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111.
Although climate change is highly prevalent in the media, people in Europe and the United States are often unsure about climate change terms, processes, and its personal consequences. In other words, climate change communication seems to be largely failing so far. Among other communication tools, maps are widely used for explanatory purposes by scientists and the media. Here two questions arise: first, whether high map complexity may be too intricate to be understood and discourage people from deciphering the map; and second, whether personal interest in climate change can be influenced by the phenomenon depicted or the map’s scale. In a survey conducted among 109 students in the USA, 63% of respondents preferred a simple map, but a substantial subset, 37%, asked for complexity to receive more information. Regional phenomena evoked more concern than far-off phenomena (concern level index difference of 0.93 on a 5-ranked Likert scale). The advantage of maps showing local areas could not be statistically confirmed. 相似文献
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113.
Urban Computing is a branch of Pervasive Computing that investigates urban settings and everyday lifestyles. A large quantity of information to develop pervasive applications for urban environments is often already available, even if scattered and not integrated: maps, points of interest, user locations, traffic, pollution, and events are just a few examples of the digitalized information which we can access on the Web. Applications for mobile users that leverage such information are rapidly growing. In this article, we report our experience in addressing practical computational issues influencing the use of Geographic Information Systems and geospatial data from the standpoint of semantics and pervasive computing. We refer to the early achievements of the LarKC project, in which we developed an Urban Computing demonstrator. We highlight the positive sides of our experience and we discuss open issues and possible advances. 相似文献
114.
Irene Petrosillo Donatella Valente Nicola Zaccarelli Giovanni Zurlini 《Marine pollution bulletin》2009,58(10):1454-1461
The management of tourist harbors has traditionally been analyzed with little attention to managers’ awareness of the effects of their decisions on the environment. The aims of this paper were to assess managers’ perceptions of the main environmental risks in their regions and to identify common behaviors among the managers involved in eight tourist harbors in southern Italy, where the same tourist harbor is often managed by different managers. A questionnaire was administered and statistical analyses were performed to test differences between managers of big and small harbors. Managers showed a low perception of environmental risks and, surprisingly, in certain harbors, some meaningful cases were highlighted: the most homogeneous case, where all managers showed a reasonable level of environmental awareness, and cases with strong mismatches among managers. In this paper, we propose that an assessment of managers’ perceptions of risk be included as a new form of analysis when environmental risk assessments are carried out. 相似文献
115.
Meltwater from glaciers is not only a stable source of water but also affects downstream streamflow dynamics. One of these dynamics is the interannual variability of streamflow. Glaciers can moderate streamflow variability because the runoff in the glacierized part, driven by temperature, correlates negatively with the runoff in the non-glacierized part of a catchment, driven by precipitation, thereby counterbalancing each other. This is also called the glacier compensation effect (GCE), and the effect is assumed to depend on relative glacier cover. Previous studies found a convex relationship between streamflow variability and glacier cover of different glacierized catchments, with lowest streamflow variability at a certain optimum glacier cover. In this study, we aim to revisit these previously found curves to find out if a universal relationship between interannual streamflow variability and glacier cover exists, which could potentially be used in a space-for-time substitution analysis. Moreover, we test the hypothesis that the dominant climate drivers (here precipitation and temperature) switch around the suggested optimum of the curve. First, a set of virtual nested catchments, with the same absolute glacier area but varying non-glacierized area, were modelled to isolate the effect of glacier cover on streamflow variability. The modelled relationship was then compared with a multicatchment data set of gauged glacierized catchments in the European Alps. In the third step, changes of the GCE curve over time were analysed. Model results showed a convex relationship and the optimum in the simulated curve aligned with a switch in the dominant climate driver. However, the multicatchment data and the time change analyses did not suggest the existence of a universal convex relationship. Overall, we conclude that GCE is complex due to entangled controls and changes over time in glacierized catchments. Therefore, care should be taken to use a GCE curve for estimating and/or predicting interannual streamflow variability in glacierized catchments. 相似文献
116.
The occurrence of intersexuality in populations of the marine amphipod Echinogammarus marinus has been related to several causes, including anthropogenic contamination, microsporidian parasites and environmental sex determination (ESD). At the individual-level, the costs of intersexuality in E. marinus are reflected in reduced reproductive output of intersexes compared to normal specimens. The impacts of intersexuality and other reproductive disorders in nature will only be fully understood when individual-level effects are upscale to the population-level, which can be achieved through ecological models. The aim of the present work is to simulate the density variation of real populations of E. marinus with different intersexuality incidence, proportions of phenotypes and intersex female reproductive rates. To achieve that, we have incorporated empirical data obtained at the individual-level from three intersexed populations of E. marinus into a population dynamic model. The original model was calibrated and validated for a long-term stable population without intersexuality and sex ratio 1. In the present version, the model includes an extra population group, intersex females, but the total sum of flow rates from juveniles to adults was kept the same as in the original model to respect the previous validation. In these circumstances, results indicate that the male-biased population is very sensitive to intersexuality, even at low incidence levels, and exhibits significant density decrease if conditions do not change. On the contrary, the two populations with a preponderance of female-biased sex ratios, low or moderate intersexuality incidence (up to an average value of 9% of the population) and with intersex reproductive rates corresponding to 80% the value of normal specimens, exhibit long-term persistence.The model is highly sensitive to adult female parameters (e.g. mortality), indicating that small variations on its values can significantly change population responses.Overall the present results suggest that, in spite the costs of intersexuality in E. marinus, the temporal variation of intersexed populations depend on intersex incidence level, sex ratio fluctuations and reproductive output of intersexes. Simulations also suggest that other processes (e.g. mortality rates of normal females) may play important roles in the maintenance of populations with intersexuality. In the future, it will be crucial to improve and validate this type of models with long-term observations and monitoring of intersexed populations. 相似文献
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118.
