Gomez-Aiza L.,Instituto Nacional Of Ecologia Y Cambio Climatico |
Gomez-Aiza L.,National Autonomous University of Mexico
Land Use Policy | Year: 2017
Climate change and land use/land cover change (LULCC) are associated with local vulnerability, defined as the intrinsic tendency of a system to be negatively affected by an event or phenomenon, but this can be ameliorated by ecosystem conservation. In Mexico, extensive Wildlife Management Units (eWMUs) are environmental policy instruments designed to promote ecosystem conservation and rural development via the sustainable use of wildlife by local populations. However, evidence of the successful reduction of LULCC by eWMUs is contradictory, and there has been no investigation into their potential as an action to promote climate change adaptation. In this study, we focused on the overall patterns of LULCC associated with eWMU throughout the country and examined strengths and weaknesses of eWMUs as policy instruments to address climate change. In particular, we analyzed how differences in areas with eWMUs influence LULCC and assessed how eWMUs could contribute to reducing vulnerability, particularly in double exposure municipalities. We calculated the percentage of eWMUs per municipality from official information and estimated LULCC from vegetation changes between 2002 and 2011. We then used the Kruskal-Wallis test to find statistically significant differences in vegetation changes based on the percentage of eWMUs and performed between-group comparisons using a post hoc Dunn test. Although Mexico has 2456 municipalities, only 37% have eWMUs. Furthermore, 64% of Mexico's municipalities have lost vegetation cover, whereas only 36% have either gained vegetation or remained stable. In municipalities that recorded changes to the vegetation, those changes were, overall, minimal and involved less than 10% of the total area of those municipalities. In general, municipalities with less than 10% of their total area dedicated to eWMUs experienced higher vegetation losses than those with more than 10% of their total area dedicated to eWMUs. We detected twelve double exposure municipalities, i.e. they are vulnerable to climate change and lost more than 10% of their vegetation. Double exposure municipalities dedicated less than 2% of their total area to eWMUs as well. Our results suggest that incremental increases in the area dedicated to eWMUs may reduce LULCC and protect vegetation, particularly in double exposure municipalities. Based on the literature, some ecological, economic and socio-cultural factors may determine the success of eWMUs and strongly impact LULCC. Therefore, additional efforts must be made to enhance our understanding of ecological and climatic processes; habitats must be monitored using a standardized methodology; biological, cultural, economic and institutional diversity must be incorporated into the planning, implementation and monitoring of eWMUs; and agreements must be established to strengthen social organization and human capital. Taking all this into account, we suggest that reducing vulnerability and improving double exposure areas by increasing the number and interconnectedness of eWMUs could represent an effective strategic approach at the municipal level to address LULCC and climate change. © 2017 Elsevier Ltd
Baker C.S.,Oregon State University |
Steel D.,Oregon State University |
Calambokidis J.,Cascadia Research Collective |
Falcone E.,Cascadia Research Collective |
And 15 more authors.
Marine Ecology Progress Series | Year: 2013
ABSTRACT: We quantified the relative influence of maternal fidelity to feeding grounds and natal fidelity to breeding grounds on the population structure of humpback whales Megaptera novae - angliae based on an ocean-wide survey of mitochondrial (mt) DNA diversity in the North Pacific. For 2193 biopsy samples collected from whales in 10 feeding regions and 8 breeding regions during the winter and summer of 2004 to 2006, we first used microsatellite genotyping (average, 9.5 loci) to identify replicate samples. From sequences of the mtDNA control region (500 bp) we identified 28 unique haplotypes from 30 variable sites. Haplotype frequencies differed markedly among feeding regions (overall FST = 0.121, FST = 0.178, p > 0.0001), supporting previous evidence of strong maternal fidelity. Haplotype frequencies also differed markedly among breeding regions (overall FST = 0.093, FST = 0.106, p > 0.0001), providing evidence of strong natal fidelity. Although sex-biased dispersal was not evident, differentiation of microsatellite allele frequencies was weak compared to differentiation of mtDNA haplotypes, suggesting male-biased gene flow. Feeding and breeding regions showed significant differences in haplotype frequencies, even for regions known to be strongly connected by patterns of individual migration. Thus, the influence of migratory fidelity seems to operate somewhat independently on feeding and breeding grounds over an evolutionary time scale. This results in a complex population structure and the potential to define multiple units to conserve in either seasonal habitat.© Inter-Research 2013. www.int-res.com.
