bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plant genotype influences aquatic‐terrestrial ecosystem linkages through timing and composition of insect emergence
Authors: Compson Zacchaeus G. , Hungate Bruce A. , Whitham Thomas G. , Meneses Nashelly , Busby Posy E. , Wojtowicz Todd , Ford Audrey C. , Adams Kenneth J. , Marks Jane C. 
Published: June 2016

AbstractTerrestrial leaf litter provides aquatic insects with an energy source and habitat structure, and species differences in litter can influence aquatic insect emergence. Emerging insects also provide energy to riparian predators. We hypothesized that plant genetics would influence the composition and timing of emerging insect communities among individual genotypes ofPopulus angustifoliavarying in litter traits. We also compared the composition and timing of emerging insect communities on litter from mixed genotypes of three cross types of a hybridizing cottonwood complex:P. angustifolia,P. fremontii, and their F1hybrids. Using litter harvested from an experimental common garden, we measured emerging insect community composition, abundance, and production for 12 weeks in large litter packs affixed with emergence traps. Five major findings emerged. (1) In support of the genetic similarity hypothesis, we found that, amongP. angustifoliatree genotypes, litter from more closely related genotypes had more similar litter thickness, nitrogen concentrations, decomposition rates, and emerging insect communities. (2) Genetic similarity was not correlated with other litter traits, although the litter fungal community was a strong predictor of emerging insect communities. (3) Litter decomposition rate, which was the strongest predictor of emerging aquatic insect communities, was influenced by litter thickness, litter N, and the litter fungal community. (4) In contrast to strong community composition differences amongP. angustifoliagenotypes, differences in community composition betweenP. fremontiiandP. angustifoliawere only marginally significant, and communities on F1hybrids were indistinguishable fromP. angustifoliadespite genetic and litter trait differences. (5) Mixed litter packs muted the genetic effects observed in litter packs consisting of single genotypes. These results demonstrate that the genetic structure of riparian forests can affect the composition and timing of aquatic insect emergence. Because many riparian trees are clonal, includingP. angustifolia, large clone size is likely to result in patches of genetically structured leaf litter that may influence the timing and composition of insect emergence within watersheds. Riparian restoration efforts incorporating different tree genotypes could also influence the biodiversity of emerging aquatic insects. Our work illustrates the importance of plant genes for community and ecosystem processes in riparian corridors.
Population dynamics of desert mammals: similarities and contrasts within a multispecies assemblage
Authors: Greenville Aaron C. , Wardle Glenda M. , Nguyen Vuong , Dickman Chris R. 
Published: June 2016

AbstractUnderstanding the temporal and spatial dynamics of species populations remains a key focus of population biology, providing vital insight into the drivers that influence demography and into sub‐populations that are vulnerable to extinction. Across regional landscapes, spatially separated sub‐populations may fluctuate in synchrony, or exhibit sub‐structuring due to subtle differences in local intrinsic and extrinsic factors. Using a long‐term data set (17–22 yr) obtained from a large (8000 km2) study region in arid central Australia, we tested firstly for regional synchrony in annual rainfall and the dynamics of five small mammal species across nine widely separated sites. Using Moran's theorem, we predicted that the spatial correlation between the regional sub‐populations of these species would equal that between local density‐independent conditions (annual rainfall). For species that showed synchronous spatial dynamics, we then used multivariate state‐space (MARSS) models to predict that regional rainfall would be positively associated with their populations, whereas species with asynchronous sub‐populations would be influenced largely by other factors. For these latter species, we used MARSS models to test four hypotheses. These were that sub‐population structures: (1) were asynchronous and governed by local site‐specific factors, (2) differed between oasis and non‐oasis sites, (3) differed between burnt and unburnt sites, and (4) differed between three sub‐regions with different rainfall gradients. We found that the spatial population dynamics of our study small mammals differed between and within families. Two species of insectivorous dasyurid marsupials showed asynchronous dynamics, which most likely tracked local conditions, whereas a larger carnivorous marsupial and two species of rodents had strongly synchronous dynamics. These latter species exhibited similar spatial correlations to local and regional rainfall events, providing evidence that the Moran effect operates for some, but not all, species in this arid system. Our results suggest that small mammal populations do not respond in similar ways to shared environmental drivers in arid regions, and hence will vary in their responses to climate change. As arid lands globally are predicted to face climatic shifts that will exacerbate rainfall‐drought cycles, we suggest that future work focuses on exploring these responses at different spatial scales across multiple dryland taxa.
Species and habitats in danger: estimating the relative risk posed by oil spills in the northern Baltic Sea
Authors: Helle Inari , Jolma Ari , Venesjärvi Riikka 
Published: June 2016

