Der Nachweis winterlicher SO2-Immissionen an jungen Fichten Ein Vergleich dreier Methoden

The detection of winter SO₂ pollution effects on young spruce. A comparison of three methods. The suitability, sensitivity and tediousness of three methods (turbidity-test, peroxidase activity, buffering capacity) were compared for detecting the effect of SO₂ pollution in winter on spruce seedlings. Buffering capacity failed to detect a difference between controls and fumigated trees. Turbidity test and peroxidase activity yielded statistically significant differences. The turbidity test is less tedious but also less sensitive than peroxidase activity and its use is restricted to conifers.     

Über die Ursachen und Kriterien der Immissionsresistenz bei Fichte,Picea abies (L.) Karst.

Causes and critcria of resistance to air pollution in Norway spruce. II. Reflexive resistance . The different reactions of stomata of resistant and “normal” spruce grafts were investigated. Resistant grafts were shown to have a more sensitive reaction by measuring water potentials and by analyzing S content in SO₂ fumigated needles or F contents in grafts exposed to polluted air. Other tcsts involving gas permeability of stomata, clecrrical conductivity of needle cxtracts and watcr content of SO₂ fumigated needles were less effective.     

Einfluß niedriger SO2-Konzentrationen auf die Aktivität einiger Glykosidasen der Assimilationsorgane verklonter Waldbäume

Effect of low SO₂-concentrations on the activities of some glycosidases in the foliage of clonal forest trees. The aim was to find an early indicator of latent SO₂ injuries in a beech and a spruce clone. After exposure to 0.0, 0.05, 0.1 and 0.2 ppm for several weeks in outdoor fumigation chambers, the activities of β-glucosidase in the beech and β-galactosidase in the spruce clone and β-l,3-glucanase in both species were significantly raised. As the beech clone was very sensitive to SO₂, an indication of latent injury could be ascertained only in the 0.05 ppm treatment where the rise of the β-glucosidase activity appeared some days before necroses. Contrary to beech, the spruce clone was tolerant to all SO₂-treatments and the enzymatical changes could be used as early indicators of latent injuries.     

Peroxidase- und Superoxiddismutase-Aktivität sowie Prolingehalte von Fichtennadeln nach Belastung mit O3, SO2 und NO2

In long-term experiments the influence of various combinations of O₃, SO₂ and NO₂ on peroxidase activity, superoxide dismutase activity as well as on proline contents of spruce needles was studied. The reactions of these parameters varied depending on the type of pollution and the needle age. Peroxidase and superoxide dismutase activity were also influenced by Mg and Ca supply of the plants.     

Response of spruce stands in national parks of southern Poland to air pollution in 1998–2005

The purpose of this study was to describe changes in the deposition of air pollutants and the response of spruce trees in the period of 1998–2005. The investigation was carried out in twelve sites, mainly national parks. Air pollution level, that is, SO₂, NO₂, and O₃ concentrations in the air, as well as throughfall and soil solution chemical composition was analysed. The reaction of trees was described based on a stand health parameter, that is, defoliation. A decrease in the concentration of SO₂ and NO₂ in the investigated period was observed. In most of the analysed sites, ozone concentrations in the growing season exceeded the level regarded as harmful to plants. Annual loads of nitrogen and sulphur reaching the forest soil exceeded 10 kg/ha. The data collected for the analysed period confirmed that the health status of forests at the investigated sites did not show a general tendency towards improvement. Also, no dependency between the air pollution level and defoliation rate was found.     

Cystein und Glutathion in gesunden und SO2-geschädigten Fichtennadeln

Cysteine and glutathione in healthy and SO₂ damaged spruce needles. SO₂ damaged and healthy spruce needles were analysed for water soluble SH groups. Total SH content was mainly due to glutathione with some cysteine. Increased cysteine content was found only in old needles. Total content of SH groups fluctuates seasonally in the same way in both healthy and damaged needles. SO₂ damaged needles, however, always contain more SH-groups than healthy needles except immediately after flushing.     

