Iron islands in the Amazon: investigating plant beta diversity of canga outcrops

PhytoKeys, Год журнала: 2020, Номер 165, С. 1 - 25

Опубликована: Окт. 28, 2020

The world’s largest mineral iron province, Serra dos Carajás, is home to an open vegetation known as canga, found on top of isolated outcrops rising out the Amazon rainforest. Over one thousand vascular plants species have been recorded in these canga sites, including 38 edaphic endemics. A new survey adds our investigation biogeographic relationships between sixteen and effect distance site pairs number shared species, regional turnover distribution patterns. Plant collecting expeditions westernmost site, de Campos São Félix do Xingu (SFX), were carried followed by identification all collected specimens creation a database, built perform biogeographical analyses. Floristic among sites investigated regarding their similarity, using multivariate correlation areas richness was tested, well geographical species. Vascular at SFX total 254 17 All are grouped with 25% minimum falls within large subgroup outcrops. does not change significantly but positively correlated area each outcrop. Meanwhile, endemic numbers decline when increases, possibly imposed barrier Our data suggest higher similarity species-richest opposed geographically nearby provide useful insight for drafting conservation compensation measures locations. size associated floristic diversity connectivity islands also plays role similarity.

Язык: Английский

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Acquiring Iron-Reducing Enrichment Cultures: Environments, Methods and Quality Assessments

Microorganisms, Год журнала: 2023, Номер 11(2), С. 448 - 448

Опубликована: Фев. 10, 2023

Lateritic duricrusts cover iron ore deposits and form spatially restricted, unique canga ecosystems endangered by mining. Iron cycling, i.e., the dissolution subsequent precipitation of iron, is able to restitute duricrusts, generating new habitats for biota in post-mining landscapes. As iron-reducing bacteria can accelerate this we aim retrieve microbial enrichment cultures suitable mediate large-scale restoration cangas. For that, collected water sediment samples from Carajás National Forest cultivated microorganisms therein using a specific medium. We measured potential reduce ferrozine assays, growth rate metabolic activity. Six out seven effectively reduced showing that different environments harbor bacteria. The most promising were obtained with repeated flooding drying cycles, periodically inundated grasslands plateau an mining waste pile characterized frequent soaking. Selected contained fermenting bacteria, such as Serratia Enterobacter. found higher cell density microorganism diversity. should be tested generate benefits biodiversity contribute more sustainable region.

Язык: Английский

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The Impact of Rhizospheric and Endophytic Bacteria on the Germination of Carajasia cangae: A Threatened Rubiaceae of the Amazon Cangas

Microorganisms, Год журнала: 2024, Номер 12(9), С. 1843 - 1843

Опубликована: Сен. 6, 2024

(Rubiaceae) is a narrow endemic species from the canga ecosystems of Carajás National Forest that facing extinction due to limited range and habitat disturbance hydroclimatological changes mining activities. This study examines influence rhizospheric endophytic bacteria on

Язык: Английский

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Drivers and ecological impacts of deforestation and forest degradation in the Amazon

Acta Amazonica, Год журнала: 2024, Номер 54(spe1)

Опубликована: Янв. 1, 2024

ABSTRACT Deforestation (the complete removal of an area’s forest cover) and degradation significant loss structure, functions, processes) are the result interaction between various direct drivers, often operating together. By 2018, Amazon had lost approximately 870,000 km2 its original cover, mainly due to expansion agriculture ranching. Other drivers include opening new roads, construction hydroelectric dams, exploitation minerals oil, urbanization. Impacts deforestation range from local global, including changes in landscape configuration, climate, biodiversity, regional impacts on hydrological cycles, global increase greenhouse gas emissions. Of remaining Amazonian forests, 17% degraded, corresponding 1,036,080 km2. Forest has anthropogenic understory fires, edge effects, selective logging, hunting, climate change. Degraded forests have significantly different microclimate, biodiversity as compared undisturbed ones. These tend higher tree mortality, lower carbon stocks, more canopy gaps, temperatures, humidity, wind exposure, exhibit compositional functional shifts both fauna flora. can come resemble their counterparts, but this depends type, duration, intensity, frequency disturbance event. In some cases may impede return a historic baseline. Avoiding further is crucial ensuring that they continue provide valuable life-supporting ecosystem services.

Язык: Английский

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Distinct Reproductive Strategy of Two Endemic Amazonian Quillworts

Diversity, Год журнала: 2021, Номер 13(8), С. 348 - 348

Опубликована: Июль 29, 2021

We examined the reproductive strategy of two Amazonian quillworts (Isoëtes cangae and Isoëtes serracarajensis), endemic threatened species canga ecosystems. Sexual propagation was by in vitro fertilization assays, while asexual tiller emission. is an outcrossing that reproduces exclusively spore germination able to propagate self- cross-fertilization. serracarajensis asexually emitting tillers from plant corm, despite producing male female sporangia. These distinct strategies different may be linked their contrasting habitats. inhabit a permanent oligotrophic lake with mild environmental changes, I. are found temporary ponds facing severe seasonal drought, where represent adaptive advantage short growth period during access water. also observed relationships between traits species, common production sporophytes high survival rates. Together, these results paramount importance for establishing conservation plans both considering advantages sexual maintain genetic diversity diligent management required do same propagated serracarajensis.

Язык: Английский

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