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131.
Waste to energy conversion is based on the classification of waste. In-flight catering wastes resulting from Egypt Airlines economy class passengers were classified. The solid waste stream generated contains plastic, paper, left-over waste food and aluminum. The type of meal served varies according to the period of flight and so the quantity and content of the waste stream. It was found that the waste generation rate varied from 61.3 to 265 g according to the meal type. Breakfast snack meal generates the highest weight of waste which recorded an average of 265 g. Plastic waste generated varied from 39.6% to 64.6% by weight for the various types of meals served. A total amount of 725 tons were generated annually from organic waste (paper, plastic and food waste) among which a non combustible 39.4 tons of aluminum. The calorific value for each generated item is calculated and the total energy potential reached up to 14.3 TJ annually. 相似文献
132.
Jörg Luster Manoj Menon Sandra Hermle Rainer Schulin Madeleine S. Günthardt-Goerg Bernd Nowack 《Water, Air, & Soil Pollution: Focus》2008,8(2):163-176
Soil translocation for recultivation of soil removed from construction sites and for the preparation of refilled lysimeters
inevitably involves disturbance of soil structure, and, if intermediate storage is included, also drying and rewetting of
the soil. We report on an experiment with model forest ecosystems, where uncontaminated forest subsoils were covered with
non-contaminated or freshly heavy metal (mainly Zn and Cu) contaminated topsoil in large lysimeters. Monitoring of the chemical
composition of the drainage water revealed two distinct soil conditioning phases. During an initial phase of about a year
strongly elevated nitrate and sulfate concentrations occurred that were attributed to a mineralisation flush caused by the
increased accessability of mineralisable nitrogen and sulfur in destroyed aggregates. These effects were significantly larger
in lysimeters with calcareous subsoil than in those with acidic subsoil. The second phase was characterised by a gradual decrease
in dissolved organic carbon and sulfate concentrations, in particular in the acidic subsoil. This decrease may be attributed
to the depletion of pools made accessible during aggregate destruction or the formation of new aggregates. These chemical
changes had only little effects on the concentrations of copper and zinc in the drainage water. Based on our results, it can
be concluded that large refilled lysimeters can be used for many purposes without risk of compromised results, if a conditioning
phase of about 1 year with sufficiently moist soil conditions is respected. Nevertheless, gradual changes in soil chemical
characteristics still occur after this initial phase. Implications for the recultivation of sites using relocated soils are
discussed. 相似文献
133.
J. Gupta E. Bergsma C. J. A. M. Termeer G. R. Biesbroek M. van den Brink P. Jong J. E. M. Klostermann S. Meijerink S. Nooteboom 《Mitigation and Adaptation Strategies for Global Change》2016,21(6):883-903
The climate change problem calls for a continuously responding society. This raises the question: Do our institutions allow and encourage society to continuously adapt to climate change? This paper uses the Adaptive Capacity Wheel (ACW) to assess the adaptive capacity of formal and informal institutions in four sectors in the Netherlands: spatial planning, water, agriculture and nature. Formal institutions are examined through an assessment of 11 key policy documents and informal institutions are analysed through four case studies covering each sector. Based on these ACW analyses, both sector-specific and more general strengths and weaknesses of the adaptive capacity of institutions in the Netherlands are identified. The paper concludes that the most important challenge for increasing institutional adaptive capacity lies in combining decentralized, participatory approaches with more top-down methods that generate leadership (visions, goals) standards, instruments, resources and monitoring. 相似文献
134.
We conducted case studies of three successful examples of collaborative, community-based natural resource conservation and development. Our purpose was to: (1) identify the functions served by interactions within the social networks of involved stakeholders; (2) describe key structural properties of these social networks; and (3) determine how these structural properties varied when the networks were serving different functions. The case studies relied on semi-structured, in-depth interviews of 8 to 11 key stakeholders at each site who had played a significant role in the collaborative projects. Interview questions focused on the roles played by key stakeholders and the functions of interactions between them. Interactions allowed the exchange of ideas, provided access to funding, and enabled some stakeholders to influence others. The exchange of ideas involved the largest number of stakeholders, the highest percentage of local stakeholders, and the highest density of interactions. Our findings demonstrated the value of tailoring strategies for involving stakeholders to meet different needs during a collaborative, community-based natural resource management project. Widespread involvement of local stakeholders may be most appropriate when ideas for a project are being developed. During efforts to exert influence to secure project approvals or funding, however, involving specific individuals with political connections or influence on possible sources of funds may be critical. Our findings are consistent with past work that has postulated that social networks may require specific characteristics to meet different needs in community-based environmental management. 相似文献
135.