Über die Ursachen und Kriterien der Immissionsresistenz bei Fichte,Picea abies (L.) Karst1

Causes and criteria of resistance to air pollution in Norway spruce, Picea abies (L.) Karst. IV. Recovery of injured needles, connections between forms of resistance and summary of results to date. Water potential measurement of resistant clones of Norway spruce treated with SO₂ showed that they recovered better than control clones or were at least not so permanently affected. From a variety of experiments on fumigation, it was concluded that reflexive and “internal” resistance were associated. The results of the series of papers so far are summarised.     

Die Leitfähigkeit von Fichtenborken-Extrakten als empfindlicher Indikator für Luftverunreinigungen

The Conductivity of Bark-Extracts from Spruce, a Sensitive Indicator for Air Poilution . Bark of spruce is a useful and sensitive indicator for air pollution. The latter may be determined more precisely by electrolytic conductivity of bark extracts than by pH-value or sulphate level of foliage. By an additional simple sulphate analysis of bark extracts the effects of SO₂ may be distinguished from those of certain components in dust.     

Application of a polymeric coating can protect coniferous trees from acute pollution injury

SO₂ and NO_x are main primary pollutants which often occur together in Europe. In three experiments small spruce trees were exposed to SO₂ or to SO₂ + NO₂ in controlled environmental conditions. A polymeric coating (spodnam), based on a natural terpenoid compound was applied to half the trees fumigated in each experiment and the influence of this material on the sensitivity to pollutant injury was observed. Picea abies and Picea rubens (Norway and Red spruce) were more sensitive than Picea sitchensis (Sitka spruce) to acute damage from 8000 ppb SO₂ experienced for 12-h periods during dormancy. A single application of 15% (ν/ν) of the polymeric coating substantially decreased the extent of acute injury in all three species. Dormant P. sitchensis fumigated with 250 ppb SO₂ and SO₂ + NO₂ also showed less pollutant injury at the end of a 2-month fumigation when 5% (ν/ν) spodman had been applied. Exposure of coated and uncoated seedlings of P. sitchensis to 400 ppb SO₂ during growth in 8-h and 16-h photoperiods confirmed the strong protective effect of a 15% (ν/ν) application. After 6 weeks in 16-h photoperiods, the coated plants grown in SO₂ had larger dry weights than uncoated plants in SO₂. Spodnam also caused decreases of dry weight which were greater in the 8-h daylength, indicating that growth rate was important in determining the physiological cost of having an additional coating over the foliage. Further analysis of the effects of the coating on plant growth and of its protective function against air pollutants are required to determine whether application would be beneficial in forest areas were large concentrations of gaseous air pollutants occur. The timing, concentration and degree of coverage achieved during application would influence the impact of this material; and the benefit gained would depend on the severity of pollutant damage and on the way in which spodnam effects other factors which influence growth.     

Peroxidase-Aktivität in Fichtennadeln unter Schadgasbelastung im Freiland und in Expositionskammern

Zusammenfassung Die Gesamt-Peroxidase-Aktivit?t in grünen, optisch gesunden Nadeln der Fichte (Picea abies L.) wurde im Freiland am Standort “Postturm” (Forstamt Farchau/Ratzeburg) in Tages- und Langzeitkinetiken und bei kurzfristigen Schadstoffspitzenwerten von SO₂ und Ozon untersucht. Parallel hierzu wurde der Wasserhaushalt der Nadeln, die Klimabedingungen und Lichtintensit?ten erfa?t. Unter kontrollierten Bedingungen erfolgte eine Behandlung mit Einzelschadgasen sowie eine Kombinationsbegasung von SO₂ und NO₂ auf die POD-Aktivit?t in Nadeln eines Fichtenklons. Die Ergebnisse zeigen, da? die POD-Aktivit?t Schwankungen unterworfen ist, jedoch keine signifikanten Aktivit?ts?nderungen in Abh?ngigkeit von der Schadgasbelastung zeigt. Die Untersuchungen führen zu dem Ergebnis, da? die Gesamt-POD-Aktivit?t im überstand des Gewebehomogenats von Fichtennadeln als Indikator für eine Umweltbelastung mit Schadgasen ungeeignet ist, da die Aktivit?t dieses Enzyms von zu vielen Faktoren abh?ngig ist.

