ISSN:
1432-1009
Keywords:
Watersheds
;
Budgets
;
Nitrogen
;
Phosphorus
;
Channelization
;
Swamps
;
Floodplain
Source:
Springer Online Journal Archives 1860-2000
Topics:
Energy, Environment Protection, Nuclear Power Engineering
Notes:
Abstract Nitrogen and phosphorus exports from channelizedstream watersheds were elevated over those from nearby natural swamp-stream watersheds. Nitrate exports were significantly greater from channelized-stream watersheds, and higher exports were attributed to faster groundwater drawdown, continual streamflow, and transformation of former floodplain to croplands following channelization. Exports of total organic nitrogen and total nitrogen were also significantly greater from channelized-stream watersheds. Differences in the exports of ammonium, filterable reactive phosphorus, and filterable unreactive phosphorus between the two watershed types were not detectable. Particulate phosphorus exports were significantly higher from channelized-stream watersheds, presumably because of greater erosion potential of nearby croplands and steep channel banks in the altered watersheds. The presence of nonpoint sources of pollution increased watershed exports of nutrients regardless of stream morphology. Examination of nutrient budgets for a portion of swamp floodplain at the base of one natural-stream watershed revealed that changes in local groundwater hydrology and stream morphology associated with channelization appeared to have greater effect on nutrient exports than simply the loss of bordering forested floodplain.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01866936
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