Structure and tree diversity of secondary dry tropical forests in the Sierra de Huautla Biosphere Reserve, Morelos

"Se estudió la recuperación en riqueza, composición, estructura y diversidad arbórea en 3 condiciones de bosque tropical caducifolio secundario con diferente tiempo de abandono (C35, C45 y C65 años) en el sureste del estado de Morelos. En cada condición se establecieron 3 unidades de muestreo de 50 × 50 m (2,500 m2) y se midieron a todos los individuos ≥ 2.5 cm de diámetro normal (DN). En total se registraron 2,791 individuos, pertenecientes a 79 especies, 53 géneros y 30 familias. Fabaceae fue la familia con el mayor número de especies e individuos. C45 presentó la mayor riqueza de especies (57), seguida de C35 (48) y C65 (43). Las condiciones fueron diferentes (p < 0.0001) en área basal, altura total, DN y cobertura de copa. Las especies con mayores índices relativos de valor de importancia (IVIR) y de valor forestal (IVFR) fueron Pachycereus grandis (IVIR = 22.6, IVFR = 28.7), Amphipterygium adstringens (IVIR = 20.9, IVFR = 17.0), Lysiloma divaricatum (IVIR = 11.2, IVFR = 18.9) y Quercus glaucoides (IVIR = 10.5, IVFR = 13.1). Se encontraron diferencias altamente significativas (p < 0.001) entre condiciones de abandono para la heterogeneidad (Shannon-Wiener: H´), y valores significativamente (p < 0.05) mayores en C65 para el recíproco de Simpson (1/D), así como en C35 y C45 para los índices de Margalef (DMG) y α de Fisher (S). La semejanza florística (Sorensen: Is) fue máxima entre condiciones con menor tiempo de abandono (72%) y mínima con la condición de mayor tiempo (54%). El procedimiento de permutación de respuesta múltiple indicó diferencias significativas (p < 0.05) en la composición de especies entre condiciones tempranas (C35 y C45) y tardías (C65). Estos resultados explican el proceso de la sucesión secundaria en los bosques tropicales caducifolios del área de estudio y dan elementos para efectuar una mejor planificación de las actividades conducentes a su conservación.""The recovery in richness, composition, structure and tree diversity was studied in three conditions of secondary tropical deciduous forest with different time of abandonment (C35, C45 and C65 years) in the southeast of the state of Morelos. In each condition, three plots of 50 × 50 m (2,500 m2) were established and all individuals ≥ 2.5 cm of normal diameter (ND) were measured. In total, 2,791 individuals belonging to 79 species, 53 genera and 30 families were registered. Fabaceae was the family with the largest number of species and individuals. C45 had the highest species richness (57), followed by C35 (48) and C65 (43). The conditions were different (p < 0.0001) in basal area, total height, ND and crown coverage. The species with the highest relative value of importance (IVIR) and forest value (IVFR) were Pachycereus grandis (IVIR = 22.6, IVFR = 28.7), Amphipterygium adstringens (IVIR = 20.9, IVFR = 17.0), Lysiloma divaricatum (IVIR =11.2, IVFR = 18.9) and Quercus glaucoides (IVIR = 10.5, IVFR = 13.1). High significant differences (p < 0.001) between abandonment conditions were found for heterogeneity (Shannon-Wiener: H’), and highest significant values (p < 0.05) for Simpson reciprocal index (1/D) in C65, as well as to Margalef (DMG) and Fisher’s α (S) indexes in C35 and C45. The floristic similarity (Sorensen: Is) was highest among conditions with less time of abandonment (72%) and minimum with the condition of greater time (54%). The multiple response permutation procedure indicated significant differences (p < 0.05) in the species composition between early (C35 and C45) and late (C65) conditions. These results explain the process of secondary succession in the tropical deciduous forests of the study area and provide elements for improve planning of the activities leading to its conservation.

