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31.
The Veneto region is one of the major tourist destinations in Italy, attracting some 20 million foreign and 24 million domestic arrivals each year through the variety of natural and cultural resources it has to offer. This paper examines the structure of foreign tourism, highlighting the importance of the Adriatic coast and Venice, and outlines some of the impacts which have resulted from the rapid and unplanned development of mass tourism. 相似文献
32.
We have computed estimates of the rate of vertical land motion in the Mediterranean Sea from differences of sea level heights measured by the TOPEX/Poseidon radar altimeter and by a set of tide gauge stations. The comparison of data at 16 tide gauges, using both hourly data from local datasets and monthly data from the PSMSL dataset, shows a general agreement, significant differences are found at only one location. Differences of near-simultaneous, monthly and deseasoned monthly sea level height time-series have been considered in order to reduce the error in the estimated linear-term. In a subset of 23 tide gauge stations the mean accuracy of the estimated vertical rates is 2.3 ± 0.8 mm/yr. Results for various stations are in agreement with estimates of vertical land motion from geodetic methods. A comparison with vertical motion estimated by GPS at four locations shows a mean difference of -0.04 ± 1.8 mm/yr, however the length of the GPS time-series and the number of locations are too small to draw general conclusions. 相似文献
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34.
Carola Hein 《GeoJournal》2000,51(1-2):83-97
The European Union has achieved internal cohesion and international economic recognition, but economics alone has not yet led to a united Europe. Although this cohesiveness strongly influence regions and cities, and cities have started to refer to their European background, the member nations continue to hold regional and urban planning power. Forced to take unanimous decisions, the European Council of Ministers maintained the doctrine of a unique capital for 40 years, provoking numerous urban and architectural visions while simultaneously accepting the existence of three provisional headquarters, Brussels, Strasbourg and Luxembourg. The host nations, Belgium, France and Luxembourg meanwhile oriented these cities to both European economic considerations and local needs.This article analyzes the logic that led to decentralization of the capital city functions, the reasons why cities were interested in hosting the European Communities, what individual cities and nations suggested and why the most obvious solutions were not adopted. The Maastricht Treaty, the ongoing strengthening of European and regional institutions, and the choice of the provisional headquarters as definite capitals in 1992 gives cause for hope that concepts based on European and regional necessities beyond the nation-state will now be elaborated. A European network of cities and regions including the three political capitals of Europe, as revealed by their infrastructures and buildings, seems to be the best expression of the meaning of European unity. 相似文献
35.
H. Inda F. García-Rodríguez L. del Puerto V. Acevedo D. Metzeltin C. Castiñeira R. Bracco J. B. Adams 《Journal of Paleolimnology》2006,35(4):699-713
Paleolimnological data are presented on trophic development, climatic change and sea level variations in Rocha Lagoon, a 72 km2 coastal lagoon in southern Uruguay. Using a sediment core that extended from 7000 to about 3700 yr BP, analyses of organic
matter, carbonate, diatoms and chrysophyte cysts were used to track the early Holocene paleolimnological conditions of Rocha
Lagoon. Opal phytoliths were also counted and identified, both temperature and humidity indices were calculated, and Opal
Phytolith Association Zones (OPAZ) were identified by performing Principal Coordinates Analysis (PCO). Diatom Association
Zones (DAZ) corresponding to marine/brackish and brackish/freshwater episodes were closely related to changes in trophic state.
Those DAZ representing marine/brackish stages exhibited a lower trophic state than those DAZ dominated by brackish and freshwater
diatoms. This highlights that during the first Holocene marine transgression, Rocha Lagoon did not continuously exhibit marine/brackish
conditions as reported in previous papers. Instead, three brackish/freshwater episodes related to sea level variation and
changes in humidity were identified. The first episode, by ~6000 yr BP, was related to sea level change as no significant
changes in either temperature or humidity indices were observed. The second episode, between 5000 and 4400 yr BP, was related
to both a sea level decrease and an increase in humidity, as a transition from humid to very humid climate was inferred. Concomitant
decreases in salinity and increases in trophic state were also observed. The third episode, after ~4000 yr BP, was related
to the end of the first Holocene regressive phase when sea level was slightly below present levels. Further decreases in salinity
and increases in trophic state were detected. The paleoclimatic trends inferred in this study were in close agreement with
other regional studies on climatic change, as cool temperatures were inferred. However, major changes in humidity were also
detected. A humid to very humid climate was inferred for ~7000–4500 yr BP, but the occurrence of a semiarid/arid climate was
inferred for ~4500–3700 yr BP. Our data suggest that during transgressive and regressive events there might be higher frequency
and lower amplitude sea level oscillations that might lead to changes in salinity and trophic state of coastal aquatic systems.
