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Simula o do saldo de radia o na Serra da Mantiqueira Simulation of net radiation in the Mantiqueira mountain  [cached]
Pabricio M. O. Lopes,Dalton M. Valeriano,Bernardo B. da Silva,Geber B. de A. Moura
Revista Brasileira de Engenharia Agrícola e Ambiental , 2013,
Abstract: A influência do desmatamento da Mata Atlantica sobre o microclima da Serra da Mantiqueira ainda n o é totalmente compreendida. Para conhecer as consequências do desmatamento sobre o clima serrano é necessário realizar estudos sobre o balan o de radia o na superfície. A falta de dados possibilita conjugar imagens de satélite com dados meteorológicos em um Sistema de Informa o Geográfica na determina o do balan o de radia o. O presente estudo teve por objetivo avaliar o modelo MTCLIM em dias de céu claro ou nublado para simular o balan o de radia o na Serra da Mantiqueira, divisa entre os estados de S o Paulo, Minas Gerais e Rio de Janeiro, Brasil. Imagens diárias, semanais e dezesseis dias do sensor MODIS disponíveis em 2003 foram utilizadas em rotinas específicas do MTCLIM. Alvos específicos foram selecionados para avaliar o comportamento do balan o de radia o. Observou-se que o balan o de radia o acompanhou a topografia local e é influenciado pelo tipo de uso da terra. Conclui-se que a temperatura da superfície contribui para aumentar a temperatura do ar implicando em diminui o do balan o de radia o sobre pastagem. O modelo MTCLIM demonstrou boa correla o para a temperatura do ar (R2 = 0,82) e para a radia o solar global (R2 = 0,71). The influence of deforestation of the Atlantic Forest on the microclimate of the mountain Mantiqueira is not yet fully understood. To understand the consequences of deforestation on the highland climate research is needed about the surface radiation balance. The lack of data allows combining satellite images with meteorological data in a Geographic Information System in determining the radiation balance. The study aimed to evaluate the MTCLIM model in cloudless days or cloudy sky and simulate the radiation balance in the Mantiqueira mountain, between S o Paulo, Minas Gerais and Rio de Janeiro, Brazil. Daily images, weekly and sixteen days MODIS available in 2003 were used in specific routines from MTCLIM. Specific targets were selected to evaluate the behavior of the radiation balance. It was observed that the radiation balance followed the local topography and is influenced by the type of land use. It follows that the surface temperature contributes to elevate the air temperature, resulting in lesser radiation balance on pasture. The MTCLIM model showed good correlation for air temperature (R2 = 0.82) and solar radiation (R2 = 0.71).
Interference of lee waves over mountain ranges
N. I. Makarenko,J. L. Maltseva
Natural Hazards and Earth System Sciences (NHESS) & Discussions (NHESSD) , 2011, DOI: 10.5194/nhess-11-27-2011
Abstract: Internal waves in the atmosphere and ocean are generated frequently from the interaction of mean flow with bottom obstacles such as mountains and submarine ridges. Analysis of these environmental phenomena involves theoretical models of non-homogeneous fluid affected by the gravity. In this paper, a semi-analytical model of stratified flow over the mountain range is considered under the assumption of small amplitude of the topography. Attention is focused on stationary wave patterns forced above the rough terrain. Adapted to account for such terrain, model equations involves exact topographic condition settled on the uneven ground surface. Wave solutions corresponding to sinusoidal topography with a finite number of peaks are calculated and examined.
