Spruce needles

Although seen only occasional during the first half of this century, winter injury of first-year red spruce needles has become an annual event in the coniferous montane forest area, resulting in the formation of red-brown first year needles that subsequently desiccate and are shed 20, 21). The loss of foliage reduces photosynthesis and the obligatory accumulation of carbohydrate in the twigs and root systems. There is some evidence that this phenomenon involves both natural and anthropogenic causal factors. 

Figure 9. Exposure pathways based on the averaged coefficients ofbiogeochemical uptake, Cb, of trace metals in Spruce Forest ecosystems of the Karelia top scheme represents the ecosystem with Podzols on diabase outcrops and bottom scheme represents the ecosystem with Podzols on gneiss outcrops. 1—spruce needles 2—spruce bark 3—hypnic mosses 4—leaves and twigs of blueberry (based on Dobrovolsky, 1994).

Ruhling, A., and G. Tyler. Effects of Heavy Metal Pollution on the Decomposition of Spruce Needle Litter. Department of Plant Ecology, University of Lund, Sweden, 1972. 48 pp. 

Strack, D. et al.. Structures and accumulation patterns of soluble and insoluble phenolics from Norway spruce needles. Phytochemistry, 28, 2071, 1989. 

In addition to the damage acid rain causes to structures, acid rain also affects natural environments. Significant loss of spruce forests due to the burning of spruce needles by acid rain has occurred in Scandinavia. Acid rain also extracts a heavy toll on aquatic systems and associated organisms. Most adult fish cannot tolerate pHs much lower than 5.0, and even the most tolerant species will not survive below a pH of 4.0. Fish larvae are even more susceptible to low pH levels. Insects and their larvae also perish when pH approaches 4.0 in aquatic systems. Numerous lakes in upstate New... 

Oberg G, Nordlund E, Berg B (1996) In situ Formation of Organically Bound Halogens During Decomposition of Norway Spruce Needles Effects of Fertilization. Can J For Res 26 1040... 

Current plant-air partitioning data are limited to a very few species, namely azalea leaves and rye grass and a few data for spruce needles. The plant-water partitioning data used to develop methods also are limited to isolated cuticles from just four plants and macerated barley leaves. We thus cannot expect that currently available methods adequately account for the interspecies variability in partitioning. 

Frank, H. and W. Frank. 1989. Uptake of Airborne Tetrachloroethene by Spruce Needles. Environ. Sci. Technol. 23, 365-367. 

Photolysis t,/2 = 81.5 h on spruce needle surfaces under sunlight irradiation (Niu et al. 2003). 

Photolysis photolytic degradation t,/2 = 3.5 h of PCDD in extract of fly-ash in tetradecane solution for native congener and t/2 = 3.1 h for 13C-labelled congener (Tysklind Rappe 1991) t1/2 = 55.0 h on spruce needle surfaces under sunlight irradiation (Niu et al. 2003)... 

Riss A, Hagenmaier H, Weberruss U, et al. 1990. Comparison of PCDD/PCDF levels in soil, grass, cow s milk, human blood and spruce needles in an areas of PCDD/PCDF contamination through emissions from a metal reclamation plant. Chemosphere 21(12) 1451-1456. 

Plant substances are said to enhance some insect hormones, to the advantage of the insect. Bedard et al. (44) have described how the western pine beetle (Dendroctonus brevicomis) uses its host pine trees (Firms ponderosa and P. coulteri) to enhance the drawing power of its sex attractant, exobrevicomin. When ready to mate, both sexes emit the attractant. Bedard found the attractant s power (in terms of numbers of insects attracted) was doubled when mixed with myrcene, a normal constituent of pine wood. Myrcene alone was not attractive. Myrcene, however, is not restricted to pine we have seen earlier (10) that it is consistently found in spruce needles, and in general it is not characteristic of any single group of plants. Since the western pine beetle feeds only on pine, of what real ecological significance is Bedard s report of the enhancement of its hormone by myrcene Why isn t a more specific constituent of pine wood involved Perhaps one is, but research has not yet revealed it. Apart from Brower s work with the monarchs, we have not examined the rich area of herbivore—predator interactions. 

Note that there is a difference in effective Ej (L) of different ages in spruce needles. 

Figure 12 Decomposition dynamics of Spruce needles as indicated by increasing depth in the litter layers (S, L, FI, F2, and Fb). Fb = F layer that has been invaded by white-rot fungi (after Gourbiere, 1982).

TRACE ELEMENTS IN BEECH LEAVES AND SPRUCE NEEDLES 6.6.1. Introduction... 

Some years ago the first reports appeared on forest die-back in heavily polluted areas. The impact of this information drew the attention on the situation of local forests, which encouraged research on acid deposition in many countries. The quantitative evaluation of damage and the monitoring of forest quality are difficult. Most theories have been based on visual inspections however, trends, actual damage and local effects can only be estimated on the basis of scientific measurements, enabling to make correlations between damage and measured pollutant concentrations. A prerequisite for this evaluation is the availability of representative CRMs. The BCR has hence developed for this purpose two reference materials, namely beech leaves and spruce needles, which have been certified for nutrients (e.g. Ca, Mg, K, P and N) and indicator elements (e.g. S, Cl, A1 and Mn) [17-19],... 

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