Autor: |
Molina V; Programa de Biodiversidad y Departamento de Biología, Facultad de Ciencias Naturales y Exactas, Observatorio de Ecología Microbiana, Universidad de Playa Ancha, Valparaíso, Chile. veronica.molina@upla.cl., Eissler Y; Centro de Investigación y Gestión de Recursos Naturales, Instituto de Química y Bioquímica, Universidad de Valparaíso, Valparaíso, Chile., Cornejo M; Escuela de Ciencias del Mar e Instituto Milenio de Oceanografía Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile., Galand PE; Laboratoire d'Ecogéochimie des Environnements Benthiques (LECOB), Sorbonne Université, CNRS, Observatoire Océanologique de Banyuls, 66650, Banyuls/Mer, France., Dorador C; Laboratorio de Complejidad Microbiana y Ecología Funcional, Instituto de Antofagasta & Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile.; Centre for Biotechnology and Bioengineering, Santiago, Chile., Hengst M; Centre for Biotechnology and Bioengineering, Santiago, Chile.; Departamento de Ciencias Farmacéuticas, Facultad de Ciencias, Universidad Católica del Norte, Antofagasta, Chile., Fernandez C; Laboratoire d'Océanographie microbienne (LOMIC), Sorbonne Université, CNRS, Observatoire Océanologique de Banyuls, 66650, Banyuls/Mer, France.; FONDAP INCAR Center (15110027), PFB-31 COPAS Sur Austral, Departamento de Oceanografía, Universidad de Concepción, Concepción, Chile., Francois JP; Departamento de Geografía, Universidad de Playa Ancha, Valparaíso, Chile. |
Abstrakt: |
Northern Chile harbors different bioclimatic zones including hyper-arid and arid ecosystems and hotspots of microbial life, such as high altitude wetlands, which may contribute differentially to greenhouse gases (GHG) such as carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O). In this study, we explored ground level GHG distribution and the potential role of a wetland situated at 3800 m.a.s.l, and characterized by high solar radiation < 1600 W m -2 , extreme temperature ranges (-12 to 24 °C) and wind stress (< 17 m s -1 ). The water source of the wetland is mainly groundwater springs, which generates streams and ponds surrounded by peatlands. These sites support a rich microbial aquatic life including diverse bacteria and archaea communities, which transiently form more complex structures, such as microbial mats. In this study, GHG were measured in the water and above ground level air at the wetland site and along an elevation gradient in different bioclimatic areas from arid to hyper-arid zones. The microbiome from the water and sediments was described by high-throughput sequencing 16S rRNA and rDNA genes. The results indicate that GHG at ground level were variable along the elevation gradient potentially associated with different bioclimatic zones, reaching high values at the high Andean steppe and variable but lower values in the Atacama Desert and at the wetland. The water areas of the wetland presented high concentrations of CH 4 and CO 2 , particularly at the spring areas and in air bubbles below microbial mats. The microbial community was rich (> 40 phyla), including archaea and bacteria potentially active in the different matrices studied (water, sediments and mats). Functional microbial groups associated with GHG recycling were detected at low frequency, i.e., < 2.5% of total sequences. Our results indicate that hyper-arid and arid areas of northern Chile are sites of GHG exchange associated with various bioclimatic zones and particularly in aquatic areas of the wetland where this ecosystem could represent a net sink of N 2 O and a source for CH 4 and CO 2 . |