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Phosphorus and base cations drive contrasting root dynamics in a central Amazon forestNARA Subscribed
Background and aims In highly weathered soils of central Amazonia, where nutrients such as phosphorus (P) and base cations are scarce, fertilization experiments have demonstrated above- and belowground effects on total net primary productivity (NPP). This study examined how fine root stocks and turnover responded to added nutrients over a two-year period. We predicted that adding a limiting nutrient would decrease fine root st...
Dispersal is one of the most important aspects of animal behavior and can have far‐reaching consequences for organismal ecology and evolution. Despite recent theoretical advances in understanding why individuals within the same population vary in dispersal behavior, relatively few studies have empirically evaluated the long‐term causes and consequences of variable dispersal within natural populations. In this study, we used li...
Redfield revisited: Insights into freshwater seston carbon : nitrogen : phosphorus stoichiometryNARA Subscribed
Seston carbon (C), nitrogen (N), and phosphorus (P) stoichiometry plays a fundamental role in aquatic ecosystems, influencing nutrient cycling, primary and secondary production, and trophic interactions. In freshwater systems such as lakes, P limitation is more common, whereas in marine environments, N more frequently limits primary production, reflecting different nutrient limitation patterns across aquatic ecosystems. The Re...
Tropical ecosystems contain the world's largest biodiversity of vascular plants. Yet, our understanding of tropical functional diversity and its contribution to global diversity patterns is constrained by data availability. This discrepancy underscores an urgent need to bridge data gaps by incorporating comprehensive tropical root data into global datasets. Here, we provide a database of tropical root characteristics. This new...
Nitrogen fixation may not alleviate stoichiometric imbalances that limit primary production in eutrophic lake ecosystemsNARA Subscribed
Ecosystem‐scale primary production may be proximately limited by nitrogen (N) but ultimately limited by phosphorus (P) because N 2 fixation contributes new N that accumulates relative to P at ecosystem scales. However, the duration needed to transition between proximate N limitation and ultimate P limitation remains unknown for most ecosystems, including lakes. Here we present the results of a fully replicated, multi‐annual la...
Coefficients in Taylor's law increase with the time scale of water clarity measurements in a global suite of lakesNARA Subscribed
Identifying the scaling rules describing ecological patterns across time and space is a central challenge in ecology. Taylor's law of fluctuation scaling, which states that the variance of a population's size or density is proportional to a positive power of the mean size or density, has been widely observed in population dynamics and characterizes variability in multiple scientific domains. However, it is unclear if this phen...
Tropical root responses to global changes: A synthesisNARA Subscribed
Tropical ecosystems face escalating global change. These shifts can disrupt tropical forests' carbon (C) balance and impact root dynamics. Since roots perform essential functions such as resource acquisition and tissue protection, root responses can inform about the strategies and vulnerabilities of ecosystems facing present and future global changes. However, root trait dynamics are poorly understood, especially in tropical e...
Fine roots stimulate nutrient release during early stages of leaf litter decomposition in a Central Amazon rainforestNARA Subscribed
Purpose Large parts of the Amazon rainforest grow on weathered soils depleted in phosphorus and rock-derived cations. We tested the hypothesis that in this ecosystem, fine roots stimulate decomposition and nutrient release from leaf litter biochemically by releasing enzymes, and by exuding labile carbon stimulating microbial decomposers. Methods We monitored leaf litter decomposition in a Central Amazon tropical rainforest, wh...
Lakes in human‐dominated landscapes often face high loads of nutrients that may alter ecosystem function. High N loads relative to P are especially common in agricultural watersheds, where nitrate (NO 3 ) in particular is elevated due to fertilizer application and runoff. While past research has focused extensively on the impact of nutrient loads on reductions in water quality, we still lack assessment of the impact of high N...
Full lifetime perspectives on the costs and benefits of lay‐date variation in tree swallowsNARA Subscribed
Animals must balance various costs and benefits when deciding when to breed. The costs and benefits of breeding at different times have received much attention, but most studies have been limited to investigating short‐term season‐to‐season fitness effects. However, breeding early, versus late, in a season may influence lifetime fitness over many years, trading off in complex ways across the breeder’s lifespan. In this study,...
Plasticity in nitrogen uptake among plant species with contrasting nutrient acquisition strategies in a tropical forestNARA Subscribed
Nitrogen (N) availability influences the productivity and distribution of plants in tropical montane forests. Strategies to acquire soil N, such as direct uptake of organic compounds or associations with root symbionts to enhance N acquisition in exchange for carbon (C), may facilitate plant species coexistence and ecosystem N retention. Alternatively, rapid microbial turnover of soil N forms in tropical soils might promote fl...
Seedling performance trade‐offs influencing habitat filtering along a soil nutrient gradient in a tropical forestNARA Subscribed
Recent studies have provided evidence that trade‐offs in biomass allocation, resource‐use efficiency, and anti‐herbivore defense influence seedling performance and distribution across soil types. Our previous research suggested that soil nutrient availability acted as a filter for understory palm community assembly and species coexistence in a lower montane forest in western Panama. Here, we experimentally tested three potenti...
Antiretroviral drugs induce oxidative stress and neuronal damage in the central nervous systemNARA Subscribed
HIV-associated neurocognitive disorder (HAND), characterized by a wide spectrum of behavioral, cognitive, and motor dysfunctions, continues to affect approximately 50 % of HIV(+) patients despite the success of combination antiretroviral drug therapy (cART) in the periphery. Of note, potential toxicity of antiretroviral drugs in the central nervous system (CNS) remains remarkably underexplored and may contribute to the persist...