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111.
RaMCo is a prototype version of a decision-support system for coastal-zone management. The model is based on the findings of a multidisiciplinary research program, conducted in Southwest Sulawesi, Indonesia. Different management strategies can be compared on the basis of the short- and long-term consequences. Land-use change has been included in RaMCo in view of the impacts of land-based human activities on the marine environment. The key aspect of the model is a combination of the temporal dynamics of land-use change on the regional (macro-level) scale and spatial dynamics on the local (micro-level) scale. Constrained cellular automata are used to integrate both scale levels. The state changes of the cells depend on the consistency with the macro-scale model, local geographical conditions, and interaction with neighboring cells. In this paper, we discuss the underlying theoretical assumptions of the macro-scale and micro-scale models, some characteristic results for land-use change in the study area, and the validation problem.  相似文献   
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Eye development, optical properties and photomechanical responses were examined in embryos and hatchlings of the southern calamary, Sepioteuthis australis. This species occurs in shallow coastal waters in Australia and New Zealand, and the egg masses were collected in October and December 2004 from Great Oyster Bay, Tasmania. At the earliest developmental stage the eye of the squid was comprised of a hemispherical cup of undifferentiated neural retina, while presumptive iris cell layers and lentigenic precursor cells enclosed a posterior eye chamber. Differentiation of the proximal and distal processes was observed in correspondence with the cornea development and lens crystallization, and occurred before differentiation of the neural retina, which was complete prior to hatching. Longer photoreceptor distal processes were first observed just prior to hatching in the dorsal-posterior retina. After hatching, this difference was much more evident and higher photoreceptor density was found in the central retina. This indicates that the eye of S. australis at this age uses different retina areas for different visual tasks. Optical sensitivity and resolution suggest that juvenile S. australis are diurnal. This study also found functional photomechanical responses of visual screening pigment migration and pupil constriction in S. australis embryos, although complete functionality of the pupil at this stage was uncertain. However, the pupils of squid aged 2 days closed almost completely under bright conditions, showing that photomechanical responses were highly developed in the juvenile squid. These findings indicate that squid embryos are able to perceive visual stimulation, suggesting an early reliance on vision for survival after hatching.  相似文献   
114.
The rollback or proportional model is widely used in pollution control calculations and included in the guidelines for preparing and evaluating state implementation plans. Its basis and limitations are not widely known or understood. In this paper, the basis and limitations of rollback are listed and discussed, and extensions of basic rollback are proposed.  相似文献   
115.
ABSTRACT

The large share of carbon emitted by energy-intensive industries in the extraction and processing of basic materials must be limited to decarbonise society and the economy. Ways in which the state can govern industrial decarbonisation and contributes to green state theory are explored by addressing a largely ignored issue: the green state’s industrial relations and its role in industrial governance. With insights from a Swedish case study, the tension between the state’s economic imperative and ecological concerns in greening industry are shown to persist. However, as the energy-intensive industry’s previously privileged position in the economy is weakening, industry is opened to decarbonisation strategies. While the case exposes a number of governance challenges, it also suggests potential areas where the state can pursue decarbonisation in energy-intensive industry and points the way to an active role of the green state in governing industrial decarbonisation and greening industry.  相似文献   
116.
Abstract

This paper summarizes the sampling and analytical methods developed to identify and measure polycyclic aromatic hydrocarbons (PAH) and related aromatic compounds near a Horizontal Stud Soderberg plant at Jonquiere, Quebec, Canada. The primary source of PAH is the coal tar pitch used as a binder in Soderberg anodes. Twice a week at a number of sampling sites, airborne particulate matter was collected on glass-fiber filters using a Hi-Vol sampler for a twenty-four hour period. Organics on the filter were Soxhlet extracted with benzene.

