Results
601 - 625 of 657 Items << < 20 21 22 23 24 25 26 27 > >>
601 - 625 of 657 Items << < 20 21 22 23 24 25 26 27 > >>
|
The diurnal vertical movement of zooplankton was first recorded in freshwater lakes by Weismann (1877) in Lake Constance (Bodensee), although Cuvier was credited with observing the migration of Daphniae in 1817 (Gushing, 1955). The migration is...
1974-01-01
|
|
The survey results indicate that the impoundment of water behind Hoover Dam has not adversely affected the dissolved oxygen (DO) content and that water quality and DO content were uniform regardless of depth. The study made in April-May 1964 will...
1965-06-01
|
|
Lake Mead has undergone a serious decline since Glen Canyon Dam was constructed 450 km upstream in 1963.
State fisheries management agencies are concerned that the decline was caused by water level fluctuations and more severe drawdowns during the...
1981-06-01
|
|
Although the Great Salt Lake is frequently treated as if it were a single body of water, the natural bays and transportation causeways have divided it into a system of four bays. The bays, however, do not function independently because water,...
2006-01-01
|
|
Historically, thousands of Snake River Sockeye salmon returned to the Sawtooth Valley to spawn. Evermann (1896) reported that the Sawtooth Valley Lakes were teeming with red fish. Bjornn (196~) estimated that 4,360 sockeye returned to Redfish Lake...
1993-01-01
|
|
Physical characteristics of lakes are highly interrelated with biological characteristics. We measured and analyzed the physical characteristics of two side canyons in order to better understand differences in productivity between side canyons and...
1997-01-01
|
|
Between 26 April and 2 May 1992, students in a utah state university aquatic ecology class visited Lake Powell to do a study of trophic gradients of the reservoir. The main axis of the reservoir was surveyed, as well as less detailed analyses of...
1992-01-01
|
|
1.The objective was to identify the factors driving spatial and temporal variation in annual production (PA) and turnover (production/biomass) ratio (P/BA) of resident brown trout Salmo trutta in tributaries of the Rio Esva (Cantabrian Mountains,...
2011-01-01
|
|
Most subspecies of cutthroat trout Oncorhynchus clarkii are imperiled or extinct due to the combined effects of habitat degradation and interactions with exotic species. To quantify abundance and vital rates and evaluate trends, we selected a...
2007-01-01
|
|
We counted kokanee spawners and carcasses every 1-7 days from mid-September through mid-November in 1991 and 1992 in Taylor Creek, a tributary to Lake Tahoe, California-Nevada. Less than 1% of the spawning run entered Taylor Creek before flow from...
1994-01-01
|
|
New technologies are emerging that enable researchers to measure physical environments and habitats at increasingly fine scales and over wide extents. Measurement of physical conditions at fine scales contributes to the understanding of how...
2011-01-01
|