AbstractLarge‐scale oil spills can have adverse effects on biodiversity in coastal areas where maritime oil transportation is intense. In this article we conducted a spatial risk assessment to study the risk that potential tanker accidents pose to threatened habitat types and species living in the northern Baltic Sea, which has witnessed a rapid increase in maritime oil transportation within the past two decades. We applied a probabilistic method, which combines three components: a Bayesian network describing tanker accidents and uncertainties related to them, probabilistic maps showing the movement of oil, and a database of threatened species and habitats in the area. The results suggest that spatial risk posed by oil spills varies across the area, and does not correspond, for example, to the frequency of accidents in a given area. The relative risk is highest for seashore meadows, which is important to take into account when managing these habitats. Our analysis underlines the importance of a thorough risk assessment, which is not only based solely on one or two specific factors such as accident probabilities or the trajectories of spilled oil but also contains as broad a view of the consequences as possible. We believe that the probabilistic methodology applied in the study will be of high interest to people who have to cope with uncertainties typical for environmental risk assessment and management.
Convergent diversity and trait composition in temporary streams and ponds
Authors: Schriever Tiffany A. , Lytle David A. 
Published: June 2016

AbstractHydrology is the main environmental filter in aquatic ecosystems and may result in shared tolerances and functional traits among species in disparate ecosystems. We analyzed the associations between taxonomic and functional facets of diversity within aquatic ecosystems (ponds vs. streams) across a hydroperiod gradient (1–365 d) to untangle the hydrologic drivers of aquatic invertebrate diversity. We used invertebrate assemblage data from seven arid‐land streams in southeastern Arizona, United States collected over 2 yr and nine temperate woodland ponds in Ontario, Canada collected over 2 yr. Our results showed that although invertebrate assemblages from streams and ponds differ taxonomically, hydroperiod had similar influence on invertebrate trait structure regardless of biogeographic and habitat differences. Streams and ponds independently showed strong positive relationships between functional richness and taxonomic richness; however, the relationship showed a shallower slope in ponds, indicating higher functional redundancy. Intermittent ponds and streams tended to have lower functional and taxonomic richness than their perennial counterparts, but harbored greater beta diversity. Our results suggest that even though ponds and streams are fundamentally different habitats with distinct faunas and unique ecological processes, hydrology produces convergent patterns in both trait composition and diversity patterns.
Population trends for North American winter birds based on hierarchical models
Authors: Soykan Candan U. , Sauer John , Schuetz Justin G. , LeBaron Geoffrey S. , Dale Kathy , Langham Gary M. 
Published: June 2016

AbstractManaging widespread and persistent threats to birds requires knowledge of population dynamics at large spatial and temporal scales. For over 100 yrs, the Audubon Christmas Bird Count (CBC) has enlisted volunteers in bird monitoring efforts that span the Americas, especially southern Canada and the United States. We employed a Bayesian hierarchical model to control for variation in survey effort among CBC circles and, using CBC data from 1966 to 2013, generated early‐winter population trend estimates for 551 species of birds. Selecting a subset of species that do not frequent bird feeders and have ≥25% range overlap with the distribution of CBC circles (228 species) we further estimated aggregate (i.e., across species) trends for the entire study region and at the level of states/provinces, Bird Conservation Regions, and Landscape Conservation Cooperatives. Moreover, we examined the relationship between ten biological traits—range size, population size, migratory strategy, habitat affiliation, body size, diet, number of eggs per clutch, age at sexual maturity, lifespan, and tolerance of urban/suburban settings—and CBC trend estimates. Our results indicate that 68% of the 551 species had increasing trends within the study area over the interval 1966–2013. When trends were examined across the subset of 228 species, the median population trend for the group was 0.9% per year at the continental level. At the regional level, aggregate trends were positive in all but a few areas. Negative population trends were evident in lower latitudes, whereas the largest increases were at higher latitudes, a pattern consistent with range shifts due to climate change. Nine of 10 biological traits were significantly associated with median population trend; however, none of the traits explained >34% of the deviance in the data, reflecting the indirect relationships between population trend estimates and species traits. Trend estimates based on the CBC are broadly congruent with estimates based on the North American Breeding Bird Survey, another large‐scale monitoring program. Both of these efforts, conducted by citizen scientists, will be required going forward to ensure robust inference about population dynamics in the face of climate and land cover changes.
Testing the trait‐based community framework: Do functional traits predict competitive outcomes?
Authors: Funk Jennifer L. , Wolf Amelia A. 
Published: June 2016

AbstractPlant traits can be used to understand a range of ecological processes, including competition with invasive species. The extent to which native and invasive species are competing via limiting similarity or trait hierarchies has important implications for the management of invaded communities. We screened 47 native species that co‐occur with Festuca perennis, a dominant invader in California serpentine grassland, for traits pertaining to resource use and acquisition. We then grew F. perennis with 10 species spanning a range of functional similarity in pairwise competition trials. Functionally similar species did not have a strong adverse effect on F. perennis performance as would be expected by limiting similarity theory. Phylogenetic relatedness, which may integrate a number of functional traits, was also a poor predictor of competitive outcome. Instead, species with high specific root length, low root‐to‐shoot biomass ratio, and low leaf nitrogen concentration were more effective at suppressing the growth of F. perennis. Our results suggest that fitness differences (i.e., trait hierarchies) may be more important than niche differences (i.e., limiting similarity) in structuring competitive outcomes in this system and may be a promising approach for the restoration of invaded systems.
Regional diversity reverses the negative impacts of an alien predator on local species‐poor communities
Authors: Loewen Charlie J. G. , Vinebrooke Rolf D. 
Published: June 2016

AbstractSpecies diversity is often an implicit source of biological insurance for communities against the impacts of novel perturbations, such as the introduction of an invasive species. High environmental heterogeneity (e.g., a mountainous gradient) is expected to beget greater regional species diversity and variation in functional traits related to environmental tolerances. Thus, heterogeneous metacommunities are expected to provide more tolerant colonists that buffer stressed local communities in the absence of dispersal limitation. We tested the hypothesis that importation of a regional zooplankton pool assembled from a diverse array of lakes and ponds lessens the impacts of a novel predator on local species‐poor alpine communities by increasing response diversity (i.e., diversity of tolerances to environmental change) as mediated by variation in functional traits related to predator evasion. We also tested whether impacts varied with temperature, as warming may modify (e.g., dampen or amplify) invasion effects. An eight‐week factorial experiment ([fishless vs. introducedOncorhynchus mykiss(rainbow trout)] × [ambient temperature vs. heated] × [local vs. local + regional species pool]) was conducted using 32 1,000‐L mesocosms. Associations between experimental treatments and species functional traits were tested by R‐mode linked to Q‐mode (RLQ) and fourth‐corner analyses. Although the introduced predator suppressed local species richness and community biomass, colonization by several montane zooplankters reversed these negative effects, resulting in increased species diversity and production. Invasion resistance was unaffected by higher temperatures, which failed to elicit any significance impacts on the community. We discovered that the smaller body sizes of imported species drove functional overcompensation (i.e., increased production) in invaded communities. The observed ecological surprise showed how regionally sourced biodiversity from a highly heterogeneous landscape can offset, and even reverse, the local negative impacts of an invasive species. Further, prey body size was found to be a key species trait mediating the ecological impacts of the aquatic invasive predator. Our study highlights the novel application of a functional approach to understanding the impacts of biological invasions, using species traits that pertain directly to potential responses to exotic species.
Cold‐evoked potentials – Ready for clinical use?
Authors: Hüllemann P. , Nerdal A. , Binder A. , Helfert S. , Reimer M. , Baron R. 
Published: June 2016

AbstractBackgroundCold‐evoked potentials (CEPs) are known to assess the integrity of A‐delta fibres and the spinothalamic tract. Nevertheless, the clinical value was not investigated previously. The aim of this study was to measure CEPs in 16 healthy subjects from the face, hand and foot sole and to investigate whether CEPs reliably detect A‐delta fibre abnormalities.MethodsSwift cold stimuli were applied to the skin with a commercially available thermode, which cooled down from 30 to 25 °C in approximately 0.5 s. CEP latencies (N1, N2 and P2) and amplitudes (N1, N2/P2) were recorded with EEG. Reversible A‐fibre function loss was induced by applying a selective A‐fibre block at the superficial radial nerve.ResultsIn all 16 subjects CEPs could be recorded from all locations; N2, P2 mean latencies were 276.4 ± 38.9 and 389.8 ± 52.5 (face), 318.6 ± 31.6 ms and 477.7 ± 43.6 (hand), and 627.6 ± 84.4 and 774.2 ± 94.0 (foot sole). N2/P2 amplitudes were 10.7 ± 4.1, 11.3 ± 4.1 and 7.5 ± 4.1 μV. During A‐fibre block no CEPs were detectable in the grand average, which restored 10 min after block removal.ConclusionsCEPs were reliably recorded in healthy subjects at the hand, face and foot. Experimentally induced reversible A‐delta fibre function loss was detected by CEPs. Functional recovery was assessed as well. This study is basis for further CEP evaluation studies and might be the first step for implementing CEPs in clinical routine for the early diagnosis of small‐fibre disease.What does this study add?

Cold‐evoked potentials are capable of reliably measuring A‐delta fibre integrity, loss of function and functional recovery in healthy subjects, which is an essential prerequisite for diagnostic use in patients with small‐fibre disease.
Torrefaction and Process Energy Budget Analysis of Powdered, De‐oiled, and In Situ Transesterified Flaxseed Cakes for Energy Generation
Authors: Ali Mehmood , Watson Ian A. 
Published: June 2016

AbstractEdible vegetable oil seeds are used to produce oil for human consumption and inedible vegetable oil seeds are used to produce biofuels; the residue cakes from the extraction process contain significant energy that can be utilised. This study is a continuation of previous work on oil extraction from flaxseed to produce biodiesel; herein, the residue cake from flaxseed was studied. Three different types of samples (powdered seeds, de‐oiled cake, and in situ transesterified cake of flaxseed) were torrefied (through slow pyrolysis), and the sample properties were characterized. The higher heating value (HHV=36.01±0.36 MJ kg−1) and bulk density (0.33±0.01 g cm−3) of the powdered seeds are higher compared to the other two samples (i.e. de‐oiled cake and in situ transesterified cake). The torrefied biomass was light weight losing its mechanical strength on treatment, making it easier to grind. It was observed that the biomass torrefied at 300 °C had a higher fraction of particles between sieve sizes (between 2.0 and 0.063 mm) compared to the biomass torrefied at 200 °C. The sieve sizes between 0.5 and 0.063 mm showed that more particles of the torrefied biomass treated at 300 °C were collected compared to that torrefied at 200 °C. Due to the loss of hydrogen and oxygen content and the removal of water, the carbon content in the torrefied biomass increased by 25.52, 24.51, and 22.69 % for the powdered seeds, de‐oiled cake, and in situ cake samples, respectively. The powdered seeds had a higher carbon and hydrogen content compared to the de‐oiled and in situ transesterified flaxseed cakes because the powdered seeds contained fatty acids. The powdered seeds had a higher concentration of CO2 gas liberated during treatment compared to the de‐oiled and in situ transesterified cakes. This was attributed to the powdered seeds having a higher concentration of volatile hydrocarbons and a lower ash content. It was observed that the energy ratios were reduced with respect to increasing temperature whereas the highest energy ratios were found for the powdered seeds.
Are My Professional Evaluation Dispositions to Be Found in My Early Life Experiences?
Authors: Stake Robert E. 
Published: June 2016

AbstractHaving searched for prescient stories from his early life, Robert Stake passes on these observations from recollections, interviews with David Williams, and symposium sessions of the American Evaluation Association in 2012 and 2013. He speaks of opposing views of evaluation held by his parents, perhaps eventually appearing in his writings. He reflects on ordinary evaluation decisions he made about getting married, going to graduate school, and raising children. He does not see such early experiences much paralleling or informing his professional evaluation theories and practices. Readers may see values he found extraprofessionally marking his professional work.
Thoughts About an Early Evaluation Life
Authors: Scriven Michael 
Published: June 2016

AbstractScriven describes how he believes the early death of his father, constant intercontinental moving he experienced as a child, and associated fractures in relationships he began with peers influenced his “attitude towards the value of reason,” which is his “main professional area of publication and evaluation.” He recounts stories of developing his own evaluation life by running away from home at age 14 (following his father's example); writing an award‐winning essay on quantitatively evaluating acts of valor (as he wanted to be a RAF pilot like his father); pursuing math, science, and philosophy in college; critiquing parapsychology; evaluating sports cars; exploring and teaching critical thinking; deciding where to go to university and where to work; and eventually being pulled into professional evaluation by being asked to work on a White House task force that included evaluating university courses and curricula on critical thinking; and collaborating with other early evaluation theorists.
Childhood Influences on My Work
Authors: House Ernie 
Published: June 2016

AbstractHouse tells stories about his childhood experiences with adults who were making what he felt were poor evaluations. He had similar evaluation experiences as a teacher and slowly developed his own views about how evaluation could be most fairly and appropriately accomplished in everyday life. He began applying these ideas and many others when he was put in charge of a national evaluation in the 1960s, drawing upon perspectives of many colleagues he assembled to give him advice. He retained a healthy skepticism that typifies all his work, based on the childhood convictions he developed through observing and defending himself from poor adult evaluations.
Connections, Themes, and Implications for the Future of Evaluation
Authors: Williams David Dwayne 
Published: June 2016

AbstractThis final article explores some of the unique and common connections the seven early and influential evaluators have made between their extraprofessional and professional evaluation lives, as reflected in their comments and stories in their individual articles and one prominent theme noted across all cases: These evaluators described how their values developed and eventually shaped their evaluation approaches. In addition, some subthemes are identified and questions for further study are posed. Following, in one page each, the seven authors review their colleagues’ articles and offer their own responses regarding what they learned from each other and what possible implications they foresee for future evaluation. Based on these reviews, readers are invited to think about possible implications for their own and their clients’ evaluation lives. The entire document invites readers to relate to evaluation less as a technology and more as a values‐based activity involving their own values and those of other participants in their evaluations.