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91.
In Switzerland, communities are encouraged to define and to report on local Agenda 21. This paper presents an analysis framework to help local communities set sustainable development priorities and to follow through with appropriate actions. Four Swiss communities, from the French-speaking part of Switzerland, actively follow the project: Lausanne (114 304 citizens), Vevey (15 364 citizens), Mannens-Grandsivaz (505 citizens) and Essertines/Yverdon (666 citizens). The analysis framework developed is constituted of four interdependent fields: the societal characteristics, the individual or collective behaviours, the end objectives or sustainability impacts and the inhabitant's perception of these three fields. The link between society and behaviour can be studied through sociological analyses. The link between behaviour and environmental impact can be established thanks to Life Cycle analysis and Input/Output analyses. At each level, sustainable development indicators can be defined. As an application of the framework, the citizen energy consumption has been studied and expressed in energy slaves (= 3150 MJ/Year). A Swiss citizen needs altogether 69 slaves, 20 for his private consumption of goods and services, 19 for housing, 11 for transport, I1 for food and 8 for his consumption of public goods. If one fifth of the inhabitants of Lausanne, wanting to live closer to nature, actually moved out of town, the region would need 10 436 more slaves for 3500 persons happily living in the countryside.  相似文献   
92.
Fighting is a fundamental determinant of male fitness in species where females prefer socially dominant males as mates or where dominants can prevent subordinates from mating. This in turn can lead to the evolution of honest inter- and intra-sexual cues of male dominance. Fighting as a behaviour comprises both fighting rate (number of fights per unit of time) and fighting performance (success in winning fights), but it is not always clear which of these components are important for female choice and how they link to signals of male quality. To quantify the relative importance of fighting as a cue for females, we recorded detailed behavioural data from male black grouse Tetrao tetrix at leks. We explored the relationship between phenotypic traits (body mass, eye comb size, tail (lyre) length and blue chroma colouration) and fighting performance and rates and how these were related to male mating success. In older males' pairwise fights, winners had lower blue chroma than losers, but there were no differences in other morphological traits. In yearlings, no morphological trait predicted success in pairwise contests. Both fighting rate and performance were positively related to the number of copulations acquired by a male; however, when controlled for lek centrality, fighting performance and not fighting rate was significantly related to mating success. Our results indicate that females may be using components of fighting behaviour as cues for mate choice.  相似文献   
93.
In order to simulate a simple entraining geophysical flow, a viscous Newtonian gravity current is released from a reservoir by a dam-break and flows along a rigid horizontal bed until it meets a layer of entrainable material of finite depth, identical to the current. The goal is to examine the entrainment mechanisms by observing the interaction between the incoming flow and the loose bed. The sole parameter varied is the initial volume of the gravity current, thus altering its height and velocity. The gravity current plunges or spills into the entrainable bed and the velocity of the flow front becomes linear with time. The bed material is directly affected: motion is generated in the fluid far downstream of, and in that lying beneath the encroaching front. Shear bands are identified, separating horizontal flow downstream from flow with a strong vertical component close to the step. Downstream of the step the flow is horizontal and stratified, with no slip on the bottom boundary and very low shear near the surface. Between these two regions may lie transitional zones with linear velocity profiles, separated by horizontal bands of high shear; the number of transitional zones in the cross-section varies with the initial volume of the dam-break.  相似文献   
94.
Environmental and Ecological Statistics - Because of the dramatic changes that are being observed in the climatic conditions of the world, such as excess of rains, drought and huge floods, we...  相似文献   
95.
Since the 1960s, the development of the Serre-Chevalier winter and summer resort has led to a rapid extension of the urban fabric on the territory of the village of St-Chaffrey. On July 9, 1981, the new neighborhoods built on the alluvial fan of the Verdarel torrent were partly devastated by a channeled debris flow. This disaster prompted the civil authorities to set up an extensive fluvial regulation system, which rapidly contributed to recreating a climate of confidence and security favorable to continuing urban expansion. The combination of catastrophic floods in July 1995, and a new security-oriented national policy on natural hazards, nevertheless led to a return to precautionary measures. The St-Chaffrey town council has therefore been forced by the State to accept a building-free zone on the land-use plan. This measure is perceived as a real denial of the local efficacy of the flood and landslide risk management policy as carried out by the council of St-Chaffrey during the previous 20 years.  相似文献   
96.
