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891.
V. I. Domínguez-Rodríguez R. H. Adams-Schroeder J. A. Goñi-Arévalo I. López-Vidal 《International Journal of Environmental Science and Technology》2018,15(9):1851-1858
The chemical–biological stabilization technology has been employed in several successful studies using sugarcane cachasse as the organic amendment. However, in some petroleum-producing areas, there are no sugar mills nearby (which is the source of this material), and the cost of transport to the contaminated site is prohibitive. Therefore, water lily, which is considered a weedy plant in many tropical and subtropical areas, was evaluated as an alternative. In 3-month experiment, water lily was compared (with and without addition of molasses) with cachasse for the treatment of clayey sediment contaminated with > 6% extra-heavy crude oil. All treatments resulted in a reduction in the hydrocarbon concentration of 15–23%, without significant differences (P > 0.05). During this process, the pH was reduced to the 7–7.5 range and water repellency (molarity ethanol drop) to 3.5–3.6 M. Also, field capacity increased to 36.3–38.5% humidity, establishing adequate conditions for the development of vegetation at this site. Likewise, toxicity was reduced to practically null (Vibrio fischeri bioassay), and hydrocarbons in leachates were reduced to 3.4–4.3 mg/l, conditions adequate for the protection of groundwater and human health in rural areas. This study confirms that water lily is an adequate substitute for the application of this treatment method for hydrocarbon-contaminated sites that are far from sugar production areas. 相似文献
892.
Martín Hernández-Marín Lilia Guerrero-Martínez Alfredo Zermeño-Villalobos Lorena Rodríguez-González Thomas J. Burbey Jesús Pacheco-Martínez Sergio I. Martínez-Martínez Norma González-Cervantes 《Hydrogeology Journal》2018,26(8):2811-2826
The investigation involves a temporal and spatial analysis to characterize recharge in the Aguascalientes valley in central Mexico. The results are based on a two-part methodological strategy using a geospatial and numerical analysis. Results from the geospatial analysis are based on the analytical hierarchical process (AHP) method, which involves developing a zoning map that qualifies the conditions for groundwater recharge in the valley. In addition, one-dimensional numerical modeling based on the van Genuchten equation was applied for various soil column configurations to estimate the transit time of recharge through the vadose zone. The analysis was performed over a 20-year period from 1995 to 2015. The results of the geospatial analysis indicate that the optimal area for groundwater recharge is the lower zone of the valley, particularly the portion influenced by surface discontinuities. The shortest estimated period of recharge for water to pass through the vadose zone is approximately 4.25 years. 相似文献
893.
Martínez-Santos P. Castaño-Castaño S. Hernández-Espriú A. 《Hydrogeology Journal》2018,26(4):1083-1097
Hydrogeology Journal - Aquifers provide a reliable freshwater source in arid and semiarid regions, where droughts are common and irrigated crops present significant water requirements, so intensive... 相似文献
894.
Rodríguez-Cañero Rosario Jabaloy-Sánchez Antonio Navas-Parejo Pilar Martín-Algarra Agustín 《International Journal of Earth Sciences》2018,107(5):1791-1806
International Journal of Earth Sciences - Graphite-rich metamorphic limestones included within low-grade black schists of the lowest Nevado-Filábride tectonic unit in the Sierra de Baza... 相似文献
895.
Vázquez R. Macías J. L. Alcalá-Reygosa J. Arce J. L. Jiménez-Haro A. Fernández S. Carlón T. Saucedo R. Sánchez-Núñez J. M. 《Natural Hazards》2022,110(2):1305-1337
Natural Hazards - Both climate and land-use changes can influence drought in different ways. Thus, to predict future drought conditions, hydrological simulations, as an ideal means, can be used to... 相似文献
896.
897.