Rodrigues E.R.,National Autonomous University of Mexico |
Gamerman D.,Federal University of Rio de Janeiro |
Tarumoto M.H.,São Paulo State University |
Tzintzun G.,Instituto Nacional Of Ecologia Y Cambio Climatico
Environmental and Ecological Statistics | Year: 2015
In this work we consider a non-homogenous Poisson model to study the behaviour of the number of times that a pollutant’s concentration surpasses a given threshold of interest. Spatial dependence is imposed on the parameters of the Poisson intensity function in order to account for the possible correlation between measurements in different sites. An anisotropic model is used due to the nature of the region of interest. Estimation of the parameters of the model is performed using the Bayesian point of view via Markov chain Monte Carlo (MCMC) algorithms. We also consider prediction of the days in which exceedances of the threshold might occur at sites where measurements cannot be taken. This is obtained by spatial interpolation using the information provided by the sites where measurements are available. The prediction procedure allows for estimation of the behaviour of the mean function of the non-homogeneous Poisson process associated with those sites. The models considered here are applied to ozone data obtained from the monitoring network of Mexico City. © 2014, Springer Science+Business Media New York.
Gavilan-Garcia I.C.,National Autonomous University of Mexico |
Fernandez-Villagomez G.,National Autonomous University of Mexico |
Gavilan-Garcia A.,Instituto Nacional Of Ecologia Y Cambio Climatico |
Alcantara-Concepcion V.,Instituto Nacional Of Ecologia Y Cambio Climatico
Journal of Cleaner Production | Year: 2014
Mercury releases from used thermometers at the end of their life in the Mexican health sector are estimated to be 2166 kg/year. Some actions are being implemented at the hospital level to eliminate the use of mercury thermometers in some cities. This study evaluated the impact of policy alternatives for the sound management of mercury released from used thermometers using a life cycle assessment with Umberto software and Ecoinvent databases. The results identified that the elimination of open dumping and increasing the recycling rate of mercury up to 60% will lead to the highest net benefits compared with the use of virgin materials in new products. This study showed different scenarios of recycling and end of life practices in the management of mercury waste from glass thermometers in Mexico to know the environmental burdens of each treatment strategy and identified recommendations for development of public policies for handling of this type of waste with focus in the decrease of associated risks. It was demonstrated that increase of recycling allows reducing the environmental impacts caused by the use of raw materials and that decrease of landfills for deposit of mercury waste, preventing uncontrolled emissions of mercury to the atmosphere. © 2014 Elsevier Ltd. All rights reserved.
Alcantara-Concepcion V.,Instituto Nacional Of Ecologia Y Cambio Climatico |
Gavilan-Garcia A.,Instituto Nacional Of Ecologia Y Cambio Climatico |
Gavilan-Garcia I.C.,National Autonomous University of Mexico
Journal of Cleaner Production | Year: 2016
A Life Cycle Analysis of End-of-Life Computers was developed for management of computers discarded in Mexico for the year 2014 through LCA methodology (ISO 14044) and using specialized software named Umberto® version 5.5.4 with database Ecoinvent 2.2. The modeling consisted in the current scenario in Mexico (10% recycling) versus four alternative scenarios: 0% recycling, 25% recycling, 35% recycling and elimination of open dump disposal considering experience in other countries and real possibilities of medium-term management. All practices of management and recycling are considered in the model with changes in the recycling rates and installed infrastructure for different alternatives proposals. On the other hand, the model included that dismantling operations are done mostly with manual labor; transportation, extraction and processing of printed wiring boards, including local process of transforming, heating and melting of materials and considering recycling in Asian countries with all the environmental burdens processes involving transoceanic transportation and metallurgy. The majority of non-precious metals recycling was considered to take place locally. A substantial benefit was identified for all recycling scenarios, particularly in the elimination of open dump disposal and the recycling of 35% of the stream and was found that there was a high impact on climate change and adverse toxic effects to health and natural environments for the practice of accumulating waste in sanitary landfills and dumpsites as well as by burning of materials (plastics and others) in open areas. The use of recycled materials versus virgin materials was also beneficial up to 10 times for reduction in global warming potential impact and up to 3 times reduction for human toxic potential. Public policies might be recommended in order to protect health and environment. As public policy recommendations, it is proposed reinforcement the national infrastructure to collect EoL computers- and transformation of materials into new commercial products, and as a starting point for the recycling of all generated materials, including plastics and printed wiring boards, but should also include the promotion of research for the transformation of plastic waste and the implementation of new technologies that can be adopted by the national recycling industry and create new regulations that result in the production or import of EoL computers and other electronics with low levels of toxic substances as their main components. Other public policies should include the legal prohibition of use of landfills and dumps for containment of EoL computers and other electrical and electronic equipment. © 2016 Elsevier Ltd.
