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Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems

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Journal of Mountain Science 2024年第3期21卷 719-733页

作者： G.Wilson FERNANDES Letícia RAMOS Dario C.PAIVA Jéssica CUNHA-BLUM Vanessa Matos GOMES Daniel NEGREIROS Ecologia Evolutiva&Biodiversidade Departamento de GenéticaEcologia e Evolução/ICBUniversidade Federal de Minas Gerais31270-901Belo HorizonteMGBrazil Knowledge Center for Biodiversity 31270-901Belo HorizonteMGBrazil Department of Biological Sciences Institute of EnvironmentFlorida International UniversityMiamiFL 33199USA Programa de Pós Graduação em Biodiversidade e Uso dos Recursos Naturais Universidade Estadual de Montes ClarosMontes ClarosMGBrazil Laboratório de Estudo das Relações Solo-planta Departamento de SolosUniversidade Federal Rural do Rio de JaneiroSeropédicaRGBrazil

Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the *** environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low *** determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological *** proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic *** described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and *** three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia *** distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt *** provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local *** to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem *** study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem.

关键词： Canga Ecological restoration Extreme ecosystem Non-forest ecosystems Rupestrian grassland Taxon environment relationships

Oxidative Degradation of Thermoplastic Starch Induced by UV Radiation

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Journal of Renewable Materials 2019年第4期7卷 383-391页

作者： Mayte M.Quispe Olivia V.López Marcelo A.Villar planta Piloto de Ingeniería Química PLAPIQUI(UNS CONICET)Bahía Blanca(8000)Argentina Departamento de Ingeniería Química Universidad Nacional del Sur(UNS)Bahía Blanca(8000)Argentina

Among biopolymers,thermoplastic starch(TPS)is a good candidate to obtain biomaterials because of its natural origin,biodegradable character,and *** to ultraviolet(UV)radiation causes significant degradation of starch-based materials,inducing photooxidative reactions which result in breaking of polymer chains,production of free radical,and reduction of molar *** changes produce a deterioration of TPS mechanical properties,leading to useless materials after an unpredictable *** this work,changes induced on TPS by UV radiation,analyzing structural properties and mechanical behavior,are *** was obtained through thermo-mechanical processing of native corn starch in the presence of water(45%w/w)and glycerol(30%w/w)as *** were obtained by thermocompression and,before testing,specimens were conditioned to reduce material *** process was performed by exposing TPS to 264 h UV radiation in a weathering test ***’s weight loss was determined *** changes were studied by Fourier Transform Infrared Spectroscopy(FTIR)and morphological modifications were analyzed by Scanning Electron Microscopy(SEM).Reduction of weight average molar mass was measured by Static Light Scattering(SLS).Changes in mechanical properties were studied from tensile *** 96 h exposure,TPS specimens presented a weight reduction of 4-6%,mainly attributed to plasticizers lost by *** observations showed that UV radiation induced morphological changes on TPS,evidenced by an increment of specimens *** FTIR,it was detected the presence of an additional band located at 1726 cm-1 in samples submitted to UV radiation,attributed to the formation of-C=O *** average molar mass of native starch was in the order of 107 g *** exposure to UV radiation decreased significantly its molar mass,confirming molecular degradation of the *** TPS was exposed during 48 h,it

关键词： Thermoplastic starch UV radiation structural properties mechanical behavior

Rheological Studies on Glycerol Plasticized Gelatin and Its Blends with Epoxidized Soybean Oil

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Journal of Renewable Materials 2019年第1期7卷 21-30页

作者： E.M.Ciannamea L.A.Castillo R.A.Ruseckaite S.E.Barbosa Instituto de Investigaciones en Ciencia y Tecnología de Materiales(INTEMA) Universidad Nacional de Mar del Plata-CONICETAv.J.B.Justo 4302Mar del PlataB7608FDQArgentina planta Piloto de Ingeniería Química(PLAPIQUI) UNS-CONICETCno.La Carrindanga Km.7Bahía Blanca8000Argentina Departamento de Ingeniería Química Universidad Nacional del SurAv.Alem 1253Bahía Blanca8000Argentina

Blends of gelatin(Ge)plasticized with varying amounts of glycerol(Gly),buffer solution pH 10 and epoxidized soybean oil(ESO)to enhance hydrophobicity were prepared by mixing and *** were characterized by rheological tests and microscopy to select optimal conditions for scaling up their *** effect of each component on rheological response was analyzed using parallel plate *** of gelatin specimens with PDMS during rheological tests led to reliable and reproducible results since water evaporation was prevented.A gradual increment in ESO concentration led to blends with increased degree of phase separation,as evidenced by optical and confocal *** compatibility between ESO and Ge increased viscosity at high ESO levels,but up to 10%Gly could be replaced with ESO without a significant variation of rheological behavior.

