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Effects of sample plot size and GPS location errors on aboveground biomass estimates from LiDAR in tropical dry forests

JOSE LUIS HERNANDEZ STEFANONI GABRIELA REYES PALOMEQUE MIGUEL ANGEL CASTILLO SANTIAGO STEPHANIE PATRICIA GEORGE CHACON ASTRID HELENA HUECHACONA RUIZ Fernando de Jesús Tun Dzul DINOSCA DULMARY RONDON RIVERA JUAN MANUEL DUPUY RADA (2018)

Accurate estimates of above ground biomass (AGB) are needed for monitoring carbon in tropical forests. LiDAR data can provide precise AGB estimations because it can capture the horizontal and vertical structure of vegetation. However, the accuracy of AGB estimations from LiDAR is affected by a co-registration error between LiDAR data and field plots resulting in spatial discrepancies between LiDAR and field plot data. Here, we evaluated the impacts of plot location error and plot size on the accuracy of AGB estimations predicted from LiDAR data in two types of tropical dry forests in Yucatán, México. We sampled woody plants of three size classes in 29 nested plots (80 m2, 400 m2 and 1000 m2) in a semi-deciduous forest (Kiuic) and 28 plots in a semi-evergreen forest (FCP) and estimated AGB using local allometric equations. We calculated several LiDAR metrics from airborne data and used a Monte Carlo simulation approach to assess the influence of plot location errors (2 to 10 m) and plot size on ABG estimations from LiDAR using regression analysis. Our results showed that the precision of AGB estimations improved as plot size increased from 80 m2 to 1000 m2 (R2 = 0.33 to 0.75 and 0.23 to 0.67 for Kiuic and FCP respectively). We also found that increasing GPS location errors resulted in higher AGB estimation errors, especially in the smallest sample plots. In contrast, the largest plots showed consistently lower estimation errors that varied little with plot location error. We conclude that larger plots are less affected by co-registration error and vegetation conditions, highlighting the importance of selecting an appropriate plot size for field forest inventories used for estimating biomass.

Article

AIRBORNE LASER SCANNER FOREST BIOMASS PLOT SIZE CO-REGISTRATION ERROR MONTE CARLO SIMULATION BIOLOGÍA Y QUÍMICA BIOLOGÍA Y QUÍMICA

Condition index in three size classes of the smooth venus clam Chionista fluctifraga from a commercial fishery in Sonora, Mexico

Índice de condición en tres clases de talla de la almeja negra Chionista fluctifragade una pesquería comercial en Sonora, México

Jorge Eduardo Chávez Villalba José Alfredo Arreola Lizárraga Jesús Ariaana Castillo Durán (2019)

Este estudio muestra el índice de condición (IC) de la almeja Chionista fluctifraga en tres diferentes grupos de talla (pequeñas < 30 mm, medianas 30- 40 mm, y grandes > 40 mm) cosechadas mensualmente durante un año de una pesquería comercial (Sonora, México). La temperatura, salinidad, oxígeno, clorofila a, material orgánico e inorgánico particulado fueron registrados mensualmente en el sitio de estudio. Se detectaron diferencias significativas del IC mayores para almejas pequeñas (26.5 ± 3.4), seguidas por las medianas (24.0 ± 3.0) y grandes (20.2 ± 3.0). Correlaciones (Pearson) altas y moderadas de temperatura e IC fueron observadas en almejas chicas y medianas. Consecuentemente,la temperatura fue la variable que más afectó el IC y esto fue detectado durante el periodo correspondiente a la reproducción y almacenamiento de nutrientes de esta especie. Con relación a estos procesos, el IC reflejó diferente valor

nutritivo para cada grupo de almejas; alto para chicas, moderado para animales medianos y bajo para individuos grandes. Esto puede servir a los productores para seleccionar almejas con alta condición y planear las cosechas.