To better assess the seasonality in the fallout of heavy metals to central Greenland, a continuous series of 68 snow samples has been collected at a remote site in the Summit area from a 2.7 m pit using ultraclean sampling procedures. This covers a continuous four year time period from spring 1991 to spring 1995. Co, Cu, Zn, Mo, Rh, Pd, Ag, Cd, Sb, Pt, Pb, Bi and U were determined using ultrasensitive inductively coupled plasma sector field mass spectrometry under clean room conditions. In addition we also determined Al by graphite furnace atomic absorption spectrometry and Na+, Ca2+, SO4(2-), MSA and oxalate by ion chromatography, species that will assist in the interpretation of the trace metal data. The data show pronounced inter- and intra-annual variations, with large differences in the amplitude of these variations for the element studied, with few clear seasonality patterns. Generally, high concentrations are observed in the spring snow layers, while much lower concentrations are typical of summer snow layers. Significant correlations are observed between Co, Cu, Zn, Ag and Sb, while Pt, Pd and Rh show no correlation with the other metals. Crustal enrichment factors show that while the crustal dust contribution is probably important for some metals for part of the year (spring), anthropogenic inputs are as important in many instances. Pronounced intra-annual variations are observed for some metals, in particular Pt. The variations observed for this metal parallel fairly closely changes in Russian Pt production, which points to emissions from smelters in the Russian Arctic as likely sources for Pt.  相似文献   
97.
Courtship and body condition of male two-spotted gobies (Gobiusculus flavescens) harbouring naturally acquired microsporidian infections were compared with those of microsporidian-free males under standardized conditions in the lab. Although parasite infection had no apparent effect on individual condition, it significantly affected male courtship intensity. This effect, however, was affected by the intensity of the female courtship. Our study is one of the first to demonstrate a sub-lethal behavioural effect of a microsporidian parasite that could negatively affect the reproductive success of infected individuals. Our results also suggest that secondary sexual traits like courtship may be more sensitive to moderately detrimental effects of parasite infection than classical condition indices.  相似文献   
98.
Food and Environmental Virology - The leading causes of foodborne viral disease outbreaks are human norovirus and hepatitis A virus (HAV). Their environmental persistence enables contamination of...  相似文献   
99.
To be rightly implemented, an environmental policy ought to set an institutional framework (goals, rules and instruments) which incents decentralised actors to adopt the appropriate range of technologies. In the household waste management policy, the development of valorisation techniques (and particularly recycling) must be supported by convenient instruments and incentives. The paper analyses the problems encountered with the French household waste policy to ensure the takeoff of recycling techniques. At the moment, a rather under-proportioned institutional setting leads to favour the adoption of incineration with energy recovery at the expenses of recycling. This tends to create a structural bias in favour of incineration.  相似文献   
100.
The duration of periods spent ashore versus foraging at sea, diving behaviour, and diet of lactating female Antarctic (Arctocephalus gazella, AFS) and subantarctic (A. tropicalis, SFS) fur seals were compared at Iles Crozet, where both species coexist. The large disparity in lactation duration (SFS: 10 months, AFS: 4 months), even under local sympatry, has led to the expectation that AFS should exhibit higher foraging effort or efficiency per unit time than SFS to allow them to wean their pups in a shorter period of time. Previous evidence, however, has not supported these expectations. In this study, the distribution of foraging trip durations revealed two types of trips: overnight (OFT, <1 day) and long (LFT, >1 day), in common with other results from Macquarie Island. However, diving behaviour differed significantly between foraging trip types, with greater diving effort in OFTs than in LFTs, and diving behaviour differed between fur seal species. OFTs were more frequent in SFS (48%) than in AFS (28%). SFS performed longer LFTs and maternal attendances than AFS, but spent a smaller proportion of their foraging cycle at sea (66.2 vs. 77.5%, respectively). SFS dove deeper and for longer periods than AFS, in both OFTs and LFTs, although indices of diving effort were similar between species. Diel variation in diving behaviour was lower among SFS, which foraged at greater depths during most of the night time available than AFS. The diving behaviour of AFS suggests they followed the nychthemeral migration of their prey more closely. Concomitant with the differences in diving behaviour, AFS and SFS fed on the same prey species, but in different proportions of three myctophid fish (Gymnoscopelus fraseri, G. piabilis, and G. nicholsi) that represented most of their diet. The estimated size of the most important fish consumed did not vary significantly between fur seal species, suggesting that the difference in dive depth was mostly a result of changes in the relative abundance of these myctophids. The energy content of these fish at Iles Crozet may thus influence the amount and quality of milk delivered to pups of each fur seal species. These results contrast with those found at other sites where both species coexist, and revealed a scale of variation in foraging behaviour which did not affect their effort while at sea, but that may be a major determinant of foraging efficiency and, consequently, maternal investment.  相似文献   
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