A major characteristic of our global interactive climate-energy system is the large uncertainty that exists with respect to both future environmental requirements and the means available for fulfilling these. Potentially, a key technology for leading the transition from the current fossil fuel-dominated energy system to a more sustainable one is carbon dioxide capture and storage. Uncertainties exist, however, concerning the large-scale implementability of this technology, such as related to the regional availability of storage sites for the captured CO2. We analyze these uncertainties from an integrated assessment perspective by using the bottom-up model TIAM-ECN and by studying a set of scenarios that cover a range of different climate targets and technology futures. Our study consists of two main approaches: (1) a sensitivity analysis through the investigation of a number of scenarios under perfect foresight decision making and (2) a stochastic programming exercise that allows for simultaneously considering a set of potential future states-of-the-world. We find that, if a stringent climate (forcing) target is a possibility, it dominates the solution: if deep CO2 emission reductions are not started as soon as possible, the target may become unreachable. Attaining a stringent climate target comes in any case at a disproportionally high price, which indicates that adaptation measures or climate damages might be preferable to the high mitigation costs such a target implies. 相似文献
Ecofriendly fully bio-composites based on polyamide 11 (PA11) and lignin have been prepared on the entire concentration range using a twin-screw extruder. In this work, PA11 was blended with lignin by direct extrusion technology without any chemical pre- or in-situ- modifications or physical pretreatments. The presence of various organic and inorganic impurities in the selected technical lignin have been maintained. The incorporation of this cheap renewable material from biomass in bio-based PA11 was inspected by an array of characterization tools. Also, the effect of the presence of lignin on the morphology and on the mechanical properties of the resulting materials was examined. Finally, in-situ investigation of structural evolution in PA11 induced by the presence of lignin was analyzed by Fast Scanning Chip Calorimetry. 相似文献
Three-year-old Douglas firs (Pseudotsuga menziesii) were fumigated with 180 microg m(-3) NH3 or clean (charcoal-filtered) air. During these fumigations the plants received 15 mm artificial rain weekly, supplemented with 20, 500 or 2500 micromol litre(-1) (NH4)2SO4. Exposure to NH3 and NH4+ for 14 weeks resulted in a change of the nutrient status of the needles. The most remarkable effect was the increase in the N/K ratio, due to both uptake of N and leaching of K. The action of NH3 was stronger than that of NH4+. Both NH3 and (NH4)2SO4 affected the epicuticular wax layer and decreased mycorhiza frequency. Following fumigation and artificial rain treatments, needles were incubated for 8 h in a medium containing 0, 50, 250, 500 and 2500 micromol litre(-1) (NH4)2SO4. Almost no exchange of Ca, Mg and K for NH4+ was found. Therefore this ion exchange probably explains only a minor part of the changes in nutrient status of the whole trees. 相似文献
Objective: Our study measured the change in head injuries and deaths among motorcycle users in Cu Chi district, a suburban district of Ho Chi Minh City.
Methods: Hospital records for road traffic injuries (RTIs) were collected from the Cu Chi Trauma Centre and motorcycle-related death records were obtained from mortality registries in commune health offices. Head injury severity was categorized using the Abbreviated Injury Score (AIS). Rate ratios (RRs) were used to compare rates pre- and post-law (2005/2006–2009/2010). Cu Chi's population, stratified by year, age, and sex, was used as the denominator.
Results: Of records identifying the transportation mode at the time of injury, motorcyclists accounted for most injuries (3,035, 87%) and deaths (238, 90%). Head injuries accounted for 70% of motorcycle-related hospitalizations. Helmet use was not recorded in any death records and not in 97% of medical records. Males accounted for most injuries (73%) and deaths (88%). The median age was 28 years and 32 years for injuries and deaths, respectively. Compared to the pre-law period, rates of motorcycle injuries (RR = 0.53; 95% confidence interval [CI], 0.49–0.58), head injuries (RR = 0.35; 95% CI, 0.31–0.39), severe head injuries (RR = 0.47; 95% CI, 0.34–0.63), and deaths (RR = 0.69; 95% CI, 0.53–0.89) significantly decreased in the post-law period.
Conclusions: Rates of head injuries and deaths among motorcycle riders decreased significantly after implementation of the mandatory helmet law in Vietnam. To further examine the impact of the motorcycle helmet law, including compliance and helmet quality, further emphasis should be placed on gathering helmet use data from injured motorcyclists. 相似文献
Explorations of future land use change are important to understand potential conflicts between competing land uses, trade-offs associated with particular land change trajectories, and the effectiveness of policies to steer land systems into desirable states. Most model-based explorations and scenario studies focused on conversions in broad land use classes, but disregarded changes in land management or focused on individual sectors only. Using the European Union (EU) as a case study, we developed an approach to identifying typical combinations of land cover and management changes by combining the results of multimodel simulations in the agriculture and forest sectors for four scenarios from 2000 to 2040. We visualized land change trajectories by mapping regional hotspots of change. Land change trajectories differed in extent and spatial pattern across the EU and among scenarios, indicating trajectory-specific option spaces for alternative land system outcomes. In spite of the large variation in the area of change, similar hotspots of land change were observed among the scenarios. All scenarios indicate a stronger polarization of land use in Europe, with a loss of multifunctional landscapes. We analyzed locations subject to change by comparing location characteristics associated with certain land change trajectories. Results indicate differences in the location conditions of different land change trajectories, with diverging impacts on ecosystem service provisioning. Policy and planning for future land use needs to account for the spatial variation of land change trajectories to achieve both overarching and location-specific targets.
