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Calibra??o do "simplified simple biosphere model - SSiB" para áreas de pastagem e floresta na Amaz?nia com dados do LBA
Correia, Francis Wagner Silva;Alvalá, Regina Célia dos Santos;Manzi, Ant?nio Ocimar;Gielow, Ralf;Kubota, Paulo Yoshio;
Acta Amazonica , 2005, DOI: 10.1590/S0044-59672005000200017
Abstract: the parameters of the simplified simple biosphere model - ssib were validated and subsequently calibrated for the fazenda nossa senhora aparecida (62o22'w; 10o45's) pasture site and the reserva biológica do jaru (62o22'w; 10o45's) forest site, both located in the state of rond?nia. micrometeorological and hydrological data collected during the dry period of 2001, as part of the large-scale biosphere-atmosphere experiment in amazonia - lba, were used. the results showed that the model simulated well the net radiation, both at the pasture and at the forest. the latent heat flux was super-estimated in both sites. the model sub-estimated the sensible heat flux at the pasture and at the forest, mainly during the night period; notwithstanding, the values for the forest were nearer to the observed ones. with the calibrated parameters, the model generated better estimations of the latent and the sensible heat fluxes, thus better representing the energy partition both at the forest and at the pasture.
Verifica o do fator de calibra o e indicador da qualidade do feixe de aceleradores lineares  [cached]
Silva Maria da Penha,Mota Helvécio Correa,Almeida Carlos Eduardo V. de
Radiologia Brasileira , 2001,
Abstract: Um programa de garantia da qualidade é um pré-requisito obrigatório para a exatid o necessária em radioterapia. Este trabalho relata parte dos testes de rotina mensal do controle da qualidade dos aceleradores lineares do Instituto Nacional do Cancer, relativos à calibra o dos feixes de fótons e elétrons, no período de dois anos. Os resultados foram comparados com as recomenda es do protocolo AAPM TG-40. Na análise do fator de calibra o para o feixe de fótons foi encontrado um desvio máximo de 12%; para o feixe de elétrons o maior desvio encontrado foi 10%. A flutua o observada no indicador da qualidade do feixe para os feixes de elétrons foi maior que para os feixes de fótons. Os resultados confirmam a importancia de um programa de garantia da qualidade em um servi o de radioterapia, permitindo corre es rápidas da dose administrada ao paciente.
Fluxos de CO2 do solo na floresta nacional de Caxiuan , Pará, durante o experimento ESECAFLOR/LBA Soil CO2 efflux in Caxiuan national forest, Pará, during the ESECAFLOR/LBA experiment  [cached]
Jo?o de Athaydes Silva Júnior,Antonio Carlos L?la da Costa,Pedro Vieira de Azevedo,Rafael Ferreira da Costa
Revista Brasileira de Meteorologia , 2013,
Abstract: O experimento ESECAFLOR/LBA foi conduzido na Floresta Nacional de Caxiuan , Pará, e este artigo procura investigar os efeitos do estresse hídrico sobre a respira o do solo. Duas parcelas de 1 hectare foram instaladas em janeiro de 2002. Uma parcela (A) permaneceu em condi es naturais e foi usada como controle, enquanto que na parcela de exclus o (B) foram instalados painéis plásticos para que aproximadamente 70% da precipita o fosse excluída. Os dados foram coletados mensalmente de janeiro a dezembro de 2005. Durante o ano de 2005 houve 2.211,6 mm de precipita o na ECFPn, ou seja 9,96% acima da média de 2.011,2 mm. As médias da umidade do solo foram de 15,6±9,2 e 9,5±3,4% nas parcelas A e B, respectivamente. As médias da temperatura do solo para as parcelas A e B foram de 25,6±0,4 e 25,7±0,5 oC, respectivamente. As médias dos fluxos de CO2 no solo nas parcelas A e B foram de 3,46±0,44 e 3,21±0,84 μmolCO2 m-2s-1, respectivamente. Com a exclus o de parte da chuva na parcela B, houve uma redu o de 7,23% nos fluxos de CO2 no solo (0,25 μmolCO2 m-2s-1), 39,1% na umidade do solo (6,1p.p.), e um aumento de 0,39% na temperatura do solo (0,1oC). A umidade do solo na parcela B foi menor do que na parcela A, devido ao sistema de exclus o da chuva, no entanto no início do ano, devido a reformas que o mesmo passou esses valores estiveram próximos. The ESECAFLOR/LBA experiment was carried out at the Caxiuan National Forest, Pará State, and this article intends to investigate the effect of hydrological stress on the total soil respiration. Two adjacent 1 hectare plots were defined in January 2002. One plot remained in its natural conditions and was used as a control (A), while in the exclusion plot (B) plastic cover panels were installed in order to drain about 70% of the total rainfall to outside of the plot. Accumulated monthly rainfall was recorded from 2005 January to December. During 2005 the rainfall over the ECFPn was 2,211.6 mm, or 9.96% above the mean of 2,011.2 mm. The average soil moisture was 15.6±9.2 and 9.5±3.4% in the plots A and B, respectively. The average soil temperature was 25.6±0.4 and 25.7±0.5 oC, for the A and B plots, respectively. The average soil CO2 flux was 3.46±0.44 and 3.21±0.84 μmolCO2 m-2s-1 in the A and B plots, respectively. With the exclusion of part of rain in plot B, it had a reduction of 7.23% in the soil CO2 flux (0.25 μmolCO2 m-2s-1), 39.1% in the soil humidity (6.1p.p.), and an increase of 0.39% in the soil temperature (0.1oC). The soil moisture in parcel B was lesser than in the parcel A, due to the exclusion system of r
