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991.
This paper presents a method for transforming the information of an engineering geological map into useful information for
non-specialists involved in land-use planning. The method consists of classifying the engineering geological units in terms
of land use capability and identifying the legal and the geologic restrictions that apply in the study area. Both informations
are then superimposed over the land use and a conflict areas map is created. The analysis of these data leads to the identification
of existing and forthcoming land use conflicts and enables the proposal of planning measures on a regional and local scale.
The map for the regional planning was compiled at a 1:50,000 scale and encompasses the whole municipal land area where uses
are mainly rural. The map for the local planning was compiled at a 1:10,000 scale and encompasses the urban area. Most of
the classification and operations on maps used spatial analyst tools available in the Geographical Information System. The
regional studies showed that the greater part of Analandia’s territory presents appropriate land uses. The local-scale studies
indicate that the majority of the densely occupied urban areas are in suitable land. Although the situation is in general
positive, municipal policies should address the identified and expected land use conflicts, so that it can be further improved. 相似文献
992.
The morphosedimentary evolution of a sector of the southern Espinhaco range (northern Minas Gerais State, Brazil) and its
regional neotectonic setting are presented herein. The studied site is a stream at base level flowing along the western border
of the range. Its identification was accomplished by using remote sensing techniques including the analysis of 3D slope models
generated with shuttle radar topography mission images. The main geomorphological features of the identified site were surveyed
in a 1:500 scale. In addition, seven stratigraphic logs are described. A regional geologic compilation and facies diagrams
were used as a basis for the integration of the geomorphological and stratigraphic data, which produced some conclusions about
the recent tectonic reactivations at the eastern border of Sao Francisco Craton. The results point to a local eastward tilting
of the Espinhaco range. This fact is in accordance with previous findings in neighboring areas and results in the asymmetric
evolution of the fluvial valley, as well as the regional relief. 相似文献
993.
Ekaterina Vasyukova Wolfgang Uhl Fuad Braga Claudia Simões Tânia Baylão Klaus Neder 《Environmental Earth Sciences》2012,65(5):1587-1599
Drinking water production at three waterworks was evaluated with respect to variable weather conditions in the Brasília Distrito
Federal. Results of the investigation revealed that seasonal variations in rainfall play an important role in influencing
the quality of the surface water sources used for drinking water production in the district. In most surface sources, particles
and apparent colour are likely to originate from erosion during rain events. This represents the primary challenge facing
waterworks, notably when the raw water qualities of the sources to be treated at one facility differ by one order of magnitude,
as well significantly varying from one season to the next. Treatment efficiencies in terms of turbidity, apparent colour and
dissolved organic carbon (DOC) removal were evaluated. Drinking water quality was found to be significantly influenced by
raw water quality at all considered treatment plants. With regard to DOC removal, treatment was most efficient in waterworks
which treated raw water with high percentages of biopolymers and humics. Most dissolved organics were removed by coagulation.
Finally, conclusions are drawn on how to better cope with challenges facing drinking water production in a tropical climate.
The first of these recommendations is the introduction of online turbidity and dissolved organic matter monitoring in order
to optimise the coagulation process for the removal of these two parameters. A combination of different coagulants could also
be considered for this process. Additional more sophisticated improvements to process stability, such as determination of
floc characteristics, introduction of artificial neural networks or the eventual upgrade of the treatment train using membrane
filtration, are also suggested. 相似文献
994.
Ryoko Fujiyoshi Hikaru Amano Yousuke Sakuta Kazumasa Okamoto Takashi Sumiyoshi Ivan Kobal Janja Vaupoti? 《Environmental Earth Sciences》2012,67(1):133-140
Carbon sources were estimated by measuring carbon isotope ratios (??13C and ??14C) with accelerator mass spectrometry (AMS) in forest soils of different lithology. Six locations were selected in temperate deciduous and coniferous stands in Slovenia (?irovski vrh, Idrija, Ko?evski Rog, Pohorje, Gori?nica, and Rakitna), where carbonate rocks consisting of limestone and dolomite are abundant as underlying bedrock. Carbon isotope fractionation would not have occurred in two carbonaceous soils, since the values of both ??13C and ??14C changed consistently in these soils after thermal (550°C, 2?h) or chemical (1?M HCl, 24?h) treatments. Organic components were found to be predominant carbon sources (70?C100%) in the uppermost portions (0?C2?cm in depth). In deeper portions at a depth of about 30?C35?cm, soil carbon may be derived completely from underlying carbonate minerals in Idria, western part of Slovenia. The Combination of heat and chemical treatments with AMS provides practical information on soil carbon sources in carbonaceous soils. 相似文献
995.
Geological and anthropogenic influences on sediment metal composition in the upper Paracatu River Basin, Brazil 总被引:1,自引:1,他引:0
Daniel Santos Mulholland Geraldo Resende Boaventura Daniel Ferreira Araújo 《Environmental Earth Sciences》2012,67(5):1307-1317
This work reports a geochemical study of sediments from the upper Paracatu River Basin. The objective is to define the influences of Au, Zn, and Pb mineral deposits and mining activities on the sediment metal sources, distribution, and accretion. The samples were analyzed using ICP/OES, AAS, and XRD techniques and were treated with principal components analysis and the geo-accumulation index. The main geochemical processes that control the sediment composition are pyrite oxidation, muscovite weathering, carbonate dissolution, and the erosion of oxisols enriched with Zn and Pb. The upper Rico Stream has high Al, Fe, Cu, Cr, Co, and Mn concentrations due erosion of oxisols and pyrite oxidation and muscovite alteration present in the parental rock. The artisanal alluvial gold mining increased the primary rock-minerals?? weathering and Hg sediment concentration. The lower Escuro River and Santa Catarina Stream are enriched with Zn and Pb due the erosion of metal-rich soils formed over galena, sphalerite, calamine, and willemite mineral deposits located upstream. Elements such as Ca, Mg, and Ba have low concentrations throughout the sampled area due the high solubility of these metals-bearing minerals. The dispersion of metals is limited by the basin geomorphology and their affinity to silt-clayey minerals and Fe and Mn oxides and hydroxides in circumneutral pH waters. 相似文献
996.