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Activity of peroxidase in spruce needles in presence of gaseous pollutants in the field and under controlled conditions

Summary The activity of soluble peroxidase (POD, EC 1.11.1.7.) in green needles of about 100-year-old trees of Norway spruce (Picea abies L.) at the location “Postturm” near Ratzeburg, Northern Germany, was studied in relation to transitory increased concentrations of gaseous air pollutants (SO₂ up to 260 ppb in winter, and O₃ up to 130 ppb in summer). Significant changes of POD activity in response to pollution could not be observed. POD activity did not show diurnal variation, but seasonal changes, and changes in response to sunlight (sun needles versus shade needles) and in relation to needle age were observed as well as great variation between individual trees. Moreover, seven-year-old cloned spruce trees were exposed to SO₂, O₃ and NO₂ in growth chambers under simulated climatic outdoor conditions. Consistent with the field studies no changes in POD activity in response to the gaseous pollutants could be observed, although the concentrations applied were higher than in the field. It is, therefore, concluded that the activity of soluble POD is not a suitable indicator for the tested gaseous pollutants.

     

Eine einfache Methode zur SO2-Begasung von Fichtenpfropflingen im Labor1

A simple method for SO₂ fumigation of Norway spruce grafts in the laboratory. To investigate the resistance mechanism of Norway spruce to SO₂ a simple fumigation chamber was used. The conditions of fumigation gave the desired range of symptom expression.     

Einfluß von SO2 und HF auf freie Aminosäuren der Fichte (Picea abies [L.] Karsten)

The influence of SO₂ and HF on free amino acids of spruce . The influence of the air pollutants SO₂ and HF on composition and amount of free amino acids was investigated. Distinct differences in the pattern of amino acids are caused, particularly in glutaminic acid and compounds based on it.     

Rasterelektronenmikroskopische Untersuchungen an Stomata von Fichten- und Tannennadeln nach Begasung und saurer Beregnung1

Scanning electron microscopical investigations on stomatal wax plugs of fir and spruce needles after fumigation and acid rain treatment Alterations of stomatal wax plugs of fir and spruce needles have been investigated in order to demonstrate the effects of different air pollutants. After acid rain treatment, and in addition to SO₂ fumigation, heavily melted wax crystals were observed. It is assumed that acid rain causes mainly the changes of the stomatal wax plugs.     

S-Lokalisation in SO2-begasten Fichtennadeln

Localisation of sulphur in spruce needles treated with SO₂. After exposure to SO₂ the tips of spruce needles arc richer in sulphur compounds than the bases. The accumulation of sulphur compounds results mainly in an increased content of inorganic sulphur. The analytical results explain the local occurrence of injuries at the needle tips.     

Physiologische Reaktionen der Fichte (Picea abies) auf komplexen SO2- und Trockenstreß

Physiological reactions of spruce (Picea abies) on complex SO₂- and drought-induced stress. Part 3. Responses of SO₂-stressed spruces to subsequent drought-induced stress. SO₂-stressed spruces under drought-stress showed less reduced water content, less increased osmotical potential and less restricted photosynthesis compared to spruces without preceding SO₂-stress and thus seemed to be in a better physiological situation. Their ability to retain water (in cut-off twigs) as well as their ability to withstand a quick and strong water-loss in the needle-tissue without cell-damage were reduced. Reasons for the temporarily favourable effect of a pre-going SO₂-stress in surviving a drought-stress are discussed.     

Dendroecological assessment of the complex causes of decline and recovery of the growth of silver fir (Abies alba Mill.) in Southern Germany