Linking geomorphologic knowledge, RS and GIS techniques for analyzing land cover and land use change: A multitemporal study in the Cointzio watershed, Mexico [Conectando conhecimento geomorfológico, percepção remota e técnicas de geoprocessamento para a análise de cobertura da terra e mudanças no uso da terra: Um estudo multitemporal na bacia Cointzio, México]
Lopez-Granados E.,Universidad Michoacana de San Nicolás de Hidalgo |
Mendoza M.E.,National Autonomous University of Mexico |
Gonzalez D.I.,National Autonomous University of Mexico |
Gonzalez D.I.,Instituto Nacional Of Ecologia Y Cambio Climatico
Revista Ambiente e Agua | Year: 2013
It is well-established that changes in land cover and land use (LCLU) are relevant to current local and global changes that are directly linked with food security, human health, urbanization, biodiversity, trans-border migration, environmental refuges, water and soil quality, runoff and sedimentation rates, and other processes. This paper examines LCLU change processes within the Cointzio watershed (Central Mexico). The analysis covers a 28-year time period from 1975 to 2003. LCLU changes were deduced from multi-temporal remote sensing analyses (1975, 1986, 1996, 2000 and 2003). Nearly all of the LCLU changes experienced in the Cointzio watershed occurred during the 1986-1996 period. Half of the 665 km2 of the watershed have changed during this period, in what corresponds to a ten-fold increase in the rate of change as compared to the 1975-1986 and 1996-2003 periods. These massive changes are probably related to the Immigration Reform and Control Act (IRCA) of 1986, which limited the transit of undocumented Mexican workers to the United States of America. The methodology applied in this research constitutes a low-cost alternative for evaluating the impact of LCLU change in watersheds. The magnitude of land use change differed during the periods of analyses in the watershed, functional zones and geoforms. The methodological approach applied in this analysis integrates standard procedures to evaluate land cover and land use change in watersheds. Due to the practical value of the results, the data and information generated during the analysis have been made available to local authorities.
Espinosa M.D.L.L.,National Autonomous University of Mexico |
Martinez A.,National Autonomous University of Mexico |
Martinez A.,Instituto Nacional Of Ecologia Y Cambio Climatico |
Peralta O.,National Autonomous University of Mexico |
Castro T.,National Autonomous University of Mexico
Environmental Chemistry | Year: 2016
Environmental context Dimethylsulfide (DMS), the main biogenic sulfur compound in the atmosphere, is produced by the marine biosphere and plays an important role in the atmospheric sulfur cycle. This study recorded the spatial variability of DMS and dissolved and particulate dimethylsulfoniopropionate (DMSP) in the water column of the southern Gulf of Mexico. The results suggest that the spatial variability of DMS and DMSP is directly related to the hydrodynamics of the study area. Abstract The spatial variability of dimethylsulfide (DMS) and dissolved and particulate dimethylsulfoniopropionate (DMSPd and DMSPp) was recorded in the southern Gulf of Mexico at three different depths (10, 30 and 60m) in January 2013. DMS and DMSP values were recorded through solid-phase microextraction coupled to gas chromatography. Average concentrations of DMS (2.8±1.5nM), DMSPd (1.7±0.9nM) and DMSPp (352±157nM) were significantly correlated with chlorophyll-a concentrations and the depth of the mixed layer. Vertical concentration profiles were similar, indicating a well-mixed water column with a thermocline at a depth of 50-100m. Average DMS sea-to-air flux was 5.0±1.7μmolm-2day-1. The greatest fluxes were recorded at the stations in the western region of the study area, owing to the combined effect of high DMS concentrations (3.7-7.21nM) and a high wind speed (4.4-6.8ms-1). The greatest concentrations were recorded at the stations nearest the coast. The distribution of DMS and DMSP was apparently related to the oceanic hydrodynamics. © CSIRO 2016.