关键词： Rheology renewable plasticizers gelatin blends microstructure

Stable and efficient metal-biochar supported catalyst:degradation of model pollutants through sulfate radical-based advanced oxidation processes

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Biochar 2020年第3期2卷 319-328页

作者： Fermín Delgado Victoria S.Gutierrez Mariana Dennehy Mariana Alvarez INQUISUR Departamento de QuímicaUniversidad Nacional del SurAv.Alem 12538000 Bahía BlancaArgentina planta Piloto de Ingeniería Química PLAPIQUI(CONICET-UNS)Camino La Carrindanga Km 78000 Bahía BlancaArgentina

This study focuses on the synthesis of metal-based biochar catalysts and their catalytic activation of peroxymonosulfate(PMS,HSO5−)for the degradation of three different wastewater model pollutants employing advanced oxidation processes(AOP).Iron,copper,and two different cobalt-based catalysts were prepared and *** catalysts were supported on a biochar obtained from the pyrolysis of woody pruning *** were characterized by C,H,and N elemental analysis,X-Ray diffraction(XRD),Fourier-transform infrared spectroscopy(FTIR),and scanning electron microscope(SEM).The metal content in each catalyst was determined by means of atomic absorption spectroscopy(AAS).The degradation reac-tions of benzoic acid(BA),catechol(C),and cinnamic acid(CA)were carried out in a lab scale batch glass reactor and were followed by UV-Visible spectroscopy(UV-Vis).A colorimetric technique was employed to verify the presence of oxidant during the reaction *** catalyst/oxidant optimal ratio was determined for the cobalt *** mineralization degree of the pollutants after the degradations was verified by means of total organic carbon(TOC)content in the residual *** 4 h of reaction,the maximum mineralization was reached when C was treated with a cobalt-based catalyst(>80%),and its stability was evaluated through successive cycles of use.

关键词： Biochar Organic pollutants Advanced oxidation processes Sulfate radicals Cobalt catalysts

Climate Based Risk Assessment for Maize Producing Areas in Rainfed Agriculture in Mexico

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Journal of Water Resource and Protection 2014年第13期6卷 1228-1237页

作者： I.Sanchez Cohen G.Esquivel Arriaga M.A.Velasquez Valle Marco A.Inzunza Ibarra Arcadio Munoz Villalobos P.Bueno Hurtado Instituto nacional de Investigaciones Forestales Agrícolas y Pecuarias Centro Nacional de Investigacion Disciplinaria en Relacion Agua Suelo Planta Atmosfera(INIFAP-CENID RASPA)Km.6.5 Canal SacramentoZona Industrial Gomez PalacioDurangoMexico

Rainfed areas in Mexico accounts for 14 million hectares where around 23 million people live and are located in places where there is a little climatic information. The severe drought that has impacted northern Mexico in the past several years as well as other parts of the country, has forced decision takers to look for improved tools and procedures to prevent and to cope with this natural hazard. For this paper, the methodology of the Food and Agricultural Organization of the United Nations (FAO) for estimating water balance variables was modified to provide crop yield estimations under rainfed agriculture in maize producer states of Mexico. The water balance accounts for the daily variation of soil water content having main input rainfall (Pp) and main output crop evapotranspiration (Eta). The algorithm computes crop yield using two distinctive approaches: 1) one based on surplus/deficit functions for each crop considered and 2) yield estimations based on soil water balance and water function productions of the crop being analyzed. For computing water balance and crop yields, a computer model is built that incorporates the FAO method for water balance (MODEL SICTOD: Computational System for Decision Taking, acronym in Spanish) which stochastically generate precipitation based on wet/dry transition probabilities using a first order Markov chain scheme. Maps of average crop yields were obtained after interpolating model outcomes for the main maize producer states of Mexico: Jalisco, Michoacan, Guerrero, Puebla Oaxaca and Chiapas. Different planting dates were analyzed, early (90 days of length period), intermediate (120 days of length period) and late (150 days of length period). Crop yield variability correlates to the transition probability on having a wet day following a dry day. Results have shown high yield variation and probability of crop yield failure and climatic risk follows a distinctive pattern according to planting date and rainfall occurrence. The appr

