Socio-spatial segregation of socio-environmental assets of public green spaces in the city of Durango, Mexico

Carlos Alejandro Custodio González Tania Ortiz Patricia Catalina Medina Pérez (2024, [Artículo, Artículo])

The current development model's accumulation logic has resulted in the emergence and consolidation of social processes like segregation, leading to differentiated access and availability of urban goods and services among social groups based on socioeconomic, ethnic, or societal standing. The current development model's accumulation logic has resulted in the emergence and consolidation of social processes like segregation, leading to differentiated access and availability of urban goods and services among social groups based on socioeconomic, ethnic, or societal standing. This disparity impacts employment levels, educational performance, urban decay, and environmental degradation. In this context, the article aims to examine the socio-spatial segregation in the access to socio-environmental amenities provided by public green spaces (EVP) in a medium-sized city, specifically Durango, Mexico. The analysis utilizes spatial analysis and statistical methods that involve five variables associated with EVPs: surface area, percentage, number, density, and the socioeconomic level of the population. A spatial pattern of segregation was identified through these variables, resulting in four clusters that impact how the city of Durango is inhabited, produced, reproduced, lived, and constructed.

sociospatial exclusion public space spatial autocorrelation spatial patterns spatial justice exclusión socioespacial espacio público autocorrelación espacial patrones espaciales justicia espacial CIENCIAS SOCIALES CIENCIAS SOCIALES

Using homosoils for quantitative extrapolation of soil mapping models

Andree Nenkam Alexandre Wadoux Budiman Minasny Alex McBratney Pierre C. Sibiry Traore Gatien Falconnier Anthony Whitbread (2022, [Artículo])

Cubist Digital Soil Mapping Model-Based Validation Soil Spatial Variation Soil-Forming Factors CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA LAND USE ORGANIC CARBON SOIL SURVEYS SPATIAL VARIATIONS

GENERATION OF LG VECTOR MODES WITH ULTRAHIGH STABILITY BASED ON COMPLEX AMPLITUDE MODULATION IN AN ON-AXIS CONFIGURATION

Gloria Elizabth Rodríguez García (2023, [Tesis de maestría])

"This thesis presents a novel technique for generating vector beams using complex amplitude modulation (CAM) in an on-axis configuration. The holograms used to generate the beams were created using the Mathlab software and displayed on a reflective spatial light modulator (SLM). The main goal of this research was to address both the purity and stability of the beams during generation and propagation, introducing a quantitative approach to assess their stability. As a proof-of-concept, Laguerre-Gaussian vector beams have been generated and characterized using Stokes polarimetry with the proposed experimental set up."

Structured light Laguerre-Gauss vector beams Stokes polarimetry Beam generation Spatial light modulators CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA OPTICA FÍSICA OPTICA FÍSICA

Geospatial analysis of the distribution of empty spaces located in Nuevo Laredo, Tamaulipas

Claudio Curzio HECTOR DE LA TORRE GUTIERREZ (2021, [Artículo, Artículo])

Reflect about urban empty spaces means looking around all these lots that are distributed in different geographical points of the cities and are characterized because they are still waiting to be built, therefore, they are vacant, and also these spaces are empty in the sense of not provide any function. In this sense, the objective of this article is to present a methodological proposal specially designed to study this type of urban elements from the particular point of view of urban geography and spatial analysis. Specifically, through a series of surveys, both digital and physical, the various urban voids located in the city of Nuevo Laredo were recorded, thereby creating a database that included a total of 3,836 case studies. In this way, using different types of statistical techniques and spatial models, it was possible to obtain and interpret the results, managing to identify exactly what were the main patterns and characteristics of said geographic distribution.

empty spaces urban vacant lots geo-spatial analysis urban geography border in Nuevo Laredo Vacíos urbanos lotes baldíos análisis geo-espacial geografía urbana frontera en Nuevo Laredo Geografía urbana economía urbana morfología urbana CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Variación espacio-temporal del ensamblaje de peces criptobentónicos y conspicuos en dos áreas naturales protegidas, Bahía de los Ángeles y Huatulco

Spatial and temporal variation of the assemblage of cryptobenthic and conspicuous reef fish in two protected natural areas, Bahía delos Ángeles and Huatulco

Rodrigo Daniel Chiriboga Ortega (2023, [Tesis de maestría])

Los peces arrecifales desempeñan roles ecológicos muy importantes manteniendo la salud de los arrecifes siendo limpiadores, recicladores de materia orgánica y además fuente de alimento entre eslabones de la cadena trófica. El presente trabajo busca describir el ensamblaje de peces arrecifales crípticos y conspicuos, y evaluar los patrones espaciales y temporales del ensamblaje de peces arrecifales en Bahía de Los Ángeles, Baja California (BLA) y el Parque Nacional Huatulco (PNH), Oaxaca. Utilizamos dos métodos de muestreo censos visuales y estaciones cerradas. Para evaluar a los peces conspicuos, se realizaron censos visuales empleando transectos de banda de 20x4 m. Para cuantificar la biodiversidad de peces crípticos, se realizaron estaciones cerradas (0.4 m2 ) en donde se utilizó aceite de clavo como anestésico para recolectar los peces arrecifales criptobentónicos (PACr). Las dos metodologías se realizaron en dos gradientes de profundidad (somero; < 5 m y profundo; > 5 m) y en dos estaciones (cálida y fría). Se realizaron curvas de acumulación de especies y un análisis del número efectivo de especies para describir la riqueza y diversidad de cada zona de estudio. Finalmente, para determinar patrones espacio temporales se realizaron análisis nMDS, PERMANOVAS y SIMPER. La riqueza total fue de 43 especies para BLA y 62 para el PNH representando el 80% y 79% del promedio de los estimadores no paramétricos respectivamente. Se aumentó el número de especies registradas a 94 para BLA y 209 para el PNH utilizando las estaciones cerradas. Se observaron diferencias significativas entre estaciones y profundidad en el ensamblaje de PACs de BLA, pero no para los PACr. En el PNH se observaron diferencias significativas para la riqueza y abundancia de los PACr y variación temporal de la biomasa de los PACs. En conclusión se demostró que el uso de métodos de muestreo complementarios mejora la calidad de los inventarios de especies y permite detectar variaciones espacio temporales en la estructura de la comunidad íctica.