Identification was done by gas chromatography-mass spectrometry (GC-MS). The vast majority of compounds present were PAH, but small amounts of alkyl PAH and polycyclic aromatic compounds with heteroatoms such as nitrogen, oxygen and sulfur were also identified. Based on the GC-MS identification, a group of 14 PAH was selected for monitoring. Frequent PAH determinations revealed that the ratio of Benzo(a- )Pyrene to total PAH on the Hi-Vol filters is relatively constant in ambient air from one sampling station to another.  相似文献   
117.
Emission factors of particulate-bound Polycyclic Aromatic Hydrocarbons (PAHs) including benzo(a)pyrene and, for the first time, the highly carcinogenic dibenzo(a,l)pyrene, dibenzo(a,e)pyrene, dibenzo(a,i)pyrene and dibenzo(a,h)pyrene have been determined in exhausts from two diesel- (DFVs) and two gasoline-fuelled light-duty vehicles (GFVs) operated in the Urban (AU), Rural Road (AR) and Motorway (AM) transient ARTEMIS driving cycles. The obtained results showed the DFVs to emit higher amounts of PAHs than the GFVs per km driving distance at low average speed in the AU driving cycle, while the GFVs emitted higher amounts of PAHs than the DFVs per km driving distance at higher average speeds in the AR and AM driving cycles. Furthermore, the study showed an increase in PAH emissions per km driving distance with increasing average speed for the GFVs with the opposite trend found for the DFVs. The GFVs generated particulate matter with higher PAH content than the DFVs in all three driving cycles tested with the highest concentrations obtained in the AR driving cycle. Dibenzo(a,l)pyrene was found to be a major contributor to the potential carcinogenicity accounting for 58–67% and 25–31% of the sum added potential carcinogenicity of the measured PAHs in the emitted particulate matter from the DFVs and GFVs, respectively. Corresponding values for benzo(a)pyrene were 16–25% and 11–40% for the DFVs and GFVs, respectively. The DFVs displayed higher sum added potential carcinogenicity of the measured PAHs than the GFVs in the AU driving cycle with the opposite trend found in the AR and AM driving cycles. The findings of this study show the importance of including the dibenzopyrenes in vehicle exhaust chemical characterizations to avoid potential underestimation of the carcinogenic activity of the emissions. The lower emissions and the lower sum added potential carcinogenicity of the measured PAHs found in this study for the GFVs compared to the DFVs in the AU driving cycle indicate the GFVs to be preferred in dense urban areas with traffic moving at low average speeds with multiple start and stops. However, the obtained results suggest the opposite to be true at higher average speeds with driving at rural roads and motorways. Further studies are, however, needed to establish if the observed differences between GFVs and DFVs are generally valid as well as to study the effects on variations in vehicle/engine type, ambient temperature, fuel and driving conditions on the emission factors.  相似文献   
118.
The Arctic environment, including sea ice, is changing. The impacts of these changes to Inuit and I?upiat ways of life vary from place to place, yet there are common themes as well. The study reported here involved an exchange of hunters, Elders, and others from Barrow, Alaska, USA, and Clyde River, Nunavut, Canada, as members of a larger research team that also included visiting scientists. Although the physical environments of Barrow and Clyde River are strikingly different, the uses of the marine environment by residents, including sea ice, had many common elements. In both locations, too, extensive changes have been observed in recent years, forcing local residents to respond in a variety of ways. Although generally in agreement or complementary to one another, scientific and indigenous knowledge of sea ice often reflect different perspectives and emphases. Making generalizations about impacts and responses is challenging and should therefore be approached with caution. Technology provides some potential assistance in adapting to changing sea ice, but by itself, it is insufficient and can sometimes have undesirable consequences. Reliable knowledge that can be applied under changing conditions is essential. Collaborative research and firsthand experience are critical to generating such new knowledge.  相似文献   
119.
Little is known about the evolution of large-bodied theropod dinosaurs during the Early to mid Cretaceous in Asia. Prior to this time, Asia was home to an endemic fauna of basal tetanurans, whereas terminal Cretaceous ecosystems were dominated by tyrannosaurids, but the intervening 60 million years left a sparse fossil record. Here, we redescribe the enigmatic large-bodied Chilantaisaurus maortuensis from the Turonian of Inner Mongolia, China. We refer this species to a new genus, Shaochilong, and analyze its systematic affinities. Although Shaochilong has previously been allied with several disparate theropod groups (Megalosauridae, Allosauridae, Tyrannosauroidea, Maniraptora), we find strong support for a derived carcharodontosaurid placement. As such, Shaochilong is the first unequivocal Asian member of Carcharodontosauridae, which was once thought to be restricted to Gondwana. The discovery of an Asian carcharodontosaurid indicates that this clade was cosmopolitan in the Early to mid Cretaceous and that Asian large-bodied theropod faunas were no longer endemic at this time. It may also suggest that the ascent of tyrannosaurids into the large-bodied dinosaurian predator niche was a late event that occurred towards the end of the Cretaceous, between the Turonian and the Campanian. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
120.
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