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Full-Text Articles in Life Sciences
Water Stress Strengthens Mutualism Among Ants, Trees, And Scale Insects, Elizabeth G. Pringle, Erol Akc¸Ay, Ted K. Raab, Rodolfo Dirzo, Deborah M. Gordon
Water Stress Strengthens Mutualism Among Ants, Trees, And Scale Insects, Elizabeth G. Pringle, Erol Akc¸Ay, Ted K. Raab, Rodolfo Dirzo, Deborah M. Gordon
Ted K. Raab
Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant–plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners’ investments in a widespread ant–plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the …
Will Hubbard Brook Soils Be A Source Or Sink Of Carbon In A Changing Climate?, Chris E. Johnson
Will Hubbard Brook Soils Be A Source Or Sink Of Carbon In A Changing Climate?, Chris E. Johnson
Chris E Johnson
No abstract provided.
The Contribution Of Fe (Iii) And Humic Acid Reduction To Ecosystem Respiration In Drained Thaw Lake Basins Of The Arctic Coastal Plain, David A. Lipson, Ted K. Raab, Dominic Goria, Jaime Zlamal
The Contribution Of Fe (Iii) And Humic Acid Reduction To Ecosystem Respiration In Drained Thaw Lake Basins Of The Arctic Coastal Plain, David A. Lipson, Ted K. Raab, Dominic Goria, Jaime Zlamal
Ted K. Raab
Previous research showed that anaerobic respiration using iron (Fe) oxides as terminal electron acceptor contributed substantially to ecosystem respiration (ER) in a drained thaw lake basin (DTLB) on the Arctic coastal plain. As DTLB age, the surface organic layer thickens, progressively burying the Fe-rich mineral layers. We therefore hypothesized that Fe (III) availability and Fe reduction would decline with basin age. We studied four DTLB across an age gradient, comparing seasonal changes in the oxidation state of dissolved and extractable Fe pools and the estimated contribution of Fe reduction to ER. The organic layer thickness did not strictly increase with …
Metagenomic Insights Into Anaerobic Metabolism Along An Arctic Peat Soil Profile, David A. Lipson, John M. Haggerty, Archana Srinivas, Ted K. Raab, Shashank Sathe, Elizabeth A. Dinsdale
Metagenomic Insights Into Anaerobic Metabolism Along An Arctic Peat Soil Profile, David A. Lipson, John M. Haggerty, Archana Srinivas, Ted K. Raab, Shashank Sathe, Elizabeth A. Dinsdale
Ted K. Raab
A metagenomic analysis was performed on a soil profile from a wet tundra site in northern Alaska. The goal was to link existing biogeochemical knowledge of the system with the organisms and genes responsible for the relevant metabolic pathways. We specifically investigated how the importance of iron (Fe) oxides and humic substances (HS) as terminal electron acceptors in this ecosystem is expressed genetically, and how respiratory and fermentative processes varied with soil depth into the active layer and into the upper permafrost. Overall, the metagenomes reflected a microbial community enriched in a diverse range of anaerobic pathways, with a preponderance …
Diversity Of Plants And Animals In Mountain Systems In Tajikistan, Victor Roy Squires Dr, Neymatalo Safarov Dr
Diversity Of Plants And Animals In Mountain Systems In Tajikistan, Victor Roy Squires Dr, Neymatalo Safarov Dr
Victor Roy Squires Dr
Tajikistan, a landlocked country, is one of the world's centers of origin of cultivated plants and has a special role in the conservation of mountain biodiversity. The richness of biodiversity shows up at the genetic, species, population, and ecosystem levels. There are many relic and endemic species, with most of the components of biodiversity vulnerable to anthropogenic factors. Close cooperation across borders will be required for conservation of unique and threatened ecosystems in the Central Asian region. Proximate threats such as poaching, overfishing, illegal logging and overgrazing are causing irreversible damage to biodiversity in the Tajikistan hotspot. Threats stem from …
Classification Of The Alterations Of Beaver Dams To Headwater Streams In Northeastern Connecticut, U.S.A., Denise Burchsted, Melinda D. Daniels
Classification Of The Alterations Of Beaver Dams To Headwater Streams In Northeastern Connecticut, U.S.A., Denise Burchsted, Melinda D. Daniels
Denise Burchsted
Of the many types of barriers to water flow, beaver dams are among the smallest, typically lasting less than a decade and rarely exceeding 1.5 m in height. They are also among the most frequent and common obstructions in rivers, with a density often exceeding ten dams per km, a frequency of construction within a given network on a time scale of years, and a historic extent covering most of North America. Past quantification of the geomorphologic impact of beaver dams has primarily been limited to local impacts within individual impoundments and is of limited geographic scope. To assess the …
Insights Into Forest Soil Carbon Dynamics From Nuclear Magnetic Resonance Spectroscopy, Chris E. Johnson
Insights Into Forest Soil Carbon Dynamics From Nuclear Magnetic Resonance Spectroscopy, Chris E. Johnson
Chris E Johnson
No abstract provided.