En la interfase ciudad-comunidades rurales del área metropolitana del Valle de Puebla se tienen establecidas siete áreas naturales protegidas periurbanas. El objetivo de esta investigación fue tener ...un diagnóstico exploratorio de su condición actual y de los factores que inciden en su pérdida territorial y deterioro ecológico. Estas áreas no están funcionando como estrategias de conservación debido a que carecen de una delimitación espacial precisa y de un plan de manejo, son desconocidas por la mayoría de los habitantes del área, carecen de un presupuesto para su gestión, hay venta de tierras y persisten las actividades productivas y extractivas.
In the city-rural communities interface of the Puebla Valley seven periurban protected natural areas have been established. The objective of this investigation was to have an exploratory diagnosis of their current status and of the factors that affect their territorial loss and its ecological deterioration. These areas are not functioning as conservation strategies, because they lack a precise spatial delimitation and a management plan, they are unknown to most of the inhabitants of the area, they lack a budget for their management, the sale of lands and the productive and extractive activities.
Background. Tropical dry forests (TDF) provide numerous environmental services to its residents; this has led them to be humanized landscapes subjected to chronic disturbance with a high risk of ...disappearing. Research question. To establish the relationship of vegetation structure and composition of a chronically disturbed TDF, with some environmental factors and the intensity of agricultural land use. Study site and period of research. Our study was conducted during six months (July through November) in the TDF of the community of San Nicolas Zoyatlan (Guerrero, Mexico); a territory with a history of over 500 years of agricultural use. This use has led to a complex mosaic of vegetation fragments. Methods. A selection of 36 fragments was studied to determine vegetation structure and composition as well as environmental factors. Representative plants from sampled areas were collected. Data gathered was explored with regression and multivariate statistical analysis techniques. Results. 59 families, 178 genera and 279 species were recorded. Species richness varied widely among fragments, in general with a low dominance and high turnover of species. Slope was the only factor that showed a solid relationship with vegetation variables. Three groups of fragments were established and the statistical differences between them were explained by the duration of fallow. The fragments with longer fallow period showed the best conditions in vegetation variables and 66.9% of the species were found in them. Conclusions. Composition and structure of vegetation were related to intensity of agricultural land use. Although there is a process of impoverishment, vegetation dynamics involving species of the Fabaceae, Asteraceae and Burseraceae families show a potential for their use in the environmental restoration of Zoyatlan.
Antecedentes: Los bosques tropicales secos (BTS) aportan numerosos servicios ambientales a sus habitantes, esto los ha llevado a ser paisajes humanizados sujetos a disturbio crónico con riesgo de desaparecer. Pregunta: ¿Cuál es la relación de la composición y estructura de la vegetación de un BTS sujeto a disturbio crónico, con algunos factores del medio físico y la intensidad de uso agrícola del suelo? Sitio de estudio y fecha: El estudio se realizó en la comunidad de San Nicolás Zoyatlan (Guerrero, México) durante seis meses (junio-noviembre). Este territorio cuenta con más de 500 años de uso agropecuario, lo que ha propiciado un complejo mosaico de fragmentos de vegetación. Métodos: Se muestrearon 36 fragmentos para determinar la composición y estructura de la vegetación y los factores ambientales. Se recolectó y herborizó el material botánico representativo de las áreas muestreadas. Utilizando análisis de regresión y técnicas multivariadas se establecieron, tanto relaciones entre la vegetación y los factores ambientales como grupos específicos de fragmentos. Resultados: Se registraron 59 familias, 178 géneros y 279 especies. Entre fragmentos la riqueza específica varío ampliamente presentándose una dominancia baja y un alto recambio de especies. Únicamente la pendiente mostró una relación consistente con las variables de vegetación. Se obtuvieron tres grupos de fragmentos cuyas diferencias estadísticas se explicaron por los periodos de descanso agrícola; las zonas con mayor tiempo de barbecho presentaron 66.9 % de las especies y las mejores condiciones en las variables de vegetación. Conclusiones: La composición y estructura de la vegetación del BTS estuvo relacionada con la intensidad de uso agrícola del suelo. Aunque se presenta un proceso de empobrecimiento de la vegetación, existe una dinámica en la que participan especies de las familias Fabaceae, Asteraceae y Burseraceae, con potencial para utilizarse en la restauración ambiental de Zoyatlan.