Causes of decline and silver fir (Abies alba Mill.) mortality in Central Europe have been controversially discussed for a long time. This contribution details a comprehensive dendroecological investigation of two basic and alternative hypotheses that explain the decline by either climatic influences or by SO₂ pollution as the primary factors. Growth reduction between the 1960s and 1980s as well as the recovery of growth during recent decades have be seen as a response to complex interactions of multiple factors. Herein, we undertake a multidisciplinary evaluation of a broad database, representing the long-term growth of 1010 firs from 51 sites, long-term climate records as well as data assessing the long-term pollution situation in Southern Germany. The results provide clear evidence that SO₂-immissions play a key role in decline and that tree growth corresponds with the regional and temporal pattern of SO₂ pollution. Calculations with a new complex growth model indicate that tree-ring widths of fir at many sites were more influenced by SO₂ than by any other growth-determining factor during the second half of the last century. Strongest coherence between measured and modelled ring widths are found if – in addition to temperature, available soil water content, heavy frost events and long-term growth trends – the site-specific trend of SO₂ pollution is included. Both the immediate response to SO₂ pollution and the quick recovery of fir since the beginning of the 1980s after the decrease of SO₂ emissions indicate a direct impact of SO₂ in gaseous form and not via the soil in terms of soil acidification. Tree-ring widths document that radial growth response occurs at air concentrations above 10 μg SO₂ m⁻³ (annual average), which can be thought of as a critical threshold for silver fir health. Since the beginning of the 1980s, increasing growth trends have been observed which predominantly result from decreased SO₂ pollution in most parts of Central Europe, although climate change, fertilization by nitrogen deposition and a reduced tree-to-tree competition are also relevant factors. The drastic reduction of SO₂ emission during the recent decades significantly improved the environmental conditions for fir. Consequently, an increased cultivation of silver fir on suitable sites is recommended.     

A Comparison of Element Fluxes in Throughfall beneath Larch and Sitka Spruce at Two Contrasting Sites in the United Kingdom

Annual chemical fluxes for ten elements beneath larch and Sitkaspruce are presented for contrasting sites in N.E. Scotlandand mid-Wales. The Scottish site is relatively low altitudewith moderate rainfall and the Welsh site is relatively highaltitude with high rainfall; both sites have low air concentrationsof SO₂ and NO₂ The data show clear differences in throughfallelement fluxes between larch and Sitka spruce of similar ageand, for the same species, between the two sites. For sea-derivedions and Ca, the trees appear to respond differently to thecontrasting climatic and depositional environments at the twosites; this overrides any consistent differences between speciesfor these elements. Species related differences, consistentat both sites, are apparent for H ion, SO₄ and the major nutrients.Larch releases more K and P but retains more inorganic N thanSitka spruce. Beneath larch, the H ion flux is approximatelythree times and the SO₄ flux 1.5 times that beneath Sitka spruce,indicating that larch is more acidifying than spruce.     

Spruce bark influenced by SO2

Investigations into SO₂ absorption by spruce barks using artificial fumigation have proved that continued immissions of SO₂ alter the properties of bark making them capable of accumulating SO₂ up to amounts never attainable by barks grown in clean air. This can be recognized by the time lapse considering SO₂ absorption and by altered ion exchange as well as buffer capacity. With respect to the availability of the bark extracts for mapping SO₂ immissions in the field it is concluded that both conductance and sulphate content of bark extracts represent an integration covering a considerable preceding period being modified by the actual immissions.     

Über die Ursachen und Kriterien der Immissionsresistenz bei Fichte,Picea abies (L.) Karst

Causes and criteria of resistancë to air pollution in Norway spruce. 3. Tolerance of toxic materials (“internal” resistance). Comparing relatively resistant and not resistant Norway spruce clones, an attempt was made to find differences by investigating the relation of needle colour and absorption of sulfur, needle pH-value and buffer capacity, sulphur distribution within several of their needle components and within the total plant, the ratio of organically fixed sulfur to total sulfur content of noedles, and content of sulfhydril groups, protein and chlorophyll of needles. Significant differences were shown only in buffer capacity of unfumigated needles, and in thc propornon of organically fixed sulfur before and after SO₂ fumigation.     

The influence of SO2 on CO2 uptake and peroxidase activity

This study confirms that CO₂ uptake of European conifers increases during needle maturation. Extensive investigations with grafts of several species show that this increase may even mask a deleterious effect of a weak SO₂ stress. In plants which are not dependent on air-borne SO₂ for S nutrition CO₂ uptake was not favored by SO₂. Peroxidase activity of tree foliage may be a valuable stress indication, particularly in areas with light air pollution. It is, however, not specific for air pollution and seems to be most suitable for “active” monitoring.