surface activities against smaller neighbors. My observations were made from June 1984 to June 1985 at Fukuro River Estuary, central Japan.  相似文献   
64.
beta-Carboline-3-carboxylic acid methylamide (FG 7142), an anxiogenic agent has been found in cigarette smoke condensate, but not in the cigarette itself. When a cigarette, except its filter portion, was immersed in 20 ml of potassium phosphate buffer, pH 7.4, then heated at 60 degrees C for 2 days with or without presence of methylamine, FG 7142 was detected only in the mixture containing methylamine. Furthermore, when the mixtures of beta-carboline derivatives and various amounts of methylamine hydrochloride were heated at 60 degrees C for 5 days, FG 7142 was formed only in the mixtures containing methylamine and 1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-caroxylic acid (MTCA) or 1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (TCCA). FG 7142 was also produced in the mixture of glucose, l-tryptophan and methylamine when heated at 200 degrees C in a dry condition. These observations suggest that FG 7142 is formed through the smoking process and that methylamine in cigarette smoke may play an important role in the formation of FG 7142.  相似文献   
65.
66.
Using NOAA AVHRR data to assess flood damage in China   总被引:2,自引:0,他引:2  
The article used two NOAA-14 Advanced Very High ResolutionRadiometer (AVHRR) datasets to assess flood damage in the middleand lower reaches of China's Changjiang River (Yangtze River) in 1998. As the AVHRR is an optical sensor, it cannot penetratethe clouds that frequently cover the land during the flood season, and this technology is greatly limited in flood monitoring. However the widely used normalized difference vegetation index (NDVI) can be used to monitor flooding, sincewater has a much lower NDVI value than other surface features.Though many factors other than flooding (e.g. atmospheric conditions, different sun-target-satellite angles, and cloud) can change NDVI values, inundated areas can be distinguished fromother types of ground cover by changes in the NDVI value beforeand after the flood after eliminating the effects of other factors on NDVI. AVHRR data from 26 May and 22 August, 1998 wereselected to represent the ground conditions before and after flooding. After accurate geometric correction by collecting GCPs,and atmospheric and angular corrections by using the 6S code, NDVI values for both days and their differences were calculatedfor cloud-free pixels. The difference in the NDVI values betweenthese two times, together with the NDVI values and a land-use map, were used to identify inundated areas and to assess the arealost to the flood. The results show a total of 358 867 ha, with 207 556 ha of cultivated fields (paddy and non-irrigated field) inundated during the flood of 1998 in the middle and lower reaches of the Changjiang River Catchment; comparing with the reported total of 321 000 and 197 000 ha, respectively. The discrimination accuracy of this method was tested by comparing the results from two nearly simultaneous sets of remote-sensingdata (NOAA's AVHRR data from 10 September, 1998, and JERS-1 synthetic aperture radar (SAR) data from 11 September, 1998, with a lag of about 18.5 hr) over a representative flooded regionin the study area. The results showed that 67.26% of the total area identified as inundated using the NOAA data was also identified as inundated using the SAR data.  相似文献   
67.
To analyze the motivations of Japanese companies to take environmental actions to reduce their greenhouse gas (GHG) emissions, we used FY2006 research data and questioned Japanese industries regarding their reduction of GHG emissions. Empirical investigations revealed that voluntary targets set by industry organizations, government requirements, and advance responses to possible future regulations can positively influence environmental actions for GHG emission reduction; however, cost reductions and corporate social responsibility fulfillment cannot.
Seiji IkkataiEmail:
  相似文献   
68.
Genetic population structures along the Japanese coast, analyzed by sequence data from the mitochondrial DNA COI region, were determined for four intertidal brachyuran species in the superfamily Thoracotremata (Ocypode ceratophthalma, Gaetice depressus, Chiromantes dehaani and Deiratonotus japonicus), which were characterized by different habitat requirements. O. ceratophthalma (seashore; supratidal sand) and C. dehaani (estuarine; supratidal marsh) showed no significant genetic differentiation among Japanese populations. The Japanese populations of O. ceratophthalma, however, were found to genetically differentiated from the Philippine population. G. depressus (seashore; intertidal cobbles) exhibited significant genetic differentiation between the Amami-Ohshima population and other local populations. D. japonicus (estuarine; intertidal cobbles) showed significant genetic differentiation among many local populations separated by about 30–1,200 km. The different patterns of genetic population structure recorded for the four species, thus, do not simply correspond to habitat type.  相似文献   
69.
This paper describes, compares and evaluates selected Oxidant Prediction Relationships {OPRs) in terms of projections of hydrocarbon emission reductions required for attainment of the former 0.08 ppm standard and the new 0.12 ppm standard in the San Francisco Bay Area in 1985. The OPRs analyzed are the LIRAQ physicochemical model, EPA’s Empirical Kinetic Modeling Approach (EKMA), linear and Appendix J rollback, and an empirical OPR based on local observations.

LIRAQ simulations indicated that to achieve the 0.12 ppm ozone standard, 1985 hydrocarbon emissions must be reduced by 27% from projected levels. The equivalent reductions derived from simple linear rollback, linear rollback with 0.04 ppm background, and the local empirical OPR were 32%, 45% and 37%, respectively. The LIRAQ simulations also showed that reduction of both hydrocarbon and NOx emissions is less effective than reduction of hydrocarbons only. The attempt to apply EKMA failed because the Bay Area’s low hydrocarbon/NOx ratios and observed ozone levels are not consistent with the standard EKMA isopleth curves.

For planning, proper OPR selection is important because the wide range in the projections of various OPRs translates into a correspondingly wide range in control costs. Physicochemical OPRs are preferred because they are verifiable; they account for complex topography, meteorology, and source distributions; and because they can treat a variety of control strategies. In the future, the uncertainties associated with the projections can be resolved by assessing trends in air quality on a regular basis and by upgrading and reapplying the prediction methodologies as new information becomes available.  相似文献   
70.
Juveniles of Leiognathus nuchalis were raised from fertilized eggs for up to 60 d and examined for luminescence activity. Almost all juveniles raised separately from adults failed to produce detectable light. In contrast, a significant percentage (33 to 100%) of the juveniles became luminescent in less than 48 h when they were either kept with adults or inoculated with a homogenate of the adult light organs. The luminescence tended to increase with time after the treatments. These findings suggest that: (1) most of L. nuchalis offspring typically hatch and develop apo-symbiotically and (2) at least 45 d after hatching, juveniles can be infected with symbiotic luminous bacteria from the light organ of adult fish, and thereby gain the ability to produce light. Received: 16 February 1999 / Accepted: 21 September 1999  相似文献   
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