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1. Considerations of variability and power for long-term monitoring of stream fish assemblages

Author:
George, Scott D.; Stich, Daniel S.; Baldigo, Barry P.
Source:
Canadian journal of fisheries and aquatic sciences 2021 v.78 no.3 pp. 301-311
ISSN:
1205-7533
Subject:
temporal variation,   etc   ; fish; fish communities;     Show all 3 Subjects
Abstract:
... Little attention has been given to optimizing statistical power for monitoring stream fish assemblages. We explored the relationship between temporal variability and statistical power using 34 metrics from fish community data collected annually at six sites over 10 years via electrofishing. Metric variability differed by the life stage and group of species considered, use of abundance or mass data ...
DOI:
10.1139/cjfas-2020-0013

2. Arsenic release and transport during oxidative dissolution of spatially-distributed sulfide minerals

Author:
Battistel, Maria; Stolze, Lucien; Muniruzzaman, Muhammad; Rolle, Massimo
Source:
Journal of hazardous materials 2021 v.409 pp. 124651
ISSN:
0304-3894
Subject:
temporal variation,   etc   ; arsenic; hydrochemistry; models; oxidation; sulfides;     Show all 6 Subjects
Abstract:
... The oxidative dissolution of sulfide minerals, naturally present in the subsurface, is one of the major pathways of arsenic mobilization. This study investigates the release and fate of arsenic from arsenopyrite and löllingite oxidation under dynamic redox conditions. We performed multidimensional flow-through experiments focusing on the impact of chemical heterogeneity on arsenic mobilization and ...
DOI:
10.1016/j.jhazmat.2020.124651

3. Context Effect on Temporal Resolution of Olfactory–Gustatory, Visual–Gustatory, and Olfactory–Visual Synchrony Perception

Author:
Gotow, Naomi; Kobayakawa, Tatsu
Source:
Chemosensory perception 2021 v.14 no.1 pp. 27-40
ISSN:
1936-5802
Subject:
temporal variation,   etc   ; flavor; odors; people; taste;     Show all 5 Subjects
Abstract:
... INTRODUCTION: If odor and taste are presented in a context with high temporal proximity, they are more likely to be perceived as a flavor object. However, if odor and taste are presented in a context with low temporal proximity as well as a context with high temporal proximity, they may be less likely to be perceived as a flavor object. Based on these expectations, we hypothesized that sensitivity ...
DOI:
10.1007/s12078-020-09282-z

4. Variation cascades: resource pulses and top‐down effects across time scales

Author:
Simon, Franz W.; Vasseur, David A.
Source:
Ecology 2021 v.102 no.4 pp. e03277
ISSN:
0012-9658
Subject:
temporal variation,   etc   ; ecosystems; food chain; primary productivity;     Show all 4 Subjects
Abstract:
... Top‐down and bottom‐up theories of trophic control have been fundamental to our understanding of community dynamics and structure. However, most ecological theories have focused on equilibrium dynamics and do not provide predictions for communities’ responses in temporally fluctuating environments. By deriving the frequency response of populations in different trophic communities, we extend the to ...
DOI:
10.1002/ecy.3277

5. Population responses to observed climate variability across multiple organismal groups

Author:
Christie, Le Coeur; Jonathan, Storkey; Satu, Ramula
Source:
Oikos 2021 v.130 no.3 pp. 476-487
ISSN:
0030-1299
Subject:
temporal variation,   etc   ; longevity; population growth; temperature;     Show all 4 Subjects
Abstract:
... A major challenge in ecology is to understand how populations are affected by increased climate variability. Here, we assessed the effects of observed climate variability on different organismal groups (amphibians, insects, mammals, herbaceous plants and reptiles) by estimating the extent to which interannual variation in the annual population growth rates (CVλ) and the absolute value of the long‐ ...
DOI:
10.1111/oik.07371

6. Ecological status of coralligenous assemblages: Ten years of application of the ESCA index from local to wide scale validation