The contamination characteristics of arsenic and other trace elements in groundwater and the potential risks of arsenic from the groundwater were investigated. Elevated contamination of arsenic, barium and manganese was observed in tube-well water of two villages (Chuyen Ngoai and Chau Giang) in Ha Nam province in the Northern Vietnam. Concentrations of As in the groundwater ranged from 12.8 to 884 µg/L with mean values in Chuyen Ngoai and Chau Giang were 614.7 and 160.1 µg/L, respectively. About 83 % of these samples contained As concentrations exceeding WHO drinking water guideline of 10 μg/L. The mean values of Mn and Ba in groundwater from Chuyen Ngoai and Chau Giang were 300 and 657 μg/L and 650 and 468 μg/L, respectively. The mean value of Ba concentration in groundwater in both Chuyen Ngoai and Chau Giang was about 22 % of the samples exceeded the WHO guideline (700 µg/L). Arsenic concentrations in human urine of residents from Chuyen Ngoai and Chau Giang were the range from 8.6 to 458 µg/L. The mean values of Mn and Ba in human urine of local people from Chuyen Ngoai were 46.9 and 62.8 μg/L, respectively, while those in people from Chau Giang were 25.9 and 45.9 μg/L, respectively. The average daily dose from ingesting arsenic for consuming both untreated and treated groundwater is from 0.02 to 11.5 and 0.003 to 1.6 μg/kg day, respectively. Approximately, 57 % of the families using treated groundwater and 64 % of the families using untreated groundwater could be affected by elevated arsenic exposure. 相似文献
Land systems are described based on various characteristics, including land cover composition and agricultural production. However, it is uncertain to what extent livestock, particularly monogastric livestock, determines land systems. We included monogastrics in a land system classification, and statistically analyzed the land cover composition and agricultural production of otherwise similar land systems with and without monogastric livestock. The results indicate that land systems with monogastrics are statistically different from their counterparts in the classification without monogastrics in terms of grassland area and crop yields, but are less different in terms of tree area, crop area, and ruminant livestock production. We then used a land systems map that includes monogastrics in the classification and a similar map that does not include monogastrics to project future changes in a novel manner that integrates livestock as a determinant of land systems. The results show that including monogastrics in otherwise similar projections yields less cropland intensification and more cropland expansion in several world regions, including Northern Africa and the Middle East. Other regions, such as Europe and Australia, were characterized by less decrease or more increase in tree area in the application with monogastrics, mainly due to the occurrence of open forests with monogastrics. This study prompts a call for improved characterization of land systems for land use and cover change (LUCC) assessments in order to better represent LUCC driven by monogastric livestock. 相似文献
Analysis of satellite-telemetry data mostly occurs long after it has been collected, due to the time and effort needed to collate and interpret such material. Delayed reporting reduces the usefulness of such data for nature conservation where timely information about animal movements is required. To counter this problem, we present a novel approach which combines automated analysis of satellite-telemetry data with rapid communication of insights derived from such data. A relatively simple algorithm (based on radial and angular velocity calculated from fixes) allowed instantaneous detection of excursions away from settlement areas and automated calculation of home ranges on the remaining data. Automating the detection of both excursions and home-range calculations enabled us to disseminate ecological insights from satellite-tag data instantaneously through a dedicated web portal. The automated analysis, interpretation, and communication of satellite-tag and other ecological data offer clear benefits to nature conservation research and practice. 相似文献
The availability of affordable ‘recreational’ camera traps has dramatically increased over the last decade. We present survey results which show that many conservation practitioners use cheaper ‘recreational’ units for research rather than more expensive ‘professional’ equipment. We present our perspective of using two popular models of ‘recreational’ camera trap for ecological field-based studies. The models used (for >2 years) presented us with a range of practical problems at all stages of their use including deployment, operation, and data management, which collectively crippled data collection and limited opportunities for quantification of key issues arising. Our experiences demonstrate that prospective users need to have a sufficient understanding of the limitations camera trap technology poses, dimensions we communicate here. While the merits of different camera traps will be study specific, the performance of more expensive ‘professional’ models may prove more cost-effective in the long-term when using camera traps for research. 相似文献