Such oscillations could only be tracked by high resolution analyses of sedimentary records and could be best interpreted with
complementary data on paleoclimate. In addition, microfossils such as diatoms and opal phytoliths were shown to be very sensitive
to such paleoenvironmental changes. 相似文献
36.
Carola Braun Christine Merk Gert Pönitzsch Katrin Rehdanz Ulrich Schmidt 《Climate Policy》2018,18(4):471-484
Climate engineering (CE) and carbon capture and storage are controversial options for addressing climate change. This study compares public perception in Germany of three specific measures: solar radiation management (SRM) via stratospheric sulphate injection, large-scale afforestation, and carbon capture and storage sub-seabed (CCS-S). In a survey experiment we find that afforestation is most readily accepted as a measure for addressing climate change, followed by CCS-S and lastly SRM, which is widely rejected. Providing additional information decreases acceptance for all measures, but their ranking remains unchanged. The acceptance of all three measures is especially influenced by the perceived seriousness of climate change and by trust in institutions. Also, respondents dislike the measures more if they perceive them as a way of shirking responsibility for emissions or as an unconscionable manipulation of nature. Women react more negatively to information than men, whereas the level of education or the degree of intuitive vs reflective decision making does not influence the reaction to information.
POLICY RELEVANCE
Current projections suggest that the use of climate engineering (CE) technologies or carbon capture and storage (CCS) is necessary if global warming is to be kept well below 2°C. Our article focuses on the perspective of the general public and thus supplements the dialogue between policymakers, interest groups, and scientists on how to address climate change. We show that in Germany public acceptance of potentially effective measures such as SRM or CCS-S is low and decreases even more when additional information is provided. This implies that lack of public acceptance may turn out to be a bottleneck for future implementation. Ongoing research and development in connection with CCS-S and SRM requires continuous communication with, and involvement of, the public in order to obtain feedback and assess the public’s reservations about the measures. The low level of acceptance also implies that emission reduction should remain a priority in climate policy. 相似文献
37.
Jutta Jahnel Christian Zwiener Thomas J. Gremm Gudrun Abbt‐Braun Fritz H. Frimmel Carola Kussatz Dieter Schudoma Werner Rocker 《洁净——土壤、空气、水》2001,29(4):246-253
Quality Targets for Pesticides and Other Pollutants in Surface Waters Surface waters are not only adversely affected by industrial and municipal wastewaters but also by diffuse sources. For the control of the ecological water quality, so‐called quality targets are set. The quality targets are threshold concentrations for hazardous substances related to the protected goods like water ecosystems, drinking water supply, sediments, or fishing. In this paper, quality targets for the protection of aquatic life in surface waters were derived on the basis of a concept developed by the International Commission for the Protection of the Rhine (Internationale Kommission zum Schutze des Rheins – IKSR). The quality targets for the selected hazardous substances, which mainly belong to the chemical class of pesticides, were calculated using ecotoxicological results for species of bacteria, algae, fish, and small crustaceans, as the four trophic standards of the water ecosystem. In cooperation with the Federal Environmental Agency (Umweltbundesamt – UBA) the effect data were taken from ecotoxicological data bases. According to the concept of the IKSR, the lowest test result for the most sensitive species was multiplied by an assessment factor. This proceeding concerns the difficulty in describing the complex interactions in water ecosystems with toxicity data of single laboratory experiments for a few organisms. For seven pesticides quality targets below 0.1 μg/L were proposed. These results show that the ecotoxicologically based quality targets might be even lower than the limit values for pesticides in drinking water of 0.1 μg/L. But for most of the substances the determined values are significantly higher. The great concentration range of quality targets demonstrates distinctly that one standard concentration for all pesticides could not be given with regard to the different effects on aquatic organisms. 相似文献