Rock snot and lake mud: exploring the history of recent blooms of didymosphenia geminata using information contained in lake sediments

Ecosystem managers have often considered the nuisance diatom species, Didymosphenia gemi¬nata (didymo) as being introduced to the natural environment through human activities; however, observations from early 20th-century surveys challenge this characterization. We use diatoms pre¬served in lake sediment cores to investigate the history of didymo blooms from Gaspésie, Quebec. Relative abundances of diatoms were examined from the dated sediments of Lac Humqui and Lac au Saumon (a lake with an inflowing river currently supporting blooms). Didymo was observed throughout the Lac au Saumon core, demonstrating that it has been present in the region well before the first reports of blooms in 2006. Lac Humqui diatom assemblages experienced a shift in composition with declines in benthic taxa (attached to substrates) and increases in planktonic (free floating) diatoms that began ~1970. Strong relationships between this diatom shift, and increases in regional air temperatures and earlier river ice-out dates were consistent with the expected effects of climate warming on aquatic systems. Our paleolimnological evidence shows that climate warming, rather than human introduction, likely plays an important role in triggering didymo blooms

(J. Human Lactation, 15:113-120)Content of lipid nutritients in the milk of Fulani women

International audienceSpits are present all along the Channel and Atlantic coasts of France. They belong to different types, depending on their composition and genesis. Some of them were initiated when RSL stabilized about its present level, 2,500 years ago. Many others are much more recent and were created when major land-use changes took place in mainland watersheds. Soil erosion increased the fluvial sediment supply and many river mouths were stabilized. All these spits continue to evolve under variable degrees of human control (mainly on sediment delivery). This paper present three examples (Arçay, Talbert, Cayeux) which illustrate the main types of issues faced by coastal planners dealing with spits in western France