Despite restoration efforts, Mexico loses on average 500 000 ha of temperate forests annually, releasing the carbon stored in plant tissues, leaf litter, and soils into the atmosphere. Much of the temperate forests of Mexico grow on volcanic soils (Andosols), which cover approximately 1.2% of the country’s area. However, little information is available on how much carbon is stored in soil, leaf litter, and arboreal components of these systems. Therefore, the objective of this study was to determine organic carbon concentration in trees, litter, and soil in “El Faro” Protected Natural Area in Tlalmanalco, Mexico State. This research selected eight study sites under four tree-cover categories: Cupressus-Pinus, Pinus-Quercus, Quercus-Pinus and Quercus, and determined species and normal diameter (DN) of trees with DN larger than 10 cm, samples of leaf litter and soil were collected at a depth of 0-20 cm. Soil organic carbon (SOC) concentration was determined in the laboratory in an elemental analyzer, as well as bulk density, porosity, and rock volume. Total carbon stored by trees was estimated using species-specific allometric formulas. The average total carbon content was 185.34 Mg ha-1, with an overall average of 56.40 Mg ha-1 in trees, 44.91 Mg ha-1 in leaf litter, and 84.03 Mg ha-1 in soil. The tree cover storing the most carbon in vegetation was Pinus-Quercus, with 71.74 Mg ha-1, and across all the study sites a positive correlation was recorded between total Quercus tree biomass and SOC. This result was probably due to faster accumulation and decomposition of Quercus leaf litter compared to pine needles. Based on the estimates of this study, 50 ha of El Faro protected natural area stored a total of 9267 Mg of carbon that could be released if the area were deforested, evidencing the importance of its conservation.

Soil quality in volcanic soils in a forest biosphere reserve in Mexico | Yaselda Chavarin-Pineda, Eduardo C. Reynoso, Eduardo Torres, Gerardo Cruz-Flores, Ma. Guadalupe Tenorio-Arvide, Gladys Linares-Fleites, Miguel Ángel Valera-Pérez | Agricultural Journals

The wide range of water-related problems, with their diverse implications for living beings and the environment, is an urgent issue to which both decision-makers at various levels and academia, as a generator and mobiliser of relevant and valuable knowledge for the community, must dedicate themselves. In Resolution 64/292, the United Nations General Assembly explicitly recognised the Human Right to Safe Drinking Water and Sanitation (HRWSS), of July 28th., 2010. It calls upon States and international organisations to provide financial resources, capacity building and technology transfer to help provide accessible and affordable drinking water supply and sanitation for all. The primary objective of this article is raise awareness among the general population of the risks and conflicts caused by weak water governance by providing information, through the methodology of meta-analysis, in the quest to educate and deepen the conservation and reutilisation of water, not only as a limited natural resource but also as a central part of maintaining peace in an increasingly water-thirsty world where powerful interests continue the demand for and consumption of this precious liquid, despite the populations themselves and the scientific warnings on the subject. Las múltiples y variadas problemáticas en torno al agua, con sus implicaciones para los seres vivos y el ambiente, es un aspecto urgente al que deben dedicarse, tanto tomadores de decisión en los diversos niveles, como la academia en tanto generadora y movilizadora de conocimientos pertinentes y valiosos para la comunidad. En la Resolución 64/292, la Asamblea General de las Naciones Unidas reconoció explícitamente El Derecho Humano al Agua Potable y al Saneamiento (DHAS), 28 de julio 2010. En esta se exhorta a los Estados y organizaciones internacionales a proporcionar recursos financieros, propiciar la capacitación y la transferencia de tecnología para ayudar a disponer de un suministro de agua potable y saneamiento accesible y asequible para todos. El primordial objetivo de este artículo es que la población se concientice en general sobre los riesgos y conflictos que provoca la insuficiente gobernanza del recurso hídrico, aportando información, por medio de la metodología del meta-análisis en la búsqueda de educar y profundizar en la conservación y reutilización del agua, vista esta no solo como un recurso natural escaso, sino como un elemento central en el mantenimiento de la paz en un mundo cada vez más sediento donde los grandes intereses continúan la demanda y el alto consumo del vital líquido, aun en contra de las poblaciones mismas y de las alertas que la ciencia nos brinda al respecto. As muitas e variadas questões que envolvem a água, com suas implicações para os seres vivos e o meio ambiente, são um aspecto urgente ao qual devem se dedicar tanto os tomadores de decisão em vários níveis quanto o meio acadêmico, como gerador e mobilizador de conhecimento relevante e valioso para a comunidade. Na Resolução 64/292, a Assembleia Geral das Nações Unidas reconheceu explicitamente o Direito Humano à Água Potável Segura e ao Saneamento (HRWSS), de 28 de julho de 2010 Ela exorta os Estados e as organizações internacionais a fornecerem recursos financeiros, capacitação e transferência de tecnologia para ajudar a fornecer água potável e saneamento acessíveis e baratos para todos. O principal objetivo deste artigo é ajudar a conscientizar a população em geral sobre os riscos e conflitos causados pela governança insuficiente da água, fornecendo informações por meio da metodologia de meta-análise na busca de educar e aprofundar a conservação e a reutilização da água, Essa é vista não apenas como um recurso natural escasso, mas também como um elemento central para a manutenção da paz em um mundo cada vez mais sedento, onde os grandes interesses continuam a demanda e o alto consumo do líquido vital, mesmo contra as próprias populações e os alertas que a ciência fornece a esse respeito.