Gavilan-Garcia I.,National Autonomous University of Mexico |
Tovar-Galvez L.R.,National Polytechnic Institute of Mexico |
Beristain-Montiel E.,National Autonomous University of Mexico |
Gavilan-Garcia A.,Instituto Nacional Of Ecologia Y Cambio Climatico |
Amador-Munoz O.,National Autonomous University of Mexico
Environmental Earth Sciences | Year: 2016
Solid waste disposal sites receive an increasing quantity of products with polybrominated diphenyl ethers (PBDE) from inadequate management of end of life products containing them. These chemicals are released in the landfill leachate and can represent a risk to health and the environment. In this study, concentration of eight PBDE congeners was analyzed in polymer samples from e-waste from two landfills in Mexico City (East and North). Total PBDE content ranged from non-detectable to 90.8 ± 1.9 µg/g in a total of 40 samples. An association with the use of the commercial mixtures was done. From these, and using official data of flows and composition of the wastes, a total flow of PBDEs into the landfills was estimated as 110.56 g PBDEs/day into the North side landfill (28 ha and 850 tons day−1 of solid waste) and 15,470 g PBDEs/day into the East side landfill (375 ha and 13,300 tons day−1 of solid waste until closure). These chemicals can contaminate underground water. © 2016, Springer-Verlag Berlin Heidelberg.
Velasco A.,Instituto Nacional Of Ecologia Y Cambio Climatico |
Velasco A.,Metropolitan Autonomous University |
Hernandez S.,Metropolitan Autonomous University |
Ramirez M.,Instituto Nacional Of Ecologia Y Cambio Climatico |
Ortiz I.,Metropolitan Autonomous University
Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes | Year: 2014
Organochlorine pesticides were intensively used in Mexico from 1950 until their ban and restriction in 1991. However, the presence of these compounds is commonly reported in many regions of the country. The aim of the present study was to identify and quantify residual organochlorine and organophosphorus pesticides in agricultural soil in Rio Verde region, San Luis Potosi state, which has been identified as possibly polluted by pesticides. Composed samples from 24 zones covering an area of approximately 5,440 ha were analyzed. The most frequently found pesticides were p,ṕ-DDT followed by,p,ṕ-DDE, heptachlor, endosulfan and γ-HCH whose frequency rates were 100, 91, 83 and 54%, respectively. The concentration of p,ṕ-DDT in the crops grown in these soils was in the following order: chili > maize > tomato > alfalfa. The results obtained in this study show that p,ṕ-DDT values are lower or similar to those found in other agricultural regions of Mexico. Methyl and ethyl parathion were the most frequent organophosphate pesticide detected in 100% and 62.5% of the samples with average concentrations of 25.20 and 47.48 μg kg-1, respectively. More research is needed to establish the background levels of pesticides in agricultural soils and their potential ecological and human health effects in this region. © 2014 Copyright © Taylor & Francis Group, LLC.
Mugica-Alvarez V.,Metropolitan Autonomous University |
Santiago-de la Rosa N.,Metropolitan Autonomous University |
Figueroa-Lara J.,Metropolitan Autonomous University |
Flores-Rodriguez J.,Metropolitan Autonomous University |
And 2 more authors.
Science of the Total Environment | Year: 2015
Sugarcane burning is an agricultural practice implemented to ease farm worker duties; nevertheless, as a consequence, tons of particles are emitted to the atmosphere. Additionally, during harvesting the sugar-mills operate the whole day emitting hundreds of tons of pollutants. Therefore, health risks to neighboring population should be a major governmental concern, leading first to identification and quantification of toxic compounds, such as polycyclic aromatic hydrocarbons (PAHs). In order to establish the magnitude of the problem, four sampling campaigns of PM10 and PM2.5 were carried out in this study, during harvesting and no-harvesting seasons in two municipalities of México, with different climatic and social conditions. Concentrations of PM10, PM2.5, and organic compounds were determined daily, followed by extraction, identification and quantification of the 17 EPA-established PAHs from all samples. The results showed that during harvest, the PM10 mass increased lightly in Chiapas, but approximately twice in Morelos, whereas total PAH concentrations increased twice and six times, respectively. The most abundant PAHs, namely: indene [1,2,3cd] pyrene, benzo[b]fluoranthene, benzo[a]pyrene and dibenzo [a,h] anthracene are composed of 5 or more aromatic rings. Of the total PAHs quantified, 44% to 52% corresponded to carcinogenic compounds, consequently, the overall carcinogenic potential increased twice or three times. Principal component analysis with varimax rotation was applied to source apportionment at each site, suggesting three different sources during harvesting: the combustion process in the sugar mill, sugarcane burning and vehicular emissions. The combustion markers for sugar mill are, BAA, BBF, BKF, BAP, IND and BGP, whereas for sugarcane burning were ANT, PHE, FLT and PYR. The results obtained indicate that processing and burning sugarcane are the main sources of the PAH levels measured, proving that the health risks are boosted during harvesting due to increases of PM and PAHs. © 2015 Elsevier B.V.