This study shows the condition index (CI) of the clam Chionista fluctifragain three different size groups (small <30 mm, medium 30 mm -40 mm, and large > 40 mm) harvested monthly during one year in a commercial fishery (Sonora, Mexico). Temperature, salinity, oxygen, chlorophyll a, particulate organic and inorganic concentrations were recorded once-a-month at the study site. Significant differences of CI were detected; higher for small clams (26.5 ± 3.4), followed by medium (24.0 ± 3.0) and large clams (20.2 ± 3.0). High and moderate correlations (Pearson) of temperature and CI were observed in small and medium clams. Thus, temperature was the variable affecting CI the most and this was detected during the period corresponding to reproduction and nutrient storage of the species. In relation to these processes, the CI reflected a different nutritional value for each group of clams; high for small, moderate for medium animals, and low for large individuals. This may serve to producers when selecting clams with high condition and planning harvesting

Article

Almeja negra (Chionista Fluctifraga) Smooth Venus Clam (Chione fluctifraga) CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA Physiological state Veneridae Size Temperature Management Estado fisiológico Veneridae Tamaño Temperatura Manejo

Composition of Prosobranchia-Pulmonata (Mollusca: Gastropoda) in rocky intertidal zone in the Marine Priority Region 32, Guerrero, Mexico

Carmina Torreblanca Ramírez Rafael Flores Garza Pedro Flores Rodríguez Sergio García Ibáñez José Luis Rosas Acevedo (2017)

El objetivo de esta investigación fue la descripción de la taxocenosis de las subclases Prosobranchia y Pulmonata (clase Gastropoda), asociados a la zona intermareal rocosa de la Región Marina Prioritaria 32, Guerrero, México. Basada en la riqueza de especies, la composición de la comunidad a partir de la representación de las familias, se evaluó la abundancia, distribución geográfica de las especies, se estimó los estadísticos descriptivos de las tallas (en largo) de las poblaciones y la diversidad. El muestreo se llevó a cabo en 7 sitios, la unidad de muestreo fue de 1 m-2 y el área de muestreo de 10 m-2. Se identificaron 104 especies de prosobranquios y 4 de pulmonados. Las familias Columbellidae y Muricidae fueron las mejores representadas en riqueza de especies y la familia Muricidae en abundancia. Acanthais triangularis se consideró como la representativa de la zona, la especie Macrocypraea cervinetta mostró la mayor talla. Además, 23 especies presentaron amplia distribución, 27 distribución regular y 54 distribución restringida. Veintiocho especies estuvieron representadas por un único organismo, y 6 especies por 2 organismos, estas especies son consideradas raras. Las especies raras se encontraron en las estaciones cuya característica de exposición del oleaje es de bajo a medio. La riqueza de especies fue alta y corresponde a lo esperado en una zona tropical

The aim of this research was the description of the taxocoenosis of Prosobranchia and Pulmonata subclasses (Gastropoda) associated with the rocky intertidal zone of the Marine Priority Region 32, Guerrero, Mexico. Based on known species richness, we examine the composition of the community based on the representation of families, assess abundance, the geographic distribution of species, estimate descriptive statistics of size, and estimate diversity. Sampling was conducted at 7 sites, the sampling unit was 1 m-2 and the sampling area was 10 m-2. One hundred and four species of subclass Prosobranchia and 4 species of subclass Pulmonata were identified. Columbellidae and Muricidae families showed higher species richness, meanwhile family Muricidae was the most abundant. Acanthais triangularis was the most representative species of the study area, and Macrocypraea cervinetta showed the greatest size. Twenty three species were found with broad distribution, 27 taxa with frequent distribution and 54 taxa with restricted distribution. Twenty eight species were represented by a single organism and 6 species with 2 organisms, these species were considered rare and were found in sites whose characteristic wave exposure is low to medium. Species richness was high and corresponds to that expected in the tropics

Article

Gastropoda Species richness Geographic distribution Size CIENCIAS SOCIALES CIENCIAS ECONÓMICAS

Índice de condición en tres clases de talla de la almeja negra Chionista fluctifraga de una pesquería comercial en Sonora, México

