FIGURA 4 - uploaded by Gregorio Ángeles-Pérez
Content may be subject to copyright.
Correlación espacial L 12 (t) (Besag, 1977; Ripley, 1977) de Acacia tenciifolia con individuos a) juveniles y b) adultos de Pachycereus weberi en La Cañada del Zopilote, Guerrero.
Source publication
The aim of this study was to determine the population structure of Pachycereus weberi in Cañada del Zopilote (Buzzard Canyon), Guerrero, Mexico. An observation plot of 50 x 50 m (2,500 rrP) was established and divided into quadrats of 10 x 10 m to facilitate the field survey. All P. weberi individuals with height ≥ 0.10 m were tagged, and their tot...
Context in source publication
Context 1
... attempt was made to determine whether tree species associated with Pachycereus weberi showed a pattern of association with juveniles and adults. Figure 4 shows the spatial correlation between juveniles and adults of P. weberi and Acacia tenciifolia. An attraction pattern was observed between juveniles and the Acacia species at distances less than 3 m. ...
Citations
... The aggregated spatial distribution of L. graveolens is influenced by the slope; TC1 to TC4 had lower percentages of slope compared to TC5 (65 %). The aggregate distribution pattern of plants may be associated with topography (Linzaga-Román, Ángeles-Pérez, Catalán-Heverástico, & Hernández-De la Rosa, 2011) and may indicate interactions among individuals and between individuals with the environment(Linzaga-Román et al., 2011;Ruiz-Aquino, Valdez-Hernández, Romero-Manzanares, Manzano- Méndez, & Fuentes-López, 2015). Limitations in terms of seed dispersal distance can lead to an aggregate distribution pattern (Lara-Romero, de la Cruz, Escribano-Ávila,García-Fernández, & Iriondo, 2016) ...
Introduction: Oregano (Lippia graveolens H. B. K.) grows in semi-arid ecosystems. There is no information on the population dynamics of this species at the Tehuacán-Cuicatlán Biosphere Reserve (RBTC). Objective: To determine the vertical structure and spatial distribution of L. graveolens in five topographic conditions in the RBTC. Materials and methods: Ten sampling units were established in five topographic conditions (TC), where six plant height categories were defined. Density and structural variables were measured, from which IVI was obtained and population structure curves were constructed. The spatial distribution pattern was analyzed with the Ripley's transformed function (L (t)). Results and discussion: TC1 showed population curve type IV (low frequency in the first, third and fourth height categories, high in the second and fifth categories, and low in the rest) with lower density (100 plants•ha-1 ; 1.6 %) in category 6 (>251 cm), and higher density (1 840 plants•ha-1 ; 29 %) in category 4 (151 a 200 cm). For TC2 to TC5, the curve was V-type (low frequency in the first category, gradual increase up to the intermediate category, and gradual decrease in the rest) with lower density (20 plants•ha-1 ; 0.4 %) in category 6, and higher density (2 320 plants•ha-1 ; 51 %) in category 4 which also had the highest IVI (92.8 to 126.1). Spatial distribution was aggregated in TC1 to TC4 and randomized in TC5. Conclusions: Topographic conditions influenced the vertical structure and spatial distribution of oregano.
... The aggregated spatial distribution of L. graveolens is influenced by the slope; TC1 to TC4 had lower percentages of slope compared to TC5 (65 %). The aggregate distribution pattern of plants may be associated with topography (Linzaga-Román, Ángeles-Pérez, Catalán-Heverástico, & Hernández-De la Rosa, 2011) and may indicate interactions among individuals and between individuals with the environment(Linzaga-Román et al., 2011;Ruiz-Aquino, Valdez-Hernández, Romero-Manzanares, Manzano- Méndez, & Fuentes-López, 2015). Limitations in terms of seed dispersal distance can lead to an aggregate distribution pattern (Lara-Romero, de la Cruz, Escribano-Ávila,García-Fernández, & Iriondo, 2016) ...
Introduction:
Oregano (Lippia graveolens H. B. K.) grows in semi-arid ecosystems. There is no information on the population dynamics of this species at the Tehuacán-Cuicatlán Biosphere Reserve (RBTC).
Objective:
To determine the vertical structure and spatial distribution of L. graveolens in five topographic conditions in the RBTC.
Materials and methods:
Ten sampling units were established in five topographic conditions (TC), where six plant height categories were defined. Density and structural variables were measured, from which IVI was obtained and population structure curves were constructed. The spatial distribution pattern was analyzed with the Ripley's transformed function (L (t) ).
Results and discussion:
TC1 showed population curve type IV (low frequency in the first, third and fourth height categories, high in the second and fifth categories, and low in the rest) with lower density (100 plants∙ha⁻¹; 1.6 %) in category 6 (>251 cm), and higher density (1 840 plants∙ha⁻¹; 29 %) in category 4 (151 a 200 cm). For TC2 to TC5, the curve was V-type (low frequency in the first category, gradual increase up to the intermediate category, and gradual decrease in the rest) with lower density (20 plants∙ha⁻¹; 0.4 %) in category 6, and higher density (2 320 plants∙ha⁻¹; 51 %) in category 4 which also had the highest IVI (92.8 to 126.1). Spatial distribution was aggregated in TC1 to TC4 and randomized in TC5.
