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1.
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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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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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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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   
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In this article, we estimated the alpha parameter of the Priestley–Taylor model under rain‐fed conditions. This study was conducted in an oat crop, from 7 September to 22 October 2009, in a region of subhumid plains (Tandil, Argentina). An energy balance station was installed within the experimental field to monitor its development. The alpha parameter value obtained was 1.41 ± 0.01, which led to an overestimation of the evapotranspiration of just 2% and a relative error in estimating evapotranspiration of 8%. The results suggest that the alpha parameter obtained is adequate in estimating the evapotranspiration of oat crops or similar crops in subhumid plains of Buenos Aires, Argentina. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
9.
Montaña Pelada is a basaltic Pleistocene tuff ring located in the SE of Tenerife and it is composed of two edifices each with its distinct internal depositional distribution. A detailed stratigraphic analysis was carried out and ten facies were recognized. Deposits interpretation has revealed that water/magma ratio changes controlled the eruptive evolution, distinguishing three main stages of the eruption. Pyroclastic density currents were formed during the initial phreatomagmatic stages depositing the proximal facies, and transformed into turbulent dry surges during the second stage, indicating a reduction in the water/magma ratio. After deposition of these surges, the opening of an N–S fracture drove the eruption northwards creating a new edifice. The new hydrological conditions allowed the input of phreatic water, which resulted in high proportion of accidental lithics within characteristic of the deposits, increasing the water/magma ratio and reducing the fragmentation degree as can be recognized in the third stage. The evolution of the second tuff was similar, starting with radial-diluted pyroclastic surges and finishing with base surges deposits, suggesting lower water/magma ratio and higher fragmentation degree. Whereas the south cone originates dry pyroclastic surges and many tuff facies, northern one does not go beyond the deposition of a laminated tuff.  相似文献   
10.
The site of Pauli Stincus is located near the town of Terralba, on the inland shores of the Gulf of Oristano in west central Sardinia, Italy, and was occupied between the mid‐4th and the late 2nd century B.C. The site and its surroundings were the object of a joint archaeopedological and geomorphological study, which complemented the data from archaeological excavations. This study allowed us to evaluate the suitability of the different landscape and soil components for crop production in the Punic period. The discovery of a buried plow soil at the site's edge enabled us to identify a set of agricultural practices carried out by Punic farmers. These included the removal of sandy topsoil to cultivate deeper horizons enriched in illuvial clay, the use of a "sodbuster" or "rip ard," and the periodic burning of weeds, stubble, and other harvesting residues. The present study helped us to better understand the formation processes of the archaeological record at Pauli Stincus. Large quantities of allochtonous calcareous material were imported to the site from wet areas closer to the coast in order to produce earth‐based construction material, such as bricks and daub. © 2013 Wiley Periodicals, Inc.  相似文献   
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