Author:
Piazzi, L.; Gennaro, P.; Cecchi, E.; Bianchi, C.N.; Cinti, M.F.; Gatti, G.; Guala, I.; Morri, C.; Sartoretto, F.; Serena, F.; Montefalcone, M.
Source:
Ecological indicators 2021 v.121 pp. 107077
ISSN:
1470-160X
Subject:
temporal variation,   etc   ; anthropogenic activities; Mediterranean Sea;     Show all 3 Subjects
Abstract:
... This paper aims at collating and reviewing all data collected using the ESCA (Ecological Status of Coralligenous Assemblages) index from 2009 to 2018 during different local applications, in order to evaluate at large spatial scale its effectiveness and temporal variability. To this scope, the large-scale response of ESCA to anthropogenic disturbance was tested comparing ESCA values calculated at 4 ...
DOI:
10.1016/j.ecolind.2020.107077

7. Relying on repeated biospecimens to reduce the effects of classical-type exposure measurement error in studies linking the exposome to health

Author:
Agier, Lydiane; Slama, Rémy; Basagaña, Xavier
Source:
Environmental research 2020 v.186 pp. 109492
ISSN:
0013-9351
Subject:
temporal variation,   etc   ; biomarkers; calibration;     Show all 3 Subjects
Abstract:
... The exposome calls for assessing numerous exposures, typically using biomarkers with varying amounts of measurement error, which can be assumed to be of classical type. We evaluated the impact of classical-type measurement error on the performance of exposome-health studies, and the efficiency of two measurement error correction methods relying on the collection of repeated biospecimens: within-su ...
DOI:
10.1016/j.envres.2020.109492

8. Betting on Bitcoin: Does gambling volume on the blockchain explain Bitcoin price changes?

Author:
Conlon, Thomas; McGee, Richard J.
Source:
Economics letters 2020 v.191 pp. 108727
ISSN:
0165-1765
Subject:
temporal variation,   etc   ; prices;     Show all 2 Subject
Abstract:
... We measure lottery appetite using historical gaming transaction data of Bitcoin holders. Changes in the volume spent on the most lottery-like gambling wallet explain 32% of variation in the returns to the BTC price pre-2016, but this effect disappears post-2016. ...
DOI:
10.1016/j.econlet.2019.108727

9. Spatial and temporal variation of compositional, functional, and phylogenetic diversity in ectoparasite infracommunities harboured by small mammals

Author:
Krasnov, Boris R.; Vinarski, Maxim V.; Korallo-Vinarskaya, Natalia P.; Shenbrot, Georgy I.; Khokhlova, Irina S.
Source:
Parasitology 2021 v.148 no.6 pp. 685-695
ISSN:
1469-8161
Subject:
temporal variation,   etc   ; Siphonaptera; ecosystems; ectoparasites; hosts; mites; parasitology; phylogeny;     Show all 8 Subjects
Abstract:
... We studied patterns of compositional, functional, and phylogenetic α- and β-diversity in flea and gamasid mite infracommunities of small Siberian mammals, taking into account host-associated (species) and environmental (biome or sampling period) factors. We asked: (a) How do these factors and their interactions affect infracommunity diversity? (b) Does infracommunity composition, in terms of speci ...
DOI:
10.1017/S0031182021000299

10. Calculating population reductions of invertebrate species for IUCN Red List assessments

Author:
Akçakaya, H. Reşit; Hochkirch, Axel; Bried, Jason T.; van Grunsven, Roy H. A.; Simaika, John P.; De Knijf, Geert; Henriques, Sérgio
Source:
Journal of insect conservation 2021 v.25 no.2 pp. 377-382
ISSN:
1366-638X
Subject:
temporal variation,   etc   ; expert opinion; extinction; insects; invertebrates; risk;     Show all 6 Subjects
Abstract:
... Population reductions are often used to assess extinction risk of species in the IUCN Red List. Guidelines for Red List assessments describe specific methods for calculating the amount of reduction for species with strongly fluctuating populations. Recently, an alternative approach that involves expert opinion has been suggested for calculating population reduction in insect species. We argue that ...
DOI:
10.1007/s10841-021-00303-0