Reconstruction of the environmental history of a coastal insular system using shallow marine records: the last three millennia of the Cíes Islands (Ría de Vigo,NW Iberia) 下载免费PDF全文
Castor Muñoz Sobrino Iria García‐Moreiras Natalia Martínez‐Carreño Víctor Cartelle Tania L. Insua Javier Ferreiro Da Costa Pablo Ramil‐Rego Carlos Fernández Rodríguez Irene Alejo Soledad García‐Gil 《Boreas: An International Journal of Quaternary Research》2016,45(4):729-753
The coastal lagoon‐beach complex at the Cíes Islands located at the opening of the Ría de Vigo (NW Iberia) is an important ecosystem currently threatened by anthropogenic impacts and climate variations. We used multiproxy marine sediment analyses to reconstruct the millennial environmental dynamics of this insular system and, in particular, the recent history of its coastal lagoon. Geophysical surveys were used to obtain bathymetry and identify the major sedimentary units of its closest submarine basin as well as their sediment sources. Core samples were taken in the middle and distal parts of the sedimentary body, where several prograding sedimentary units are thinner, allowing continuous sampling of the facies. Lithological, textural, elemental and chronological analyses were carried out on two cores. The detailed palynological studies on one of the cores included the analyses of the pollen, non‐pollen palynomorphs and dinocysts dating back three millennia. Our results revealed noticeable environmental changes affecting this area during the last 3000 years, due mainly to changing climate and oceanic conditions but also to the impact of historic human occupation of the islands. Several cold events (the 2.8 ka BP event and the Little Ice Age) characterized by enhanced upwelling alternated with warmer stormy periods of prevailing downwelling conditions in the ria. These circumstances altered the balance amongst the lacustrine, marsh, dune and lagoon systems, opening ephemeral inlets and modifying the trophic stage of the shallow waters surrounding the archipelago. Here we provide a background of the human and climatic impacts affecting these highly sensitive habitats, which may serve to improve their future management strategies. 相似文献
119.
Irene Zembo 《Sedimentary Geology》2010,223(3-4):206-234
The sedimentary record of the Val d'Agri basin is of great importance for understanding the Quaternary tectonic activity and climatic variability in the Southern Apennines. Changes in tectonic controls, sediment supply and climatic input have been identified. The interval from ~ 56 to ~ 43 ka was associated with asymmetric subsidence restricted to the north-eastern actively faulted margin of the basin and development of axial braided river and transverse alluvial fan systems. Short-lasting Mediterranean-type pedogenesis between ~ 43 and ~ 32 ka (MIS Stage 3) coexisted with progradation–aggradation of the southern alluvial fan deposits and southwards tilting of the basin floor. Aggradation ended with consumption of accommodation space after 32 ka. During a subsequent stage of decline of vegetation cover, possibly as a consequence of climatic cooling (probably MIS Stage 2), active progradation of alluvial fans occurred. Breakthrough of the basin threshold and entrenchment of the drainage network must therefore be attributed to a latest Pleistocene to Holocene age. The first stages of basin opening and fill, predating ~ 56 ka have only been inferred by stratigraphic considerations: the earliest lacustrine sedimentation should be middle Pleistocene or older in age. The following south-eastward basin widening allowed progradation of alluvial fan systems, which completely filled the lacustrine area (tentatively late middle Pleistocene). Pedogenesis in “Mediterranean-like” climate conditions caused the final development of a highly mature fersiallitic paleosol at the top of the fan surfaces, in areas of morpho-tectonic stability, plausibly during MIS Stage 5. The study results demonstrate the potential of applying a multidisciplinary approach in an intermontane continental settings marked by a relative rapid and constant tectonic subsidence and a high rate of sediment supply during the Pleistocene glacial–interglacial cycles. 相似文献
120.
Structural constancy, both across time and across variable conditions, is a necessary precondition for accurate forecasting. Physical systems exhibit structural constancy, but economic and social systems generally do not. In this paper we examine the effects of policy, technology, and price volatility in commodity markets on the relationship between soybean oil and petroleum prices. An early Energy Information Administration (EIA) forecast of soy-based biodiesel price projected a simple relationship between soybean oil demand and price into the future??a relationship that has little explanatory power over the recent price volatility in oilseed markets. We propose that structural inconstancy and new trading behavior better explain price movements in soybean oil, and we further argue that forecasters must invent new ways of addressing the fundamental epistemological challenge of structural inconstancy in economic and social systems. 相似文献