Study of human occupation impacts in the Batedor river basin in the Mantiqueira mountain in the municipality of Cruzeiro, SP, Brazil
Rubens Torres Curvello,Getulio Teixeira Batista,Marcelo dos Santos Targa
Ambiente e água : An Interdisciplinary Journal of Applied Science , 2008,
Abstract: The study of hydrographic basins as territorial units integrating the management of hydric resources is essential to guarantee sustainable use of natural resources in these basins. The establishment of the Paraíba do Sul hydrographic basins committee, in 1994, determined the need for management planning information and integration actions in the Paraíba do Sul basin which incorporates a variety of industries and intense land use. The Batedor river, in the municipality of Cruzeiro, SP, flows into the Passa Vinte which is an affluent of Paraíba do Sul river. Its mouth is located at 22°31’0.63”S and 45°01’2.07”W. Its farthest water contributing source lies about 8.5 km, near the Itaguaré peak 2,308 m high, in the Mantiqueira mountain on the border of S o Paulo and Minas Gerais States. To characterize land use in the Batedor hydrographic basin, Landsat imagery and topographic charts were analyzed based on remote sensing and geoprocessing techniques. This paper describes the study of impacts related to land and water resources use in the Batedor river basin and the generation of support material for environmental education. Results has shown that this basin has good water supply, has no flooding risk and has several springs running down the Mantiqueira Moutain slopes that form young creeks with few meanders. Irregular human occupation for housing and subsistence agriculture, mainly banana plantations can be seen in deep slopes and riparian areas, as well as degraded pastures that indicate inappropriate land use and no conformance to pertinent legislation. The decrease in forest vegetation cover can cause severe erosion with significant soil loss and sediment deposition in the river, thus reducing water quality and regulated quantity. This basin is currently responsible for 70% of the water supply for the city of Cruzeiro, SP.
Pierced salt domes in the Persian Gulf and in the Zagros mountain ranges in southern Iran and their relationship to hydrocarbon and basement tectonics
J. Rahnama-Rad,G. Farhoudi,H. Ghorbani,Sh. Habibi Mood
Iranian Journal of Earth Sciences , 2009,
Abstract: The most enigmatic problems with the nearly 200 salt domes pierced in the Persian Gulf and in the Zagros Mountain Ranges (ZMR) in southern Iran, a unique morphology in the world, have been the matter of this study, which is based on a combination of field work, enhancement of satellite and aerial photographs etc. In the ZMR, structural anomalies are frequently associated with similar facies distribution patterns. In the eastern portion of the region, emergent salt plugs of Infra-Cambrian age exhibit the same alignment patterns. Such trends bear no apparent genetic relationship to the Tertiary folding responsible for the present Zagros fold belt, but rather indicate their affinity with linear basement features which are readily observable on Land sat imagery and aerial photographs. Bending of anticlines in the competent cover rock, combined with minor strike-slip faults and horizontal displacements of parts of folded structures, strongly point to the presence of these basement faults. The salt plugs, which have pierced cover rocks of up to 10000 m thick, are distributed on the Arabian Platform along regional basement faults. The area of diapir outcrops is bounded by the Oman Line to the east and by the Kazerun fault to the west. Pieces of the basement have been brought up to the surface on some of the salt domes. The fragments were transported by rotational ascent of the Hormuz Salt Formation to the present and former land surfaces. The recognition of features related to basement tectonics and realization of their implication in the control and modification of geological processes are important adjuncts to the search for hydrocarbon accumulations in this region. To our best knowledge, data of basement faults in the study area are scarce. Therefore, this study was carried out to determine basement faults and their relation to salt dome distribution. Considering the fold axes bending, the trend of the salt plugs and also the distribution of epicenters of the last century, numerous new basement faults are introduced in this paper.
Pedological and isotopic relations of a highland tropical peatland, Mountain Range of the Espinha?o Meridional (Brazil)
Horák, Ingrid;Vidal-Torrado, Pablo;Silva, Alexandre Christófaro;Pessenda, Luiz Carlos Ruiz;
Revista Brasileira de Ciência do Solo , 2011, DOI: 10.1590/S0100-06832011000100004
Abstract: the evolution of organic matter sources in soil is related to climate and vegetation dynamics in the past recorded in paleoenvironmental quaternary deposits such as peatlands. for this reason, a histosol of the mineralotrophic peatland from the pau-de-fruta special protection area - spa, espinha?o meridional, state of minas gerais, was described and characterized to evidence the soil constituent materials and properties as related to changes in environmental conditions, supported by the isotopic and elementary characterization of soil c and n and 14c ages. samples were collected in a depression at 1,350 m asl, where histosols are possibly more developed due to the great thickness (505 cm). nowadays, the area is colonized by vegetation physiognomies of the cerrado biome, mainly rocky and wet fields (campo rupestre and campo úmido), aside from fragments of semidecidual seasonal forest, called cap?es forests. the results this study showed that early the genesis of the analyzed soil profile showed a high initial contribution of mostly herbaceous organic matter before 8,090 ± 30 years bp (14c age). in the lower-mid holocene, between 8,090 ± 30 years ap (14c age) to ± 4,100 years bp (interpolated age), the vegetation gradually became more woody, with forest expansion, possibly due to increased humidity, suggesting the existence of a more woody cerrado in the past than at present. drier climate conditions than the current were concluded ± 2,500 years bp (interpolated age) and that after 430 years bp (14c age) the forest gave way to grassland, predominantly. after the dry season, humidity increased to the current conditions. due to these climate fluctuations during the holocene, three decomposition stages of organic matter were observed in the histosols of this study, with prevalence of the most advanced (sapric), typical of a deposit in a highly advanced stage of pedogenetic evolution.
