Comparing natural and planted black spruce seedlings. II. Nutrient uptake and efficiency of use
1993
Munson, A.D. | Bernier, P.Y.
The acclimation of planted black spruce (Picea mariana (Mill.) B.S.P.) seedlings to site nutrient condition was assessed by comparing their nutrient status with that of naturally regenerated seedlings on the same site during a 2-year period. The seasonal patterns for N, P, and K status (nutrient concentration and content) were markedly different for planted and natural seedlings. The former showed an early season decline in concentration that was less evident or absent in natural seedlings. This pattern persisted 1 year after planting, although biomass accumulation increased. Nutrient ratios indicated a strong culture regime effect on the balance of nutrients. This effect was considerably diluted 1 year after transplantation. Phosphorus and K levels in 1-year transplants and natural seedlings were close to the defined optimums for black spruce. Nutrient use efficiency of planted seedlings tended to increase with acclimation to site. Retranslocation from older needles of planted seedlings indicated net export of nutrients, while natural seedlings had a storage capacity in older foliage, indicated by net nutrient accumulation at the end of the growing season. Planting significantly reduced biomass allocation to current foliage, and naturally regenerated seedlings produced current foliage earlier in the growing season compared to planted seedlings.
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