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31.
The latest scientific findings indicate that the increased concentration of greenhouse gases emitted by anthropogenic sources is significantly altering the balance of the global climate system. Considering forecasts of changes in the hydrological cycle and temperature related to global warming, the dynamics governing the functioning of the Pantanal Wetland, responsible for its rich biodiversity, find themselves threatened. Thus, this study was designed in the space-time of the Pantanal people called pantaneiros, and aims to discuss the Traditional Ecological Knowledge (TEK) of the Traditional Community Cuiabá Mirim regarding climate change. The information presented was obtained from 22 pantaneiros, between March 2008 and March 2010. The population sample was selected by the Snow Ball method. For data collection, semi structured interviews and oral histories were used. The results were compared with observations, simulations and projections of the IPCC AR4 for the region. The main findings of this research indicate that TEK presents itself as a crucial and complementary source of information for the development of local/regional adaptation strategies to climate change, bringing a distinct and relevant point of view from vulnerable stakeholders to the decision makers.  相似文献   
32.
Global climate change is a qualitatively distinct, and very significant, addition to the spectrum of environmental health hazards encountered by humankind. Historically, environmental health concerns have focused on toxicological or microbiological risks to health from local exposures. However, the scale of environmental health hazards is today increasing; indeed, the burgeoning human impact on the environment has begun to alter global biophysical systems (such as the climate system). As a consequence, a range of larger-scale environmental hazards to human population health has emerged. This includes the health risks posed by climate change, stratospheric ozone depletion, loss of biodiversity, stresses on terrestrial and ocean food-producing systems, changes in hydrological systems and the supplies of freshwater, and the global spread of persistent organic pollutants. Appreciation of this scale and type of influence on human health entails an ecological perspective — a perspective that recognises that the foundations of long-term good health in populations reside in the continued stability and functioning of the biosphere's "life-supporting" ecological and physical systems. This revised version was published online in September 2006 with corrections to the Cover Date.  相似文献   
33.
Studies on Brazilian archaeofauna from prehistoric and historic sites have attempted to explain human settlement and cultural trajectories in different geographical regions. However, only since 1999 have taphonomical criteria been developed during Brazilian zooarchaeological investigations. Wide ecosystem diversity results in the differential preservation of faunal remains. Until the end of the 20th century, many zooarchaeological studies presented insufficient information on complex predator–prey interaction systems in many regions, mostly from the Amazonian lowlands and the highlands of the Central Plateau. Animal remains might have been the result of natural predation, and they are often found mixed within anthropic material that could distort interpretation of deposits. Thus, there are major problems in defining diagnostic criteria to distinguish natural from cultural marks.Taphonomic analyses are needed to explain faunal remains in order to understand the particularities of human–animal relationships in Brazilian prehistory. Zooarchaeological and taphonomical data are presented from five human occupation sites dating from 9000 to 1000 BP to verify human–fauna relationships and natural deposits in three different regions of Brazil. These sites illustrate both natural and anthropic contexts.  相似文献   
34.
Voronoi Diagrams and Spatial Analysis of Crime   总被引:1,自引:0,他引:1  
A range of spatial analyses are used in the field of crime mapping, such as kernel density estimation, Ripley's K-function, and spatial autocorrelation, but there is limited use of Voronoi diagrams (VDs). The goal of this article is to contribute to the spatial analysis of crime through the use of VDs. We use four years of commercial robbery data from Campinas, Brazil, and employ several VD techniques: (1) We analyze crime concentrations through the properties of VDs—area and number of vertices—and coverage curve; (2) we introduce a new crime geovisualization with VD in three dimensions; and (3) we apply a network VD technique to crime analysis. The results demonstrate associations between these VD techniques and the ability of the researcher to recognize crime patterns associated with crime concentration, crime along pathways, and the highly regularized distribution of crime in limited areas spatially.  相似文献   
35.
Time series of wind-stress data, AVHRR and SeaWiFS satellite images, and in situ data from seven cruises are used to assemble a coherent picture of the hydrographic variability of the seas off the Northwest Iberian Peninsula from the onset (September-October) to the cessation (February-May) of the Portugal coastal counter current (PCCC). During this period the chemistry and the biology of the shelf, slope and ocean waters between 40° and 43°N have previously been undersampled. Novel information extracted from these observations relate to:
1.
The most frequent modes of variability of the alongshore coastal winds, covering event, seasonal and long-term scales;
2.
The conspicuous cycling between stratification and homogenisation observed in PCCC waters, which has key implications for the chemistry and biology of these waters;
3.
The seasonal evolution of nitrite profiles in PCCC waters in relation to the stratification cycle;
4.
The Redfield stoichiometry of the remineralisation of organic matter in Eastern North Atlantic Central Water (ENACW)—the water mass being transported by the PCCC;
5.
The separation of coastal (mesotrophic) from PCCC (oligotrophic) planktonic populations by a downwelling front along the shelf, which oscillates to and fro across the shelf as a function of coastal wind intensity and continental runoff; and
6.
The photosynthetic responses of the PCCC and coastal plankton populations to the changing stratification and light conditions from the onset to the cessation of the PCCC.
  相似文献   
36.
Nutrient Dynamics and Productivity in Three European Estuaries   总被引:3,自引:0,他引:3  
The Scheldt, Gironde and Sado estuaries exhibit quite different characteristics regarding the annual river discharges, nutrient loads and oxygen conditions. Distribution patterns of nutrients, dissolved oxygen, suspended matter and chlorophyll a as well as the nutrient ratios and half saturation constants, allow the identification and comparison of specific processes. The Scheldt emerges as the most eutrophic estuary being, in general, not nutrient limited and functions as a source of phosphorus and nitrogen. Intense biogeochemical processes take place in this system. The Sado is shown to be a moderately productive system, the upper part being enriched in nutrients and chlorophyll a and showing a tendency for oxygen depletion in summer. Different factors seem to control phytoplankton production along the salinity gradient: light regime landwards and nitrogen seawards. By contrast, the Gironde does not show clearly the presence of sinks or sources regarding nutrients and exhibits a reduced productivity essentially controlled by turbidity. The high amounts of particles seem also to be responsible for localized processes such as phosphate sorption/desorption and silicate regeneration.  相似文献   
37.
Maia  M.  Moreira  N.  Vicente  S.  Mirão  J.  Noronha  F.  Nogueira  P. 《Geology of Ore Deposits》2020,62(6):508-534
Geology of Ore Deposits - The Mociços Cu-deposit is part of a cluster of ancient copper mines in the Sousel-Barrancos metallogenic belt in the Ossa-Morena Zone at the SW Iberia. The orebodies...  相似文献   
38.
Ocean Dynamics - Near-inertial oscillations (NIO) are intermittent motions with a frequency close to the inertial frequency and represent an important fraction of the energy to the currents in the...  相似文献   
39.
40.
Ocean Dynamics - This paper evaluates the performance of the spectral wave model WAVEWATCH III for the South Atlantic Ocean forced by wind inputs from the most recent reanalyses, NCEP/CFSR and...  相似文献   
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