Mechanical Behavior of Clayey Soil Reinforced with Recycled Tire Rubber Using Chips and Fibers     

Jaramillo  Natalia Andrea Durán  dos Santos Ferreira  José Wilson  Malko  José Adriano Cardoso  Casagrande  Michéle Dal Toé 《Geotechnical and Geological Engineering》2022,40(6):3365-3378

Geotechnical and Geological Engineering - The volume of discarded tires continues to increase each year, becoming a major topic of concern for society. Motivated by this environmental issue, this...  相似文献   

Petrology and structure of the Palaeoproterozoic (1.9 Ga) Rytky nickel sulphide deposit,Central Finland: a comparison with the Kotalahti nickel deposit     

Jari?M?kinenEmail author  Hannu?V.?Makkonen 《Mineralium Deposita》2004,39(7):793-793

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Comparative measurements and seasonal variations in energy and carbon exchange over forest and pasture in South West Amazonia   总被引：1，自引：0，他引：1  

C. von Randow  A. O. Manzi  B. Kruijt  P. J. de Oliveira  F. B. Zanchi  R. L. Silva  M. G. Hodnett  J. H. C. Gash  J. A. Elbers  M. J. Waterloo  F. L. Cardoso  P. Kabat 《Theoretical and Applied Climatology》2004,78(1-3):5-26

Summary Comparative measurements of radiation flux components and turbulent fluxes of energy and CO₂ are made at two sites in South West Amazonia: one in a tropical forest reserve and one in a pasture. The data were collected from February 1999 to September 2002, as part of the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA). During the dry seasons, although precipitation and specific humidity are greatly reduced, the soil moisture storage profiles down to 3.4m indicate that the forest vegetation continues to withdraw water from deep layers in the soil. For this reason, seasonal changes observed in the energy partition and CO₂ fluxes in the forest are small, compared to the large reductions in evaporation and photosynthesis observed in the pasture. For the radiation balance, the reflected short wave radiation increases by about 55% when changing from forest to pasture. Combined with an increase of 4.7% in long wave radiation loss, this causes an average reduction of 13.3% in net radiation in the pasture, compared to the forest. In the wet season, the evaporative fraction (E/R_n) at the pasture is 17% lower than at the forest. This difference increases to 24% during the dry season. Daytime CO₂ fluxes are 20–28% lower (in absolute values) in the pasture compared to the forest. The night-time respiration in the pasture is also reduced compared to the forest, with averages 44% and 57% lower in the wet and dry seasons, respectively. As the reduction in the nocturnal respiration is larger than the reduction in the daytime uptake, the combined effect is a 19–67% higher daily uptake of CO₂ in the pasture, compared to the forest. This high uptake of CO₂ in the pasture site is not surprising, since the growth of the vegetation is constantly renewed, as the cattle remove the biomass.  相似文献   

Increased Carbon Sink in Temperate and Boreal Forests   总被引：6，自引：0，他引：6  

Jari Liski  Alexander V. Korotkov  Christopher F. L. Prins  Timo Karjalainen  David G. Victor  Pekka E. Kauppi 《Climatic change》2003,61(1-2):89-99

An intense search is under way to identify the `missing sink' in the world carbon budget of perhaps 2 Pg year^–1 (petagrams, or billiontonnes) of carbon, but its location and mechanism have proved elusive. Here we use a new forest inventory data set to estimate the carbon sink and the carbon pool of woody biomass in 55 countries that account for nearly all temperate or boreal forests and approximately half the world's total forest area. In each country there was a net accumulation of biomass; together, the carbon sink of woody biomass was 0.88 Pg year^–1 during the 1990swith estimated uncertainty from 0.71 to 1.1 Pg year^–1. Thisestimate, already about half of the missing sink, would probably be even larger if carbon accumulation in soil and detritus were also accounted for, but we are unable to quantify that additional sink. The sink is twice that estimated for the woody biomass of these forests a decade ago due to higher estimates for tree growth throughout the region and decreased timber harvests in Russia. In contrast, the new data indicate a carbon pool that is smaller than earlier estimates because of improved data for Russia and Australia.  相似文献   

Radon and progeny (Pb and Bi) in urban water-supply systems of São Paulo State,Brazil     

Daniel Marcos Bonotto  Priscilla Cardoso Padron-Armada 《Applied Geochemistry》2008

Many water-supply systems in South America utilize the waters of the Guarani aquifer at least as part of their networks. However, there is little present knowledge in Brazil of the factors affecting Rn presence in the water supplied for end-users, despite the economic importance of Guarani aquifer. ²²²Rn analyzes of 162 water samples were performed at 8 municipalities in São Paulo State, Brazil, with the aim of investigating the major factors affecting its presence in solution. The ²²²Rn activity concentration ranged from 0.04 up to 204.9 Bq/L, with three samples exceeding the World Health Organization maximum limit of 100 Bq/L. Aeration was confirmed as the most important factor for Rn release, as expected due to its gaseous nature. Accumulation in pipes and stratification in the water column were other significant factors explaining the data obtained in some circumstances. The Rn daughters ²¹⁴Pb and ²¹⁴Bi were also determined in a set of selected samples and their presence was directly related to the occurrence of Rn dissolved in water.  相似文献   

Reducing the grid orientation dependence of flow routing on square-grid digital elevation models   总被引：1，自引：0，他引：1  

Jari Hyväluoma 《International journal of geographical information science》2017,31(11):2272-2285