Mart-Jan Schelhaas Geerten Hengeveld Marco Moriondo Gert Jan Reinds Zbigniew W. Kundzewicz Herbert ter Maat Marco Bindi 《Mitigation and Adaptation Strategies for Global Change》2010,15(7):681-701
Risks can generally be described as the combination of hazard, exposure and vulnerability. Using this framework, we evaluated
the historical and future development of risk of fire and wind damage in European forestry at the national level. Fire risk
is expected to increase, mainly as a consequence of an increase in fire hazard, defined as the Fire Weather Index in summer.
Exposure, defined as forest area, is expected to increase slightly as a consequence of active afforestation and abandonment
of marginal agricultural areas. Adaptation options to fire risk should therefore aim to decrease the vulnerability, where
a change in tree species from conifers to broadleaves had most effect. Risk for wind damage in forests is expected to increase
mainly as a consequence of increase in exposure (total growing stock) and vulnerability (defined by age class and tree species
distribution). Projections of future wind climate indicate an increase in hazard (storminess) mainly over Western Europe.
Adaptation options should aim to limit the increase in exposure and vulnerability. Only an increase in harvest level can stop
the current build-up of growing stock, while at the same time it will lower vulnerability through the reduction of the share
of old and vulnerable stands. Changing species from conifers to broadleaves helps to reduce vulnerability as well. Lowering
vulnerability by decreasing the rotation length is only effective in combination with a high demand for wood. Due to data
limitations, no forecast of future fire area or damaged timber amount by storms was possible. 相似文献
136.
The capability of a cost-effective and a small size decentralized pilot wastewater treatment plant (WWTP) to remove enteric viruses such as rotavirus, norovirus genogroup I (GGI), norovirus genogroup II (GGII), Hepatitis E virus (HEV), and adenovirus was studied. This pilot plant is an integrated hybrid anaerobic/aerobic setup which consisted of anaerobic sludge blanket (UASB), biological aerated filter (BAF), and inclined plate settler (IPS). Both the UASB and BAF are packed with a non-woven polyester fabric (NWPF). Results indicated that the overall log10 reductions of enteric viruses’ genome copies through the whole system were 3.1 ± 1, 3.3 ± 0.5, and 2.6 ± 0.9 log10 for rotavirus, norovirus GGI, and adenovirus, respectively. Reduction efficiency for both norovirus GGII and HEV after the different treatment steps could not be calculated because there were no significant numbers of positive samples for both viruses. The overall reduction of rotavirus infectious units through the whole system was 2.2 ± 0.8 log10 reduction which is very close to the overall log10 reduction of adenovirus infectious units through the whole system which was 2.1 ± 0.8 log10 reduction. There was no considerable difference in the removal efficiency for different rotavirus G and P types. Adenovirus 41 was the only type detected in the all positive samples. Although the pilot WWTP investigated is cost effective, has a small footprint, does not need a long distance network pipes, and easy to operate, its efficiency to remove enteric viruses is comparable with the conventional centralized WWTPs. 相似文献
137.
Scott W. Stine Inhong Song Christopher Y. Choi Charles P. Gerba 《Food and environmental virology》2011,3(2):86-91
The purpose of this study was to quantify the transfer of viral and bacterial pathogens in water used to dilute pesticides
sprayed onto the surfaces of cantaloupe, iceberg lettuce, and bell peppers. The average percent transfer of bacteria was estimated
to range from 0.00021 to 9.4%, while average viral transfer ranged from 0.055 to 4.2%, depending on the type of produce. Based
on these values the concentrations of hepatitis A virus (HAV) and Salmonella in water necessary to achieve a 1:10,000 annual risk of infection were calculated. Under worst case scenario assumptions,
in which a pesticide is applied on the same day that the produce is harvested and when maximum transfer values are used, concentrations
of 1.5 × 10−3 CFU Salmonella or 2.7 × 10−7 MPN HAV per 100 ml of the water used for application would result in 1:10,000 annual infection risk to anyone who consumes
the fresh produce. If harvesting does not occur until at least 14 days after the application, to produce the same risk of
infection, the numbers of Salmonella in 100 ml of water used to dilute the pesticides will be greater by up to five orders of magnitude, while the HAV numbers
will have increased by up to two orders of magnitude. Based on the reported concentrations of enteric viruses in surface and
ground waters in the United States, a 1:10,000 annual risk of infection could easily be exceeded with some groundwater sources
used in the United States. To reduce the risks associated with the consumption of fresh produce, water used to prepare pesticides
in spray applications should be evaluated for its microbiological quality. 相似文献
138.
