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Variable effects of marine-derived nutrients on algal production in salmon nursery lakes of Alaska during the past 300 years
marine-derived nutrients algal production salmon nursery lakes Alaska during the past 300 years
2014/4/22
We measured historical changes in sedimentary δ15N and fossil pigments in four lakes with anadromous semelparous salmon and two reference lakes to quantify the degree to which the flux of marine-deriv...
CO2 control of Trichodesmium N2 fixation, photosynthesis, growth rates, and elemental ratios: Implications for past, present, and future ocean biogeochemistry
CO2 control Trichodesmium N2 fixation photosynthesis growth rates elemental ratios past present future ocean biogeochemistry
2014/4/22
Diazotrophic marine cyanobacteria in the genus Trichodesmium contribute a large fraction of the new nitrogen entering the oligotrophic oceans, but little is known about how they respond to shifts in g...
American Association for the Advancement of Science Orbiter Provides New Hints of Past Groundwater Flows on Mars（图）
Groundwater
2007/2/27
15 February 2007，A spacecraft recently arrived at Mars has provided new evidence that fluids, likely including water, once flowed widely through underlying bedrock in a canyon that is part of the grea...
Spatial variability of stable isotopes and fossil pigments in surface sediments of Alaskan coastal lakes: Constraints on quantitative estimates of past salmon abundance
Spatial variability stable isotopes fossil pigments surface sediments Alaskan coastal lakes Constraints on quantitative estimates past salmon abundance
2014/5/4
We quantified spatial patterns of stable isotopes of N and C (δ15N, δ13C) and fossil pigment concentrations in the uppermost 10 mm of sediment (,10 yr) from 74 profundal locations and three spawning-s...
Past and present of sediment and carbon biogeochemical cycling models
Past present sediment carbon biogeochemical cycling models
2010/1/7
The global carbon cycle is part of the much more extensive sedimentary cycle that involves large masses of carbon in the Earth's inner and outer spheres. Studies of the carbon cycle generally followed...
Haunted by the past: Evidence for dormant stage banks of microparasites and epibionts of Daphnia
Haunted microparasites epibionts
2014/5/16
Microparasites and epibionts have important implications for the ecology and evolution of their zooplankton host
populations. Many parasites and epibionts produce resistant spores that infect new hos...
A Study on the Past and Present Diatom Flora of Two Alkaline Lakes
Lake Hafik Lake Tö dürge Diatom
2010/3/23
The diatom flora of Lakes Hafik and Tödürge was studied qualitatively. Each lake was sampled monthly during two periods. The first period was between April 1986 and June 1987 in Lake Hafik and be...
Use of a reduced-gravity model to evaluate present and past primary productivity in the tropical open ocean
a reduced-gravity model past primary productivity tropical open ocean
2014/6/10
Upwelling predicted by a reduced-gravity model is compared with remotely sensed primary productivity data through the tropical Atlantic and Pacific. The model upper layer thickness, an indicator of ve...