11. Intrinsic timescales of variability in a marine plankton model

Author:
Mayersohn, Benjamin; Smith, K. Shafer; Mangolte, Inès; Lévy, Marina
Source:
Ecological modelling 2021 v.443 pp. 109446
ISSN:
0304-3800
Subject:
temporal variation,   etc   ; biomass; climate models; community structure; phytoplankton; zooplankton;     Show all 6 Subjects
Abstract:
... Phytoplankton are known to exhibit temporal variability in biomass and community composition. While physically driven sources of variability have been studied extensively, ecosystems often exhibit complicated intrinsic dynamics that are not as well understood. As a first step towards assessing the contribution of this intrinsic variability to the total variability in the ocean, we examine the temp ...
DOI:
10.1016/j.ecolmodel.2021.109446

12. Ecosystem based multi-species management using Empirical Dynamic Programming

Author:
Brias, Antoine; Munch, Stephan B.
Source:
Ecological modelling 2021 v.441 pp. 109423
ISSN:
0304-3800
Subject:
temporal variation,   etc   ; algorithms; ecosystems; nonlinear models; predation; time series analysis;     Show all 6 Subjects
Abstract:
... Control theory and stochastic dynamic programming have long been used to develop optimal single-species management policies. However, most species interact with others through competition and predation as parts of complex ecosystems. As a consequence, it is unclear how far from optimal the single species policies currently in use actually are. Moreover, there are as yet no scalable algorithms for ...
DOI:
10.1016/j.ecolmodel.2020.109423

13. Accession-specific flowering time variation in response to nitrate fluctuation in Arabidopsis thaliana

Author:
Yan, Fei-Hong; Zhang, Li-Ping; Cheng, Fang; Yu, Dong-Mei; Hu, Jin-Yong
Source:
Plant diversity 2021 v.43 no.1 pp. 78-85
ISSN:
2468-2659
Subject:
temporal variation,   etc   ; Arabidopsis thaliana; gene expression; nitrates; nitrogen; species diversity;     Show all 6 Subjects
Abstract:
... Flowering time, a key transition point from vegetative to reproductive growth, is regulated by an intrinsic complex of endogenous and exogenous signals including nutrient status. For hundreds of years, nitrogen has been well known to modulate flowering time, but the molecular genetic basis on how plants adapt to ever-changing nitrogen availability remains not fully explored. Here we explore how Ar ...
DOI:
10.1016/j.pld.2020.05.004

14. Multi‐scale biodiversity drives temporal variability in macrosystems

Author:
Patrick, Christopher J; McCluney, Kevin E; Ruhi, Albert; Gregory, Andrew; Sabo, John; Thorp, James H
Source:
Frontiers in ecology and the environment 2021 v.19 no.1 pp. 47-56
ISSN:
1540-9295
Subject:
temporal variation,   etc   ; data collection; ecosystems; equations; models; species diversity;     Show all 6 Subjects
Abstract:
... High temporal variability in environmental conditions, populations, and ecological communities can result in species extinctions and outbreaks of agricultural pests and disease vectors, as well as impact industries dependent on reliable provisioning of ecosystem services. Yet few empirical studies have focused on testing hypotheses about the drivers of ecological temporal variability at large spat ...
DOI:
10.1002/fee.2297

15. The characteristic time of ecological communities

Author:
Ontiveros, Vicente J.; Capitán, José A.; Casamayor, Emilio O.; Alonso, David
Source:
Ecology 2021 v.102 no.2 pp. e03247
ISSN:
0012-9658
Subject:
temporal variation,   etc   ; biogeography; community structure; stochastic processes; time series analysis;     Show all 5 Subjects
Abstract:
... A simple description of temporal dynamics of ecological communities may help us understand how community assembly proceeds, predict ecological responses to environmental disturbances, and improve the performance of biological conservation actions. Although community changes take place at multiple temporal scales, the variation of species composition and richness over time across communities and ha ...
DOI:
10.1002/ecy.3247

16. Experimentally validated study of the impact of operating strategies on power efficiency of a turbine array in a bi-directional tidal channel