Condition index in three size classes of the smooth venus clam Chionista fluctifraga from a commercial fishery in Sonora, Mexico

Jorge Eduardo Chávez Villalba JOSE ALFREDO ARREOLA LIZARRAGA Jesús Ariaana Castillo Durán (2019)

Este estudio muestra el índice de condición (IC) de la almeja Chionista fluctifraga en tres diferentes grupos de talla (pequeñas < 30 mm, medianas 30- 40 mm, y grandes > 40 mm) cosechadas mensualmente durante un año de una pesquería comercial (Sonora, México). La temperatura, salinidad, oxígeno, clorofila a, material orgánico e inorgánico particulado fueron registrados mensualmente en el sitio de estudio. Se detectaron diferencias significativas del IC; mayores para almejas pequeñas (26.5 ± 3.4), seguidas por las medianas (24.0 ± 3.0) y grandes (20.2 ± 3.0). Correlaciones (Pearson) altas y moderadas de temperatura e IC fueron observadas en almejas chicas y medianas. Consecuentemente, la temperatura fue la variable que más afectó el IC y esto fue detectado durante el periodo correspondiente a la reproducción y almacenamiento de nutrientes de esta especie. Con relación a estos procesos, el IC reflejó diferente valor nutritivo para cada grupo de almejas; alto para chicas, moderado para animales medianos y bajo para individuos grandes. Esto puede servir a los productores para seleccionar almejas con alta condición y planear las cosechas.

This study shows the condition index (CI) of the clam Chionista fluctifraga in three different size groups (small <30 mm, medium 30 mm

- 40 mm, and large > 40 mm) harvested monthly during one year in a commercial fishery (Sonora, Mexico). Temperature, salinity, oxygen, chlorophyll a, particulate organic and inorganic concentrations were recorded once-a-month at the study site. Significant differences of CI were detected; higher for small clams (26.5 ± 3.4), followed by medium (24.0 ± 3.0) and large clams (20.2 ± 3.0). High and moderate correlations (Pearson) of temperature and CI were observed in small and medium clams. Thus, temperature was the variable affecting CI the most and this was detected during the period corresponding to reproduction and nutrient storage of the species. In relation to these processes, the CI reflected a different nutritional value for each group of clams; high for small, moderate for medium animals, and low for large individuals. This may serve to producers when selecting clams with high condition and planning harvesting.

Article

Almeja Negra (Chionista Fluctifraga) Smooth Venus Clam (Chione fluctifraga) BIOLOGÍA Y QUÍMICA Estado fisiológico Veneridae Tamaño Temperatura Manejo Physiological state Size Temperature Management

Riccati parametric deformations of the Cornu spiral

Haret Codratian Rosu Stefan C. Mancas ELIZABETH FLORES GARDUÑO (2018)

"In this article, a parametric deformation of the Cornu spiral is introduced. The parameter is an integration constant which appears in the general solution of the Riccati equation and is related to the Fresnel integrals. The Argand plots of the deformed spirals are presented and a supersymmetric (Darboux) structure of the deformation is revealed through the factorization approach."

Article

Argand Plot Cornu Spiral Darboux Distortion General Solution Riccati Equation CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA FÍSICA

Electrochemical Noise Analysis of Corrosion Behavior of Stainless Steel 304 Exposed in NaCl and FeCl3 solutions

ARACELI MANDUJANO RUIZ JORGE MORALES HERNANDEZ FEDERICO CASTAÑEDA ZALDIVAR Héctor Herrera Hernández (2017)

The authors thanks to the Center of Research and Technological Development in Electrochemistry, S.C. (CIDETEQ) who supported this research with the scholarship conceded by the National Commission on Science and Technology (CONACYT). Also, thanks to the Autonomous University of the Mexican State (UAEM) for the research project conducted in CU UAEM Valle de Mexico (Laboratory of Electrochemical and Corrosion of industrial materials).

