Andrea González-Fernández’s research while affiliated with National Autonomous University of Mexico and other places

Since the 1970s, remote sensing has been used to monitor the environment, address national security concerns, and manage Earth resources within a market framework. However, environmental organizations can also utilize remote sensing data infrastructure to support oppositional narratives, legal processes, and direct action. We present a framework for the socio-technical practice of remote sensing in alliance with those communities and organizations that are struggling for environmental justice on the global commodity frontiers. Positioned at the intersection of critical geography and political ecology, we examine the ways that critical remote sensing has been adopted in five major types of environmental conflict: struggles opposing fossil fuel exploitation, timber extraction, intensive food production, water management practices, and the effects of mining. We present a baseline inventory of remote sensing resources that are useful to the five conflict types and are freely accessible online. A global perspective on the planetary environmental crisis is essential, and we suggest that remote sensing practitioners can, through workshops or online tutorials, help environmental justice organizations towards independent use of remote sensing data. The local communities should then determine whether remote sensing products can contribute to their struggles.

La quema de pastizales en México provoca contaminación del aire, pérdida de biodiversidad y erosión del suelo, por ello es crucial abordar este problema integralmente con énfasis en la educación ambiental. Los programas dirigidos a comunidades, agricultores y jóvenes pueden aumentar la conciencia sobre los impactos negativos y fomentar comportamientos responsables. Asimismo, la colaboración entre autoridades y sociedad es esencial para mitigar estos impactos y garantizar un futuro sostenible. Toluca es un ejemplo de ciudad que debe implementar medidas para reducir las quemas de pastizales y proteger el medio ambiente.

Little is known about fire as an agent of direct animal mortality, and specifically, there is controversy regarding the effects of fire on reptiles. In the Sierra Morelos natural protected area in Mexico, both unplanned (e.g., man-made illegal and accidental burns) and prescribed burns occur during the dry season. In this study, we assessed direct fire-induced reptile mortality in the Sierra Morelos natural protected area by comparing live and dead individuals. Of the 14 reptile species reported in the area, seven were found dead due to fire. One-third of the individuals found in 2021 (34% of 169 ind.) and 2022 (33% of 33 ind.) were killed by fire. The mean density of detected dead individuals was 1.60 ± 2.99 individuals/ha in 2021 and 0.31 ± 0.27 individuals/ha in 2022. Mortality densities were similar in areas subjected to prescribed burns and in areas affected by unplanned burns (W= 37.5, p = 0.4383). Since our survey likely underestimated the actual mortality caused by fire, our findings show the important direct impact of fire on the reptile community of the Sierra Morelos natural protected area and support the notion that anthropogenic fire can represent a serious risk for reptiles in fragile ecosystems.

Anthropogenic land use and climate change are the greatest threats to biodiversity, especially for many globally endangered reptile species. Earth snakes (Conopsis spp.) are a poorly studied group endemic to Mexico. They have limited dispersal abilities and specialized niches, making them particularly vulnerable to anthropogenic threats. Species distribution models (SDMs) were used to assess how future climate and land-cover change scenarios might influence the distribution and habitat connectivity of three earth snakes: Conopsis biserialis (Taylor and Smith), C. lineata (Kennicott), and C. nasus (Günther). Two climate models, CNRM-CM5 (CN) and MPI-ESM-LR (MP) (Representative Concentration Pathway 85), were explored with ENMeval Maxent modelling. Important SDM environmental variables and environmental niche overlap between species were also examined. We found that C. biserialis and C. lineata were restricted by maximum temperatures whereas C. nasus was restricted by minimum ones and was more tolerant to arid vegetation. C. biserialis and C. lineata were primarily distributed in the valleys and mountains of the highlands of the TMBV, while C. nasus was mainly distributed in the Altiplano Sur (Zacatecano-Potosino). C. lineata had the smallest potential distribution and suffered the greatest contraction in the future whereas C. nasus was the least affected species in future scenarios. The Sierra de las Cruces and the Sierra Chichinautzin were identified as very important areas for connectivity. Our results suggest that C. lineata may be the most vulnerable of the three species to anthropogenic and climate changes whereas C. nasus seems to be less affected by global warming than the other species.

Anthropogenic changes, such as land use and climate change, are the greatest threats to biodiversity, especially for reptiles, the second most endangered vertebrate class worldwide. Species distribution modelling was applied to assess how expected scenarios of future climate and land cover change might influence the geographic distribution and habitat connectivity of three Conopsis earthsnakes endemic to Mexico: Conopsis biserialis (Taylor and Smith, 1942), Conopsis lineata (Kennicott, 1859), and Conopsis nasus (Günther, 1858). In order to do this, two climate models were used, CNRM-CM5 (CN) and MPI-ESM-LR (MP), with the Representative Concentration Pathways of RCP 85 and the Maxent modelling method in ENMeval. The most important environmental variables affecting the distribution of the target species, as well as the environmental niche overlap between them, were also determined. C. biserialis, C. lineata , and C. nasus were found to be restricted by maximum and minimum temperatures as they are adapted to high elevations and temperate semi-cold climates; therefore, climate was a main determining factor for species distribution. As expected, all Conopsis species were predicted to face a reduction in their potential distribution with C. lineata possibly losing approximately 48.5% and C. biserialis losing 28.7%. However, the models were inconsistent in determining which species would suffer the biggest reduction in distribution in the future. Likewise, a reduction in connectivity was found for the three species of Conopsis , while the Sierra de las Cruces and Corredor Biológico Chichinautzin were determined as very important areas in terms of connectivity. Unfortunately, great losses of Abies and Pinus forests occurred in these areas between 2011 and 2014, along with an increase in the agricultural activity that compromises the populations of these species when intensively managed. Most of the potential distribution of these species are found in close proximity to agriculture and outside of protected areas, which is why it is extremely important to create protected areas for reptile species that live in these parts of central Mexico.

