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Jehad Mahmoud Hussein Ighbareyeh Eusebio Cano Carmona Ana Cano Ortiz Asma Abdel-Rahim Ahmed Suliemieh Mohammed Mahmoud Hussein Ighbareyeh Abed Al-Qader Mohammed Daraweesh 《Arabian Journal of Geosciences》2018,11(21):683
For the 1993–2009 period, we analyzed the relationship between almond yield and three climatic variables (mean annual temperature, soil water reserve, and precipitation), and four bioclimatic variables (annual ombrothermic index, water deficit, simple continentality index, and compensated thermicity index), for one major Hebron crop (soft and hard almonds). Moreover, we obtained data almond production from the Palestinian Central Bureau of Statistics, while the climate data from the Palestinian meteorological station during the study period from 1993 to 2009, and analysis is it by using bioclimatic classification of the Earth of Salvador Rivas-Martinez to study the relationship between the almond yield and climate and bioclimate factors (variables). The climatic and bioclimate variables of greatest importance to almond were used to develop regressions analysis relating yield to climatic conditions. Hebron was positively affected by annual ombrothermic index, simple continentality index, precipitation, water soil reserve, and mean annual temperature, but negatively affected by water deficit, with a large proportion of the variance explained by axis F1 (72.48%), F2 (22.38%), and axes F1and F2 (94. 86%). However, in order to produce a high amount of almonds and quality, it can be grown in the regions of the mesomediterranean region, with the value of annual ombrothemic index more than 3, compensated thermicity index between 220/220 to 350/350, simple continentality index between 14 and 20, and in areas where the average annual temperature is between 15 and 20 °C. 相似文献
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Surveys in Geophysics - Deception Island is an active volcano located in the South Shetland Islands, Antarctica. Although the last eruptions occurred in 1967-1970, the volcano has undergone periods... 相似文献
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Jofre Herrero Diana Puigserver Beth L. Parker José M. Carmona 《Ground Water Monitoring & Remediation》2021,41(3):51-57
A new method for the extraction of chlorinated solvents (CSs) from porewater with dimethylacetamide (DMA) used as a solvent and the determination of δ13C by gas chromatography-isotope ratio mass spectrometry (GC-IRMS) with solid-phase microextraction (SPME) are presented. This method was used for the determination of δ13C of chloroethenes and chloromethanes. The extraction of the CSs from porewater with DMA led to a minimal loss of mass of solvent and chlorinated compounds. The accuracy of the method was verified with the analysis of the pure injected compounds using elemental analyzer—isotope ratio mass spectrometry (EA-IRMS). It has been effectively applied in a study area in saturated soil samples of a pollutant source zone of perchloroethylene (PCE) and trichloroethylene (TCE). The limit of quantification of the new method was 0.034 μg/g for PCE and TCE for 10–20 g of soil sample. This new method allows for compound-specific isotope analysis of CSs in porewater, which can be beneficial in sites where the identification of contamination sources and the behavior of the contaminants are not clear. 相似文献
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Noelia?Liliana?AlchaparEmail author Claudia?Cotrim?Pezzuto Erica?Norma?Correa Lucila?Chebel Labaki 《Theoretical and Applied Climatology》2017,130(1-2):35-50
This paper describes different ways of reducing urban air temperature and their results in two cities: Campinas, Brazil—a warm temperate climate with a dry winter and hot summer (Cwa), and Mendoza, Argentina—a desert climate with cold steppe (BWk). A high-resolution microclimate modeling system—ENVI-met 3.1—was used to evaluate the thermal performance of an urban canyon in each city. A total of 18 scenarios were simulated including changes in the surface albedo, vegetation percentage, and the H/W aspect ratio of the urban canyons. These results revealed the same trend in behavior for each of the combinations of strategies evaluated in both cities. Nevertheless, these strategies produce a greater temperature reduction in the warm temperate climate (Cwa). Increasing the vegetation percentage reduces air temperatures and mean radiant temperatures in all scenarios. In addition, there is a greater decrease of urban temperature with the vegetation increase when the H/W aspect ratio is lower. Also, applying low albedo on vertical surfaces and high albedo on horizontal surfaces is successful in reducing air temperatures without raising the mean radiant temperature. The best combination of strategies—60 % of vegetation, low albedos on walls and high albedos on pavements and roofs, and 1.5 H/W—could reduce air temperatures up to 6.4 °C in Campinas and 3.5 °C in Mendoza. 相似文献
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Roger Clavera-Gispert Òscar Gratacós Ana Carmona Raimon Tolosana-Delgado 《Computational Geosciences》2017,21(3):373-391
Nowadays, numerical modeling is a common tool used in the study of sedimentary basins, since it allows to quantify the processes simulated and to determine interactions among them. One of such programs is SIMSAFADIM-CLASTIC, a 3D forward-model process-based code to simulate the sedimentation in a marine basin at a geological time scale. It models the fluid flow, siliciclastic transport and sedimentation, and carbonate production. In this article, we present the last improvements in the carbonate production model, in particular about the usage of Generalized Lotka-Volterra equations that include logistic growth and interaction among species. Logistic growth is constrained by environmental parameters such as water depth, energy of the medium, and depositional profile. The environmental parameters are converted to factors and combined into one single environmental value to model the evolution of species. The interaction among species is quantified using the community matrix that captures the beneficial or detrimental effects of the presence of each species on the other. A theoretical example of a carbonate ramp is computed to show the interaction among carbonate and siliciclastic sediment, the effect of environmental parameters to the modeled species associations, and the interaction among these species associations. The distribution of the modeled species associations in the theoretical example presented is compared with the carbonate Oligocene-Miocene Asmari Formation in Iran and the Miocene Ragusa Platform in Italy. 相似文献
