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71.
High-quality food and general good health are fundamental needs that have to be satisfied if society is to attain a high standard of living. Accordingly, a great deal of effort is expended in order to guarantee a high quality of food and ensure healthy living conditions. Among other things, these efforts entail massive substance flows. Significant substance flows are connected with the production and consumption of food and can be regarded from an economic, social, or environmental point of view. Substance flows are a part of both nature and the anthroposphere. This study demonstrates that food production at present is not linked to societal issues of production and sustainability; rather, it shows that a systematic approach and an analysis of issues and measures to be taken are required. This interconnectedness can be described as a timescape, in analogy to a landscape. For proper orientation in a landscape, a map is helpful, especially in combination with a compass. In the same way, we need a temporal orientation. Time scales serve as a compass to give orientation. A complete temporal analysis that includes all relevant temporalities provides the information that is encoded in a map. What has to be learned and exercised is the reading of such temporal maps. One method of doing this is temporal impact analysis (TIA). Temporal impact analysis brings issues that are not normally focused on into the foreground. It allows a better understanding of the implications of certain substance flows and the measures necessary for their management, and it provides an opportunity to develop a more sustainable management of substance flows. 相似文献
72.
Plutonium isotopes in the Rh?ne River originate from both the weathering of the catchment basin contaminated by global atmospheric fallout, and the liquid effluents released from the Marcoule reprocessing plant since 1961. Due to a new treatment process applied to the liquid effluents, a decrease of two orders of magnitude in the industrial plutonium discharged into the River Rh?ne has been registered from 1991. Today, 238Pu industrial inputs to the River Rh?ne are still about 10 times higher than those derived from global fallout, while 239+240Pu inputs from industrial and global fallout sources are of similar importance, i.e. 1 GBq y(-1). Our results indicate that the river sedimentary compartment act either as a sink or a delayed-source term of plutonium for the freshwaters depending on the hydraulic regime and flood events. This compartment may then represent an important industrial delayed-source term for the River Rh?ne freshwaters in the coming years as the Marcoule reprocessing plant is being dismantled. These results were obtained from samples collected from the lower course of the River Rh?ne over the 1987-1998 period and analysed for 238Pu and 239+240Pu activities. Both river sedimentary inventories of plutonium isotopes and effective outputs from the River Rh?ne towards the Gulf of Lions have been estimated for each year over the 1945-2000 period. Regarding 239+240Pu, the sedimentary inventory accumulated since 1945 is estimated to be 172+/-35 GBq. If mobile, this amount represents a significant delayed-source term of plutonium on the scale of the Rh?ne watershed. 相似文献
73.
Sabine Bauer Volker Witte Melanie Böhm Susanne Foitzik 《Behavioral ecology and sociobiology》2009,64(1):45-56
Ant social parasites use chemical warfare to facilitate host colony takeover, which is a critical but recurring step in their life cycle. Many slave-making ants use the secretion of the Dufour gland to manipulate host behaviour during parasitic nest foundation and slave raids. Harpagoxenus sublaevis applies this chemical weapon onto defending Leptothorax host workers, which elicits deadly fights amongst them. Host species are expected to evolve counter-adaptations against this behavioural manipulation and in this study we investigated the geographic structure of this co-evolving trait. We compared the effectiveness of the parasitic gland secretion from different H. sublaevis populations in host colonies from various sites and analysed the occurrence of local adaptation. The two host species L. muscorum and L. acervorum generally showed different responses to the parasites’ chemical weapon: L. acervorum attacked nestmates treated with Dufour gland secretion, while L. muscorum workers fled. Flight, instead of intraspecific fights, is an adaptive host reaction as it results in fewer host fatalities during raids. Beside interspecific host differences, we found a geographic mosaic of host resistance: parasites from a German population strongly manipulated the behaviour of both sympatric Leptothorax populations. Russian or Italian hosts instead did not react with intracolonial aggression, but fled when confronted with the gland secretion of their sympatric parasite. Not only variation in host resistance explains differences in the effectiveness of the parasitic gland secretion but also interpopulational differences in its chemical composition, which were revealed by gas chromatography and mass spectrometry. 相似文献
74.
Sustainable regional development as a politically requested concept challenges regions within the European Union since the Amsterdam Treaty 1997. A growing body of literature identifies cooperation between stakeholder groups as one of the limiting factors for implementing sustainable regional strategies. This leads to the question, how cooperation within a region could be organised. How can institutions support the implementation process of sustainable development on the regional level? Regional institutions are both supporters of cooperation between regional stakeholders and key players in regional development processes. Their connections strengthen the importance of networks in the sustainable regional development process. 相似文献
75.
