Global climate change affects not only temperature but also the hydrologic cycle and therefore the aridity index, with variations at the local level. A non-parametric analysis was carried out on time series data collected from temperature and precipitation records (1970 to 2011) from 38 CONAGUA (National Water Commission) weather stations located in the Mexican states of Sinaloa, Baja California Sur, Durango, Sonora, and Chihuahua. The magnitude of change trends of average, maximum, and minimum temperature and precipitation, potential evapotranspiration, and the aridity index were calculated. The data were aggregated, and the Mann-Kendall statistic calculated using the MOCLIC 1.0 program, to determine whether there was continuity in the data from each station and to define the magnitude of the statistically significant trend under the threshold α=0.05. The magnitude of the change trend was determined for significant trends using Sen’s method of slopes. Potential evapotranspiration and the aridity index were calculated by the Hargreaves and UNEP methods. The results show that the climate variables displayed positive and negative trends; mainly temperature, with a range of -0.13 to 0.16ºC·yr^-1, which is above world averages. The values obtained for RMSE, bias, the Pearson correlation coefficient (r) and the coefficient of determination (R²) do not show significant differences between the control values and the calculated values. It was concluded that aggregating significant trends can provide information on the direction of local climate change in this environment in northern Mexico, and its important consequences and repercussions, as well as impacts on social and environmental systems.

This study investigates the historical variability in annual average precipitation in the northwest region of Mexico, aiming to evaluate the cumulative impact of precipitation on soil degradation and associated risks posed by rainfall. Despite being known as “The Agricultural Heart of Mexico”, the region’s soil has experienced significant damage to its granulometric structure due to unpredictable rainfall patterns attributed to climate change. Sixteen historical series of average annual rainfall were analyzed as stationary stochastic processes for spectral analysis. The results revealed exponential decay curves in each radial spectrum, indicating a linear relationship between frequency and amplitude. These curves identified initial impulses correlated with moments of severity for structural damages caused by rainfall-induced degradation. The degradation process, exacerbated by water stress, accelerates, as evidenced by maps illustrating approximately 75% soil damage. In the context of climate change and the uncertainty surrounding soil responses to extreme meteorological events, understanding this phenomenon becomes crucial. Recognizing the dynamic nature of soil responses to environmental stressors is essential for effective soil management. Emphasizing the need to employ numerical processes tailored to new environmental considerations related to observed soil damages is crucial for sustainable soil management practices in any region.

Background. For its flesh and flavor, the Pacific oyster Crassostrea gigas is cultivated worldwide, but as filter feeders, this bivalve bioaccumulates heavy metals from different pollution sources, rendering them unsafe for human consumption. Goals. We carried out this study to assess the heavy metal concentrations in cultivated oysters from a farm located on the southeastern coast of the Gulf of California during 2011. Methods. Oyster samples were analyzed monthly (March- December 2011) for cooper (Cu), cadmium (Cd), chromium (Cr), nickel (Ni), lead (Pb), zinc (Zn), arsenic (As), and mercury (Hg). Results. The mean values (μg g-1, dry weight) for each metal were Cu = 51.42 ± 25.92, Cr = 24.97 ± 32.38, Cd = 13.84 ± 4.22, Ni = 10.26 ± 12.18, Pb = 2.18 ± 1.28, As = 0.37 ± 0.08, Zn = 267.42 ± 92.29, and Hg = 0.02 ± 0.01. Conclusions. The results suggest that metal burdens could be influenced by anthropogenic activities such as agriculture and aquaculture surrounding the culture zone. Cu, Cr, Cd, and Pb levels (μg g-1, fresh weight) were above the maximum permissible values and thus pose a threat to human health. Metal concentrations must be monitored periodically. Background. For its flesh and flavor, the Pacific oyster Crassostrea gigas is cultivated worldwide, but as filter feeders, this bivalve bioaccumulates heavy metals from different pollution sources, rendering them unsafe for human consumption. Goals. We carried out this study to assess the heavy metal concentrations in cultivated oysters from a farm located on the southeastern coast of the Gulf of California during 2011. Methods. Oyster samples were analyzed monthly (March- December 2011) for cooper (Cu), cadmium (Cd), chromium (Cr), nickel (Ni), lead (Pb), zinc (Zn), arsenic (As), and mercury (Hg). Results. The mean values (μg g-1, dry weight) for each metal were Cu = 51.42 ± 25.92, Cr = 24.97 ± 32.38, Cd = 13.84 ± 4.22, Ni = 10.26 ± 12.18, Pb = 2.18 ± 1.28, As = 0.37 ± 0.08, Zn = 267.42 ± 92.29, and Hg = 0.02 ± 0.01. Conclusions. The results suggest that metal burdens could be influenced by anthropogenic activities such as agriculture and aquaculture surrounding the culture zone. Cu, Cr, Cd, and Pb levels (μg g-1, fresh weight) were above the maximum permissible values and thus pose a threat to human health. Metal concentrations must be monitored periodically.

This paper has as its object of study the coastal and marine areas of Mexico; specifically, it focuses on the analysis of existing barriers for the implementation of actions tending to the adaptation to climate change of these fragile and dynamic regions of the national territory. The study makes a general review of the main meetings, agreements and international entities related to the global climate that have served as the basis for the XXI Conference of the Parties, from which emanated the "Paris Agreement". After analyzing some implications of the aforementioned agreement and presenting evidence of the current situation, the main legal and normative instruments of the national marine and coastal areas are reviewed; the main risks in these areas of the national territory associated with climate change are evaluated; the main existing adaptation measures are analyzed; and, the most important socioeconomic and political barriers that exist for their correct implementation are established. Finally, some lines of action are proposed to improve the current vulnerability of the coastal areas and increase their resilience.

In order to generate proposals to strengthen environmental governance, this article studies social participation in the management of the Flora and Fauna Protection Area of the Gulf of California Islands. Based on direct observation and semi-structured interviews, the perception of public officials, specialists and users with respect to this process was analyzed in the framework of a qualitative inquiry; generating as results twenty-nine interviews with stakeholders. The main limitation for this study is the open refusal of users of this protected area to be interviewed due to the mistrust they have of public entities. The collection of experiences and perceptions of direct actors in the management of the mentioned area gives originality to this article. It is concluded that Comisión Nacional de Áreas Naturales Protegidas lacks credibility before the social organization as a result of a vertical instrumentation of its strategies without effectively considering the participation of the affected communities.