Conclusions:
Topographic conditions influenced the vertical structure and spatial distribution of oregano.
... Lo anterior coincide con lo señalado por Franklin y Rey (2007) Algunos autores (Rozas y Camarero, 2005;Linzaga-Román et al., 2011) proponen que un comportamiento tan variable en el patrón de distribución se explica por los factores topográficos del sitio. De tal manera que es factible plantear que la distribución de las especies en el ANP de Metzabok podría asociarse tanto con la heterogeneidad ambiental inducida por el relieve, como con los disturbios ocasionados en cada sitio, como lo sugieren Montañez et al. (2010) y Barreto-Silva et al. (2014) para algunas selvas tropicales de Colombia. ...
Se analizó el patrón de distribución y correlación espacial de las especies arbóreas a lo largo de un gradiente altitudinal en el Área Natural Protegida (ANP) Metzabok, Selva Lacandona, Chiapas. En cada estrato altitudinal (EA) se instaló una unidad de muestreo de 20 × 50 m, que fue dividida en 10 subunidades de muestreo (SUM) de 10 × 10 m, donde se registraron los fustales. En las SUM se delimitó un cuadro de 5 × 5 m para el registro de latizales, y en su interior se establecieron dos cuadros de 2 × 2 m para el reconocimiento de brinzales. La distribución espacial de fustales, latizales y brinzales se analizó con el índice de Morisita-Horn; mientras que, la distribución y correlación espacial de los fustales por categorías de altura (inferior, intermedia y superior) y EA se evaluó mediante la función univariada K(t) y bivariada K12 (t) de Ripley. El patrón espacial promedio de la clase fustal para las tres categorías de altura a lo largo del gradiente altitudinal fue agregado (), similar que en latizales y brinzales . La función K12 (t) indica que los EA 2, 3 y 5 de la categoría inferior-intermedia mostraron, tanto repulsión como atracción espacial, mientras las denominadas inferior-superior e intermedia-superior tuvieron un comportamiento de independencia y repulsión espacial, respectivamente. Estos hallazgos aportan bases para la implementación de estrategias silvícolas enfocadas a la conservación de las especies arbóreas presentes en el ANP Metzabok.
... Linzaga (2010) realizó un estudio demográfico de plántulas de P. weberi en el estado de Guerrero, en el cual encontró escaso reclutamiento de nuevos individuos a la población, esta misma situación fue identificada por Martínez-Peralta et al. (2010) para la comunidad de Dominguillo en el Valle de Tehuacán-Cuicatlán, dicho autor sugiere que deben existir procesos complejos en el reclutamiento y establecimiento de esta especie, situación que podría estar sucediendo con las poblaciones silvestres de Santo Domingo Tonalá. Es necesario llevar a cabo análisis en los cuales se pueda estimar la tasa de extracción, ya que la fuerte sobreexplotación, aunado al bajo reclutamiento, son factores que amenazan seriamente las poblaciones silvestres de P. weberi (Linzaga, 2010), y de otras cactáceas. En orden de importancia, el cultivo es la segunda forma de manejo que más se lleva a cabo, principalmente con especies de interés ornamental como las pertenecientes al género Mammillaria, y comercial como S. pruinosus y S. griseus, cuyos frutos, las pitayas, son comercializadas de manera local. ...
It was made a ethnobotanical study of succulent plants in Santo Domingo Tonala, Oaxaca. The field work consisted of monthly courses for a year, to places where there is presence of these plants; to learn about their use and traditional management, structured interviews (two events) were applied to 20 key employees; subsequently it conducted the analysis of the main ethnobotanical data using the ethnographic method of free listed index and value in use. They were recorded 44 species of useful succulent plants, including six botanical families: Cactaceae, Agavaceae, Nolinaceae, Crassulaceae, Euphorbiaceae and Fouquieriaceae; which stands Cactaceae, therefore the number of species as assigned applications. Of a total of 21 categories of use, the main ones were edible, ornamental and medicinal; while the main form of management is the collection of plants in the natural vegetation. Because of the wide variety of uses for the succulent plants are used, a group with great potential becomes, and as an alternative for sustainable use by the communities; however, it is necessary to conduct studies that provide information on cups extraction of the species and the current status of their populations. There is a crisis of loss of plant species and disappearance of knowledge about their use and management. In Santo Domingo Tonala a number of useful succulent plants identified, therefore, this region is a priority for designing strategies that contribute to the conservation of these vegetable resources and the rescue and assessment of traditional knowledge.
