Quantifying Differences in Responses of Aquatic Insects to Trace Metal Exposure in Field Studies and Short-Term Stream Mesocosm Experiments

We investigated the effects of Velpar L (hexazinone) on ectomycorrhizal (Laccarialaccata) and nonmycorrhizal Pinusresinosa seedlings in the greenhouse and in the field. In both greenhouse and field studies, seedling growth was reduced by Velpar L at 1, 2, and 4 kg/ha application rates in the short term (2 months' exposure) with significant recovery occurring afterwards. Seedling mortality occurred only with herbicide treatments and was higher in the greenhouse than in the field. The 4 kg/ha Velpar L treatment caused the highest mortality and toxicity was most pronounced in the mycorrhizal (Laccarialaccata inoculated) seedlings. In both experiments mycorrhizal infection was significantly reduced by 2 and 4 kg/ha Velpar L treatments during the 0- to 2-month and 2- to 6-month exposure periods, with significant recovery occurring in the latter. Although seedlings not infected with Laccarialaccata became mycorrhizal through unidentified indigenous species, their infection rates were also affected by Velpar L at all levels during the 0- to 2-month period and at the 2 and 4 kg/ha levels after 2–6 months of exposure to the herbicide.

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The mark–recapture method applied to population estimates of a freshwater crab on an alluvial plain

Marine and Freshwater Research ◽

10.1071/mf12350 ◽

2013 ◽

Vol 64 (4) ◽

pp. 317 ◽

Cited By ~ 3

Author(s):

Débora de Azevedo Carvalho ◽

Pablo Agustín Collins ◽

Cristian Javier De Bonis

Keyword(s):

Hydrological Cycle ◽

Field Studies ◽

Accurate Method ◽

Alluvial Plain ◽

Short Term ◽

Chi Square ◽

Mark Recapture ◽

Closed Population ◽

Short Term Study ◽

Chi Square Test

Mark–recapture methods are a useful population estimation tool, although with many assumptions that cannot always be satisfied for all types of organisms and environments. In the present study, three mark–recapture methods (Petersen, Schnabel and Schumacher–Eschmeyer) were applied in a preliminary trial to estimate the population size of the crab Trichodactylus borellianus and to gain information that would support the use of the methods in the field. The accuracy of these estimates was verified by analysing the percentage of bias, the width of the confidence intervals, and by a chi-square test. The assumptions of equal catchability and closed population were verified, along with assumptions related to the efficiency of marking. The adjusted methodology was applied in a short-term study of a pond on the Paraná floodplain. The results showed that the assumptions were satisfied for both the experimental and field studies. The Schnabel was the most accurate method evaluated in both studies. Although the Schumacher–Eschmeyer method also provided accurate results in the field study, it needed large samples to give reliable estimates. The applicability of these methods depends on the stage of the hydrological cycle. The choice of a short-term research design will ensure that the assumption of a closed population is valid for research of this type on an alluvial plain.

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Predicting Trace Metal Exposure in Aquatic Ecosystems: Evaluating DGT as a Biomonitoring Tool

Exposure and Health ◽

10.1007/s12403-018-0280-3 ◽

2018 ◽

Vol 12 (1) ◽

pp. 19-31 ◽

Cited By ~ 4

Author(s):

Carlos Eduardo Eismann ◽

Amauri Antonio Menegário ◽

Hendryk Gemeiner ◽

Paul Nicholas Williams

Keyword(s):

Trace Metal ◽

Aquatic Ecosystems ◽

Metal Exposure ◽

Biomonitoring Tool

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Effect of Short-Term Metal Exposure on Epididymal Antioxidant Status and Sperm Parameters and the Protective Role of Melatonin.

Biology of Reproduction ◽

10.1093/biolreprod/81.s1.648 ◽

2009 ◽

Vol 81 (Suppl_1) ◽

pp. 648-648

Author(s):

Niraj R. Joshi ◽

Sudip Banerjee ◽

Raktim Mukherjee ◽

Shail Chaube ◽

A.V. Ramachandran

Keyword(s):

Antioxidant Status ◽

Protective Role ◽

Sperm Parameters ◽

Metal Exposure ◽

Short Term

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Short- and Long-Term Effects of Nonconsciously Processed Ambient Scents in a Servicescape: Findings From Two Field Experiments

Journal of Service Research ◽

10.1177/1094670519842333 ◽

2019 ◽

Vol 22 (4) ◽

pp. 440-455 ◽

Cited By ~ 6

Author(s):

Anna Girard ◽

Marcel Lichters ◽

Marko Sarstedt ◽

Dipayan Biswas

Keyword(s):

Large Scale ◽

Field Experiments ◽

Field Studies ◽

Long Term Effects ◽

Short Term ◽

Railway Company ◽

Short And Long Term ◽

Ambient Scents ◽

Short Term Effects

Ambient scents are being increasingly used in different service environments. While there is emerging research on the effects of scents, almost nothing is known about the long-term effects of consumers’ repeated exposure to ambient scents in a service environment as prior studies on ambient scents have been lab or field studies examining short-term effects of scent exposure only. Addressing this limitation, we examine the short- and long-term effects of ambient scents. Specifically, we present a conceptual framework for the short- and long-term effects of nonconsciously processed ambient scent in olfactory-rich servicescapes. We empirically test this framework with the help of two large-scale field experiments, conducted in collaboration with a major German railway company, in which consumers were exposed to a pleasant, nonconsciously processed scent. The first experiment demonstrates ambient scent’s positive short-term effects on consumers’ service perceptions. The second experiment—a longitudinal study conducted over a 4-month period—examines scent’s long-term effects on consumers’ reactions and demonstrates that the effects persist even when the scent has been removed from the servicescape.

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Field Evaluation of Late Merge Traffic Control in Work Zones

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198105191100104 ◽

2005 ◽

Vol 1911 (1) ◽

pp. 33-41 ◽

Cited By ~ 3

Author(s):

Andrew G. Beacher ◽

Michael D. Fontaine ◽

Nicholas J. Garber

Keyword(s):

Field Test ◽

Traffic Control ◽

Positive Response ◽

Field Evaluation ◽

Field Studies ◽

Work Zone ◽

Work Zones ◽

Short Term ◽

Term Field ◽

Lane Closures

The traffic control strategy of the late merge in work zones was devised to improve flow and safety at work zone lane closures. Although some states have put the strategy into practice, only a handful of short-term field studies have formally evaluated its effectiveness. Additional field studies were necessary to assess the efficacy of the strategy and its proper deployment. This paper documents the results of a field test of the late merge traffic control conducted over several months. The late merge strategy was evaluated by comparing its effectiveness with that of traditional plans for work zone lane closures. The field test was conducted on a primary route in Tappahannock, Virginia, at a two-to-one lane closure. Results showed that throughput increased, but the increase was not statistically significant. Likewise, time in queue decreased, but the decrease was not statistically significant. These results were much less dramatic than those of other studies. Possible reasons for this disparity include different driver populations, road types, vehicle mixes, and site-specific characteristics. Despite limited improvements in throughput and time in queue, more drivers were in the closed lane, a positive response to the late merge signs.

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