Whole Ecosystem Evidence of Eutrophication Enhancement by Wetland Dredging in a Shallow Tropical Lake     

Humberto Marotta  Luiz Bento  Francisco de A. Esteves  Alex Enrich-Prast 《Estuaries and Coasts》2009,32(4):654-660

The purpose of this research was to assess the effects of dredging performed in a marginal wetland colonized by aquatic macrophytes on eutrophication of the adjacent shallow tropical lake (Imboassica Lake, Brazil). The river mouth of the Imboassica River that drains into Imboassica Lake had been densely colonized by aquatic vegetation dominated by Typha domingensis (Pers.) when it was dredged. Total and dissolved nitrogen and phosphorus concentrations were measured monthly over 13 years at four stations in the Imboassica river-lake system. Dredging activities reduced phosphorus and nitrogen retention at the river mouth and subsequently increased these nutrient stocks in the lake waters. Nutrient retention by non-dredged wetland was estimated to be ca. 1,200 kg year⁻¹ (87.3 g m⁻² year⁻¹) for nitrogen and 60 kg year⁻¹ (4.5 g m⁻² year⁻¹) for phosphorus. Our whole-lake approach suggested that dredging might intensify rather than mitigate eutrophication in shallow tropical lakes when the removal of aquatic macrophytes is coupled to the persistence of anthropogenic nutrient inputs from the watershed.  相似文献   

Erratum to: Downward longwave radiation estimates for clear and all-sky conditions in the Sertãozinho region of São Paulo, Brazil     

Nadiane Smaha Kruk  Íria Fernandes Vendrame  Humberto Ribeiro da Rocha  Sin Chan Chou  Osvaldo Cabral 《Theoretical and Applied Climatology》2010,102(3-4):483-483

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Seismic vulnerability and loss assessment of the Nepalese Pagoda temples     

Manjip Shakya  Humberto Varum  Romeu Vicente  Aníbal Costa 《Bulletin of Earthquake Engineering》2015,13(7):2197-2223

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Climate change predictions for South America     

Juan J. Burgos  Humberto Fuenzalida Ponce  Luiz C. B. Molion 《Climatic change》1991,18(2-3):223-239

Some of the characteristics of predicted climate changes for South America are analysed for the years 2010 and 2050. These predictions are based on the results of three-dimensional Global Circulation Models (GCMs). The results differ between models (GISS, NCAR-CCMs and GFDL), particularly when applied to regional and sub-regional scales and to time scales of less than one-year intervals. It is concluded that these differences are due to the particular structure of each model as well as to the lack of sufficient basic data from the South American sub-continent. The dynamics of vegetation cover play an important role in future water balance changes. The changes in surface temperatures predicted by the GISS model are discussed in relation to changes in the climatic-dynamic base stemming from anthropogenic changes in the vegetation cover.  相似文献   

Analysis of model-based PM2.5 emission factors for on-road mobile sources in Mexico     

M. Zavala  H. Barrera  J. Morante  L.T. Molina 《Atmósfera》2013,26(1):109-124

This study investigates the effects of using the US-EPA MOVES2010a model for estimating PM2.5 emission factors in the Mexican vehicle fleet; the results are compared with the current PM2.5 emissions estimates in the 2005 Mexican National Emissions Inventory (MNEI). Our results show that model-based PM2.5 emissions factors updated from recent studies can have significant impacts on the estimated PM2.5 emissions from mobile sources in Mexico. Higher fractions of older vehicles tend to increase PM2.5 emissions estimates using MOVES2010a with respect to the 2005 MNEI estimates; however, the overall impact on PM emissions varies depending on the vehicle population and vehicle age composition for each Mexican state fleet. These effects are primarily driven by the higher PM2.5 emission factors from the gasoline-powered vehicles and by the high fractions of older gasoline and diesel vehicles. The results also indicate that the estimated MOVES2010a PM2.5 emission factors for Mexico were particularly sensitive to vehicle speed, ambient temperature and sulfur content, but not the relative humidity. There is a strong need to better understand the characteristics of fine particulate matter (PM) emitted from gasoline and diesel-powered vehicles in major urban areas in Mexico.  相似文献   

Preface to special issue on numerical modelling of URM buildings: benchmark project     

Dolce  Mauro  Lagomarsino  Sergio  Varum  Humberto 《Bulletin of Earthquake Engineering》2022,20(4):1897-1900

Bulletin of Earthquake Engineering -  相似文献   

The Surface of Cometary Nulcei Related Minor Icy Bodies     

Javier Licandro  Juan C. Guerra  Humberto Campins  Mario Di Martino  Luisa M. Lara  Ricardo Gil–Hutton  Gian P. Tozzi 《Earth, Moon, and Planets》2002,90(1-4):495-496

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Reproduction and feeding of Sagitta enflata in the Humboldt Current system off Chile     

Giesecke  Ricardo; Gonzalez  Humberto E. 《ICES Journal of Marine Science》2008,65(3):361-370

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Seismic risk assessment for mainland Portugal     

Vitor Silva  Helen Crowley  Humberto Varum  Rui Pinho 《Bulletin of Earthquake Engineering》2015,13(2):429-457

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Development and application of a real-time loss estimation framework for Portugal   总被引：1，自引：0，他引：1  

Vitor Silva  Mário Marques  José Miguel Castro  Humberto Varum 《Bulletin of Earthquake Engineering》2015,13(9):2493-2516

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