Regulating migration to Australia and back to the Philippines: Applying a ‘diaspora strategies’ framework
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Justin Peñafiel 《Singapore journal of tropical geography》2015,36(2):201-214
This paper examines circular labour migration between Australia and the Philippines by bringing Australian immigration policies and Philippine diaspora strategies under the same analytical framework. An extensive Philippine bureaucracy regulates migrants at each stage of the circular migration cycle, and as a sending state it has an interest in migrants staying temporarily in host countries such as Australia. The requirement to return home at the end of an overseas work contract compels migrants to remain attached to the sending state, their homeland, and return subsequently. However, Australia is allowing a route for temporary migrants to apply for permanent residency while in the host country. This has implications for sending states that rely on migrant ties to the homeland. The paper argues that analysing the intersections between the themes of migration, development and diaspora strategies reveals the multiple meanings of temporariness during migration and in migration studies. It questions whether associating temporariness with precariousness and marginalization is an accurate representation of the complex conditions underpinning circular labour migration. 相似文献
898.
Abdennour Mohamed Amine Douaoui Abdelkader Barrena Jesús Pulido Manuel Bradaï Abdelhamid Bennacer Amel Piccini Chiara Alfonso-Torreño Alberto 《中国地球化学学报》2021,40(2):234-250
Acta Geochimica - The agriculture in Biskra, southeastern Algeria, is based on traditional practices and characterized by small irrigated fields. In the last decades, the increasing demand in water... 相似文献
899.
Fabian Gutierrez-Aguilar Peter Schaaf Gabriela Solís-Pichardo Gerardo F.Arrieta-García Teodoro Hernandez-Trevino Carlos Linares-Lopez 《地学前缘(英文版)》2021,12(1):293-312
The Yelapa-Chimo Metamorphic Complex forms part of the Jalisco Block in western Mexico and exposes a wide range of Early Cretaceous metamorphic rocks;such as paragneiss,orthogneiss,amphibolites,and migmatites.However,the pressure-temperature(P-T)conditions of metamorphism and partial melting remain poorly studied in the region.To elucidate metamorphic P-T conditions,phase equilibrium modelling was applied to two sillimanite-garnet paragneisses,one amphibole-orthogneiss,and one amphibolite.Sillimanite-garnet paragneisses exhibit a lepidoblastic texture with a biotite+sillimanite+kyanite+garnet+quartz+plagioclase+K-feldspar mineral assemblage.Amphibole-orthogneiss and amphibolite display a nematoblastic texture with an amphibole+(1)plagioclase+quartz+(1)titanite assemblage and an amphibole+(2)plagioclase+(2)titanite+ilmenite retrograde mineral assemblage.Pseudosections calculated for the two sillimanite-garnet paragneiss samples show P-T peak conditions at~6-7.5 kbar and~725-740℃.The results for amphibole-orthogneiss and the amphibolite yield P-T peak conditions at~8.5-10 kbar and~690-710℃.The mode models imply that metasedimentary and metaigneous units can produce up to~20 vol%and~10 vol%of melt,respectively.Modelling within a closed system during isobaric heating suggests that melt compositions of metasedimentary and metaigneous units are likely to have direct implications for the petrogenesis of the Puerto Vallarta Batholith.Our new data indicate that the Yelapa-Chimo Metamorphic Complex evolved through a metamorphic gradient between~23-33℃km^-1and the metamorphic rocks formed at depths between~22 km and~30 km with a burial rate of~2.0 km Ma^-1.Finally,the P-T data for both metasedimentary and metaigneous rocks provide new constraints on an accretionary framework,which is responsible for generating metamorphism and partial melting in the YelapaChimo Metamorphic Complex during the Early Cretaceous. 相似文献
900.
Wang Liang Zhang Xue Zaniboni Filippo Oñate Eugenio Tinti Stefano 《Mathematical Geosciences》2021,53(1):81-103
Mathematical Geosciences - Notwithstanding its complexity in terms of numerical implementation and limitations in coping with problems involving extreme deformation, the finite element method (FEM)... 相似文献