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Analía V. Serra Sandra E. Botté Diana G. Cuadrado Noelia S. La Colla Vanesa L. Negrin 《Environmental Earth Sciences》2017,76(6):254
In this study, we measured the concentrations of metals (Cd, Cu, Pb, Ni, Cr, Zn, Hg, Mn, and Fe) and assessed the characteristics of tidal flats (grain size and organic matter content) in sediments and their overlying microbial mats fractions to evaluate the anthropogenic impact within the Bahía Blanca Estuary (BBE). Puerto Rosales (PR) and Almirante Brown (AB), located in the middle and inner zone of the estuary, respectively, were used as sampling sites. Sediments were composed mainly of silt–clay in AB, whereas first fine-grained particles were coarser in depth in PR. Regarding the concentration of metals in both fractions, we found differences between sites: There were higher concentrations of overall metals in AB relative to PR. In addition, higher concentrations of Cu were recorded in the first centimeters of AB tidal flats, whereas higher concentration of Cd were recorded in microbial mats of PR. Considering that the grain size was similar between sites, these results are consistent with the high concentration of organic matter found in AB, probably because this site is close to a former municipal dump and sewage discharges. Also, the higher Cd content found in PR site would highlight both the influence of untreated urban discharges and port anthropogenic activities. In conclusion, this study allowed identifying high values of some metals in the presence of microbial mats in the BBE, thus suggesting a possible interaction between both, at least for metals like Cu or Cd. 相似文献
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This paper presents a new structural-stratigraphic approach to constrain the reservoir potential of the middle Miocene turbidite systems within the Monagas Fold-Thrust Belt (MFTB) and Maturín Sub-Basin (MSB) of eastern Venezuela. In the frontal anticline structures of the MFTB (Amarilis Area) light hydrocarbons have been produced from these turbidite systems which were deposited in a foreland basin with a complex tectonostratigraphic evolution.In order to predict the location of other analogous reservoirs we used the structural model presented in Part I (Parra et al., 2010) to developed a palaeo-topographic reconstruction at early-middle Miocene. We have then used this reconstruction to constrain the palaeogeography of the middle Miocene foredeep where the turbidites were deposited. The area considered has 5000 km2.By middle Miocene four regions are identified: 1) The southern basin margin dipped 1.5-2.5° north; 2) The foredeep axis had a southwest-northeast orientation. Within the foredeep the proto-structures of the MFTB created submerged highs that control the distribution of sediments; 3) The northern basin margin dipped 3-4° south; the coastline was controlled by the Pirital thrust sheet; 4) The main source of sediments was located towards the northwest on the Pirital thrust sheet and Serranía del Interior.Variations in shortening across the strike of the Pirital thrust were accommodated by a lateral ramp which controlled the location of a valley that acted as the main sediment pathway for the sediments that fed the turbidite system. This relationship between the thrust belt geomorphology and the location of turbidite sediment within the foredeep must be considered in order to assess the distribution of the Miocene turbidite reservoirs. 相似文献
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Roberto Ventura Santos Edilton J. dos Santos João Adauto de Souza Neto Luis Christian Montreuil Carmona Alcides Nóbrega Sial Luis Henrique Mancini Lauro Cézar Montefalco de Lira Santos Gilzênia Henrique do Nascimento Lucas UpaDafubigin Santos Mendes Emerson Marcello Ferreira Anastácio 《Gondwana Research》2013,23(1):380-389
Strongly-deformed marbles may be easily confused with linear and elongated carbonatite intrusions. Both rocks may present similar texture and foliation to the host rock, or even cross cutting field relationships, which could be interpreted either as igneous or high-grade metamorphosed marble. Diagnostic criteria are even more complex when there is evidence of melting of the metasedimentary carbonate rock, such as has been described in the Himalayas and in the Eastern Ghats, India.In the Alto Moxotó Terrane, a high-grade gneissic domain of the Borborema Province, Northeastern Brazil, there are metacarbonates associated with banded gneisses and different metaplutonic rocks. Field evidence indicates the absence of other metasedimentary rocks associated with these marbles, thus suggesting that these carbonates were separated from other siliciclastic metasedimentary rocks. The presence of marble also suggests that it may represent the initial stage of a crustal carbon recycling into the mantle. These marbles present many field similarities to carbonatites (e.g., fluid-flow structure) and, together with metagranites and metamafic intrusions, may represent a major collisional tectonic suture.A detailed study of the carbon, oxygen and strontium isotopic composition of these marbles is presented. This study aims to identify the origin of the different isotopic components. It is argued that these rocks were subjected to temperature and pressure conditions that were sufficiently high to have melted them. The isotopic data presented here support this interpretation and indicate the mixing of two components: (i) one characterized by radiogenic Sr isotopes and mantle-like carbon isotopes, which is associated with the gneissic and mafic rocks, and (ii) another characterized by low 87Sr/86Sr ratios and highly positive δ13C values. Available geochemical data for the upper Paleoproterozoic indicate that the 87Sr/86Sr ratio of ocean water, varying between 0.7050 (2.25 ± 0.25 Ga) and 0.7047 (1.91 Ga), falls within the lower range of the samples from Itatuba and thus reinforces the interpretation that these marbles are sedimentary-derived and were partially contaminated by interaction with the host gneissic and mafic rocks. 相似文献