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Between plaza and peak: a montological perspective on verticality and urbanization in highland Peru

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Journal of Mountain Science 2023年第10期20卷 2783-2803页

作者： Andreas HALLER Domenico BRANCA Deyvis CANO Institute for Interdisciplinary Mountain Research Austrian Academy of SciencesInnsbruck 6020Austria Department of Humanities and Social Sciences University of SassariSassari 07100Italy Programa Académico de ingeniería ambiental Universidad de HuánucoHudnuco 10001Peru

Under the influence of concentrated and extended urbanization,Andean cities and the different altitudinal zones of their“hinterlands”are experiencing profound changes in land cover—from the central plazas up to the highest peaks.The complex regional-geographic characteristics of these socioecological systems,such as the vertical complementarity of land use,require a montological perspective on verticality and urbanization:it transcends disciplinary approaches and can be crucial to properly interpret the trajectories of land cover change and formulate hypotheses for future practiceoriented research.Which trajectories of land cover change characterized altitudinal zones of Andean cities and their surroundings over the last three decades?Are there similarities that allow for the formulation of more general hypotheses?Using the Peruvian cases of Cusco and Huaraz,and combining a traditional altitudinal zonation model of land use in Peru with direct field observations and GIS-based analyses of remotely sensed data from 1991,2001,2011,and 2021,this study identifies the main trajectories of land cover change in the Quechua(>2300–3500 m),Suni(>3500–4000 m),and Puna(>4000–4800 m)regions—and finds insightful similarities between Cusco and Huaraz:(1)an impressive area of built-up land substitutes grassland in the Quechua,which,following regional altitudinal zonation models,is characterized by irrigated and rain-fed cropland;(2)an unexpected expansion of irrigated cropland takes place in the Suni,which,in theory,often lacks irrigation infrastructure and is mostly used for rain-fed tuber cultivation;and(3)a clear change from“other land”to grassland occurs in the Puna—where grassland is thought to predominate,anyway,since pre-Hispanic times.Hypothesizing that these changes reflect the interplay between speculative fallow,agricultural intensification,and ecological restoration,the results can be read as vertically complementary,local manifestations of concentrated and extended urbanization in a formerly peripheral mountain regio

关键词： Mountain cities Mountain agriculture Land use change Land cover change Rural-urban linkages Montology

Modelling fuel loads of understorey vegetation and forest floor components in pine stands in NW Spain

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Forest Ecosystems 2022年第6期9卷 775-789页

作者： Jose A.Vega Stefano Arellano-Perez Juan Gabriel Alvarez-Gonzalez Cristina Fernandez Enrique Jimenez Pedro Cuinas Jose María Fernandez-Alonso Daniel J.Vega-Nieva Fernando Castedo-Dorado Cecilia Alonso-Rego Teresa Fontúrbel Ana Daría Ruiz-Gonzalez Centro de Investigacion Forestal de Lourizan PO Box 12736080PontevedraSpain Unidad de Gestion ambiental y Forestal Sostenible(UXAFORES) Departamento de Ingeniería AgroforestalEscuela Politecnica Superior de IngenieríaUniversidad de Santiago de CompostelaCampus Universitario s/n27002LugoSpain Facultad de Ciencias Forestales Universidad Juarez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120DurangoMexico Departamento de ingeniería y Ciencias Agrarias Universidad de LeonCampus de Ponferrada24401PonferradaSpain

In this study,310 destructively sampled plots were used to develop two equation systems for the three main pine species in NW Spain(P.pinaster;P.radiata and P.sylvestris):one for estimating loads of understorey fuel components by size and condition(live and dead)and another one for forest floor fuels.Additive systems of equations were simultaneously fitted for estimating fuel loads using overstorey,understorey and forest floor variables as regressors.The systems of equations included both the effect of pine species and the effect of understorey compositions dominated by ferns-brambles or by woody species,due to their obvious structural and physiological differences.In general,the goodness-of-fit statistics indicated that the estimates were reasonably robust and accurate for all of the fuel fractions.The best results were obtained for total understorey vegetation,total forest floor and raw humus fuel loads,with more than 76%of the observed variability explained,whereas the poorest results were obtained for coarse fuel loads of understory vegetation with a 53%of observed variability explained.To reduce the overall costs associated with the field inventories necessary for operational use of the models,the additive systems were fitted again using only overstorey variables as potential regressors.Only relationships for fine(<6 mm)and total understorey vegetation and total forest floor fuel loads were obtained,indicating the complexity of the forest overstorey-understorey and overstorey-forest floor relationships.Nevertheless,these models explained around 52%of the observed variability.Finally,equations estimating the total understorey vegetation and the total forest floor fuel loads based only on canopy cover were fitted.These models explained only 26%-32%of the observed variability;however,their main advantage is that although understorey vegetation in forested landscapes is largely invisible to remote sensing,canopy cover can be estimated with moderate accuracy,allowing for landscape-scale estimates of total fuel lo

