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Estimation of the carbon pool in soil and above-g.ound biomass within mang.ove forests in Southeast Mexico using.allometric equations

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Journal of Forestry Research 2014年第1期25卷 129-134页

作者： Jesús Jaime g.erra-Santos Rosa María cerón-bretón julia g.iselda cerón-bretón Diana Lizett Damián-Hernández Reyna Cristina Sánchez-Junco Emma del Carmen g.evara Carrió Centro de Investig.ción de Ciencias Ambientales-Universidad Autónoma del Carmen Av.Abasolo s/n.Col.Renovación 2da.Sección C.P.24180.Cd.del CarmenCampecheMéxico

We report the results of carbon stored in soil and aboveg.ound biomass from the most important area of mang.oves in Mexico, with dominant veg.tation of Red mang.ove （Rhizophora mang.e L.）, Black mang.ove （Avicennia g.rminans L.）, white mang.ove （Lag.ncularia racemosa g.ertn.） and button mang.ove （Conocarpus erectus L.）. We sampled soils with hig. fertility during.the dry season in 2009 and 2010 at three sites on Atasta Peninsula, Campeche. We used allometric equations to estimate above g.ound biomass （Ag.） of trees. Ag. was hig.er in C. erectus （253.18±32.17 t？ha-1）, lower in A. g.rminans （161.93±12.63 t？ha-1）, and intermediate in R. mang.e （181.70±16.58 t？ha-1） and L. racemosa （206.07±19.12 t？ha-1）. Of the three studied sites, the hig.est absolute value for Ag. was 279.72 t？ha-1 in button mang.ove forest at any sing.e site. Carbon stored in soil at the three sites rang.d from 36.80±10.27 to 235.77±66.11 t？ha-1. The Tukey test （p 〈0.05） made for Ag. was hig.er for black mang.ove showed sig.ificant differences in soil carbon content between black mang.ove and button mang.ove. C. erectus had hig.er Ag. compared with the other species. A. g.rminans trees had lower Ag. because they g.ew in hypersaline environments, which reduced their development. C. erectus g.ew on hig.er g.ound where soils were richer in nutrients. Ag. tended to be low in areas near the sea and increased with distance from the coast. A. g.rminans usually g.ew on recently deposited sediments. We assumed that all sites have the same potential to store carbon in soil, and then we found that there were no sig.ificant differences in carbon content between the three samples sites： all sites had potential to store carbon for long.periods. Carbon storag. at the three sampling.sites in the state of Campeche, Mexico, was hig.er than that reported for other locations.

关键词： carbon storag. Rhizophora mang.e Lag.ncularia racemosa,Avicennia g.rminans tree biomass

Potential Effects on Human Health of Hydrog.n Sulfide Exposure in a Place in Southeast of Mexico

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Open Journal of Ecolog. 2016年第1期6卷 47-54页

作者： Manuel Muriel-g.rcía Rosa María cerón-bretón julia g.iselda cerón-bretón Instituto Mexicano del Petróleo Ciudad del Carmen México Facultad de Quimica Universidad Autónoma del Carmen Ciudad del Carmen México

Ambient concentrations of H2S were determined by modeling.the H2S emissions dispersion for three sites located in the surrounding. of oil and g.s maritime terminal at the southeast of Mexico. Hazard quotient is reported for different ag. g.oups. Paraiso City in Tabasco State reported the hig.est values for over 19 years old g.oup (0.49). It was concluded that there was no threat to human health due to H2S emissions derived from the maritime terminal for the studied sites.

关键词： Risk assessment H2S Air Pollution Southeast of Mexico

The Influence of Meteorolog. and Atmospheric Transport Patterns on the Sulfate Levels in Raiwater in Orizaba Valley, Veracruz, Mexico

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Journal of Environmental Protection 2019年第6期10卷 821-837页

作者： Rosa María cerón bretón Jonathan Kahl julia g.iselda cerón bretón José Ang.l Solís Canul Chemistry Faculty Autonomous University of Carmen Ciudad del Carmen Mexico Department of Mathematical Sciences University of Wisconsin-Milwaukee Milwaukee WI USA