关键词： Risk Assessment Water Balance Crop yield Simulation Rainfed

Biocomposites Based on Thermoplastic Starch and Granite Sand Quarry Waste

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Journal of Renewable Materials 2019年第4期7卷 393-402页

作者： María G.Passaretti Mario D.Ninago Cecilia I.Paulo Horacio A.Petit Edgardo F.Irassarc Daniel A.Vega Marcelo A.Villar Olivia V.López planta Piloto de Ingeniería Química PLAPIQUI(UNS-CONICET)Camino"La Carrindanga"Km 7Bahía Blanca8000Buenos AiresArgentina Departamento de Ingeniería Química Universidad Nacional del Sur(UNS)Bahía Blanca8000Buenos AiresArgentina Facultad de Ciencias Aplicadas a la Industria(FCAI) Universidad Nacional de Cuyo(UNCuyo)Bernardo de Irigoyen 375San Rafael5600MendozaArgentina Consejo nacional de Investigaciones Científicas y Técnicas(CONICET) Godoy Cruz 2290Ciudad Autónoma de Buenos AiresC1425FQBBuenos AiresArgentina Facultad de Ingeniería Universidad Nacional del Centro de la Provincia de Buenos Aires(UNCPBA).Centro de Investigaciones en Física e IngenieríaCIFICEN(UNCPBA-CICPBA-CONICET)7400OlavarríaArgentina Instituto de Física del Sur IFISUR(UNS-CONICET)Bahía Blanca8000Argentina

Granite stone is a by-product of the rock crushing *** industrial waste in powder form that causes health problems and environmental *** particles fraction can be used as a partial replacement of sand in concrete *** this work,an alternative exploitation of this waste fraction is *** sand(GS)with particles mean size of ~1μm was employed as thermoplastic starch(TPS)filler at different *** were obtained by melt-mixing and thermo-compression,achieving translucent and easy to handle films.A good GS dispersion within the matrix was evidenced by *** presence induced a shift of starch’s melting point to higher values and a better thermal *** UV absorption capacity was increased ~90% by GS *** increment in TPS young’s modulus and maximum tensile stress of 5 and 3 times,respectively was observed by adding 5%w/w GS.

关键词： Thermoplastic starch granite sand melt processing final properties

Multi-temporal NDVI analysis using UAV images of tree crowns in a northern Mexican pine-oak forest

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林业研究:英文版 2023年第6期34卷 1855-1867页

作者： JoséLuis Gallardo-Salazar Marcela Rosas-Chavoya Marín Pompa-García Pablito Marcelo López-Serrano Emily García-Montiel Arnulfo Meléndez-Soto Sergio Iván Jiménez-Jiménez Instituto de Investigaciones Agropecuarias y Forestales Universidad Michoacana de San Nicolás de Hidalgo(UMSNH)58330 MoreliaMichoacánMexico Programa Institucional de Doctorado en Ciencias Agropecuarias y Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Facultad de Ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Instituto de Silvicultura e Industria de la Madera Universidad Juárez del Estado de DurangoBoulevard del Guadiana 501Ciudad UniversitariaTorre de Investigación34120 DurangoMéxico INIFAP-CENID RASPA Centro nacional de Investigación Disciplinaria en Relación Agua-Suelo-planta-Atmósfera Margen derecha canal Sacramento km 6.5Zona industrial35140 Gómez PalacioDurangoMexico