Electrical parameters such as charge of the event (q), characteristic frequency (fn) and impedance (Zn) obtained from shot-noise theory have been proposed as indicators of the initiation of pitting corrosion, and have played an important role in the construction of corrosion patterns which are a good approximation to examine the evolution of corrosion type in metals and its alloys. Therefore, in this research paper, Electrochemical Noise (EN) signals (potential and current noise data) have been collected from AISI 304 stainless steel exposed to chloride solution to evaluate the pitting corrosion behavior. The electrochemical tests were carried out at standard condition during 24 hours of exposure in two chlorine solutions (NaCl and FeCl ). Noise data analysis was mathematical treated by wavelet transform in order to identify the low frequencies that lead the calculation of q, fn and Zn to plot the corrosion behavior and this was correlated with the Energy Distribution Plots (EDP) and metallographic images. The results of all the time series evaluated reveals a concordance in scale of EDP with the initiation and the growth of pitting.

EVALUACIÓN MATEMÁTICA DE ACEROS INDUSTRIALES Y SU COMPORTAMIENTO ELECTROQUÍMICO MEDIANTE INTELIGENCIA ARTIFICIAL Folio asignado 4365/2017/CID Modalidad “D” Investigación Básica Aplicada Área de conocimiento Ingeniería y Tecnología Vigencia 01/06/2017 – 01/06/2018

Article

Electrochemical noise Pitting corrosion Wavelet Transform Energy Distribution Plot 304SS BIOLOGÍA Y QUÍMICA

Una expresión explícita para la potencia media de pruebas de no inferioridad para la comparación de proporciones

EMMANUEL ANGUIANO MONDRAGON (2013)

Tesis (Doctorado en Ciencias, especialista en Estadística).- Colegio de Postgraduados, 2013.

Las pruebas de no-inferioridad para comparar proporciones son frecuentemente empleadas en los ensayos clínicos con el objeto de verificar si hay evidencia muestral de que un tratamiento nuevo no es significativamente inferior en eficacia al tratamiento estándar, donde el tratamiento nuevo presenta algunas ventajas sobre el tratamiento estándar como por ejemplo: tener menos efectos secundarios, ser más barato o ser más fácil de aplicar. Un buen número de pruebas de no-inferioridad se han reportado en la literatura. Desafortunadamente, las comparaciones de las pruebas de no inferioridad reportadas hasta ahora son insatisfactorias pues se han realizado utilizando simulaciones o aproximaciones gruesas. Utilizando el concepto de “potencia media”, Martín-Andrés y Silva-Mato [20] desarrollaron un método nuevo para comparar las potencias de pruebas exactas de superioridad para la diferencia de proporciones. En este trabajo, este método se ha extendido para la comparación de potencias de pruebas exactas de no-inferioridad. Para ilustrar la aplicación de este método, hemos comparado dos pruebas exactas de no-inferioridad comúnmente usadas en la práctica para comparar proporciones: la prueba de Razón de Verosimilitudes (RV) y la prueba de Farrington-Manning (FM). Se obtiene como conclusión que, basados en este método, la prueba RV tiene mayor potencia media que la prueba FM. _______________ AN EXPLICIT EXPRESSION FOR THE MEAN POWER OF NON-INFERIORITY TESTS FOR THE COMPARISON OF PROPORTIONS. ABSTRACT: Noninferiority tests for comparing two proportions are frequently used in practical applications, for instance in the important field of clinical trials. The objective is to verify, based on sample data, that a new treatment with few side effects, or low cost, or easier to use, is not significantly inferior in efficacy to the standard treatment. There are several noninferiority tests for comparing two proportions reported in the literature. Unfortunately, the reported comparisons of powers of noninferiority tests are based on simulations or gross approximations. By using the concept of “mean power”, Martin-Andres and Silva-Mato [20] developed a new method to compare the powers of superiority tests for the difference of proportions. In the present work, this method is extended to the comparison of powers of noninferiority exact tests. To illustrate this new method we have compared two popular noninferiority exact tests for the difference of proportions: the Likelihood Ratio test (LR) and the Farrington-Manning test (FM). Based on the methodology developed in this work, we have obtained the conclusion that the LR test has greater mean power than the FM test.

