RESUMEN
Arbuscular mycorrhizal fungi (AMF) are important during revegetation of mining sites, but few studies compared AMF community in revegetated sites with pristine adjacent ecosystems. The aim of this study was to assess AMF species richness in a revegetated iron-mining site and adjacent ecosystems and to relate AMF occurrence to soil chemical parameters. Soil samples were collected in dry and rainy seasons in a revegetated iron-mining site (RA) and compared with pristine ecosystems of forest (FL), canga (NG), and Cerrado (CE). AMF species were identified by spore morphology from field and trap cultures and by LSU rDNA sequencing using Illumina. A total of 62 AMF species were recovered, pertaining to 18 genera and nine families of Glomeromycota. The largest number of species and families were detected in RA, and Acaulospora mellea and Glomus sp1 were the most frequent species. Species belonging to Glomeraceae and Acaulosporaceae accounted for 42%-48% of total species richness. Total number of spores and mycorrhizal inoculum potential tended to be higher in the dry than in the rainy season, except in RA. Sequences of uncultured Glomerales were dominant in all sites and seasons and five species were detected exclusively by DNA-based identification. Redundancy analysis evidenced soil pH, organic matter, aluminum, and iron as main factors influencing AMF presence. In conclusion, revegetation of the iron-mining site seems to be effective in maintaining a diverse AMF community and different approaches are complementary to reveal AMF species, despite the larger number of species being identified by traditional identification of field spores.
Asunto(s)
Ecosistema , Restauración y Remediación Ambiental , Micorrizas/fisiología , Microbiología del Suelo , Biodiversidad , Bosques , Hierro , Minería , Raíces de Plantas/microbiología , Esporas FúngicasRESUMEN
The term rheophyte describes a biological group of flood-tolerant plants that are confined to the beds of swift-running streams and rivers in nature and grow up to flood level, but not beyond the reach of regularly occurring flash floods. Although over 35 yr have passed since the first global census of rheophytes, no updates have been recorded regarding the number of taxa in this biological group in seed plants. Therefore, the present work aimed to (1) review the main topics associated with rheophytism (e.g., morphological characteristics, genetic studies, geographic distribution, conservation, and evolutionary aspects); (2) provide an updated checklist of rheophytes distributed around the world considering the two main groups in seed plants (gymnosperms and angiosperms); (3) demonstrate the distribution of rheophytism in the angiosperm phylogeny; and (4) estimate the geographical distribution and richness of selected taxa on the world map for the first time. All data compiled for the present study originated from a search of peer-reviewed articles, secondary literature (theses, dissertations, reports, books, and floras), and electronic facilities. We compiled a data set composed of four taxa in gymnosperms (Podocarpaceae family) and 1,368 taxa (including obligate, facultative, and unclassified rheophytes) distributed in 114 families and 508 genera in angiosperms. Most of the studied taxa belong to eudicotyledons (72.81%), while 1.46% belong to magnoliids, and 25.73% belong to monocotyledons. The families with the highest number of taxa in descending order are Podostemaceae, Araceae, Myrtaceae, Rubiaceae, Asteraceae, Apocynaceae, Arecaceae, Fabaceae, Phyllanthaceae, and Poaceae. Of the 114 families plotted in angiosperm phylogeny, at least 80 harbor obligate rheophytes. The geographical distribution of rheophytes in angiosperms, as expected based on the first census of this biological group, is mainly in the tropical and subtropical regions. The high richness of rheophytic taxa was mostly found in southern Mexico, southern China, Borneo, and northern and eastern Australia. In contrast, the geographical distribution of rheophytes in gymnosperms is restricted to New Caledonia and Tasmania. The present study will help to advance knowledge regarding the diversity of rheophytes in angiosperms and gymnosperms while drawing attention to this biological group, which has often been overlooked. There are no copyright restrictions. Please cite this data paper when the data are used in publications and teaching events.