In Latin America, indigenous communities have been distinguished by continuous marginalization and degradation of their social-ecological systems (SES), and this is the case of San Nicolás Zoyatlan ...(Guerrero, Mexico). With the purpose of establishing restoration strategies, we conducted an in situ diagnosis to assess the current condition of the community and its disturbance factors. We combined methods of environmental and social sciences to analyze, in diachronic and synchronic contexts, how the SES's natural resources are used. Results indicate that the chronic ecological disturbance of the SES and agrarian conflicts have contributed to the degradation of vegetation and soil. Thus, vegetation is impoverished, with secondary tropical deciduous forest (TDF) shrub vegetation predominating, and the risk of soil degradation is high, despite the inhabitants' knowledge and appreciation of this resource. To reverse degradation, we defined and established rehabilitation practices with the involvement of inhabitants. These comprised agroforestry systems (AFSs) and plantations (PLs) on community lands, using 18 native TDF species selected on the basis of local preferences. Our ongoing assessment indicates that after more than a decade, the AFSs and PLs are maintained and managed by the people, as reflected in the current size of plants whose inputs contribute to improve physical and chemical soil characteristics, such as soil aggregate formation, cation exchange capacity and organic matter content. However, we concluded that we need to confirm whether the ecosystem processes and environmental services are recovered and maintained over time, in addition to determining how they have influenced and will continue to influence the socioeconomic factors involved in maintaining rehabilitation practices.
The incorporation of ethnopedological knowledge in soil science and the inclusion of indigenous communities as beneficiaries of the agricultural technology are indispensable premises to make a better ...use of soil. However, to achieve this, it is necessary to have clearer communication and understanding between peasants and soil specialists. This paper contributes to the understanding of the way in which the ethnopedologic knowledge of the community of Zoyatlán (Mexico) has been used in making decisions on soil management and production. It also proposes a methodological alternative that will contribute to the communication among land users and soil specialists. Our results show that Zoyatlán peasants identify seven soil types grouped into four classes according to their agricultural suitability. These classes are determined by distinctive land properties that enclose six agronomic characteristics of the topsoil and four specific characteristics of the work area. Based on this criteria, we designed a parametric method assuming that the agricultural suitability of the land is determined by several characteristics of the topsoil; among them topsoil thickness was outstanding. This characteristic was susceptible to being represented parametrically by numerical values (obtained from a mathematical model), which is a single numerical expression of topsoil thickness performance. The application of this methodology provided information that is useful and can easily be interpreted by both the peasants and the soil specialists. Furthermore, this information can be represented at different cartographic scales.
A pesar del profundo deterioro de los ecosistemas naturales mexicanos y de los efectos negativos que éstos generan en la calidad de vida de la población, la restauración ambiental no se ha convertido ...en una política pública prioritaria. Acciones de restauración como la reforestación y el mejoramiento de suelos han sido impulsadas desde principios del siglo XX. Sin embargo, la prioridad se ubicó en la forestación de áreas verdes urbanas y zonas conurbadas y en la recuperación de suelos agrícolas. No fue sino hasta la década de los años noventa cuando se incluyó una visión más integral de la restauración. Por ejemplo, en cuanto a la reforestación, se priorizaron áreas compactas rurales con la introducción de especies nativas. Si bien esto constituye un avance importante, se sigue poniendo un énfasis excesivo en la producción y siembra de plantas, pero no en la supervivencia de las mismas en el largo plazo y la consolidación del área reforestada. Otros programas importantes son la recuperación de especies prioritarias en peligro de extinción, la eliminación de especies exóticas y la recuperación de tierras degradadas en regiones prioritarias como el trópico húmedo, entre otros. Hay avances signifi c ativos en la platafo rma programática, en la asignación de recursos económicos y en la gestión institucional, pero falta aún consolidar un marco normativo adecuado y armónico, e incrementar los esfuerzos para la formación de cuadros técnicos y científicos con una visión integral e interdisciplinaria que influyan en la formulación de nuevas políticas públicas para la restauración ambiental