Topographical parameters derived from digital elevation models by employing flow routing algorithms may depend on the orientation of the square grid. Grid orientation dependence results from the insufficient isotropy of square grid and affects the flow directions and subsequent calculations based on flow routing. In this article, a systematic approach for analysing the rotational invariance of flow accumulation calculations is presented and applied. Computed flow accumulation maps are found to depend strongly on the grid orientation, especially if flow routing methods with low dispersion are used. It is also shown that isotropy of flow routing algorithms can be significantly improved by introducing a numerical parameter resulting in adjustable weighting for cardinal and diagonal directions in flow routing. The actual value of this parameter depends on the used flow routing method.  相似文献   

Sources and transport of lipids on Amazon continental shelf     

Vladimir O. Elias  Jari N. Cardoso 《Geo-Marine Letters》1996,16(1):11-16

Dissolved material and recent sediment from the Amazon continental shelf have been analyzed for hydrocarbons to study the sources and potential fate of the transported organic matter. Dissolvedn-alkanes are present at low concentrations (ppb level) and are dominated by lipids from marine phytoplankton with carbon number maxima (C_max) at C₁₈/C₂₂ and an even-to-odd carbon predominance < C₃₀ (CPI_17–27 from 0.18 to 0.54). In the sediments, bimodal distributions ofn-alkane chain length suggest a mixed input of terrestrial (C_max at C₂₇/C₂₉/C₃₁ and CPI_25–33 from 0.75 to 1.82) and phytoplanktonic/microbial (C_max at C₂₀ and CPI_15–25 from 0.38 to 0.62) organic matter. Sesquiterpenes were the most significant cyclic compounds in all the dissolved samples analyzed reflecting a contribution from resinous trees to the terrestrial organic pool. On the other hand, enhanced concentrations of these compounds in the dissolved phase on the northwest portion of the Amazon shelf, contrasting with decreased concentrations in the sediment samples, suggest that dissolved lipids are released from solid phase in the intensely stirred seabed. Structured organic matter in the sediment has been characterized as being composed of, on average: 19% plant cuticles, 25% woody tissue, 13% pollens and spores, 24% amorphous material, 7% bituminite and 12% altered organic material.  相似文献   

The use of hydroxyacids as geochemical indicators     

J.N. Cardoso  G. Eglinton 《Geochimica et cosmochimica acta》1983,47(4):723-730

The distributions of hydroxyacids in a variety of Recent and ancient sediments have been determined by gas chromatography-mass spectrometry. A lacustrine sediment (Rostherne Mere, U.K.) and two marine situations (Cariaco Trench, Black Sea) were analyzed as examples of Recent depositional environments. β-hydroxyacids occurred in all of the Recent sediments, consistent with their presumed microbial origin, whereas di- and trihydroxyacids were present in the sediments with a significant higher plant input (Black Sea and Rostherne Mere sediments). The two ancient (Eocene) sediments examined, viz. the Greene River (U.S.) and Messel (Germany) oil-shales, contained only trace amounts of hydroxyacids. These results provide evidence that hydroxyacids are in general not well preserved over geological time.  相似文献   

The first multi-model ensemble of regional climate simulations at kilometer-scale resolution part 2: historical and future simulations of precipitation     

Pichelli  Emanuela  Coppola  Erika  Sobolowski  Stefan  Ban  Nikolina  Giorgi  Filippo  Stocchi  Paolo  Alias  Antoinette  Belu&#;i&#;  Danijel  Berthou  Segolene  Caillaud  Cecile  Cardoso  Rita M.  Chan  Steven  Christensen  Ole B&#;ssing  Dobler  Andreas  de Vries  Hylke  Goergen  Klaus  Kendon  Elizabeth J.  Keuler  Klaus  Lenderink  Geert  Lorenz  Torge  Mishra  Aditya N.  Panitz  Hans-Juergen  Sch&#;r  Christoph  Soares  Pedro M. M.  Truhetz  Heimo  Vergara-Temprado  Jesus 《Climate Dynamics》2021,56(11):3581-3602

This paper presents the first multi-model ensemble of 10-year, “convection-permitting” kilometer-scale regional climate model (RCM) scenario simulations downscaled from selected CMIP5 GCM projections for historical and end of century time slices. The technique is to first downscale the CMIP5 GCM projections to an intermediate 12–15 km resolution grid using RCMs, and then use these fields to downscale further to the kilometer scale. The aim of the paper is to provide an overview of the representation of the precipitation characteristics and their projected changes over the greater Alpine domain within a Coordinated Regional Climate Downscaling Experiment Flagship Pilot Study and the European Climate Prediction system project, tasked with investigating convective processes at the kilometer scale. An ensemble of 12 simulations performed by different research groups around Europe is analyzed. The simulations are evaluated through comparison with high resolution observations while the complementary ensemble of 12 km resolution driving models is used as a benchmark to evaluate the added value of the convection-permitting ensemble. The results show that the kilometer-scale ensemble is able to improve the representation of fine scale details of mean daily, wet-day/hour frequency, wet-day/hour intensity and heavy precipitation on a seasonal scale, reducing uncertainty over some regions. It also improves the representation of the summer diurnal cycle, showing more realistic onset and peak of convection. The kilometer-scale ensemble refines and enhances the projected patterns of change from the coarser resolution simulations and even modifies the sign of the precipitation intensity change and heavy precipitation over some regions. The convection permitting simulations also show larger changes for all indices over the diurnal cycle, also suggesting a change in the duration of convection over some regions. A larger positive change of frequency of heavy to severe precipitation is found. The results are encouraging towards the use of convection-permitting model ensembles to produce robust assessments of the local impacts of future climate change.

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Future surface temperature changes for the Iberian Peninsula according to EURO-CORDEX climate projections     

Carvalho  D.  Cardoso Pereira  S.  Rocha  A. 《Climate Dynamics》2021,56(1-2):123-138

Climate Dynamics - Future changes in the mean, maximum and minimum temperature in the Iberian Peninsula were investigated using bias-corrected EURO-CORDEX climate projections. The results show that...  相似文献