Andréhette Verster Daan de Waal Robert Schall Chris Prins 《Mathematical Geosciences》2012,44(1):91-100
The metallurgical recovery processes in diamond mining may, under certain circumstances, cause an under-recovery of large
diamonds. In order to predict high quantiles or tail probabilities we use a Bayesian approach to fit a truncated Generalized
Pareto Type distribution to the tail of the data consisting of the weights of individual diamonds. Based on the estimated
tail probability, the expected number of diamonds larger than a specified weight can be estimated. The difference between
the expected and observed frequencies of diamond weights above an upper threshold provides an estimate of the number of diamonds
lost during the recovery process. 相似文献
997.
Gerard W. Hazeu Arnold K. Bregt Allard J.W. de Wit Jan G.P.W. Clevers 《International Journal of Applied Earth Observation and Geoinformation》2011
Land cover and land use are important information sources for environmental issues. One of the most important changes at the Earth's surface concerns land cover and land use. Knowledge about the location and type of these changes is essential for environmental modeling and management. Remote sensing data in combination with additional spatial data are recognized as an important source of information to detect these land cover and land use changes. 相似文献
998.
Dayana Castilho de Souza Marcos Daisuke Oyama 《Theoretical and Applied Climatology》2011,103(3-4):345-357
The climatic impacts of gradual desertification in the semi-arid area of Northeast Brazil (SANEB) were evaluated using the MM5 regional model. Simulations for the rainy season of SANEB (March, April, and May) were performed. Desertification simulations were grouped into three numerical runs: total (all SANEB covered by desert), partial (desert areas placement based on future environmental degradation scenarios for SANEB), and random desertification (desert areas placed randomly within SANEB). Total desertification led to a pronounced and significant precipitation reduction in large parts of SANEB. Climatic impacts of partial desertification were guided by the southward expansion of desert areas. For intermediate desertification extensions, a dipole pattern with precipitation reduction (increase) in the northern (southern) areas of SANEB was found. Random desertification led to climatic impacts spread over the whole SANEB. In both partial and random desertification, a quasi-linear precipitation reduction was found as desertification extension increases. 相似文献
999.
J. Garc��a-Serrano B. Rodr��guez-Fonseca I. Blad�� P. Zurita-Gotor A. de la C��mara 《Climate Dynamics》2011,37(9-10):1727-1743
The dominant variability modes of the North Atlantic-European rotational flow are examined by applying a principal component analysis (PCA/EOF) to the 200?hPa streamfunction mid-winter anomalies (Jan?CFeb monthly means). The results reveal that, when this norm is used, the leading mode (EOF1) does not correspond to the traditional North Atlantic Oscillation (NAO, which appears in our analysis as the second leading mode, EOF2) but is the local manifestation of the leading hemispheric streamfunction EOF. The regression of this regional mode onto the global SST field exhibits a clear El Ni?o signature, with no signal over the Atlantic, while the associated upper height anomalies resemble the Tropical/Northern Hemisphere (TNH) pattern. East of North America, this TNH-like wavetrain produces a meridional dipole-like pattern at lower levels. Although in some ways this pattern resembles the NAO (EOF2), the dynamics of these two modes are very different in that only EOF2 is associated with a latitudinal shift of the North Atlantic stormtrack. Thus, the choice of the streamfunction norm in the EOF analysis allows the separation of two different phenomena that can produce similar dipolar surface pressure anomalies over the North Atlantic but that have different impact on European climate. These two modes also differ on their contribution to variability at lower levels: while NAO-EOF2 is mostly confined to the North Atlantic, TNH-EOF1 has a more annular, global character. At upper levels NAO-EOF2 also produces a global pattern but with no annular structure, reminiscent of the ??circumglobal?? teleconnection. 相似文献
1000.
Social models of population vulnerability to disasters increasingly include the notion that vulnerability has a strong temporal component. While this temporality is typically conceptualized as objective (making vulnerability “dynamic,” “multiscalar,” and/or “historical”), it consistently fails to acknowledge that among stakeholders managing hazardscapes temporality is also a social process in which subjective experience of time may play a role in creating situations of population vulnerability. This paper proposes that the temporal situatedness of a population relative to past hazard events and the quality with which stakeholders engage hazard memory-chains combine to significantly influences its vulnerability to natural hazards. It is proposed that this temporal vulnerability is characterized by shared, population level potential for surprise and can be evaluated by exploration of time-series depth and temporal reference points in historical ecological narratives and documents. Based on ethnohistoric research conducted from 2002 to 2006 in flood-prone eastern North Carolina (USA), it is illustrated how temporal vulnerability was relatively higher in the Neuse River watershed located at the City of Kinston than surrounding watersheds. Due to the combination of factors including the damming of the Neuse River in the 1980s, outdated official floodplain maps, relatively unmonitored floodplain development, the stochastic timing of flood events (placing the last major flood more than a generation away), technological optimism, and turnover of floodplain officials and residents, local stakeholders were seriously misinformed about the space-time risks involved both before and after the disaster of Hurricane Floyd (1999) happened. To deal with this inconsistency, the temporal rarity of Hurricane Floyd as a “500-year event” has been motivated and embraced by many in an effort to continue life-as-is. The paper proposes that the concept of temporal vulnerability is further explored and used as key dimension in the vulnerability sciences. 相似文献