Heavy metals in urban dust, derived from anthropogenic activities and natural sources, are considered potentially toxic elements for human health. The city of Puebla, located in Central Mexico, is one of the ten largest metropolitan cities in Mexico. Near this city is the Popocatépetl volcano, which contributes heavy metals through the emission of ash. The objectives of this study were to evaluate heavy metal contamination in urban dust and volcanic ash from the city of Puebla, and to determine the associated human health risks. Heavy metals were analyzed using an XRF spectrometer. The level of contamination was established according to the contamination factor, the geoaccumulation index and the contaminant load index. Furthermore, non-carcinogenic risk indices (HIs) were calculated to evaluate the health risk. The results revealed the presence of 18 elements (Ca, Cr, Cu, Fe, K, Mn, Nb, Ni, Pb, Rb, Sb, Sn, Sr, Ti, Y, V, Zn and Zr), with the highest concentrations found for most in urban dust samples, while Rb, Ca and K showed higher concentrations in ash samples. High levels of Sb and Sn contamination were found in 90 to 100% of the dust and ash samples, while Cr, Cu, Ni, Pb and Zn showed considerable levels of contamination in 60 to 90% of the samples. According to the US EPA thresholds, the health risk assessment indicated safe levels (HI < 0.25) for Cu, Fe, Mn, Ni, Pb, Sn, V and Zn in the urban dust and volcanic ash samples, while some of the samples exceeded the safety threshold (HI > 1) for Cr and Sb with respect to the child population in the city of Puebla. These results must be taken into consideration by environmental and government authorities, and the degree of pollution should be reduced accordingly.

The Megalopolis of the Mexico Valley Metropolitan Area (MZMVM) is one of the most polluted regions in the country. With its high population density and industrial activity, the MZMVM has recurrent ozone pollution episodes due to meteorological conditions and emissions of precursors such as nitrogen oxides and volatile organic compounds. The study of ozone is crucial due to its severe effects on human health, vegetation degradation, and air quality. The methodology used included the analysis of the air quality index and the occurrence of environmental contingencies from 2001 to 2022. Data from 80 monitoring stations distributed in the seven states constituting the MZMVM were used. The data were validated and processed according to Mexican and international standards. The results show an improvement in air quality in Mexico City and the State of Mexico, while a deterioration was observed in Hidalgo and Morelos during the study period. Although environmental emergencies due to ozone are now less frequent, they still represent a significant risk to public health and should be analyzed. This analysis highlights the importance of implementing stricter and more sustainable policies to reduce emissions of ozone precursors and protect both human health and the environment.

En un mundo que exige una producción de alimentos cada vez más intensa, los suelos enfrentan un grave proceso de degradación. Esto se debe, en gran medida, a prácticas agrícolas cuyo único objetivo es maximizar el rendimiento a corto plazo. El cambio de uso de suelo de forestal a agrícola provoca fragmentación, pérdida de biodiversidad, degradación del suelo y erosión. Esta última impacta negativamente la producción de alimentos y agua. Ante esta situación, ha sido necesario reivindicar los sistemas agrícolas tradicionales del Altiplano Central Mexicano. Sus técnicas, practicadas desde la época prehispánica, representan una alternativa para el desarrollo de una agricultura sostenible. Uno de estos sistemas de uso tradicional es el sistema metepantle, cuyo elemento principal, el maguey pulquero (Agave salmiana), en combinación con otros elementos como árboles frutales y maderables, zonas de cultivo (sistema milpa, cebada, etc.), zanjas y jagüeyes, crea un sistema complejo que proporciona múltiples beneficios ecológicos, sociales y económicos. En este contexto, el objetivo de este artículo es impulsar y divulgar el conocimiento sobre los beneficios que este sistema agroecológico proporciona, lo cual permitirá reconocer, por parte de la sociedad y las personas involucradas, la importancia de su restablecimiento.