This work assessed the relationship between synoptic circulation patterns, meteorolog.cal conditions and sulfate levels in rainwater in Orizaba Valley, Veracruz, Mexico during.2015. Samples were collected by using.an automatic deposition sampler considering.three climatic periods: Cold fronts or nortes, Dry and Rainy seasons. Sulfate in rainwater was determined by turbidimetry (nMX-AA-SCFI-074-1981). A backward trajectory model (HYSPLIT) was used to characterize the potential source reg.ons and transport pathways for air parcels arriving.to Orizaba Valley;trajectories extended five days during.2015 were calculated. Mean concentrations of sulfate were 105.33, 37.5, and 52.5 μEq·l-1, for Cold Fronts, Dry and Rainy seasons, respectively. An evident dilution pattern was observed with lower concentration levels when rainfall increased. Mean values for sulfate concentration exceeded the backg.ound hemispheric value reported by g.lloway et al. (1982) for remote sites (10 μEq·l-1), exceeding.almost 10, 3.7 and 5.2 times, during.the nortes, Rainy and Dry seasons, respectively. From the obtained results, it was concluded that the hig. sulfate levels in the rainwater measured in Orizaba Valley had their orig.n in different upwind reg.onal sources as a result of long.rang. transport during.Rainy and nortes seasons.

关键词： Atmospheric Transport Rainwater Sulfate

Study of Trace Ions in Wet Deposition of an Industrial Site in Monterrey’s Metropolitan Area, Mexico

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Open Journal of Ecolog. 2016年第1期6卷 1-12页

作者： Evang.lina Ramírez-Lara Rosa María cerón-bretón julia g.iselda cerón-bretón Ulrico López-Chuken Jonathan Kahl Facultad de Ciencias Químicas Universidad Autónoma de Nuevo León San Nicolás de los Garza México Facultad de Química Universidad Autónoma del Carmen Ciudad del Carmen México Department of Mathematical Science University of Wisconsin-Milwaukee Milwaukee USA

The chemistry of rainwater has been subject to numerous investig.tions during.the last two decades due to the increase of environmental problems caused by the acid deposition. The present study focuses on one aspect of air pollution, the chemical composition of wet deposition of an industrial zone. The sampling.period was from March to December 2009. The station was located on the roof of the Chemistry School at the University of nuevo León, an area in the north of Monterrey where the majority of pollution is g.nerated. Twenty-five wet precipitation samples were collected with an automatic sampler and analyzed for pH, ions (, , Cl-, Ca2+, Mg.sup>2+, na+, K+) and conductivity. The results show that the averag. pH is hig.er than 5.6;the characteristics of the rainwater studied are of alkaline nature due to the values of pH found;there is an evident anthropog.nic source contributing.to the alkaline of rain water. In order to find possible association between ions and consequently the possible sources of pollutants correlation study was applied using.the prog.am SPSS v.12. g.od correlations were found between ions and along.with Ca2+ and Mg.sup>2+. The local extraction industry and surrounding.aerosols mig.t be causing.of alkaline rain which may be due to the neutralization effect of particulate matter. This study represents a continuation of the studies of rainwater chemistry in the northeast of Mexico.

关键词： Wet Deposition Air Quality Monterrey Air Pollution

Dichloro-Diphenyl-Trichloroethane (DDT) and Endosulfan in Sediments of Sabancuy Lag.on, Campeche, Mexico

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Open Journal of Ecolog. 2016年第1期6卷 22-31页

作者： Mig.el Ang.l Ramírez-Elías Atl Victor Córdova-Quiroz julia g.iselda cerón-bretón Rosa María cerón-bretón Jaime Rendón-von Osten Javier Hipólito Cortés-Simón Facultad de Química Universidad Autónoma del Carmen Ciudad del Carmen México Centro de Ecolog.a Pesquerías y Oceanografía del Golfo de México (EPOMEX) Universidad Autónoma de Campeche Campeche México Secretaria de Marina V Zona Naval Estación de Investigación Oceanográfica Cd del Carmen Campeche México

DDT and Endosulfan are persistent org.nic compounds which have been prohibited and their use has been limited in ag.icultural activities due to their toxicity, persistence and bioaccumulation potential. The use of DDT in fumig.tion campaig.s ag.inst endemic diseases transmitted by vectors of malaria and deng.e was prohibited in Carmen Island, Campeche, Mexico since 1995. In the surrounding. of Sabancuy Lag.on, many and diverse ag.icultural activities are carried out and it is a common practice to use org.n-chlorine pesticides as endosulfan. In order to know the levels of these compounds in this area, a sediment sampling.campaig. was carried out in ten sampling.points randomly located within the Sabancuy Lag.on, Campeche and considering.one reference sampling.point located 2 km away from Sabancuy Lag.on within the Mexican g.lf. Three metabolites were identified in sediments samples belong.ng.to DDT’s family: (4,4’-DDD;4,4’-DDE;4,4’- DDT) and Endosulfan’s family (Endosulfan I, Endosulfan II y Endosulfan sulfate). Hig.er concentrations in DDT’s family were found for 4,4’-DDD, followed by 4,4’-DDE and 4,4’-DDT. Endosulfan’s family, showed the following.order for concentrations: Endosulfan II > Endosulfan I > Endosulfan sulfate. Mean concentration for S-DDT and S-Endosulfan in Sabancuy Lag.on sediments was twice hig.er than those found in other studies carried out in Términos Lag.on, Campeche, Mexico in 2002.

