1000 resultados para subtropical lake


Relevância:

20.00% 20.00%

Publicador:

Resumo:

EXTRACT (SEE PDF FOR FULL ABSTRACT): Sediment traps placed in the profundal region of Elk Lake, north central Minnesota during the 1979 spring and 1983-84 fall and spring seasons monitored seasonal diatom production for two climatically distinctive periods.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Lake sturgeon Acipenser fulvescens restoration is a priority throughout the Great Lakes basin, where sturgeon have been reduced to less than 1% of historic levels due to habitat degradation, overharvest, and fragmentation of spawning populations. The population parameters most important to long-term lake sturgeon persistence are unknown.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The distribution and intensity of a bloom of the toxic cyanobacterium, Microcystis aeruginosa, in western Lake Erie was characterized using a combination of satellite ocean-color imagery, field data, and meteorological observations. The bloom was first identified by satellite on 14 August 2008 and persisted for more than 2 months. The distribution and intensity of the bloom was estimated using a satellite algorithm that is sensitive to near-surface concentrations of M. aeruginosa. Increases in both area and intensity were most pronounced for wind stress less than 0.05 Pa. Area increased while intensity did not change for wind stresses of 0.05–0.1 Pa, and both decreased for wind stress greater than 0.1 Pa. The recovery in intensity at the surface after strong wind events indicated that high wind stress mixed the bloom through the water column and that it returned to the surface once mixing stopped. This interaction is consistent with the understanding of the buoyancy of these blooms. Cloud cover (reduced light) may have a weak influence on intensity during calm conditions. While water temperature remained greater than 15°C, the bloom intensified if there were calm conditions. For water temperature less than 15°C, the bloom subsided under similar conditions. As a result, wind stress needs to be considered when interpreting satellite imagery of these blooms.