The use of unmanned aerial vehicles(UAV)for forest monitoring has grown significantly in recent years,providing information with high spatial resolution and temporal *** with multispectral sensors allow the use of indexes such as the normalized difference vegetation index(NDVI),which determines the vigor,physiological stress and photo synthetic activity of *** study aimed to analyze the spectral responses and variations of NDVI in tree crowns,as well as their correlation with climatic factors over the course of one *** study area encompassed a 1.6-ha site in Durango,Mexico,where Pinus cembroides,Pinus engelmannii,and Quercus grisea *** images were acquired with UAV and information on meteorological variables was obtained from NASA/POWER *** ANOVA explored possible differences in NDVI among the three *** correlation was performed to identify the linear relationship between NDVI and meteorological *** differences in NDVI values were found at the genus level(Pinus and Quercus),possibly related to the physiological features of the species and their *** grisea had the lowest NDVI values throughout the year which may be attributed to its sensitivity to relative humidity and *** the use of UAV with a multispectral sensor for NDVI monitoring allowed genera differentiation,in more complex forest analyses hyperspectral and LiDAR sensors should be integrated,as well other vegetation indexes be considered.

关键词： Multispectral images Normalized diff erence Vegetation index Phenology Unmanned aerial vehicles Multitemporal analysis

Flavonols Protect Arabidopsis Plants against UV-B Deleterious Effects

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Molecular Plant 2013年第4期6卷 1376-1379页

作者： Julia Emiliani Erich Grotewold María Lorena Falcone Ferreyra Paula Casat Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI) Universidad Nacional de Rosario Suipacha 531 2000 Rosario Argentina Center for Applied Plant Sciences The Ohio State University Columbus OH 43210 USA Department of Molecular Genetics The Ohio State University Columbus OH 43210 USA

Dear Editor, Flavonols are synthesized by flavonol synthase （FLS） enzymes （Martens et al., 2010）. These compounds absorb UV-B light in the 280-320-nm region and their concentration increases in plants exposed to environmental abiotic and biotic stresses, including UV-B; consequently, flavonols are thought to act as UV-B filters （Agati et al., 2011）. It has been also suggested that these metabolites function as reactive oxygen species （ROS） scavengers, as they contain an OH- group in the 3-position of the flavonoid skeleton, which allows them to chelate metals, inhibiting the formation of free radicals and ROS accumula- tion, once formed （Agati et al., 2009）. For these reasons, it has been suggested that flavonols play uncharacterized roles in UV responses （Verdan et al., 2011）. Nevertheless, despite the fact that the role of flavonols in UV-B protection has been inferred, the protection conferred by flavonols on the target sites of UV-B-damage has not been directly proven in planta.

关键词： Arabidopsis UV-B Deleterious

Performance of Brooders,Fry and Growth of the Nile Tilapia(Oreochromis niloticus)Cultured in an Experimental Recirculating Aquaculture System

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Agricultural Sciences 2015年第9期6卷 1014-1022页

作者： Jose Luis Arredondo-Figueroa Laura Georgina Nunez-García Jesus T.Ponce-Palafox Irene de Los Angeles Barriga-Sosa Unidad Acuícola Departamento de ZootecniaUniversidad Autonoma de AguascalientesAguascalientesMéxico planta Experimental de Produccion Acuicola Division de Ciencias Biológicas y de la SaludDepartamento de HidrobiologíaUniversidad Autónoma Metropolitana IztapalapaMéxicoD.F.México Centro de Innovación y Transferencia Tecnológica CENITT Posgrado CBAPEscuela Nacional de Ingeniería PesqueraUniversidad Autónoma de NayaritTepicMéxico

We present results of a long-term study aimed to optimize Nile tilapia O. niloticus production in a recirculating aquaculture system (RAS) in México City. Three experiments were evaluated: 1) fry production;2) production of masculinized fries;and 3) assessment of growth under three different densities (10, 30 and 75 fish/m3). The broodstock produced on average 2400 ± 600 fry every 15 days during six months, with a total production of 28,800 ± 2000. One hundred percent males were produced in 274-L raceways in an eight-week period. The obtained results in fish production in the RAS system indicated variations related to density. A daily growth rate of 3.6 g/day was registered with a density of 10 fish/m3, 0.9 g/day in 30 fish/m3 and 0.4 g/day in 75 fish/m3. This information could be useful for production purposes in this type of systems.

关键词： Tilapia Oreochromis niloticus Intensive Culture Sex Reversal Growth Densities