SPATIAL-DISTRIBUTION PATTERNS OF CRUSTACEA IN THE FLOODPLAIN AQUIFER OF AN ALLUVIAL RIVER

Citation
Jv. Ward et al., SPATIAL-DISTRIBUTION PATTERNS OF CRUSTACEA IN THE FLOODPLAIN AQUIFER OF AN ALLUVIAL RIVER, Hydrobiologia, 287(1), 1994, pp. 11-17
Citations number
10
Categorie Soggetti
Marine & Freshwater Biology
Journal title
ISSN journal
00188158
Volume
287
Issue
1
Year of publication
1994
Pages
11 - 17
Database
ISI
SICI code
0018-8158(1994)287:1<11:SPOCIT>2.0.ZU;2-#
Abstract
Interstitial crustaceans were collected from a grid of shallow samplin g wells penetrating the alluvial floodplain aquifer (ca. 10 m x 5 km x 10 km) of the Flathead River, Montana, USA. Eighteen taxa were identi fied, which collectively encompassed a range of hypogean-epigean affin ities. The subterranean amphipod Stygobromus spp., the most common cru stacean, occurred in all wells but was rare in the channel well. When well data were pooled into 'habitat types' (channel, bank, near-, cent ral-, and far-floodplain), distinct faunal patterns were apparent. Cru staceans constituted an increasing percentage of the total interstitia l fauna from the channel to the near-floodplain, then maintained simil ar relative abundance levels with increasing distance from the river. Stygobionts attained maximum values at near- and central-floodplain ha bitats where copepods and ostracods dropped to the lowest levels. Dist ribution and abundance patterns of Crustacea at the floodplain scale a re structured by hydrogeologic and geomorphic processes reflected only in part by distance from the river channel. The flood plain appears t o contain a latticework of alluvial-filled paleochannels of high hydra ulic conductivity that induce spatial discontinuities within the aquif er and that may play an important role in determining crustacean distr ibution patterns.