Reef fishes perform important ecological roles in maintaining reef health by cleaning and recycling organic material, and by providing a source of food between trophic linkages. The thesis describes cryptic and conspicuous reef fish assemblages and estimates their spatial and temporal patterns of in two sites, Bahía de Los Ángeles (BLA) in the state of Baja California and Huatulco National Park (PNH), in the state of Oaxaca. We used two sampling methods: visual census using SCUBA (band transects of 4x20m) for conspicuous reef fish (PAC) and enclosed stations (0.4 m2) using clove oil to anesthetize and collect the cryptobenthic reef fish (PACr). Sampling was conducted at two depth strata (shallow; < 5 m and deep; > 5m) and during two seasons (warm and cold). We used species accumulation curves and analysis of effective number of species to describe the richness and diversity of reef fish. Finally, nMDS, PERMANOVAS and SIMPER were performed to determine spatial and temporal patterns. The total species richness was 43 species for BLA and 62 species for the PNH, representing 80% and 79%, respectively, of the average of the non-parametric estimators. The number of species increased to 94 for BLA and 209 for PNH using enclosed stations. Significant differences between seasons and depth strata were found for the PACs assemblage at the BLA site, but not for the PACr assemblage. At the PNH site, significant differences were found for the richness and abundance of the PACr assemblage for depth as well as for the seasonal variation of the biomass of the PACs assemblage. In conclusion we demonstrated that the use of complementary sampling methods improves the quality of species inventories and allows for the detection of both spatial and temporal variations in the structure of the reef fish community.

diversidad, peces arrecifales, criptobentónico, biomasa, espacio-temporal biodiversity, reef fishes, cryptobenthic, biomass, spatial-temporal CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE DINÁMICA DE LAS POBLACIONES DINÁMICA DE LAS POBLACIONES

Spatial Effects of Urban Transport on Air Pollution in Metropolitan Municipalities of Mexico

GERZAIN AVILES POLANCO Marco Antonio Almendárez Hernández Luis Felipe Beltrán Morales Alfredo Ortega Rubio (2022, [Artículo])

"The objective of this work was to estimate the local effects and spatial spillover effects of the number of vehicles, use of urban public transport, and population density on nitrogen oxide emissions for 405 metropolitan municipalities in Mexico in 2016. To this end, a Spatial Durbin Model was estimated. We found positive direct effects of the number of vehicles and population density and negative direct effects of the use of urban public transport. The number of vehicles in circulation had negative spillover effects on the nitrogen oxide emissions of neighboring municipalities. These results indicate that the design of public policy programs aimed at reducing air pollution in Mexico should be based on coordination across metropolitan municipalities."

private car transportation, air pollution, nitrogen oxide emissions, spatial spillover effects, metropolitan municipalities CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO METEOROLOGÍA CONTAMINACIÓN ATMOSFÉRICA CONTAMINACIÓN ATMOSFÉRICA

Contrasting spatial patterns in active-fire and fire-suppressed mediterranean climate old-growth mixed conifer forests

Danny L. Fry  (2014, [Artículo])

In Mediterranean environments in western North America, historic fire regimes in frequent-fire conifer forests are highly variable both temporally and spatially. This complexity influenced forest structure and spatial patterns, but some of this diversity has been lost due to anthropogenic disruption of ecosystem processes, including fire. Information from reference forest sites can help management efforts to restore forests conditions that may be more resilient to future changes in disturbance regimes and climate. In this study, we characterize tree spatial patterns using four-ha stem maps from four old-growth, Jeffrey pine-mixed conifer forests, two with active-fire regimes in northwestern Mexico and two that experienced fire exclusion in the southern Sierra Nevada. Most of the trees were in patches, averaging six to 11 trees per patch at 0.007 to 0.014 ha-1, and occupied 27-46% of the study areas. Average canopy gap sizes (0.04 ha) covering 11-20% of the area were not significantly different among sites. The putative main effects of fire exclusion were higher densities of single trees in smaller size classes, larger proportion of trees (≥56%) in large patches (≥10 trees), and decreases in spatial complexity. While a homogenization of forest structure has been a typical result from fire exclusion, some similarities in patch, single tree, and gap attributes were maintained at these sites. These within-stand descriptions provide spatially relevant benchmarks from which to manage for structural heterogeneity in frequent-fire forest types.

article, climate, controlled study, ecosystem fire history, forest structure, geographic distribution, geographic mapping, land use, mathematical computing, mathematical model, Mexico, spatial analysis, taiga, United States, comparative study, conife CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA