Measured 37-yr changes in soil N at primary succession sites at Glacier Bay, Alaska, differ from changes inferred from a chronosequence of sites
Fastie CL. 1993. Measured 37-yr changes in soil N at primary succession sites at Glacier Bay, Alaska, differ from changes inferred from a chronosequence of sites. Bulletin of the Ecological Society of America. 74(2):231
To verify the pattern of change in soil N pools inferred by Crocker and Major (1955) from the classic 200 yr chronosequence of primary succession sites at Glacier Bay, Alaska, I resampled five of their original sites in 1989. Directly measured 37-yr changes at sites < 100 yr old are not different from changes inferred from the chronosequence. However, a 140 yr old site expected to have declined to the levels of older sites near 200 g N/m2 instead increased from 275 g N/ m2 to 347 +/- 12 g N/m2 between 1952 and 1989. This is consistent with dendroecological stand reconstructions indicating that the early successional history of sites older than 140 yr did not include long-lived thickets of N-fixing Sitka alder (Alnus sinuata) which are characteristic of all younger sites. The presence of multiple successional pathways at Glacier Bay makes uncritical inference from this chronosequence unwarranted.
- Type
- Journal Article
- Authors
- Fastie, Christopher
- Units
- GLBA
- Keywords
- Management, Natural Resource, Nutrients, Soil Science