The energy consumption of Paris and its supply areas from the eighteenth century to the present 总被引:1,自引:1,他引:1
Since the eighteenth century and the industrial revolution, cities have experienced great changes in their metabolism, and particularly in their energy consumption: transitions from one energy source to another, growing per capita consumption, and total consumption to cite but a few. These changes also impact urban energy supply areas and supply distance. This paper estimates Paris??s energy demand in both final and primary terms since the eighteenth century and gives an illustration of long-term socio-ecological interactions in an interdisciplinary perspective, connecting energy flow analysis, and historical research. It gives an overview of energy supply areas and assesses the distance between supply sites and the city. Paris??s annual total energy requirement (TER) was about 19?GJ per capita at the beginning of the eighteenth century and reached 30?GJ per capita in 1800; the supply area remained nearly the same with an average supply distance (Davg) of 200?km. During the nineteenth century, Paris??s population increased fivefold, and energy transitioned from biomass to fossil fuel. Per capita TER remained stable, whereas Paris??s supply area moved progressively toward coal basins, in connection with the tremendous change in transport systems. As a consequence, the Davg grew to 270?km around 1870. During the twentieth century, and especially since the Interwar period, per capita TER increased considerably (to 26?GJ/cap/year in 1910, 47?GJ/cap/year in 1946 and 126?GJ/cap/year in 2006). The internationalization of the energy supply and the shift to petroleum and natural gas also increased the remoteness of the supply sites: the Davg equaled 3850?km in 2006. 相似文献
76.
Dissolved uranium ((238)U(D)) was measured within the Gironde fluvial-estuarine system (France), which is well known for its heavy metal pollution and its subsequent environmental effects. Dissolved (238)U activities exhibit the highest levels and variability in the small watersheds of the Isle and Riou-Mort rivers, ascribed to low discharges and the occurrence of peculiar features (local U ore deposits; Permian layers). The major tributaries of the Gironde Estuary: Garonne, Lot and Dordogne, show rather stable (238)U(D), higher than the global mean riverine uranium activity. In the Gironde Estuary (238)U(D) behaves conservatively along the river-estuary-ocean transect. Dissolved (238)U distribution in the Gironde fluvial-estuarine system can be explained by the characteristics of considered drainage basins. There is no evidence of anthropogenic pollution. 相似文献
77.
Wolfgang Cramer Uta Fritsch Rik Leemans Sabine Lütkemeier Dagmar Schröter Allan Watt 《Regional Environmental Change》2008,8(3):125-134
Biodiversity is essential for multiple aspects of human life and well-being, but many current assessments of the functioning
of biodiversity and ecosystems, understanding of risks posed by environmental change and the best practice of their management
of ecosystems are lacking a unified scientific and conceptual basis. Methods such as scenario analysis, and terms such as
ecosystem services, are widely used, but their meaning is understood in many different ways depending on context, user needs
and experience of researchers. In order to advance the conceptual basis for ecosystem analysis and management in a rapidly
changing world, as well as the ability of young scientists to reflect upon these concepts, we have organised five 2-week-long
summer schools in Peyresq, a remote village in the Southern French Alps. In total 173 participants have worked intensively
with 69 experienced researchers and a team of conveners and tutors in order to discuss a broad range of views on topics on
ecosystem analysis and functioning. Topics ranged from conditions of and threats to various ecosystems due to environmental
change, models and scenarios for assessment, stakeholder perceptions and needs for information, to the social and economic
contexts for biodiversity. We report our experience from these schools, present the training concept which has emerged from
them and suggest lines of further development.
相似文献
Wolfgang CramerEmail: |
78.
79.
The criteria currently used to determine the extent of novel forest decline areleaf loss andyellowing of leaves. However, these criteria have only a limited value for indicating damage of woody trees, especially the early stages. Therefore, physiological-biochemical parameters will be useful to measure the extent of forest decline. Results from several natural spruce stands indicate that in needles with early signs of damage and needles with severe damage PEPC activity is significantly higher than in needles of healthy plants. Therefore, PEPC activity can reveal beginning damage and may be used as abiochemical indicator for damage assessments of spruce. The influence of air pollutants on PEPC activity in spruce needles was measured in fumigation chambers and open-top chambers; PEPC activity was shown to be affected by long-term exposition only. 相似文献
80.