This is the first report of gynandromorphy in Isoptera. An Asian dry-wood termite, Neotermes koshunensis (Shiraki) [Kalotermitidae], possessing both male and female phenotypic characteristics, was found on Okinawa Island, Japan. This deformed individual showed morphological and anatomical hermaphroditism in the abdomen. The right side of the seventh sternite was the female form and contained an ovary, while the left side was the male form and contained a testis. Genotypic analysis revealed that this individual was a genotypic bilateral chimera. These results suggested that the termite was a bilateral gynandromorph with a male left side and a female right side. As reported previously in other insects, double fertilization (by two sperms, one with an X and one with a Y chromosome) of a binucleate egg is the most likely mechanism that generated this genotypic bilateral chimera. N. koshunensis has the ability to reproduce through parthenogenesis, in which the secondary polar body is likely to be used for nuclear phase recovery. If the second polar body in this mechanism has high fertility and healthy embryogenic potential, like an egg nucleus, some of gynandromorphs might be produced by a side effect of parthenogenetic ability. 相似文献
139.
Katherine Comer Santos Marielle Livesey Marianne Fish Armando Camargo Lorences 《Mitigation and Adaptation Strategies for Global Change》2017,22(1):121-135
Sandy beach habitat where sea turtles nest will be affected by multiple climate change impacts. Before these impacts occur, knowledge of how nest site selection and hatching success vary with beach microhabitats is needed to inform managers on how to protect suitable habitats and prepare for scientifically valid mitigation measures at beaches around the world. At a highly successful green turtle (Chelonia mydas) rookery at Akumal, Quintana Roo, Mexico, we measured microhabitat characteristics along the beach crawl (rejected sites) and related nest site conditions (selected sites) to subsequent hatching success rates for 64 nesting events. To our knowledge, this is the first study to report environmental data along the nesting crawl for a green turtle population and the first to use natural breaks in the data to describe their preferred habitat ranges. Our results indicate that turtles were likely using a combination of cues to find nest sites, mainly higher elevations and lower sand surface temperatures (Kruskal-Wallis test, H?=?19.84, p?<?0.001; H?=?10.78, p?<?0.001). Hatching success was significantly and negatively correlated to sand temperature at cloaca depth (Spearman’s ρ?=??0.27, p?=?0.04). Indeed, the preferred range for cloaca sand temperatures at the nest site (26.3–27.5 °C) had significantly higher hatching success rates compared to the highest temperature range (Tukey HSD?=?0.47, p?=?0.05). Sand temperatures at various depths were intercorrelated, and surface and cloaca depth sand temperatures were correlated to air temperature (ρ?=?0.70, p?=?0.00; ρ?=?0.26, p?=?0.04). Therefore, rising air temperatures could alter sand temperature cues for suitable nest sites, preferred nest site ranges, and produce uneven sex ratios or lethal incubating temperatures. Elevation cues and preferred ranges (1.4–2.5 m) may also be affected by sea level rise, risking inundation of nests. 相似文献
140.
Perceiving the Environment from the Lay Perspective in Desertified Areas,Northern China 总被引:1,自引:0,他引:1
Investigating local people’s environmental perceptions can produce useful information that could be incorporated into decision
making processes that help resolve environmental problems. Although China is undergoing severe desertification, the perceptions
of the local people toward their degraded environment and the related issues have so far not been actively solicited. This
article, which is a supplement to Lee and Zhang’s (2004, 2005) studies, seeks to further investigate the lay public’s general environmental attitudes, perceptions of desertification, interpretations
of land-degrading activities, and particularly their interrelations in severely desertified areas. Minqin County in Gansu
Province, northern China, was chosen to be the study area. Data was collected via a questionnaire survey (n = 1138) administered in December 2002. Major findings were: (1) Most respondents had only weak altruistic environmental attitudes,
with educational level to be a significant determinant. (2) Respondents’ perceptions of desertification and interpretations
of land-degrading activities were contingent on personal attributes, general environmental attitudes, and other conceptions
related to desertification. It is recommended that the interrelations between the various aspects of the public’s environmental
perceptions should be thoroughly examined to facilitate their participation in environmental management. 相似文献