Rl. Wilby et al., FACTORS GOVERNING MACROPHYTE STATUS IN HAMPSHIRE CHALK STREAMS - IMPLICATIONS FOR CATCHMENT MANAGEMENT, Journal of the Chartered Institution of Water and Environmental Management, 12(3), 1998, pp. 179-187
Severe droughts in the late 1980s and 1990s have highlighted the fragi
lity of many aquatic environments in southern England; in particular,
declining river flows may be having an adverse affect on macrophytes i
n the chalk-fed streams of the Rivers Test and Itchen. Detailed macrop
hyte survey data which were collected from representative sites in bot
h rivers during 1991-1995 are interpreted in the contest of changing h
ydroclimatic, water quality and in-stream channel conditions. Multi-va
riate statistical analyses support the assertion that river flow is th
e most significant parameter governing observed changes in macrophyte
cover. During low flow years, filamentous algae have increased at most
sites to the detriment of Ranunculus spp. These findings have catchme
nt-management implications which should be addressed if the long-term
integrity of such aquatic ecosystems is to be safeguarded.