La determinación de cambios en la cubierta terrestre (CT) es importante para entender la dinámica de los ecosistemas. En este estudio se analizaron los cambios espaciales y temporales en el municipio ...de Ixtacamaxtitlán, Puebla durante el periodo 2000-2015, utilizando los mapas globales de la Agencia Espacial Europea ESA-CCI-LC. Para ello, se determinó la matriz de cambios, la tasa anual de cambio y la probabilidad de permanencia, así como la precisión del mapa de CT 2015. Los resultados indican que las pérdidas se concentraron en las coberturas arboladas y pastizales (0.27% y 8.83%, respectivamente), mientras que las ganancias se dieron en tierras de cultivo y zonas urbanas (6.9% y 8.11%, respectivamente). La mayoría de los cambios se observaron en las zonas de fácil acceso ubicadas en la porción centro-norte del municipio. De las 1962 ha que presentaron cambios entre categorías, en 87.4% el cambio fue negativo y en 12.6% fue positivo, destacando la transición de pastizales y superficies arboladas hacia tierras de cultivo, causadas por diversos procesos socioeconómicos presentes en la zona como marginación, migración, acceso a programas gubernamentales, expansión de áreas agrícolas y diversificación de cultivo. El mapa de CT 2015 mostró una alta precisión a escala subnacional (85.64%) lo que revela que este conjunto de datos es confiable para el estudio de las transformaciones en el territorio.
High prevalence of diabetes has been reported in the Americas, but no comprehensive analysis of diabetes burden and related factors for the region is available. We aimed to describe the burden of ...type 1 and type 2 diabetes and that of hyperglycaemia in the Americas from 1990 to 2019.
We used estimates from GBD 2019 to evaluate the burden of diabetes in adults aged 20 years or older and high fasting plasma glucose in adults aged 25 years or older in the 39 countries and territories of the six regions in the Americas from 1990 to 2019. The main source to estimate the mortality attributable to diabetes and to chronic kidney disease due to diabetes was vital registration. Mortality due to overall diabetes (ie, diabetes and diabetes due to chronic kidney disease) was estimated using the Cause of Death Ensemble model. Years of life lost (YLLs) were calculated as the number of deaths multiplied by standard life expectancy at the age that the death occurred, years lived with disability (YLDs) were estimated based on the prevalence and severity of complications of diabetes. Disability-adjusted life-years (DALYs) were estimated as a sum of YLDs and YLLs. We assessed the association of diabetes burden with the level of development of a country (according to the Socio-demographic Index), health-care access and quality (estimated with the Healthcare Access and Quality Index), and diabetes prevalence. We also calculated the population attributable fraction (PAF) of diabetes burden due to each of its risk factors. We report the 95% uncertainty intervals for all estimates.
In 2019, an estimated total of 409 000 (95% uncertainty interval 373 000–443 000) adults aged 20 years or older in the Americas died from diabetes, which represented 5·9% of all deaths. Diabetes was responsible for 2266 (1930–2649) crude DALYs per 100 000 adults in the Americas, and high fasting plasma glucose for 4401 DALYs (3685–5265) per 100 000 adults, with large variation across regions. DALYs were mostly due to type 2 diabetes and distribution was heterogeneous, being highest in central Latin America and the Caribbean and lowest in high-income North America and southern Latin America. Between 1990 and 2019, age-standardised DALYs due to type 2 diabetes increased 27·4% (22·0–32·5). This increase was particularly high in Andean Latin America and high-income North America. Burden for both type 1 and type 2 diabetes across countries increased with higher diabetes prevalence and decreased with greater Socio-demographic and Healthcare Access and Quality Indices. Main risk factors for the burden were high BMI, with a PAF of 63·2% and dietary risks, with a PAF of 27·5%. The fraction of burden due to disability has increased since 1990 and now represents nearly half of the overall burden in 2019.
The burden of diabetes in the Americas is large, increasing, heterogeneous, and expanding. To confront the rising burden, population-based interventions aimed to reduce type 2 diabetes risk and strengthening health systems to provide effective and cost-efficient care for those affected are mandatory.
Bill & Melinda Gates Foundation.
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