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The aim of this study was to estimate the possible impact of future climate changes on the potential distribution of T. diversifolia in Mexico. Distribution niches were modelled with MaxEnt for the 1951-2000, 2041-2060 and 2061-2080 climatologies, considering 20 bioclimatic and two topographical variables. For future climates, a HadGEM2-ES general circulation model (GCM) was considered, with two representative concentration pathways of greenhouse gases (RCP4.5 and RCP8.5). This information was obtained from the Global Climate Data Website WorldClim and processed with the Idrisi Selva system as raster images with 2.5 arc min resolution. The environmental variables that contributed the most to explain the geographical distribution of T. diversifolia were the May-October mean accumulated precipitation (pa5-10) and the mean maximum temperature of the warmest month (MMAX). The 10th percentile training presence logistic threshold reported a predicted suitable area (for the reference climatology) accounting for 30.71% of the extent of Mexico. Niche modeling under climate change scenarios reported expansion as well as retraction areas for environmental suitability; however, after computing them, suitable areas are expected to present a small increment with respect to the climate reference period, 1950-2000: 31.62%, 31.83%, 32.45% and 32.45% of Mexican territory in scenarios for 2041-2060 in RCP 8.5, 2041-2060 in RCP 4.5, 2061-2080 in RCP 4.5 and 2061-2080 in RCP 8.5, respectively. Thus, climate change would bring more benefits than constrains for T. diversifolia dispersion. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has been monitored by applying different strategies, including SARS-CoV-2 detection with clinical testing or through wastewater-based epidemiology (WBE). We used the latter approach to follow SARS-CoV-2 dispersion in Tapachula city, located in Mexico's tropical southern border region. Tapachula is a dynamic entry point for people seeking asylum in Mexico or traveling to the USA. Clinical testing facilities for SARS-CoV-2 monitoring are limited in the city. A total of eighty water samples were collected from urban and suburban rivers and sewage and a wastewater treatment plant over 4 months in Tapachula. We concentrated viral particles with a PEG-8000-based method, performed RNA extraction, and detected SARS-CoV-2 particles through RT-PCR. We considered the pepper mild mottle virus as a fecal water pollution biomarker and analytical control. SARS-CoV-2 viral loads (N1 and N2 markers) were quantified and correlated with official regional statistics of COVID-19 bed occupancy and confirmed cases (r > 91%). Our results concluded that WBE proved a valuable tool for tracing and tracking the COVID-19 pandemic in tropical countries with similar water temperatures (21-29 °C). Monitoring SARS-CoV-2 through urban and suburban river water sampling would be helpful in places lacking a wastewater treatment plant or water bodies with sewage discharges., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)