Pollution pine needles

Calorimetry shows that the rates of metabolism of plant tissues vary widely with species, with cell types, and with environmental conditions. This provides a means of exploring the mechanisms by which various agents influence the health of a plant community. Studies are being done on beneficial agents such as growth promoters and detrimental ones such as atmospheric pollutants. For example, a correlation has been found between the metabolic heat rates and the extent of damage to pine needles by ozone. 

Berg, B., Ekbohm, G., Soderstrom, B., and Staaf, H., Reduction of decomposition rates of Scots pine needle litter due to heavy-metal pollution, Water, Air, Soil Pollut, 59 (1), 165-177, 1991. 

Jensen S, Eriksson G, Kylin H (1992) Atmospheric pollution by persistent organic compounds monitoring with pine needles. Chemosphere 24 229-245... 

An example of a highly efficient interception system is the canopy of a coniferous forest. The large specific surface area of pine and spruce trees exceeds that of broadleaved deciduous trees, giving them a high scavenging efficiency for radioactive aerosol particles. Pine needles have been acknowledged as useful monitors of atmospheric pollution (Eriksson et al., 1989). However, radionuclides will be redistributed in the forest ecosystem due to various removal mechanisms such as rain... 

Eriksson, G., Jenson, S., Kylin, H. and Strachan, W., The pine needle as a monitor of atmospheric pollution. Nature, 341 (1989) 42-44. 

Vegetation samples are easier and more economical to collect than air samples. Moss (Hypnum cupressiforme) has no root system so pollutant uptake is only from the atmosphere. " Pine needles have also been sampled to determine ambient PAH concentrations. Although vegetation concentrations do not directly measure atmospheric concentrations, they allow for monitoring PAH deposition over a large area for a long time period. 

Lichens, especially epiphytic lichens, are increasingly used to monitor air pollutants emitted by vehicles and by a wide range of industrial enterprises. Many publications showed that vehicular and industrial activities are the main source of heavy-metal air-pollution. Mosses, lichens, pine needles and tree bark and leaves are widely used to... 

WALDMAN, J.D., AND M.R. HOFEMANN. 1988. Nutrieit leaching from Pine needles impacted by acidic cloud water. Water Air Soil Pollut. 37, 193-201. 

Many studies utilize biomaterials as pollutant sorbents, such as plant samples, e.g. bark [120-123], lichen or pine needles [117,123-125], to monitor ambient air concentrations assuming that their spatial pollution distribution in the plants and the atmosphere will be closely related. However, the concentration capacity and sampling rate of plant tissues vary with the plant species and age, location and season. Therefore, these kinds of plant data are still subject to several imcertainties, which complicate their interpretation and limit the potential of plants as monitoring tools. For this reason, man-made passive air samplers are preferred up to date, despite their additional costs and that they have to be deployed, since the variability of samplers at different loeations is low, and the sampling period can be controlled. 

Pines. Calorimetric studies of growth rates and temperature responses have not been employed to examine pine trees. Two studies were conducted to analyze effects of air pollutants on the respiration properties of Ponderosa and Jeffrey pine needles. Bower [104] used one-cm needle segments and demonstrated a correlation between the extent of ozone damage, measured as the number of lesions on the needles, and isothermal metabolic heat rates. He also measured increases in metabolic heat rates resulting from acid and nitrate deposition on the needles. Momen et al. [105] conducted a more controlled study of acid rain and ozone effects on Ponderosa pine with defined applications to plantation grown plants. In seedlings, metabolic heat rates increased in response to ozone and combinations of ozone and acid rain. Mature tree metabolic activities showed no response to ozone, acid, or combinations of the two. No studies were made to determine whether metabolic efficiencies were altered by these treatments. Thus the results show that calorimetry can be used to monitor pollutant effects on trees, but more definitive experiments must be done to identify how the ob.served responses relate to growth and survival of the trees. 

Houston and Houston and Stairs did clonal repeatability analyses to determine genetic control of tolerance in white pine with an ozone-sulfiir dioxide mixture and a 6-h exposure. Th used needle elongation and two injury estimates in assessing effects. The repeatability estimates indicated that tolerance to the pollutant mixture is under genetic control. The nature of the inheritance of tolerance is still not understood, but field selection of tolerant or susceptible individuals is possible. Demeritt et reported an evaluation system that used... 

Chen, J.W., Zhao, H.M., Gao, L.N., Henkelmann, B., Schramm, K.W., 2006a. Atmospheric PCDD/F and PCB levels implicated by pine (Cedrus deodara) needles at Dalian, China. Environ. Pollut. 144, 510-515. 

Costonis et al. (33) were unable to demonstrate a positive correlation between ambient sulfur dioxide levels and inorganic sulfur ion accumulation in the needles of pines which are injured by relatively low levels of sulfur dioxide in the air. White pines growing in air polluted with more than 0.25 ppm of sulfur dioxide are often stunted, and a direct correlation can be obtained between plant growth and ambient S02 levels (34). However, tissue analysis does not reveal a measurable rise in sulfur level as inorganic sulfate ions. It is posible that the excess sulfur is incorporated into cell protein, but the data conflict (28, 35). For these reasons, it is not possible to follow sulfur accumulation in plants chronically exposed to low levels of ambient S02 without resorting to labeled S02. 

At Pennsylvania State University, breeding for resistance to ozone and S02 in scotch pine is underway. Resistance seems to be genetic. Selections for resistance were made initially in a fumigation nursery and will be tested further in stands planted near pollutant sources. Crosses are being made for genetic studies as well as for selection for resistance and for favorable ornamental traits of crown form, branching habit, and needle color (15). 

Toxic to aquatic organisms for example, there was an inhibiting effect of 20-40 ppm aniline on the pigmentation of Xenopus laevis embryos, and of a concentration as low as 1 ppm on the body size of the young toads. Investigation of the death of pine trees in the United States found air pollution from aniline as the most likely causal agent for the needle necrosis and needle abscission. 

In the eastern part of Holland, premature senescence of needles of Scots pine and Douglas fir has been found over a wide area, and in May 1983 acute damage to pine trees was discovered in places. Subsequent tests revealed no evidence of attack on the roots by pathogens or by fungi, and acid rain is considered a possible cause. It is also of note that in 1974 damage to pine trees was found near Rouen, France, which exhibited symptoms similar to those found in the Black Forest and more recently in parts of Italy, air pollution is believed to be a contributory cause of similar stress found with pine trees. 

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