关键词： Area-based approach Additive equation systems Live and dead fine fuel Pinus pinaster Pinus radiata Pinus sylvestris

Use of two-surfactants mixtures to attain specific HLB values for assisted TPH-diesel biodegradation

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Journal of Environmental Sciences 2004年第6期16卷 950-956页

作者： Luis G. Torres Neftalí Rojas Rosario Iturbe Instituto de ingeniería Universidad Nacional Autó noma de México Coordinación de Ingeniería Ambiental Grupo Saneamiento de Suelos y Acuíferos Apartado Postal 70-472 Coyoacán 04510 México D.F. Mexico.Instituto de Ingeniería Universidad Nacional Autó noma de México Coordinación de Ingeniería Ambiental Grupo Saneamiento de Suelos y Acuíferos Apartado Postal 70-472 Coyoacán 04510 México D.F. Mexico. Instituto de Ingeniería Universidad Nacional Autó noma de México Coordinación de Ingeniería Ambiental Grupo Saneamiento de Suelos y Acuíferos Apartado Postal 70-472 Coyoacán 04510 México D.F. Mexico.

In a surfactant assisted biodegradation process, the choice of surfactant(s) is of crucial importance. The question is: does the type of surfactant(i.e. chemical family) affect the biodegradation process at fixed hidrophillic-lypofillic balance(HLB) values? Microcosm assessments were developed using contaminated soil, with around of 5000 mg/kg of hydrocarbons as TPH-diesel. Mixtures of three nonionic surfactants were employed to get a wide range of specific HLB values. Tween20 and Span20 were mixed in the appropriate proportions to get HLB values between 8.6 and 16.7. Tween/Span60 mixtures reached HLB values between 4.7 and 14.9. Finally, Tween/Span80 combinations yielded HLB values between 4.3 and 15. TPH-diesel biodegradation was measured at the beginning, and after 8 weeks, as well as the FCU/gr soil, as a measure of microorganisms′ development during the biodegradation period. A second aim of this work was to assess the use of guar gum as a biodegradation enhancer instead of synthetic products. The conclusions of this work are that surfactant chemical family, and not only the HLB value clearly affects the assisted biodegradation rate. Surfactant's synergism was clearly observed. Regarding the use of guar gum, no biodegradation enhancement was observed for the three assessed concentrations, i.e., 2, 20, and 200 mg/kg, respectively. On the contrary, TPH-diesel removal was lower as the gum concentration increased. It is quite possible that guar gum was used as a microbial substrate.

关键词： aged soils enhanced bioremediation HLB mixtures Tween Span surfactants

Adsorbents Derived from Xylan Hemicellulose with Removal Properties of Pollutant Metals

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Chinese Journal of Polymer Science 2023年第6期41卷 874-886,I0007页

作者： Elizabeth Elgueta Yerko Becerra Ana Martínez Miguel Pereira Isabel Carrillo-Varela Felipe Sanhueza Dariela Nuez BernabéL.Rivas Centro de Investigación de Polímeros Avanzados CIPAAvenida Collao 1202Edificio de LaboratoriosConcepcionChile Departamento de Química ambiental Facultad de CienciasUniversidad Católica de la Santísima ConcepciónCaila 160-cConcepcionChile Polymer Department Faculty of ChemistryUniversity of ConcepciónCasilla 160-CConcepcionChile Departamento de ingeniería Química Facultad de IngenieríaUniversidad de ConcepciónConcepcionChile Department of Materials Engineering Faculty of EngineeringUniversidad de ConcepciónConcepcionChile

The adsorption capacity of hydrogels derived from modified xylan hemicellulose has been tested in order to develop new bio-based adsorbent materials useful for removing metal ions pollutants,such as Cd(Ⅱ),Cu(Ⅱ)and Pb(Ⅱ)from an aqueous solution.Xylan was extracted from bleached kraft pulp of eucalyptus and subsequently modified with different proportions of functional sulfonic acid groups(HA3-HA7)and sulfonate groups(HS30-HS70)to generate hydrogels.The results showed that all the synthesized hydrogels were capable of adsorbing metal ions,being the hydrogels with 30%and 50%xylan the ones that presented the highest adsorption capacity.Maximum capacity studies at different initial concentrations revealed that at an initial concentration of 300 mg·L-1,the HA3 hydrogel presented an adsorption capacity of 193mg Pb(Ⅱ),182 mg Cd(Ⅱ),and 66 mg Cu(Ⅱ)per g hydrogel.The HA5 hydrogel presented a capacity of 185 mg Pb(Ⅱ),113 mg Cd(Ⅱ),and 48 mg Cu(Ⅱ)per g hydrogel.The HS30 hydrogel exhibited an adsorption of 205 mg Pb(Ⅱ),174 mg Cd(Ⅱ),and 71 mg Cu(Ⅱ)per g hydrogel,and HS50 hydrogel exhibited an adsorption capacity of 273 mg Pb(Ⅱ),143 mg Cd(Ⅱ),and 45 mg Cu(Ⅱ)per g hydrogel.These results show that modified Xylan hemicellulose is a promising adsorbent for removal Cd(Ⅱ),Cu(Ⅱ),and Pb(Ⅱ)ions from aqueous solutions.