Dimens?es humanas do uso e cobertura das terras na Amaz?nia: uma contribui??o do LBA
Batistella, Mateus;Moran, Emilio F.;
Acta Amazonica , 2005, DOI: 10.1590/S0044-59672005000200014
Abstract: an understanding of changes in amazonian landscapes depends on documentation about alterations in land cover. this article highlights the efforts of the large scale biosphere-atmosphere experiment in amaz?nia (lba) related to the topic. in particular, a longitudinal study has analyzed the social and biophysical dimensions of land use/land cover, using a multi-scalar georeferenced approach. the study areas represent a gradient of soil fertility in amaz?nia and include distinct landscape mosaics, from the amazon estuary and the bragantina region to northeastern rond?nia. within the project, we emphasize studies in areas of rural settlement due to their social relevance and their impacts on land cover in local and regional scales. to illustrate the potential of such studies, we present comparative results for machadinho d'oeste and vale do anari, state of rond?nia. the multitemporal analysis included landsat images and fieldwork. land owners, loggers, rubber tapers, and other local actors were interviewed about their production systems and land-use history. the calculation of spatial metrics supported our conclusions. the results indicate that settlement design and institutional aspects play a central role in the process of landscape change. the combination of private lots with communal forest reserves, managed by local populations, produces positive outcomes in maintaining larger patches of forest. the methods used contribute to the analysis, integration, and monitoring of land use and land cover in amaz?nia, subsidizing policies that incorporate the social and environmental dimensions of regional development.
Compara??o do perfil de vento medido por Radiossondas e por um SODAR durante o experimento DRYTOWET-AMC/LBA
Santos e Silva, Cláudio Moisés;Lyra, Roberto Fernando da Fonseca;
Revista Brasileira de Meteorologia , 2009, DOI: 10.1590/S0102-77862009000300009
Abstract: the horizontal wind profiles measured by a sodar and radiosondes during the drytowet-amc/lba experiment are compared. the analysis were made considering three layers: from surface up to 500 m, from 500 up to 1000 m and from 1000 to 1500 m. in the first layer the wind field profiles are in good agreement, however, the correlation values between sodar and radiosonde data, gets significantly lower for the other two layers. the results suggest that the sodar data should better be used if operating from surface up to 500 m and with greater vertical resolution.
Aerossóis, nuvens e clima: resultados do experimento LBA para o estudo de aerossóis e microfísica de nuvens
Costa, Alexandre Araújo;Pauliquevis, Theotonio;
Revista Brasileira de Meteorologia , 2009, DOI: 10.1590/S0102-77862009000200010
Abstract: atmospheric aerosols account for some of the largest uncertainties regarding climate change scenarios. the uncertainties associated to the estimates of the aerosol contributions in the global energy budget is still very high, particularly concerning the so-called "indirect effect". hence, although the level of scientific understanding on the role of aerosols in climate have advanced significantly in the last few years, it is still very low in comparison to the well established knowledge concerning the effect of greenhouse gases. particularly in brazil, the measurements taken during the lba-smocc-emfin! (large-scale biosphere-atmosphere experiment inamazonia - smokeaerosols, clouds, rainfall and climate - experimento de microfísica de nuvens) provided a comprehensive data base on aerosols and cloud microphysics. in this work, we review some of the major results related to such data base, via both analysis of experimental data and numerical modeling. we conclude that significant changes in precipitation development may occur in association with the large amount of aerosols launched into the atmosphere by forest fires but that several questions, especially those ones concerning giant cloud condensation nuclei and ice nuclei, have to be clarified.