Doctoral thesis

Pruebas de no-inferioridad Potencia Potencia media Tamaños de prueba Non-inferiority tests Power Mean power Test size Estadística Doctorado CIENCIAS SOCIALES

Phylogenetic evidence from freshwater crayfishes that cave adaptation is not an evolutionary dead-end.

David Stern CARLOS SALVADOR PEDRAZA LARA MARILU LOPEZ MEJIA Christopher Owen (2017)

"Caves are perceived as isolated, extreme habitats with a uniquely specialized biota, which long ago led to the idea that caves are “evolutionary dead-ends.” This implies that cave-adapted taxa may be doomed for extinction before they can diversify or transition to a more stable state. However, this hypothesis has not been explicitly tested in a phylogenetic framework with multiple independently evolved cave-dwelling groups".

Article

Caves Crayfish Diversification Habitat Range size Synthesis CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS CIENCIA DE LOS ORDENADORES INFORMÁTICA

Estructura poblacional de Litsea glaucescens Kunth en bosques bajo manejo de la sierra norte de Oaxaca.

VICENTE FLORENCIO VASQUEZ CORTEZ (2016)

Tesis (Maestría en Ciencias, especialista Forestal).- Colegio de Postgraduados, 2016.

Litsea glaucescens Kunth (Laurel), es una especie forestal no maderable integrada desde el año 2001 en la categoría de peligro de extinción (P) de la NOM-059. Esta especie se desarrolla en el subdosel de bosques de pino-encino de la Sierra Norte de Oaxaca y cuando se aplica la corta de regeneración a través del método de “árboles padres” y cortas intermedias, es controlada para favorecer la repoblación y crecimiento de especies del género Pinus spp. A la fecha existe escasa información con relación al efecto de las prácticas silvícolas sobre las poblaciones de laurel, por lo que el objetivo general del presente estudio fue analizar la estructura poblacional de Litsea glaucescens, en cuatro condiciones de manejo forestal prevalecientes en San Juan Evangelista, Analco, Ixtlán, Oaxaca. Para ello, se establecieron 16 unidades permanentes de muestreo (UPM) de 25 × 25 m (625 m2), cuatro en cada condición de manejo forestal (CMF): área de producción con regeneración (APR), área de producción con aclareo (APA), área de producción sin manejo (APSIF) y área de conservación con bosque maduro(ACBM). Se registró un total de 20 especies arbóreas pertenecientes a 12 familias. Con base en indicadores ecológicos como el índice de valor de importancia (IVI) y el índice de valor forestal (IVF), se determinó que las especies más importantes en las CMF fueron Pinus patula, P. pseudostrobus, Quercus laurina y L. glaucescens. Las gráficas de distribución tanto de diámetro como de altura para L. glaucesens fueron semejantes a una distribución de “J” invertida, sin embargo, la ACBM presentó tendencia a una distribución normal. El patrón de distribución y correlación espacial calculado con la función K(t) y K12(t) de Ripley, respectivamente, mostró que en todos los estadios de desarrollo de laurel este varió entre agregado y aleatorio para las cuatro CMF y la correlación fue espacialmente independiente. Se concluye que aun cuando L. glaucescens es removida durante la corta de regeneración a través del método de “árboles padres” y cortas intermedias, ésta tiene la capacidad de regenerarse por rebrotes, y alcanzar altas densidades en estado de plántula y brinzal a diferencia de condiciones con estructura de dosel cerrado (APSIF y ACBM), donde la repoblación es a través de semilla. _______________ POPULATION STRUCTURE OF Litsea glaucescens Kunth IN MANAGED FOREST AT SIERRA NORTE DE OAXACA. ABSTRACT: Litsea glaucescens Kunth (Mexican bay), is a non-timber forest species registered since 2001 in the NOM-059 with the status of risk of extinction. It is a subcanopy species in the pine-oak forests of the Sierra Norte of Oaxaca, and when the regeneration cutting through the seed tree method is applied and during thinning, this species is controlled to favor the regeneration and growth of Pinus spp. Currently there is few information regarding the effect of silvicultural practices on the Mexican bay populations. For this reason, the general objective of this study was to analyze the population structure of Litsea glaucescens, in four forest management conditions at San Juan Evangelista, Analco, Ixtlán, Oaxaca. I established 16 permanent sampling units (UPM) of 25 × 25 m (625 m2), four in each management condition (CMF): production with regeneration site (APR), production with thinning site (APA), production without cutting site (APSIF), and conservation with mature forest site (ACBM). Twenty tree species of 12 botanical families were registered. According to ecological indicators, such as the Index of Importance Value (IVI) and Index of Forest Value (IVF), the most important species in the CMF were Pinus patula, P. pseudostrobus, Quercus laurina y L. glaucescens. Diameter and height histograms of L. glaucesens were similar to an “inverted J” shape, however, the ACBM site showed a tendency to a normal distribution. The spatial distribution and correlation patterns computed through Ripley´s K(t) and K12(t), respectively, showed that all developmental stages of Mexican bay varied from clumped to random for the four CMF, and the spatial correlation was independent among developmental stages. It is concluded that even when L. glaucescens is removed during the regeneration cutting though the seed tree method and thinning, this species has the ability of sprouting, and it reaches high seedling and sapling densities, opposite of that in closed canopy conditions (APSIF and ACBM), where the regeneration is mainly by seeds.