Anthropogenic changes, such as land use and climate change, are the greatest threats to biodiversity, especially for reptiles, the second most endangered vertebrate class worldwide. Species distribution modelling was applied to assess how expected scenarios of future climate and land cover change might influence the geographic distribution and habitat connectivity of three Conopsis earthsnakes endemic to Mexico: Conopsis biserialis (Taylor and Smith, 1942), Conopsis lineata (Kennicott, 1859), and Conopsis nasus (Günther, 1858). In order to do this, two climate models were used, CNRM-CM5 (CN) and MPI-ESM-LR (MP), with the Representative Concentration Pathways of RCP 85 and the Maxent modelling method in ENMeval. The most important environmental variables affecting the distribution of the target species, as well as the environmental niche overlap between them, were also determined. C. biserialis, C. lineata, and C. nasus were found to be restricted by maximum and minimum temperatures as they are adapted to high elevations and temperate semi-cold climates; therefore, climate was a main determining factor for species distribution. As expected, all Conopsis species were predicted to face a reduction in their potential distribution with C. lineata possibly losing approximately 48.5% and C. biserialis losing 28.7%. However, the models were inconsistent in determining which species would suffer the biggest reduction in distribution in the future. Likewise, a reduction in connectivity was found for the three species of Conopsis , while the Sierra de las Cruces and Corredor Biológico Chichinautzin were determined as very important areas in terms of connectivity. Unfortunately, great losses of Abies and Pinus forests occurred in these areas between 2011 and 2014, along with an increase in the agricultural activity that compromises the populations of these species when intensively managed. Most of the potential distribution of these species are found in close proximity to agriculture and outside of protected areas, which is why it is extremely important to create protected areas for reptile species that live in these parts of central Mexico.

Guerrero is one of the most diverse states of Mexico, containing a large number of endemic and endangered amphibian species. However, it is one of the less protected and studied states of the country. Here, we determined the potential distribution of all amphibian species in a risk category present in Guerrero and defined priority areas for amphibian conservation in the state. We modelled the potential distribution of 32 species using the maximum entropy modelling algorithm. These models were used to define priority areas through systematic conservation planning tools. The most important variables explaining species’ potential distribution were measures of climate variability, particularly temperature seasonality. The priority areas for amphibian conservation identified covered a total area of 12,212.72 km² and contained an important proportion (almost a third) of the cloud mountain forests of the state. The most important planning units for meeting species targets and the most important planning units in terms of biodiversity overlapped in approximately the same planning units, located in the biogeographic regions of the Sierra Madre del Sur and the Pacific Coast. Finally, from the total priority areas identified, only 0.31% (38.17 km²) is currently protected within the existing natural protected areas in Guerrero. Thus, we consider that it is essential to protect additional natural areas in the state. Areas Voluntarily Destined for Conservation (ADVC) may be a good option; however, action must be taken to ensure the legitimacy of the processes by the local people and to avoid privileging only certain members of the community.

In 2013, the protection status of the Nevado de Toluca Volcano was changed from National Park to a less restrictive category. Much controversy has arisen surrounding this decision as the new category allows forest harvesting practices in most of the natural protected area. We assessed the forest cover loss in the Nevado de Toluca protected area and a 20 km buffer zone around it, before and after the change in protection status, and we established a map of forest types in view of assessing biodiversity vulnerability to the protection change in the forest harvesting areas. The forest type classification was carried out applying a Random Forest algorithm to Sentinel-2 imagery. The forest cover loss was assessed using the Landsat-based Global Forest Watch product during the period 2001-2019. Forest cover loss increased after the change of the Nevado de Toluca protection status; 39.7 hec-tares/year (± 16.7 ha/year) between 2001 and 2013 versus 106.0 hectares/year (± 40.2 ha/ year) between 2014 and 2019. Clear-cut deforestation occurred in 49.6 hectares during year 2018. According to our forest map, 7171 ha (54.8%) of the Abies religiosa forest and 6511 ha (32.5%) of the pine forests of the Nevado de Toluca protected area are inside the forest harvesting zonation. Also, forest cover loss around the natural protected area has increased, especially in 2018, indicating that allowing forest harvesting practices in the natural protected area has not reduced the pressure in the surrounding forests either. We ponder the consequences of the category change and give some suggestions for the future of the forests in the Nevado de Toluca protected area.

Habitat loss and fragmentation are among the greatest threats to biodiversity since unsuitable habitat can be a significant barrier to gene flow, disrupting the connectivity of populations. In this scenario, landscape genetic approaches have been applied as invaluable tools to demonstrate how contemporary habitat alterations affect gene flow. In this study, we used nine microsatellite genotypes to determine the landscape features driving genetic diversity, structure, and functional connectivity among eleven sampling sites of a micro‐endemic, and critically endangered salamander ( Pseudoeurycea robertsi ) in the Nevado de Toluca Volcano. We also modelled the ecological niche of P . robertsi to assess the most important habitat features associated with its probability of presence and analyzed the corridor network to identify important core areas and corridors to keep the network connected, as well as points where the network connection is lost or tightened. Moreover, we performed a redundancy analysis to assess the effect of genetic distance and habitat resistances on gene flow. We found the highest levels of genetic diversity and connectivity at the northwestern part of the Volcano. Meson Viejo sampling site was of especial importance to overall network connectivity. We found low levels of migration rates and low levels of genetic structure. The most important habitat feature associated with probability of presence of Pseudoeurycea robertsi was the Abies forest, and two models were significant under the RDA analysis: Abies forest and Abies forest+Grasslands. We recommend prioritizing the areas of the northwestern and central parts of the volcano in conservation programs. Abstract in Spanish is available with online material.