Figure 4: Observed feedback at the population level. (a)
Established dense pioneer black poplar cohort with a very high growth
rate on a gravel bar of the Garonne River; (b) same cohort in winter,
with well-distinguishable massive sediment trapping in the vegetation
unit. Photographs: Dov Corenblit.
Community-level feedbacks: responses and effects of
biodiversity on the functioning of riverine ecosystems
At the community level, riparian vegetation can decisively modulate
fluvial dynamics, and in return, adjusts its structure (floristic
composition, physiognomy and mean trait value) to new environmental
configurations evolving under biotic control according to characteristic
resilient succession patterns. Research carried out on the Tech and
Allier Rivers permitted to identify, at the community level, a number of
key elements of the abiotic-biotic feedback which control the structure
and functioning of riverine ecosystems in different and more or less
artificialized hydrogeomorphological contexts. As suggested by Tilman
(1996), Loreau et al. (2001; 2021) and Hooper et al. (2005), our
investigations showed that the diversity of response and effect traits
of engineer organisms influences the functioning and stability or
resilience of the ecosystem (Fig. 5).