Analysis of Near-Surface Temperature Lapse Rates in Mountain Ecosystems of Northern Mexico Using Landsat-8 Satellite Images and ECOSTRESS

Mountain ecosystems provide environmental goods, which can be threatened by climate change. Near-Surface Temperature Lapse Rate (NSTLR) is an essential factor used for thermal and hydrological analysis in mountain ecosystems. The aims of the present study were to estimate NSTLR and to identify its relationship with aspect, Local solar zenith angle (LSZA) and Evaporative Stress Index (ESI) for two seasons of the year in a mountain ecosystem at the North of Mexico. Normalized Land Surface Temperature (NLST) was estimated using environmental and topographical variables. LSZA was calculated from slope to consider the effect of solar position. NSTLR was estimated through simple linear models. Observed NSTLR was 9.4 °C km−1 for the winter and 14.3 °C km−1 for the summer. Our results showed variation in NSTLR by season. In addition, aspect, LSZA and ESI also influenced NSTLR regulation. In addition, Northwest and West aspects exhibited the highest NSTLR. LSZA angles closest to 90° were related with a decrease in NSTLR for both seasons. Finally, ESI values associated with less evaporative stress were related to lower NSTLR. These results suggest potential of Landsat-8 LST and ECOSTRESS ESI to capture interactions of temperature, topography, and water stress in complex ecosystems.

Human and wildlife use of mountain glacier habitat in western North America

The global recession of glaciers and perennial snowfields is reshaping mountain ecosystems. However, beyond physical changes to the landscape and altered downstream hydrology, the implications of glacier decline are poorly known. Before predictions can be made about how climate change may affect wildlife in glacier-associated ecosystems, a more thorough accounting of the role that glaciers play in species' life histories is needed. In this study, we deployed an elevational transect of wildlife cameras along the western margin of the Paradise Glacier, a rapidly receding mountain glacier on the south side of Mount Rainier, WA, USA. From June to September 2021, we detected at least 16 vertebrate species (seven birds, nine mammals) using glacier-associated habitats. While humans, and primarily skiers, were the most common species detected, we recorded 99 observations of wildlife (birds and mammals). These included three species of conservation concern in Washington: wolverine (Gulo gulo), Cascade red fox (Vulpes vulpes cascadensis), and White-tailed ptarmigan (Lagopus leucura). Collectively, our results reveal a rich diversity of wildlife using a single mountain glacier and adjacent habitat in the Pacific Northwest, emphasizing a largely overlooked risk of climate change to mountain biodiversity. We highlight the global need for similar studies to better understand the true scale of biodiversity that will be impacted by glacier recession in mountain ecosystems.

Adapting to Receding Glaciers in the Tropical Andes

Integrated approaches are needed to understand and respond to changes in tropical mountain ecosystems and communities brought about by receding glaciers and changes in land use.

Moss Biomonitoring of Transboundary Pollutants in Japan’s Mountains

Long-range transported atmospheric pollutants (or transboundary pollutants) include trace metals with isotope ratios and compositions that vary from those of domestic pollutants, which threaten mountain ecosystems. These differences can be applied as indices (trace metal indices) to evaluate the influence of transboundary pollutants on mountain ecosystems. Mosses play important ecological functions in mountains and are sensitive to atmospheric deposition. Therefore, using these indices for moss biomonitoring can provide a more accurate indication of ecosystem health. However, few studies have examined which indices are appropriate for moss biomonitoring. In this study, the effectiveness of moss biomonitoring using trace metal indices was examined for evaluating transboundary pollutants in mountainous areas in Japan. Transboundary pollutants in these areas originate from mainland Asia and are characterized by high lead isotope ratios, lead to zinc (Pb/Zn) ratios, and arsenic to vanadium (As/V) ratios. Given that the abundance of transboundary pollutants decreases with distance from mainland Asia, moss isotope indices are also expected to vary with distance. Based on observations, Pb isotope ratios were found to decrease with distance from mainland Asia; in contrast, Pb/Zn and As/V ratios did not display any notable relationship with distance. These results are likely attributed to biological and environmental factors that affect trace metal contents in moss. Thus, moss Pb isotope ratios are useful indicators of transboundary pollutants in Japan’s mountains, offering an important tool for comparable moss biomonitoring studies in East Asia.