Effects of leaf duration, nutrient supply, and temperature on the seasonal pattern of growth and nitrogen uptake in tree seedlings in a subarctic environment
The seasonal dynamics of growth and nitrogen uptake were measured in pine (Pinus sylvestris) and birch (Betula pubescens ssp. tortuosa) seedlings growing in a subarctic environment. Whole-plant dry matter accumulated at about the same rate in both species. A higher rate of early summer assimilation...
| Published in: | Canadian Journal of Botany |
|---|---|
| Main Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Canadian Science Publishing
1989
|
| Subjects: | |
| Online Access: | http://dx.doi.org/10.1139/b89-029 http://www.nrcresearchpress.com/doi/pdf/10.1139/b89-029 |
| Summary: | The seasonal dynamics of growth and nitrogen uptake were measured in pine (Pinus sylvestris) and birch (Betula pubescens ssp. tortuosa) seedlings growing in a subarctic environment. Whole-plant dry matter accumulated at about the same rate in both species. A higher rate of early summer assimilation did occur in Pinus as revealed by the simultaneous increase in fine-root weight per unit length and leaf weight per unit area. Fine-root elongation and nitrogen uptake in Pinus preceded that in Betula. Seasonal variations in unit leaf rate and relative growth rate correlated with the prevailing temperature conditions. Pinus did not differ in phenology of growth with changes in nutrient supply while the growth and duration of foliage for Betula increased with increasing nutrient supply. Foliage growth in Pinus increased during spring but not in autumn. The temperature conditions during the growth period was important for determining the seasonal production of foliage in Betula. |
|---|