Diferencias sociales y de conocimiento en niños de educación básica en comunidades del río Amacuzac, Morelos

El objetivo del artículo es estimar estadísticamente, con un enfoque cualitativo, el conocimiento sobre temas de educación ambiental de estudiantes de primaria en cuatro comunidades del río Amacuzac, antes y después de asistir a un taller sobre uso sustentable, manejo y conservación del agua y del ecosistema ripario, elaborado con base en materiales educativos de varias instituciones. Se aplicaron cuestionarios, cuyas respuestas reflejan las percepciones de los niños sobre el tema. Los resultados evidencian las diferencias significativas de conocimiento y aprendizaje entre las comunidades; también las capacidades para asimilar información nueva y retenerla. Se obtuvo un diagnóstico claro de los saberes y experiencias previas o iniciales de los asistentes. Esto es importante, porque los programas de educación ambiental difundidos y aplicados en el país suelen ser los mismos, pero la población es heterogénea por lo que es relevante incluir estas variables en el análisis, cuando se comparan las poblaciones

Construir sociedades comprometidas con el entorno natural: educación ambiental en niños del sur de Morelos, México

Con el objetivo de fortalecer programas educativos en Morelos, México, aquí se analizan las percepciones y los conocimientos que tienen sobre el medio ambiente los niños y los profesores de las escuelas rurales y urbanas del sur del estado. Con la aplicación de cuestionarios fue posible identificar los factores que inciden tanto en la forma en que ellos perciben el ambiente, como en la que adquieren conocimientos sobre él. La mayoría de los niños rurales desconoce la Reserva de la Biosfera Sierra de Huautla, a pesar de vivir en ella, y también el deterioro ambiental, lo que contrasta con los niños urbanos. Estos conocimientos están relacionados con el lugar donde viven, y con la sensibilidad de los profesores, quienes tienen gran influencia en las actitudes de sus alumnos, por lo que deben emplear estrategias divertidas y significativas que los motiven a descubrir y cuidar el entorno. Es fundamental la participación de instituciones académicas, gubernamentales y privadas, así como de los padres de familia, para generar una sensibilización integral sobre el medio ambiente en la sociedad

Analysis of thermodynamic parameters of binding of trypsin inhibitors with isothermal titration calorimetry

BACKGROUND: Worldwide, mestizo communities’s ethnobotanical knowledge has been poorly studied. Based on a mestizo group in Mexico, this study assesses a) the use value (UV) of the local flora, b) gendered differences in plant species, and c) the association between socio-economic variables and ethnobotanical knowledge. METHODS: To assess the degree of knowledge of plant resources, we conducted 41 interviews collecting information on knowledge of local plant resources and the socio-economic situation of the informant. We also collected free listings of useful plants by category of use to identify the UV of each species. With the support of key informants, we photographed and collected the plant material recorded during the interviews and free listings on five different habitats. Paired t-tests and a Wilcoxon signed rank test were used to determine differences in the number of species known by men and women. Differences in distribution were analyzed by means of the Shapiro–Wilk’s W normality tests. To determine the association of socio-economic factors and ethnobotanical knowledge, we used a non-metric multidimensional scaling analysis (NMDS). RESULTS: Informants listed 185 species. Medicinal plants constituted the most diverse group (90 species). Tropical deciduous forest is the habitat that concentrates the highest proportion of plant resources (80 species). The use-values were classified into three groups: A (4–6 UV; three species), B (0.35-1.37 UV; 39 species) and C (0–0.29 UV; 143 species). High-quality wood species and those associated to religious ceremonies had the highest UV. Women’s and men’s knowledge of plant species showed statistically significant differences at the interspecific and the intracategorical levels (Student’s test, T15 = 4.8, p < 0.001). Occupation, gender and age were statistically significant associated to ethnobotanical knowledge (p < 0.05), whereas income, education level, and place of origin were not. CONCLUSION: This research improves our understanding of the socio-economic activities associated with the intracultural distribution of ethnobotanical knowledge among mestizo Mexican communities. It also provides information on plant resources and habitats and how local peasants value them. This information could help in the development of proposals to improve biocultural conservation and strengthen traditional knowledge systems for effective forest management

Factors affecting ethnobotanical knowledge in a mestizo community of the Sierra de Huautla Biosphere Reserve, Mexico