Validation of SSiB Model over Grassland with CHeRES Field Experiment Data in 2001
SUN Lan,XUE Yongkang,
SUN Lan
,XUE Yongkang

大气科学进展 , 2004,
Abstract: The Simplified Simple Biosphere model (SSiB) is validated in off-line simulations against field measurements in the summer of 2001 from the China Heavy Rainfall Experiment and Study (CHeRES) over a grassland site located in the lower reaches of the Yangtze River. When initialized and driven by the observed atmospheric forcing, the model reproduced the observed surface heat fluxes and surface skin temperature realistically. The model was also able to well simulate the variation of soil water content. The sensitivity experiments found that the leaf reflectance was the most significant parameter in improving the estimation of surface albedo during both wet and dry periods. This study suggests that the model is capable of simulating the physical processes and of assessing the impact of biophysical parameters that relate to land-atmosphere interactions over the eastern Asian monsoon regions, which is crucial for mesoscale atmospheric models.
陆面模式SSiB耦合TOPMODEL对流域水文模拟影响的数值试验  [PDF]
高原气象 , 2013, DOI: 10.7522/j.issn.1000-0534.2012.00076
Abstract: 为了检验陆面模式SSiB耦合TOPMODEL模型对流域水量平衡模拟结果的影响,用原始SSiB与TOPMODEL按饱和区和非饱和区两种方案耦合的耦合模型(下称SSiBT)进行长江下游青弋江流域水文的数值试验,通过耦合模型与原始SSiB模式模拟结果的比较,并利用流域实测逐日流量和水量平衡资料,揭示了流域水文模拟结果对SSiB耦合TOPMODEL的响应和原因。结果表明:(1)与原始SSiB的模拟结果相比,SSiBT增加了土壤湿度的模拟结果和各层土壤湿度之间的差异,流域蒸散发增加而总径流减小。(2)原始SSiB不能准确地将径流在地表径流和基流之间分配,对于较小的土壤饱和导水率,原始SSiB产生过多的地表径流和洪峰流量;对于较大的土壤饱和导水率又产生过多的基流和明显偏小的洪峰流量。(3)即使土壤饱和导水率大到不会产生超渗产流,由于饱和区的存在,SSiBT在洪水期间也能产生足够大的地表径流,从而形成洪峰流量。由于考虑了地形引起的土壤湿度空间非均匀形成的饱和区产流,SSiBT改善了雨季逐日流量的模拟结果。
VLBI Polarisation with the Yebes (EVN) and Hobart (LBA) antennae  [PDF]
R. Dodson
Physics , 2009,
Abstract: Work has been on-going for the development of the required code for full polarisation processing of VLBI data using some new antennae mounts. The extensions of AIPS allows the support of two new mount types; the left-handed and right-handed Nasmyth antennae (Pico Veleta in the GMVA and Yebes-40m in the EVN) and the EW-mount (Hobart in the LBA). The data handling process is seamless, once the correct mount type has been selected. All subsequent calls to the parallactic angle subroutine PARANG will return the feed angles for Left or Right Nasmyth or EW-mount. These are required, respectively, for Pico Veleta, Yebes-40m (low frequency branch) and Hobart.
农杆菌lba4404不含内源gus基因  [PDF]
徐增富?,李宝健?
生物化学与生物物理进展 , 1996,
Abstract: 用长度为21bp的一对β-葡糖苷酸酶(gus)基因的pcr引物,从根癌农杆菌lba4404细胞总dna中扩增不出任何片段,但从合pbi121的lba4404细胞总dna中可扩增出一条预期大小(1.2kb)的gus基因片段,这表明根瘤农杆菌lba4404不含内源gus基因.
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