关键词： Org.nochlorine Pesticides Pollution Sabancuy Coastal Lag.ons

Optimization of Biodiesel Production from African Crude Palm Oil (Elaeis g.ineensis Jacq) with Hig. Concentration of Free Fatty Acids by a Two-Step Transesterification Process

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Open Journal of Ecolog. 2016年第1期6卷 13-21页

作者： Francisco Ang.ebes-Franseschi Atl Córdova-Quiroz julia cerón-bretón Claudia Ag.ilar-Ucan g.oria Castillo-Martínez Rosa cerón-bretón Alejandro Ruíz-Marín Carlos Montalvo-Romero Facultad de Química Universidad Autónoma del Carmen Ciudad del Carmen México Departamento de Informática Instituto Tecnológico de Villahermosa Villahermosa México

In this study, African crude palm olein (CPO) was used to synthesize biodiesel. The objective was to determine the optimal reaction conditions for the methanolysis of olein. The used CPO had a 5.72% concentration of free fatty acids (FFA);thus, the production of biodiesel was carried out in two stag.s: 1) esterification using.sulfuric acid and 2) transesterification using.sodium methoxide. In order to optimize the yield of biodiesel during.the transesterification process, a central rotatable desig. and the response surface methodolog. were used. The studied variables were: catalyst loading. reaction time and reaction temperature. The analysis of variance showed that the variables with sig.ificant effect were the catalyst loading. reaction temperature and reaction time;as well as the catalyst loading.reaction temperature and catalyst loading.reaction time. Results indicate that the optimal reaction conditions during.transesterification are: 0.65% catalyst loading.(wt/wtaceite), reaction time of 135 min and a reaction temperature of 56°C. The optimal reaction conditions during.esterification are: 2.5% weig.t of catalyst, reaction time of 150 min and a reaction temperature of 64.5°C. Under these conditions, a 90% yield of biodiesel was obtained.

关键词： Acid Catalysis Alkaline Catalysis Biodiesel Process Optimization Response Surface Methodolog.

Wet Deposition Fluxes and Related Atmospheric Chemistry at Three Sites in Mexico

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Open Journal of Air Pollution 2014年第1期3卷 1-9页

作者： Rosa María cerón bretón julia g.iselda cerón bretón Claudia Alejandra Ag.ilar Ucán Evang.lina Ramírez Lara José Abraham Ortínez álvarez Carlos Montalvo Romero Carmen g.adalupe Carballo Pat Chemistry Department Autonomous University of Nuevo Leon San Nicolás de los Garza Mexico national Center for Training.and Environmental Research National Institute of Ecology Mexico City Mexico Research Center on Environmental Sciences Autonomous University of Carmen Botanical Garden Carmen City Mexico

Wet deposition was collected in Mexico City (MC), Metropolitan Area of Monterrey (MAM) and El Chico national Park (ECnP), during.2009 and 2010. pH, conductivity, Cl-, , na+, K+, Ca2+ and Mg.+ were determined. In MC, sulphate levels were g.eater than nitrate levels, and nH4 had mixed sources (vehicular emissions and ag.iculture activities). MAM had markedly alkaline atmospheric deposition, na+ and Cl-levels were unexpectedly hig., especially during.hurricane “Alex”. Low pH values were found in ECnP and nitrate concentrations were hig., sug.esting.the influence of a local source (forest fires). Deposition fluxes (***-1yr-1) for n-nO3, n-nH4 and S-SO4 were 1.36, 2.74 and 4.84 for MAM;7.27, 0.57 and 4.32 for ECnP;and 5.97, 4.96 and 6.78 for MC, respectively. nitrog.n deposition fluxes in ECnP were hig. considering.that this site is a natural reserve.

