Biologic Markers of Air-Pollution Stress and Damage in Forests (1989) / Chapter Skim
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Nutrient-Use Efficiency as an Indicator of Stress Effects on Forest Trees
Nutrient-Use Efficiency as an Indicator of Stress Effects on Forest Trees
Pages 317-332
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From page 317... ...
Frequent tissue or solution nevertheless lead to a reliable basis for interpreting on trees, but this approach requires intimate the diurnal, wetting and drying, and annual cycles of The ratio of dry weight gain to net nutrient uptake is one definition of nutrientuse efficiency (NUE)
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From page 318... ...
A hypothesized natural progression with increasing stand age is indicated by -- where canopy closure occurs at point T _ uptake)
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From page 319... ...
Light-saturated net photosynthesis rates of leaves of Eucalyptus species with differing nitrogen concentration. Source: Reprinted with permission of Springer-Verlag N.Y., Inc.
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From page 320... ...
In a scenario of increasing ozone exposure and nitrogen deposition, a significant shift from the nonstressed relationship between leaf photosynthesis and leaf nitrogen concentration may occur.
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From page 321... ...
Again, this value applied to a wide range of natural stress conditions suggesting that the aboveground response of NUE to stress follows the trajectory Tb of Fig.
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From page 322... ...
Relationship of N-use efficiency to N status of birch (Betula verrucosa) seedlings.
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From page 323... ...
Uptake of nitrogen and phosphorus into aboveground components as a function of net primary production (NPP) using data reported for coniferous forests from boreal )
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From page 324... ...
Interpretation of the results as NUE, however, is problematic due to phenological controls on growth, utilization of internal carbon and nutrient storages, remobilization of nutrients, and the seasonality of nutrient uptake (van den Driessche l 984~. Utilization of carbon and nutrient storage in springtime foliar growth is initially "negative growth" because respiration exceeds carbon gain.
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From page 325... ...
It is difficult to identify a time frame within the annual cycle in which measurement of AC/AN can provide an unambiguous NUE indicator of plant response to stress. Alternatively useful indicators based on carbon and nutrient dynamics may come from consideration of these components in a whole-plant physiological framework that is less constrained than the NUE concept.
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From page 326... ...
Steady-state dependence of plant starch concentration (ma starch g-1 dry weight) on plant nitrogen concentration (ma N g- 1 dry weight)
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From page 327... ...
Relationship between starch and nitrogen concentrations in loblolly pine needles in control (open symbols) and fertilized (solid symbols)
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From page 328... ...
noted that the relative demands made by forests for soil minerals decrease markedly after canopy closure; trees increasingly depend on internal retranslocation to meet nutrient requirements for annual growth. Nitrogen retranslocation in a pine plantation was calculated to increase from 11 to 69 kg ha~1 year~1 with increase in age from 10 to 40 years.
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From page 329... ...
SUMMARY NUE determined on annual time steps seems to be an insensitive indicator of stress since changes in carbon gain and nutrient uptake tend to occur in the same direction. Determination of NUE within a growing period is complicated by deterministic controls on growth, internal storage and retranslocation, and allocation to root processes.
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From page 330... ...
1985. Ambient levels of ozone reduce net photosynthesis in tree and crop species.
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From page 331... ...
4:204-246. Nitrogen metabolism, translocation, and recycling in van den Driessche, R
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