A new species of Moneuptychia Forster (Lepidoptera: Satyrinae, Euptychiina) from the highlands of Southeastern Brazil
Freitas, André V.L.;
Neotropical Entomology , 2007, DOI: 10.1590/S1519-566X2007000600014
Abstract: this paper describes a new species of moneuptychia forster from the summits of the mantiqueira and espinha?o mountain ranges in southeastern brazil, details the morphology of adults and immatures of this species, and discusses the definition of the genus moneuptychia.
Nutrient addition does not enhance leaf decomposition in a Southeastern Brazilian stream (Espinha?o mountain range)
Abelho, M.;Moretti, M.;Fran?a, J.;Callisto, M.;
Brazilian Journal of Biology , 2010, DOI: 10.1590/S1519-69842010000400007
Abstract: a decomposition experiment using eucalyptus leaves was carried out in a southeastern brazilian mountain stream located at the transition between the cerrado and the atlantic forest to test whether nutrient addition increases microbial and invertebrate colonisation and accelerates breakdown rates. the results show that none of the tested variables was significantly affected by nutrient addition, despite the average increase in atp concentrations and invertebrate colonisation observed in the fertilised leaf bags. this could mean that breakdown in the stream was already at its maximum due to the relatively high water temperature and nutrient content, or that the breakdown rate of eucalyptus leaves was too fast to allow the detection of any effects of nutrient addition. breakdown rates of eucalyptus leaves were much faster than the values reported in literature for most species in brazilian cerrado streams, suggesting that the replacement of the natural vegetation by eucalyptus may affect nutrient dynamics in the region.
Are there signs of acidification reversal in freshwaters of the low mountain ranges in Germany?  [PDF]
C. Alewell,M. Armbruster,J. Bittersohl,C. D. Evans
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2001,
Abstract: The reversal of freshwater acidification in the low mountain ranges of Germany is of public, political and scientific concern, because these regions are near natural ecosystems and function as an important drinking water supply. The aim of this study was to evaluate the status and trends of acidification reversal after two decades of reduced anthropogenic deposition in selected freshwaters of the low mountain ranges in the Harz, the Fichtelgebirge, the Bavarian Forest, the Spessart and the Black Forest. In response to decreased sulphate deposition, seven out of nine streams investigated had significantly decreasing sulphate concentrations (all trends were calculated with the Seasonal Kendall Test). The decrease in sulphate concentration was only minor, however, due to the release of previously stored soil sulphur. No increase was found in pH and acid neutralising capacity (defined by Reuss and Johnson, 1986). Aluminum concentrations in the streams did not decrease. Thus, no major acidification reversal can currently be noted in spite of two decades of decreased acid deposition. Nevertheless, the first signs of improvement in water quality were detected as there was a decrease in the level and frequency of extreme values of pH, acid neutralising capacity and aluminium concentrations in streams. With respect to nitrogen, no change was determined for either nitrate or ammonium concentrations in precipitation or stream water. Base cation fluxes indicate increasing net loss of base cations from all ecosystems investigated, which could be interpreted as an increase in soil acidification. The latter was due to a combination of continued high anion leaching and significant reduction of base cation deposition. No major improvement was noted in biological recovery, however, initial signs of recovery were detectable as there was re-occurrence of some single macroinvertebrate species which were formerly extinct. The results of this study have important implications for water authorities, forest managers and policy makers: the delay in acidification reversal suggests a need for ongoing intensive amelioration of waters, a careful selection of management tools to guarantee sustainable management of forests and the reduction of nitrogen deposition to prevent further acidification of soils and waters. Keywords: freshwater, acidification reversal, drinking water supply, forested catchments, Germany
A statistical approach to modelling permafrost distribution in the European Alps or similar mountain ranges  [PDF]
L. Boeckli,A. Brenning,S. Gruber,J. Noetzli
The Cryosphere , 2012, DOI: 10.5194/tc-6-125-2012
