No abstract

Studies have shown that environmental variables significantly affect variation in stock abundance of marine populations. The northern Gulf of California (NGC) is a highly productive region of interest due to its fish resources and diversity. Conservation of the marine species inhabiting the region is of public interest. Our study analysed the influence of physical environmental factors on several commercial marine species, using catch per unit effort (CPUE) as a proxy for abundance. Generalized additive models were used to test the significance of selected environmental variables on stock abundance. Deseasonalized cross-correlation analysis was used to examine time-lagged correlations between CPUE and abiotic variables to identify response timings. The results suggest that for most commercial species the sea surface temperature and the long-term climate Pacific Decadal Oscillation index are the predominant predictors for species abundance, followed by the Colorado River discharge. The Multivariate ENSO Index and the Pacific-North American pattern indices also showed specific effects on certain species. The NGC is a highly dynamic region, where species respond to environmental changes according to the characteristics of their life histories.

Coastal zone (CZ) and adjacent land areas supports more than 50% of human population and eight of the top ten largest cities in the world. They are exposed to natural hazards and climate change induced stresses, which have led to focus as a relevant issue, the assessment of its vulnerability in many regions of the planet. Assessment and monitoring of vulnerability models in CZ should be able to influence the environmental policies, and guiding decision makers to provide the main elements for the sustainability of any coastal city. The case of study La Paz (CS) is the capital city of the biggest coastal extension state of Mexico. CS was regionalized based on biotic, natural landscape and socio-economic factors within geographic information systems, obtaining 74 environmental units (EnvU). Assessment on each EnvU with a coastal vulnerability model, used physical, environmental and socio-economic indicators and integrated indices, considering three main elements: a fixed component defined by Coastal Vulnerability Index (CVI) = Pressure Index (PI) + Fragility Index (FI). Nearly 38% of EnvU and over 60% of CS showed high and very high FI, including capital city. Only 7% of EnvU and 14% of CS presented high and very high PI. Nearly a third of EnvU had high and very high CVI, mainly on La Paz and southwest of CS without actual human pressure, but lower slopes and high-energy streams. Results allow focusing efforts on environmental policy instruments to implement adaptation measures to sustainability of the CS.

El objetivo del trabajo es evaluar el índice de aptitud de los municipios de Baja California Sur para la instalación de concentradores fotovoltaicos. La metodología propone un modelo de aptitud que incorpora seis indicadores socioambientales explícitos en términos espaciales con asignación de su contribución diferenciada o pesos por medio de análisis multicriterio. Los resultados muestran que la irradiación horizontal anual promedio en Baja California Sur es de 6.19 kW h/m2/día en el periodo 1998-2014. De la superficie total en el estado, 5.25% es viable para la instalación de concentradores fotovoltaicos. Comondú, Mulegé y La Paz presentaron los mayores valores de aptitud. Los indicadores predominantes del modelo son la red carretera, la red eléctrica y las zonas con pendientes de ˂4°. El estudio se limitó a analizar la influencia de los indicadores socioambientales en la ubicación de sistemas de concentradores fotovoltaicos. La metodología podría replicarse en otras regiones para facilitar la toma de decisiones. Los resultados sugieren que los tres municipios de Baja California Sur mencionados son los más favorables en términos socioambientales para la instalación de dichos concentradores.

The present study analyzes the vulnerability assessment as a tool and reference for a sustainable managing of the Natural Protected Area (NPA) San Jose del Cabo Estuary Mexico (ESJC). ESJC is a coastal oasis of fresh water located close to the Gulf of California mouth, and it is an important refuge for migratory birds and endemic species that inhabit the estuary. ESJC has been threatened by the rapid urbanization and tourist development in Los Cabos, which created negative effects such as land changes, sewage discharges and invasive species, affecting largely the quality of the estuary. In this context the main purpose of the study was to evaluate the vulnerability of every micro region of ESJC in order to propose management strategies of the NPA. We made a characterization and regionalization of ESJC. We propose an index (VI) based on indicators to represent the vulnerability, as well as the natural and socio-ecological pressures affecting the refuge. The VI was shaped adding fragility index (FI) and pressure index (PI). The FI and PI were created from the indicators that were normalized to dimensionless quantities ranging from 0 to 1. In result, the indexes infer a high vulnerability of the lagoon and the upstream area with natural vegetation: The FI shows the frailty due to runoffs, sediments, natural vegetation, endemic species and exposed population; the PI represents high values of pressure from tourism development, demography, runoff from floods, and the agricultural and urban activities. The integrated vulnerability evaluation from biophysical and socioeconomic aspects for a protected area allows an establishment of a management proposal strategy for sustainability of the ESJC.