关键词： Pb(Ⅱ) solution capacity

Physical and chemical characterization of sediments from an Andean river exposed to mining and agricultural activities: The Moquegua River, Peru

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International Journal of Sediment Research 2022年第6期37卷 780-793页

作者： Luis de Los Santos Valladares Juan Luis Ccamapaza Renato Arturo Valencia-Bedregal Luis Enrique Borja-Castro Jose Velazquez-Garcia Dehiwalage Harshani Nimalika Perera Adrian Ionescu David Arvidsson Eustace Peregrine Barnes Peter Newton Hugo Lepage Patrick Byrne Angel Guillermo Bustamante Dominguez Crispin H.W.Barnes Cavendish Laboratory Department of Physics University of Cambridge Escuela Acad emico Profesional de ingeniería ambiental Universidad Nacional de Moquegua Provincia de Mariscal Nieto Laboratorio de Cer amicos y Nanomateriales Facultad de Ciencias Físicas Universidad Nacional Mayor de San Marcos School of Biological and Environmental Science Liverpool John Moores University

This study presents an analysis of sediments in an Andean river impacted by both natural conditions and anthropogenic activities. Fifty samples were collected from selected sites throughout the Moquegua River drainage basin, and Tambo River headwaters at Pasto Grande, in Peru, and analysed with X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy and thermogravimetric analysis. Si, Ca, Al, Fe, and O, common constituents of soils, were dominant, along with K, N, and P. The latter originating as primary macronutrients or chemical residuals from fertilizers used in agriculture. Higher concentrations of macronutrients and organic components were found in agricultural and urban areas, respectively. Arsenic minerals were also detected, which occur naturally, but possibly at levels augmented by anthropogenic activity. The application of cluster analysis revealed clustering between arsenic, arsenolite, and potassium but no significant geospatial correlation between sample sites in the drainage basin.

关键词： Andean river Moquegua river Sediments Fourier-transform infrared spectroscopy TG-DTG/DTA Clustering analysis

Effective Interaction Force between an Electric Charge and a Magnetic Dipole and Locality (or Nonlocality) in Quantum Effects of the Aharonov–Bohm Type

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Chinese Physics Letters 2021年第3期38卷 39-43页

作者： Gianfranco Spavieri George T.Gillies Miguel Rodriguez Maribel Perez Centro de Física Fundamental Facultad de CienciasUniversidad de Los AndesMérida 5101Venezuela Department of Mechanical and Aerospace Engineering University of VirginiaCharlottesvilleVA 22904USA Departamento de Física Facultad de Ciencia y TecnologíaUniversidad de CaraboboNaguanagua 2001Venezuela Carrera de ingeniería ambiental Facultad de IngenieríaUniversidad Nacional de ChimborazoRiobamba 100150Ecuador

Classical electrodynamics foresees that the effective interaction force between a moving charge and a magnetic dipole is modified by the time-varying total momentum of the interaction fields. We derive the equations of motion of the particles from the total stress-energy tensor, assuming the validity of Maxwell’s equations and the total momentum conservation law. Applications to the effects of Aharonov–Bohm type show that the observed phase shift may be due to the relative lag between interfering particles caused by the effective local force.

关键词： force. momentum interaction

Analysis of the Relation between Particle Matter Concentration and Meteorological Parameter at Montevideo City

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Open Journal of Air Pollution 2018年第2期7卷 120-139页

作者： José Cataldo Alice Elizabeth González Instituto de Mecánica de los Fluidos e ingeniería ambiental Facultad de Ingeniería Universidad de la RepúblicaMontevideo Uruguay

We present an analysis of particle matter (MP) concentration measured at three stations located in the department of Montevideo, Uruguay. The Montevideo Council and the National Directorate of the Environment of Uruguay are interested in analyzing the possibility of predicting unsettling air quality events by other means not directly related to build and operate a real time air quality monitoring network. A strong correlation between measurements in different air quality stations especially along events of high concentration was obtained;it is intended to be associated with a distributed source. In such cases, high correlation was also found between the pollutant concentration and the meteorological variables temperature, wind velocity and mixing layer depth. As there is no air quality available data in real time, an accurate prediction of meteorological variables seems to be a good option for properly forecasting of air quality in Montevideo city, especially in terms of MP concentrations.

关键词： Air Quality Particle Matter Pollution Atmospheric Boundary Layer

The largest dengue outbreak in Argentina and spatial analyses of dengue cases in relation to a control program in a district with sylvan and urban environments

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Asian Pacific Journal of Tropical Medicine 2018年第3期11卷 227-234页

作者： Aníbal E Carbajo Alejandra Rubio María J Viani María R Colombo Laboratorio de Eoclogía de Enfermedades Transmitidas por Vectores Instituto de Investigación e Ingeniería AmbientalUniversidad Nacional de General San Martín Consejo Nacional de Investigaciones Científicas y Técnicas Secretaria de Política Sanitaria y Desarrollo Humano Municipio de Tigre

Objective: To analyze the largest outbreak of dengue in Argentina in the municipality of Tigre during 2016, through detailed spatial analyses of the occurrence of cases in relation to demographic factors and vector control actions. Methods: Detailed and georreferenced data on dengue cases with laboratory results(NS1 or IgM) were analyzed. The occurrences of imported and autochthonous cases by census tract were modeled using demographic variables(population by age class, proportion of foreigners, proportion with university grade, proportion of males), dwelling variables(number of homes, proportion of dwellings with latrine, number of dwellings, proportion of houses, proportion of flats, proportion of slums) and census tract area as explanatory variables. The probability of occurrence of autochthonous and imported cases was modeled separately. The spatio-temporal occurrence of cases was studied in relation to focal and perifocal control actions(involving education campaigns, removal of Aedes aegypti breeding sites and exhaustive insecticide spraying) to assess the efficiency in stopping autochthonous cases spreading. Results: All autochthonous cases occurred in the urban environment with no sylvan cases. The majority of the imported cases registered came from Paraguay and Northeastern Argentina. The age structure of imported and autochthonous cases did not differ from the age structure of the municipality, while that of the negative cases did.When studied spatially, the occurrence of imported cases by census tract was mildly associated with a higher proportion of foreign population and more people at active age, while occurrence of autochthonous cases was not significantly associated with any of the studied variables.For census tracts with laboratory confirmed results, the models showed higher probability of autochthonous cases related to higher population density and population age structure. The clustering of autochthonous cases was generally mild, with prevailing isolated cases and a weak spread inside the munic

关键词： Aedes aegypti Vector-borne diseases Vector control Dengue epidemic

Removal of Basic Blue 9 Dye by Hydrogen Peroxide Activated by Electrogenerated Fe<sup>2+</sup>/Fe<sup>3+</sup>and Simultaneous Production of Hydrogen

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Journal of Environmental Protection 2015年第8期6卷 781-791页

作者： Yaneth Bustos-Terrones María Neftalí Rojas-Valencia Alberto álvarez-Gallegos Patricía García División de Estudios de Posgrado e Investigación-ingeniería ambiental Instituto Tecnológico de Culiacán Culiacán México Coordinación de ingeniería ambiental Instituto de Ingeniería Universidad Nacional Autónoma de México México D. F. México Centro de Investigación en ingeniería y Ciencias Aplicadas (CIICAp) Universidad Autónoma del Estado de Morelos Cuernavaca México

Electrochemical techniques were used to oxidize organic pollutants by Fenton process using a mix of H2O2 and ferrous ions at a parallel plate reactor. The first stage was to build a micro scale reactor comprising two compartments, cathode and anode, separated by a membrane (Nafion-117). Each compartment has inlets and outlets to allow the flow of fluids (10 Lmin-1). The function of the reactor is to oxidize organic pollutants as well as to produce H2. Hydrogen is electrogenerated in the catholyte by the reduction of protons on a carbon steel cathode in acidic medium (0.05 M H2SO4). At the same time, a mixture of Fe2+/Fe3+ ions is produced in the anolyte (0.05 M Na2SO4, pH ≈ 2) by means of the oxidation of a sacrificial electrode made of stainless steel mesh. Fe2+/Fe3+ ions interact with H2O2 to generate strong oxidants which are responsible for oxidizing the organic matter and removing color. A voltage of 1 V was applied between the electrodes and remained constant, while the current observed was approximately 0.06 A. Under these conditions, the activation rate with different H2O2 concentrations (15, 20, 25, 30, 35, 40, 45 and 50 mM) was evaluated. The maximum activation rate (1.3 mM·min-1) was obtained using 30 mM H2O2. Under these conditions, the oxidation of a synthetic industrial effluent (0.615 mM BB9) was performed and the following results were obtained: 95% of this concentration was removed in 5 minutes and 15 mL of H2 was electrogenerated in 30 minutes.

关键词： BB9 Degradation Fenton Process Hydrogen Peroxide Hydrogen Production