Christopher Boyd results 30
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The presence of soil hydrocarbon parameters (SHPs), including total petroleum hydrocarbons (TPHs), total organic carbon (TOC; %), and soil toxicity (EC50; mg L−1), can affect vegetation in several ways. This study assessed the impact of SHPs on vegetation in the Niger Delta using field-measured, leaf-scale hyperspectral data acquired across the region. Red-edge position (REP) and four hyperspectral vegetation indices (HVIs)—mN...
The Toxicology Investigators Consortium 2024 Annual ReportNARA Subscribed
Mesopredator release moderates trophic control of plant biomass in a Georgia salt marshNARA Subscribed
Predators regulate communities through top‐down control in many ecosystems. Because most studies of top‐down control last less than a year and focus on only a subset of the community, they may miss predator effects that manifest at longer timescales or across whole food webs. In southeastern US salt marshes, short‐term and small‐scale experiments indicate that nektonic predators (e.g., blue crab, fish, terrapins) facilitate th...
Temporal tracking of cysteine 34 oxidation of plasma albumin as a biomarker of muscle damage following a bout of eccentric exerciseNARA Subscribed
Purpose Exercise-induced muscle damage (EIMD) results in the generation of reactive oxygen species (ROS), but little is known about the temporal profile of change in ROS post-EIMD and how ROS levels relate to the onset of and recovery from EIMD. Our primary aim was to examine the effect of EIMD on the pattern of change in the blood level of thiol-oxidised albumin, a marker of oxidative stress. Methods Seven male participants w...
The Coastal Carbon Library and Atlas: Open source soil data and tools supporting blue carbon research and policyNARA Subscribed
Quantifying carbon fluxes into and out of coastal soils is critical to meeting greenhouse gas reduction and coastal resiliency goals. Numerous ‘blue carbon’ studies have generated, or benefitted from, synthetic datasets. However, the community those efforts inspired does not have a centralized, standardized database of disaggregated data used to estimate carbon stocks and fluxes. In this paper, we describe a data structure des...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Globally, tree fecundity exceeds productivity gradientsNARA Subscribed
Lack of tree fecundity data across climatic gradients precludes the analysis of how seed supply contributes to global variation in forest regeneration and biotic interactions responsible for biodiversity. A global synthesis of raw seedproduction data shows a 250‐fold increase in seed abundance from cold‐dry to warm‐wet climates, driven primarily by a 100‐fold increase in seed production for a given tree size. The modest (three...
Motivation The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community‐led open‐source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal...
Organisms are projected to face unprecedented rates of change in future ocean conditions due to anthropogenic climate‐change. At present, marine life encounters a wide range of environmental heterogeneity from natural fluctuations to mean climate change. Manipulation studies suggest that biota from more variable marine environments have more phenotypic plasticity to tolerate environmental heterogeneity. Here, we consider curre...
Spatial variation in life‐history trade‐offs results in an ideal free distribution in Black Brant GeeseNARA Subscribed
Ideal free distribution theory predicts that individuals distribute themselves so fitness is equal among patches. In this paper we evaluate all components of adult fitness to assess the hypothesis that individuals distribute themselves among seven brood‐rearing areas so that trade‐offs among different life history traits result in equal mean fitness among individuals using different areas. We used estimates of vital rates (clu...
Delphinid whistle production and call matching during playback of simulated military sonarNARA Subscribed
In 2007 and 2008, controlled exposure experiments were performed in the Bahamas to study behavioral responses to simulated mid‐frequency active sonar (MFA) by three groups of odontocetes: false killer whales, Pseudorca crassidens ; short‐finned pilot whales, Globicephala macrorhynchus ; and melon‐headed whales, Peponocephala electra . An individual in each group was tagged with a Dtag to record acoustic and movement data. Duri...
Forest Management, Engineering, and Operations / Global Competency and Issues in Contemporary EducationNARA Subscribed
31Maps depicting spatial variation in wood properties are important for forest product industries as they aid decision making regarding raw material procurement, can assist in product categorization and help improve utilization. Loblolly pine is an important commercial species grown throughout the southern Unites States of America (USA). Wood Quality Consortium (WQC)—a joint collaboration between the University of Georgia, USD...
Anthropogenically mediated decreases in pH , termed ocean acidification ( OA ), may be a major threat to marine organisms and communities. Research has focussed mainly on tropical coral reefs, but temperate reefs play a no less important ecological role in colder waters, where OA effects may first be manifest. Herein, we report that trends in pH at the surface of three ecologically important cold‐water calcifiers (a primary pr...