This document discusses synthesizing and analyzing biodiversity in intermittent rivers. It notes that intermittent rivers are prevalent globally, not just in dry climates, and are expanding due to climate change. Intermittent rivers are dynamic ecosystems that are coupled to both aquatic and terrestrial habitats. The objectives of the IRBAS group are to assemble data on biodiversity and hydrology in intermittent rivers, analyze relationships between flow patterns and biodiversity, and translate knowledge into management practices. Key results so far show increased interest in intermittent rivers but fragmented existing knowledge, and that alpha diversity declines as flow intermittence increases. A global database on intermittent river biodiversity is being developed.

1. Synthesizing and analyzing biodiversity
in intermittent rivers
Thibault DATRY for IRBAS
Irstea Lyon
IRBAS group

2. IRs are prevalent
McMurdo Valley (Antarctica)
Tete (Mozambic)
Kapoeta (Sudan)
Rio Grande (USA)
Manganui (New Zealand)
Danube (Germany)
Rio Seco (Bolivia)

3. IRs are expanding
After Snelder et al. (HESS, 2013)
IRs are widespread globally,
not only in dry climates
IRs are expanding due to global
change

4. IRs are dynamic, coupled
aquatic-terrestrial
ecosystems
lotic
lentic
terrestrial
Habitats
Le Thouaret :
Datry et al., BioScience 2014

5. IRBAS objectives
① Assemble data on IR biodiversity and hydrology
② Estimate the abundance and distribution of IRs at
regional and continental scales
③ Analyze temporal trends in flow intermittence
④ Identify and quantify relationships between flow
intermittence, habitat dynamics, and structural and
functional biodiversity
⑤ Translate current knowledge into management practice

6. Key results
Increase in interest but fragmented
knowledge

7. Key results
As flow intermittence increases, alpha
diversity declines

8. Key results
More variation in alpha diversity is
explained by flow intermittence than other
flow regime components

9. Key results
Have increased awareness of scientists and
managers that IRs are numerically and
ecologically important
Developed guidelines for the management of
IRs, their hydrology and ecology

10. Key results
A global
database on IR
biodiversity

11. Perspectives
A H2020 European
network (>150
scientists) to continue
this synthesis effort for
the next 4 years
www.smires.eu