ISSN:
1573-5117
Keywords:
leaf processing
;
decomposition
;
leaf bags
;
environmental impact
;
stream ecology
;
disturbance
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Rates of leaf litter processing at eight sites were used in conjunction with other methods to evaluate the impact of highway construction on aquatic habitats. Monthly processing of white oak leaves from four different mesh size bags at unimpacted reference sites indicated that the three larger mesh sizes were useful for comparing sites, as they did not restrict invertebrate colonization and provided similar rates of processing within sites. Small mesh size (0.12 mm) prevented leaf shredding macroinvertebrates from colonizing bags, and caused significantly slower leaf processing in a riffle. Leaf processing was fastest in a reference riffle above an area of highway construction but was significantly slower in the reference pool due to low current velocity and the absence of shredders. Leaf processing in a riffle below the highway was slower than the reference riffle, and the number of shredders was reduced. Removal of streamside vegetation during highway construction caused increased stream temperatures and reduced the amount of natural leaf accumulations, thereby reducing shredder habitat. At other sites highway construction caused less of an impact than preexisting environmental influences. Leaf processing in an riffle of a lower pH stream was significantly slower than in the reference riffle. Shredders were absent from the low pH stream, and rates of leaf processing in the acid impacted riffle and pool were similar to those of the reference pool. Comparisons of the low pH stream with the reference stream indicated that physical processes were less important than biological processes of leaf decay. Leaf processing in ponds was similar to that of stream pools. Processing was faster in a small versus large pond, and a high density of invertebrates was associated with leaf bags in the small pond after one year.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00006030
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