Author:
Hachmann, Christoph; Stallard, Tim; Stansby, Peter; Lin, Binliang
Source:
Renewable energy 2021 v.163 pp. 1408-1426
ISSN:
0960-1481
Subject:
temporal variation,   etc   ; basins; energy; models; prediction; renewable energy sources; turbines;     Show all 7 Subjects
Abstract:
... Flexible operation across a wide range of operating conditions is required to maximise the contribution of tidal turbine arrays to the future energy mix. This study establishes a basin efficiency range of a small array of horizontal axis turbines between 0.45 and 0.79, with dependency on turbine operating point and flow direction. This range is largely due to variation of array thrust as array pow ...
DOI:
10.1016/j.renene.2020.06.090

17. Interspecific facilitation mediates the outcome of intraspecific interactions across an elevational gradient

Author:
Raath‐Krüger, Morgan J.; Schöb, Christian; McGeoch, Melodie A.; le Roux, Peter C.
Source:
Ecology 2021 v.102 no.1 pp. e03200
ISSN:
0012-9658
Subject:
temporal variation,   etc   ; Agrostis; Azorella; conspecificity; intraspecific competition; perennial grasses; reproduction;     Show all 7 Subjects
Abstract:
... Where interspecific facilitation favors the establishment of high densities of a beneficiary species, strong intraspecific competition may subsequently impede beneficiary performance. Consequently, the negative influence of intraspecific competition between beneficiary individuals could potentially outweigh the positive influence of interspecific facilitation when, for example, higher densities of ...
DOI:
10.1002/ecy.3200

18. Significant concurrent decrease in PM2.5 and NO2 concentrations in China during COVID-19 epidemic

Author:
Chu, Biwu; Zhang, Shuping; Liu, Jun; Ma, Qingxin; He, Hong
Source:
Journal of environmental sciences (China) 2021 v.99 pp. 346-353
ISSN:
1001-0742
Subject:
temporal variation,   etc   ; COVID-19 infection; air pollutants; China;     Show all 4 Subjects
Abstract:
... The strict control measures and social lockdowns initiated to combat COVID-19 epidemic have had a notable impact on air pollutant concentrations. According to observation data obtained from the China National Environmental Monitoring Center, compared to levels in 2019, the average concentration of NO₂ in early 2020 during COVID-19 epidemic has decreased by 53%, 50%, and 30% in Wuhan city, Hubei Pr ...
DOI:
10.1016/j.jes.2020.06.031

19. Urban Water Consumption at Multiple Spatial and Temporal Scales. A Review of Existing Datasets

Author:
Di Mauro, Anna; Cominola, Andrea; Castelletti, Andrea; Di Nardo, Armando
Source:
Water 2020 v.13 no.1
ISSN:
2073-4441
Subject:
temporal variation,   etc   ; data collection; water;     Show all 3 Subjects
Abstract:
... Over the last three decades, the increasing development of smart water meter trials and the rise of demand management has fostered the collection of water demand data at increasingly higher spatial and temporal resolutions. Counting these new datasets and more traditional aggregate water demand data, the literature is rich with heterogeneous urban water demand datasets. They are characterized by h ...
DOI:
10.3390/w13010036

20. Meiofauna in a Potential Deep-Sea Mining Area—Influence of Temporal and Spatial Variability on Small-Scale Abundance Models

Author:
Uhlenkott, Katja; Vink, Annemiek; Kuhn, Thomas; Gillard, Benjamin; Martínez Arbizu, Pedro
Source:
Diversity 2020 v.13 no.1
ISSN:
1424-2818
Subject:
temporal variation,   etc   ; Nematoda; fauna; sediments;     Show all 4 Subjects
Abstract:
... In large areas of the Clarion Clipperton Fracture Zone (northeast Pacific), exploration of deep-sea polymetallic nodules as a potential source of high-technology metals is ongoing. Deep-sea mining may have a severe impact on the benthic communities. Here, we investigated meiofauna communities in the abyss at the scale of a prospective mining operation area. Random forest regressions were computed ...
DOI:
10.3390/d13010003