Stream Sampling Framework and Application for Frequency Cap Statistics

Five commercially available carbon dioxide analysers were assessed with respect to accuracy, response time, stability, the effect of water vapour and the effect of rebreathing. Two side-stream sampling analysers (Datex Normocap and Engstrom Eliza) and one main-stream sampling analyser (Hewlett-Packard Capnoshot) were found to be satisfactory for use both in the operating theatre and intensive care unit. The Instrumentation Laboratory (IL) 200, a side-stream monitor, performed satisfactorily but neither it nor the Siemens Sirecust 404, a main-stream monitor, has the facility to compensate for the presence of nitrous oxide. The Siemens analyser, in the form tested, could not be recommended for clinical use, as it was less accurate than the other monitors, could not detect rebreathing, and was subject to fluctuations when used with gas mixtures saturated with water vapour.

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Disease on Nursery Stock as Affected by Environmental Factors and Seasonal Inoculum Levels of Phytophthora ramorum in Stream Water Used for Irrigation

Plant Disease ◽

10.1094/pdis-92-11-1566 ◽

2008 ◽

Vol 92 (11) ◽

pp. 1566-1573 ◽

Cited By ~ 26

Author(s):

S. A. Tjosvold ◽

D. L. Chambers ◽

S. T. Koike ◽

S. R. Mori

Keyword(s):

Stream Water ◽

Disease Incidence ◽

Phytophthora Ramorum ◽

Sudden Oak Death ◽

Nursery Stock ◽

Stream Sampling ◽

Flow Through ◽

High Concentrations ◽

Electronic Sensors ◽

Native Host

A pear bait monitoring system was used to detect and quantify Phytophthora ramorum propagules in streams that flow through woodland areas with sudden oak death in Santa Cruz County, CA from 2001 to 2007. Stream propagules were detected most frequently or occurred in highest concentrations in winter and spring. The stream propagule concentration was characterized with statistical models using temperature and rainfall variables from 2004 to 2007. The highest concentrations of propagules occurred when stream sampling was preceded by about 2 months with low maximum daily temperatures and by 4 days with high rainfall. The occurrence of propagules in streams in the summer was mostly associated with infected leaves from the native host Umbellaria californica that prematurely abscised and fell into the water. When the stream water was used for irrigating rhododendron nursery stock from 2004 to 2007, disease occurred only three times in the two wettest springs (2005 and 2006) on plants sprinkler irrigated with stream water with relatively high concentrations of propagules. Disease incidence was described with a statistical model using the concentration of infective propagules as measured by pear baiting and consecutive hours of leaf wetness measured by electronic sensors at rhododendron height. The concentration of infective propagules was significantly reduced after water was pumped from the stream and applied through sprinklers.

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Effectiveness of stream sampling methods in capturing non-native Rusty Crayfish (Orconectes rusticus) in Ontario

The Canadian Field-Naturalist ◽

10.22621/cfn.v128i2.1564 ◽

2014 ◽

Vol 128 (2) ◽

pp. 111 ◽

Cited By ~ 3

Author(s):

Scott M. Reid ◽

Jane Devlin

Keyword(s):

Sampling Methods ◽

Capture Probability ◽

Sexually Active ◽

Orconectes Rusticus ◽

Rusty Crayfish ◽

Stream Sampling ◽

First Pass ◽

Native Crayfish ◽

Removal Model ◽

Species Removal

Habitat alteration and species introductions have contributed to the decline of native crayfish in Ontario. although lake populations of crayfish in Ontario are monitored, there is no corresponding program for streams. We used removal-based sampling to evaluate the efficacy of three sampling techniques (backpack electrofishing, hand capture, and seining) to characterize native and non-native crayfish populations in six streams in the Kawartha lakes region and five streams in the Muskoka/Haliburton lakes region. all types were effective at detecting non-native Rusty Crayfish (Orconectes rusticus). Rusty Crayfish were collected from 65% of samples, constituted 90% of the total catch, and were the only species present in 30% of streams. Compared with other methods, electrofishing was more likely to capture additional crayfish species. Removal-based sampling was not a reliable approach for estimating capture probability and population size. Failure of the removal model was due to increases in the number of crayfish captured after the first pass or too few individuals collected. Mean capture probabilities for electrofishing (0.30) and hand capture (0.31) did not result in reliable population estimates. Compared with seining, electrofishing and hand capture resulted in more sexually active males (fewer sexually inactive males) and more small (< 25 mm carapace length) individuals. For each method, there were differences in capture probability among length classes. a combination of electrofishing and seining (with multiple passes) would maximize species detection, permit sampling of a range of habitat types, and be easily integrated into existing stream fish surveys.

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