|
|
||||||||
ABSTRACT
High-elevation forests receive large amounts of atmospheric lead (Pb) and accumulate it in the forest floor. In order to determine Pb partitioning in a montane, coniferous forest, we analyzed forest floor and mineral soil (Haplorthods and Fragiorthods), and vegetation parts (leaves, twigs, bark, wood) for their Pb content. Soil and stream water were sampled to estimate Pb flux. Mean Pb concentration in trees, in mg kg–1, was root bark (33.0), twigs (28.3), bark (23.0) > root wood (10.4) > foliage (3). wood (3). Total Pb in above-ground biomass (trees + shrubs + herbs) was 0.89 kg ha–1. Lead in the organic horizon (forest floor) was 20 kg ha–1 while Pb in the mineral horizon (E + B) was 63 kg ha–1.
Monitoring of soil water for one year yielded volume-weighted mean Pb concentrations of 3.7, 1.8, 1.1, and 1.0 µg L–1 at 3-, 12-, 25-, and 40-cm depth, respectively. Stream Pb concentration averaged 0.6 µg L–1. We estimated annual Pb input of > 700 g ha–1 yr–1. Estimated output from the forest in stream water was < 12 g ha–1 yr–1. Annual accumulation in the forest floor is approximately 3% of the current forest floor Pb amount. At current accumulation rates, forest floor Pb amount will double in 30 to 40 yr. At current leaching rates, mean residence time of Pb in the forest floor is approximately 500 yr. The ratio of Pb input to output for the forest is 60:1.
Key Words: biogeochemistry lysimeter forest soils air pollution
1 Contribution from the Dep. of Geology/D4, Univ. of Pennsylvania, Philadelphia. This project was funded by a grant from the Andrew W. Mellon Foundation and a Grant-In-Aid of Research from the Sigma Xi Society to the senior author.
2 Research associate (formerly graduate assistant) and associate professor, respectively, Univ. of Pennsylvania, Philadephia, PA 19104.
Received for publication January 9, 1985.
This article has been cited by other articles:
![]() |
R. D. Yanai, D. G. Ray, and T. G. Siccama Lead Reduction and Redistribution in the Forest Floor in New Hampshire Northern Hardwoods J. Environ. Qual., January 1, 2004; 33(1): 141 - 148. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Vadose Zone Journal | Journal of Plant Registrations | ||||
| Journal of Natural Resources and Life Sciences Education |
Soil Science Society of America Journal |