11 February 2007
Ammonia: a candidate for nitrogen transfer
In mycorrhizal associations, the fungal partner assists its plant host with nitrogen and phosphorus uptake while obtaining photosynthetically fixed carbon. Recent studies in mycorrhiza have highlighted the potential for direct transfer of ammonia from fungal to plant cells. This presents a new perspective on nitrogen transfer at the mycorrhizal interface, which is discussed here in light of recent progress made in characterizing a large array of membrane proteins that could fulfil the function of transporting ammonia.
16 December 2006
transect points: Invasive Earthworms
Research shows that invasive earthworms are damaging forest soils and are a menace to species diversity. The problem is most often associated with formerly glaciated regions, where native populations of earthworms are not present. Comparing soil in front of the invaders to post invasion conditions demonstrates that these worms cause soil compaction, reduced soil fertility, and increased erosion. It appears that these invaders are capable of alterations deep enough into the soil profile to result in a change in soil taxonomic classification at the order level. Other concerns are damage to rhizosphere functions, impairing soil carbon sequestration capacity.
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