Master thesis

Litsea glaucescens Estructura Diversidad Distribución espacial Size structure Diversity Abundance Spatial distribution Ciencias Forestales Maestría CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS CIENCIA FORESTAL PROTECCIÓN

Breed and environmental factors of sows and their repeatabilities in central Mexico

JOSE CANDELARIO SEGURA CORREA JOSE HERRERA CAMACHO ROSA ELENA PEREZ SANCHEZ ERNESTINA GUTIERREZ VAZQUEZ (2015)

Background: reproductive traits influence lifetime productivity of sows. Objective: to determine the effects of year and season of farrowing, parity number, and breed, on litter size at birth, weaning to service interval (WSI), farrowing to service interval (FSI), and to estimate their repeatabilities. Methods: data from years 1998 to 2008 from a farm in La Piedad, Michoacan, Mexico, were used. Sow breeds were Camborough 22 (PIC), Yorkshire (Y), F1 Landrace x Yorkshire (F1 LY), and ¼ Landrace x ¾ Yorkshire (LY3/4). The studied traits were total pigs born at birth (TPB, n = 45,798), number of pigs born alive (PBA, n = 45,798), WSI (n = 41,156), and FSI (n = 41,156). The statistical model for TPB and PBA included the effects of farrowing year, farrowing season, parity number, breed, and year/season interaction. The model for WSI and FSI included the above factors plus the linear and quadratic effects of lactation length. Results: the overall means for TPB, PBA, WSI, and FSI were 9.31 pigs, 8.60 pigs, 7.87 days, and 29.9 days, respectively. All effects included in the statistical models were significant (p<0.05), except season for TPB and PBA. TPB and PBA increased up to parity 4 and decreased thereafter. The LY3/4 and PIC breed groups had the highest litter size means. The shortest WSI and FSI corresponded to the fall season and the largest to the summer season. WSI and FSI decreased with parity. The Y breed had the shortest and the F1 LY sows had the highest WSI and FSI. The repeatability estimates for TPB, PBA, WSI, and FSI were 0.13, 0.12, 0.14, and 0.14, respectively. Conclusions: year, parity, breed, and lactation length affected litter size, WSI, and FSI. Repeatabilities were low, suggesting that environmental factors are more important than genetic factors for improving the reproductive traits.

Article

BIOLOGÍA Y QUÍMICA MEDICINA Y CIENCIAS DE LA SALUD Farrowing to service interval Litter size Pigs born alive Total pigs born Weaning to service interval