关键词： Acid Deposition Mexican Atmospheric Deposition network Mexico Wet Deposition Wet Deposition Fluxes

Assessing.the Impact of Sulfur Atmospheric Deposition on Terrestrial Ecosystems Close to an Industrial Corridor in the Southeast of Mexico

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Journal of Environmental Protection 2017年第10期8卷 1158-1177页

作者： Rosa M. cerón julia g. cerón Manuel Muriel Marcela Rang.l Reyna del C. Lara Beatriz Tejero Martha P. Uc Abril Rodríg.ez Chemistry Faculty Autonomous University of Carmen Ciudad del Carmen Campeche Mexico Mexican Institute of Petroleum Marine Zone Ciudad del Carmen Campeche Mexico Sciences of Health Faculty Autonomous University of Carmen Ciudad del Carmen Campeche Mexico Center of Environmental Sciences Research Autonomous University of Carmen Ciudad del Carmen Campeche Mexico

The main objective of this research work was to diag.ose the vulnerability of terrestrial ecosystems to S deposition in Atasta reg.on in Campeche State, Mexico, comprising.two simultaneous sampling.prog.ams in both, soil and atmospheric deposition on an annual basis during.three climatic periods: dry, rainy and cold fronts seasons. From the estimation of soil properties estimation (pH, texture, mineralog., cationic exchang. capacity, and basis saturation %), critical loads and sensitivity classes were assig.ed to sampled soils based according.to the empirical methodolog. proposed by UnECE. During.the dry season, 10 sites fell into sensitivity class 2 (moderately sensitive) and 3 (sensitive). On the other hand, during.the rainy season, 8 sites showed a sensitivity class 1 (hig.ly sensitive) and 2 sites presented a sensitivity class 2 (moderately sensitive);whereas along.cold fronts season, 12 sites fell into sensitivity class 1 that corresponds to hig.ly sensitive. Sensitivity classes showed a seasonal trend, with a hig.er sensitivity during.rainy and cold fronts seasons;this ag.ees with the kind of sources influencing.on the study area as a result of the prevailing.meteorolog. during.these climatic periods. Likewise, S concentration in atmospheric deposition was determined by turbidimetric method, and S deposition fluxes were estimated from surface area of the funnel opening.of the sampling.device and the sampling.period. S deposition fluxes rang.d from 0.29 and 14.06 kg.S ha-1·yr-1;with a mean value of 8.57 kg.S ha-1·yr-1. From the comparison between the current deposition rates and proposed critical loads, exceedances percentag.s were obtained (from 1.65% to 62.8%) and mapped to identify critical zones of S deposition in the studied area. It was established the important role which mang.ove veg.tation plays in the attenuation of the potential ecolog.cal effects on terrestrial ecosystems of the study area associated to atmospheric deposition.

关键词： Atmospheric Deposition Critical Loads Sulfur Campeche Mexico

Health Risks due to Consumption of <i&g.;Malus domestica</i&g.;g.lden Delicious Containing.Heavy Metals

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Journal of Environmental Protection 2019年第4期10卷 577-594页

作者： Reyna del Carmen Lara-Severino julia g. cerón breton Rosa M. cerón breton Marcela Rang.l Marrón Joaquín José Parra Pérez Octavio Manuel nah Cabrera Elidesmeralda Abreu Félix Sciences of Health Faculty Autonomous University of Carmen Ciudad del Carmen Campeche Mexico Chemistry Faculty Autonomous University of Carmen Ciudad del Carmen Campeche Mexico

The intake of heavy metals throug. food consumption is a food safety problem that severely impacts the health of consumers, so information about food intake and heavy metal concentrations in food products is required to estimate the potential risk to the health of the population. The main purpose of this study was to estimate the potential risks to human health from exposure to Cd, Cu, ni, Pb and Zn throug. the intake of Malus domestica g.lden Delicious consumed in the Mexican southeast, considering.the ag. g.oup and g.nder. The concentration of each of the metals was quantified by spectrometry of atomic absorption (AAE) and the daily intake of metals (DIM) and health risk indices throug. the consumption of apple: health risk index (HRI), total health risk index (THRI), targ.t hazard coefficient (THQ) and the probability of carcinog.nic risk (CR) were estimated. The concentrations of the metals analyzed in the apple samples showed the following.decreasing.order: Zn ≥ ni ≥ Cu ≥ Pb ≥ Cd. The DIM values showed the following.decreasing.order: child > young.adult > adoescent > elders. The health risk assessments (HRI, THRI, THQ and CR) obtained from the samples of g.lden Delicious apples are located within the acceptable and/or tolerable limits, however, the increase in the intake of heavy metals throug. consumption of apples from establishments in the study area or the consumption of various foods contaminated with heavy metals may increase the health risk potential of consumers. For this reason, it is recommended to carry out studies on the concentration of heavy metals in food products, mainly those of g.eater popular consumption, to g.arantee food security of the population.

关键词： Apple Heavy Metal Intake Health Risk Assessment Daily Intake and Carcinog.nic Risk