... By contrast, in the SU1 and SU3, Q. laurina which was the second importance value had clumped patterns, indicating that they are associated with a lower tree density and probably with the position of hierarchically subordinate species to the dominant species, occupying the spaces left free. The clumped pattern is due to specific topographic conditions or to a heterogeneous field (Condés, & Martínez, 1998;Linzaga-Román, Ángeles-Pérez, Catalán-Heverástico, & Hernández de la Rosa, 2011), leading to high variation in the distribution of light and soil nutrients. However, Figure 3 shows patterns of random distribution when analyzing the spatial distribution of Q. laurina and Q. crassifolia in each SU, indicating that the spatial distribution of each species is due to the relations of association between trees; to the different regeneration strategies, v. g. the asynchrony in producing acorns as a mechanism to reduce competition between sympatric species (Crawley & Long, 1995);vvvv to the dispersion of the species, v. g. acorns dispersed to reduce mortality result of predation (Pérez, Barrera, García, Cuevas-Reyes, & González-Rodríguez, 2013); and to silvicultural menor en la UM1, reflejando la dominancia de pocas especies. ...
The structure and diversity of pine-oak woodlands in Ixtlán de Juárez, Oaxaca, was analyzed using three sampling units (SU) of 50 x 50 m. The spatial distribution of trees with normal diameter ≥ 2.5 cm was determined. Dasometric variables were recorded; two indices of structural importance (the Relative Importance Value Index [RIVI] and the forest value index [FVI], and three diversity indices (Shannon-Wiener Entropy Index, effective number of diversity, and Sorensen index) were calculated. A total of 799 trees were recorded, belonging to 11 families and 19 species; the most abundant family was Fagaceae (628 individuals, four species). In SU1, the most important species was Quercus crassifolia (RIVI = 53; FVI = 57). The highest values of RIVI and FVI in SU2 were for Q. laurina (RIVI = 48, FVI = 63). In SU3, the most important species was Q. crassifolia (RIVI = 49, FVI = 62). The analysis of both species revealed random distribution in practically all distances. The aggregate pattern of tree species was attributed to regeneration strategies and silvicultural practices. Both species can coexist modifying the structural importance and horizontal distribution pattern.
... En cactáceas columnares, la fecundidad se incrementa con el tamaño (Esparza-Olguín et al. 2005), pues las estructuras reproductivas se desarrollan principalmente en la categoría de adultos. Con base en este estudio y lo observado por Linzaga-Román et al. (2011) se considera que los individuos de P. weberi en etapa reproductiva son los de más de 6 m de altura. Diferente a lo que señala Valiente-Banuet et al. (1997), acerca de que el periodo de floración de P. weberi en la Reserva de la Biósfera de Tehuacán-Cuicatlán es de noviembre a febrero-marzo y el de fructificación de febrero a marzo, en el presente estudio se observó que la floración se presentó en los meses de abril a junio y la fructificación en mayo y junio, futuros estudios podrían evaluar la causa de estas diferencias. ...
... Al igual que muchas especies de la familia Cactaceae Martínez Hernández & Pacheco 2000;Martínez-Mendoza & López 2000;Flores-Martínez et al. 2002;Larrea-Alcázar & Soriano 2008;Avendaño-Calvo 2007;Ramos-López 2007;Zenteno-Ruiz et al. 2009; Nova-Muñoz 2010), P. weberi muestra una distribución espacial agregada. Entre las posibilidades que explican esta distribución espacial, podría ser que estas especies hayan ocupado una mayor extensión en el pasado, o bien que ocupe sitios con características ambientales específicas (Valverde et al. 2004), debido a la alta variación en la distribución de los recursos ambientales en el sitio donde se encuentra la especie (Valiente-Banuet & Ezcurra 1991;Larrea-Alcázar & Soriano 2008;Zenteno-Ruiz et al. 2009;Linzaga-Román et al. 2011). Un aspecto fundamental para el mantenimiento de estas poblaciones regionales sería la dispersión de semillas entre las distintas poblaciones locales o la posible colonización de nuevos sitios dada la elevada probabilidad de extinción de algunas especies locales (Valverde et al. 2004). ...
Resumen Pachycereus weberi es una cactácea columnar de gran importancia económica, ecológica y cultural representativa de la Reserva de la Biosfera Tehuacán-Cuicatlán. El estudio de sus atributos demográficos y reproductivos contribuirá tanto a su conservación ex situ como a la de sus poblaciones silvestres. Las semillas de P. weberi mantienen su viabilidad en el transcurso de un año, germinando en un 96% a los trece meses de edad. La plantas nodrizas son elementos muy importantes en el establecimiento de nuevos individuos; bajo la sombra de Acacia cochliacantha se registró una sobrevivencia de plántulas del 54%, mientras que a cielo abierto todas murieron. Las estructuras reproductivas se desarrollan en individuos de más de 6 m de altura, por lo que son los sexualmente reproductivos. Esta especie muestra una distribución espacial agregada en la zona de estudio. Abstract Pachycereus weberi is a columnar cactus economic, ecological and cultural important, representative of the Biosphere Reserve Tehuacán-Cuicatlán. In this study were analyzed some demographic and reproductive attributes to contribute to ex situ conservation as conservation of wild populations. Germination experiments show that the seeds of P. weberi did not lose viability as thirteen months old seeds germinated 96%. The nurse plants are very important elements in the establishment of new individuals of this species, as in the shade of Acacia cochliacantha one seedling survival of 54% was recorded, while in the opening all seedlings died. The reproductive structures develop in individuals over 6 m high, so are the sexually reproductive. This species shows a clumped spatial distribution in the study area.