Abstract: Estimates of permafrost distribution in mountain regions are important for the assessment of climate change effects on natural and human systems. In order to make permafrost analyses and the establishment of guidelines for e.g. construction or hazard assessment comparable and compatible between regions, one consistent and traceable model for the entire Alpine domain is required. For the calibration of statistical models, the scarcity of suitable and reliable information about the presence or absence of permafrost makes the use of large areas attractive due to the larger data base available. We present a strategy and method for modelling permafrost distribution of entire mountain regions and provide the results of statistical analyses and model calibration for the European Alps. Starting from an integrated model framework, two statistical sub-models are developed, one for debris-covered areas (debris model) and one for steep bedrock (rock model). They are calibrated using rock glacier inventories and rock surface temperatures. To support the later generalization to surface characteristics other than those available for calibration, so-called offset terms have been introduced into the model that allow doing this in a transparent and traceable manner. For the debris model a generalized linear mixed-effect model (GLMM) is used to predict the probability of a rock glacier being intact as opposed to relict. It is based on the explanatory variables mean annual air temperature (MAAT), potential incoming solar radiation (PISR) and the mean annual sum of precipitation (PRECIP), and achieves an excellent discrimination (area under the receiver-operating characteristic, AUROC = 0.91). Surprisingly, the probability of a rock glacier being intact is positively associated with increasing PRECIP for given MAAT and PISR conditions. The rock model is based on a linear regression and was calibrated with mean annual rock surface temperatures (MARST). The explanatory variables are MAAT and PISR. The linear regression achieves a root mean square error (RMSE) of 1.6 °C. The final model combines the two sub-models and accounts for the different scales used for model calibration. The modelling approach provides a theoretical basis for estimating mountain permafrost distribution over larger mountain ranges and can be expanded to more surface types and sub-models than considered, here. The analyses performed with the Alpine data set further provide quantitative insight into larger-area patterns as well as the model coefficients for a later spatial application. The transfer into a
Biomass burning contribution to black carbon in the Western United States Mountain Ranges
Y. H. Mao, Q. B. Li, L. Zhang, Y. Chen, J. T. Randerson, D. Chen,K. N. Liou
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2011,
Abstract: Forest fires are an important source to carbonaceous aerosols in the Western United States (WUS). We quantify the relative contribution of biomass burning to black carbon (BC) in the WUS mountain ranges by analyzing surface BC observations for 2006 from the Interagency Monitoring of PROtected Visual Environment (IMPROVE) network using the GEOS-Chem global chemical transport model. Observed surface BC concentrations show broad maxima during late June to early November. Enhanced potassium concentrations and potassium/sulfur ratios observed during the high-BC events indicate a dominant biomass burning influence during the peak fire season. Model surface BC reproduces the observed day-to day and synoptic variabilities in regions downwind of but near urban centers. Major discrepancies are found at elevated mountainous sites during the July-October fire season when simulated BC concentrations are biased low by a factor of two. We attribute these low biases largely to the underestimated (by more than a factor of two) and temporally misplaced biomass burning emissions of BC in the model. Additionally, we find that the biomass burning contribution to surface BC concentrations in the USA likely was underestimated in a previous study using GEOS-Chem (Park et al., 2003), because of the unusually low planetary boundary layer (PBL) heights in the GEOS-3 meteorological reanalysis data used to drive the model. PBL heights from GEOS-4 and GEOS-5 reanalysis data are comparable to those from the North American Regional Reanalysis (NARR). Model simulations show slightly improved agreements with the observations when driven by GEOS-5 reanalysis data, but model results are still biased low. The use of biomass burning emissions with diurnal cycle, synoptic variability, and plume injection has relatively small impact on the simulated surface BC concentrations in the WUS.
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