Background: worldwide, mestizo communities's ethnobotanical knowledge has been poorly studied. Based on a mestizo group in Mexico, this study assesses a) the use value (UV) of the local flora, b) gendered differences in plant species, and c) the association between socio-economic variables and ethnobotanical knowledge. - Methods: to assess the degree of knowledge of plant resources, we conducted 41 interviews collecting information on knowledge of local plant resources and the socio-economic situation of the informant. We also collected free listings of useful plants by category of use to identify the UV of each species. With the support of key informants, we photographed and collected the plant material recorded during the interviews and free listings on five different habitats. Paired t-tests and a Wilcoxon signed rank test were used to determine differences in the number of species known by men and women. Differences in distribution were analyzed by means of the Shapiro-Wilk's W normality tests. To determine the association of socio-economic factors and ethnobotanical knowledge, we used a non-metric multidimensional scaling analysis (NMDS). - Results: informants listed 185 species. Medicinal plants constituted the most diverse group (90 species). Tropical deciduous forest is the habitat that concentrates the highest proportion of plant resources (80 species). The use-values were classified into three groups: A (4-6 UV; three species), B (0.35-1.37 UV; 39 species) and C (0-0.29 UV; 143 species). High-quality wood species and those associated to religious ceremonies had the highest UV. Women's and men's knowledge of plant species showed statistically significant differences at the interspecific and the intracategorical levels (Student's test, T15 = 4.8, p < 0.001). Occupation, gender and age were statistically significant associated to ethnobotanical knowledge (p < 0.05), whereas income, education level, and place of origin were not. - Conclusion: this research improves our understanding of the socio-economic activities associated with the intracultural distribution of ethnobotanical knowledge among mestizo Mexican communities. It also provides information on plant resources and habitats and how local peasants value them. This information could help in the development of proposals to improve biocultural conservation and strengthen traditional knowledge systems for effective forest management

Sustaining Medicinal Barks: Survival and Bark Regeneration of <i>Amphipterygium adstringens</i> (Anacardiaceae), a Tropical Tree under Experimental Debarking

Commercial harvests can threaten tree species harvested for their bark. Amphipterygium adstringens is a dioecious tree, endemic to the tropical dry forests of Mexico, where it is intensively harvested for its medicinal bark. Limited information hinders developing sustainable management strategies for A. adstringens. We assessed bark regeneration for male and female trees, and evaluated the effect of tree sex and diameter, debarking treatments and cutting seasons on bark regeneration and tree survival rates. Bark regeneration was higher for wet season harvested trees (vs. dry), regardless of their sex. Bark regeneration was higher on female than on male trees. There were significant interactions of harvest season, harvest treatment and tree sex diameter on bark regeneration and survival. Overall, the highest bark regeneration rates occurred in female trees with ≥20.1 cm diameter that were wet season harvested with a 50% debarking intensity. Consequently, wet season and intermediate intensity harvests appear to foster sound management, but we recommend against targeting exclusively a single demographic group (i.e., large female trees) due to potential negative impacts on species demography and bark supply. A grounded strategy for sustaining bark harvest would also need to take into account relevant aspects of local socio-ecological context, including harvest interactions with other land uses

Sustaining Medicinal Barks: Survival and Bark Regeneration of Amphipterygium adstringens (Anacardiaceae), a Tropical Tree under Experimental Debarking

Commercial harvests can threaten tree species harvested for their bark. Amphipterygium adstringens is a dioecious tree, endemic to the tropical dry forests of Mexico, where it is intensively harvested for its medicinal bark. Limited information hinders developing sustainable management strategies for A. adstringens. We assessed bark regeneration for male and female trees, and evaluated the effect of tree sex and diameter, debarking treatments and cutting seasons on bark regeneration and tree survival rates. Bark regeneration was higher for wet season harvested trees (vs. dry), regardless of their sex. Bark regeneration was higher on female than on male trees. There were significant interactions of harvest season, harvest treatment and tree sex diameter on bark regeneration and survival. Overall, the highest bark regeneration rates occurred in female trees with ≥20.1 cm diameter that were wet season harvested with a 50% debarking intensity. Consequently, wet season and intermediate intensity harvests appear to foster sound management, but we recommend against targeting exclusively a single demographic group (i.e., large female trees) due to potential negative impacts on species demography and bark supply. A grounded strategy for sustaining bark harvest would also need to take into account relevant aspects of local socio-ecological context, including harvest interactions with other land uses