Biotic Indices and Stream Ecosystem Processes: Results from an Experimental Study

1996 ◽  
Vol 6 (1) ◽  
pp. 140-151 ◽  
Author(s):  
J. Bruce Wallace ◽  
Jack W. Grubaugh ◽  
Matt R. Whiles
Keyword(s):  
Experimental Study ◽  
Ecosystem Processes ◽  
Biotic Indices ◽  
Stream Ecosystem

Recent land-use changes affect stream ecosystem processes in a subtropical island in Brazil

2020 ◽  
Vol 45 (5) ◽  
pp. 644-658
Author(s):  
Aurea Luiza Lemes da Silva ◽  
William Padilha Lemes ◽  
Jéssica Andriotti ◽  
Mauricio Mello Petrucio ◽  
Maria João Feio
Keyword(s):  
Land Use ◽  
Land Use Changes ◽  
Ecosystem Processes ◽  
Stream Ecosystem

Understanding effects of small dams on benthic metabolism and primary production in temperate forested streams

2020 ◽  
Vol 193 (3) ◽  
pp. 227-237
Author(s):  
John P. Ludlam ◽  
Allison H. Roy
Keyword(s):  
Nutrient Limitation ◽  
Ecosystem Processes ◽  
Nutrient Concentrations ◽  
Ecosystem Responses ◽  
Stream Ecosystem ◽  
Benthic Metabolism ◽  
Factors Associated ◽  
Physical Conditions ◽  
And Control ◽  
Func Tion

Dams can alter the chemical and physical conditions of downstream environments by increasing stream temperatures, altering nutrient limitation, reducing flow variability, and reducing fine sediment deposition. However, little is known about how fundamental stream ecosystem processes like productivity and respiration respond to dams. Nutrient diffusing substrates were installed in three dam streams and three control streams to evaluate the effect of dams on benthic gross primary productivity (GPP), respiration (R), and chlorophyll α production. Dam streams were an average of 5.6 °C warmer than control streams but GPP, R and chlorophyll α were not different between control and dam streams. Phosphorus enrichment increased heterotrophic R relative to controls (~1.8×) but not autotrophic GPP, R or chlorophyll α. Stream nutrient concentrations and nutrient limitation of heterotrophic R were similar in dam and control streams, suggesting that the dams had limited effects on nutrient transport downstream. Autotrophic GPP, R and chlorophyll α were limited by light and varied within and across streams, potentially masking our ability to detect differences caused solely by dams. Dams may alter stream ecosystem func- tion but consideration of other factors associated with and independent of dams is critical for predicting ecosystem responses to dams.

scholarly journals Trophic Tangles through Time? Opposing Direct and Indirect Effects of an Invasive Omnivore on Stream Ecosystem Processes

PLoS ONE ◽  
2012 ◽  
Vol 7 (11) ◽  
pp. e50687 ◽  
Author(s):  
Jonathan W. Moore ◽  
Stephanie M. Carlson ◽  
Laura A. Twardochleb ◽  
Jason L. Hwan ◽  
Justin M. Fox ◽  
...  
Keyword(s):  
Indirect Effects ◽  
Ecosystem Processes ◽  
Direct And Indirect Effects ◽  
Stream Ecosystem

Forest Age Influences In-stream Ecosystem Processes in Northeastern US

Ecosystems ◽  
2016 ◽  
Vol 20 (5) ◽  
pp. 1058-1071 ◽  
Author(s):  
H. A. Bechtold ◽  
E. J. Rosi ◽  
D. R. Warren ◽  
W. S. Keeton
Keyword(s):  
Ecosystem Processes ◽  
Forest Age ◽  
Stream Ecosystem

Experimental study on the restoration from a tilt-azimuth series for improvement in resolution

1995 ◽  
Vol 53 ◽  
pp. 636-637
Author(s):  
Norio Baba ◽  
Norihiko Ichise ◽  
Syunya Watanabe
Keyword(s):  
Experimental Study ◽  
Spherical Aberration ◽  
Incident Beam ◽  
Optical Parameters ◽  
Beam Tilting ◽  
Illumination Method ◽  
Restoration Method ◽  
Illumination Mode

The tilted beam illumination method is used to improve the resolution comparing with the axial illumination mode. Using this advantage, a restoration method of several tilted beam images covering the full azimuthal range was proposed by Saxton, and experimentally examined. To make this technique more reliable it seems that some practical problems still remain. In this report the restoration was attempted and the problems were considered. In our study, four problems were pointed out for the experiment of the restoration. (1) Accurate beam tilt adjustment to fit the incident beam to the coma-free axis for the symmetrical beam tilting over the full azimuthal range. (2) Accurate measurements of the optical parameters which are necessary to design the restoration filter. Even if the spherical aberration coefficient Cs is known with accuracy and the axial astigmatism is sufficiently compensated, at least the defocus value must be measured. (3) Accurate alignment of the tilt-azimuth series images.

An Experimental Study of Some Properties of Stuttered Words

1962 ◽  
Vol 5 (4) ◽  
pp. 387-394 ◽  
Author(s):  
Bruce Quarrington ◽  
Jerome Conway ◽  
Nathan Siegel
Keyword(s):  
Experimental Study
Sign in / Sign up

Export Citation Format

Share Document