Photosynthese,Transpiration und Spaltöffnungsverhalten verschiedener Holzarten nach Begasung mit SO2

Photosynthesis, transpiration and stomatal response of various species of woody plants exposed to sulfur dioxide. Photosynthesis of Fraxinus excelsior, Piceaabies, Abies alba and Pinus sylvestris declined after 6 and 12 h of fumigation at SO₂ concentrations of 5 and 9mg m^?3. Transpiration also declined, but the maximum depression was only 38%. Stomata began to close after fumigation with ～ 1 mg SO₂m^?3 for 6 h. The diffusion resistance of needles of Pices and Abies increased after fumigation with 9 mg SO₂ for 6h to a peak value of 35–40 scm^?1 and decreased rapidly (Picea) or remained stable (Abies) during the following 30h.     

Effect of simulated acid rain on the growth performance of the European pine sawfly [Neodiprion sertifer)

The effect of simulated acid rain on the performance of Neodiprion sertifer larvae fed on treated Scots pine needles was tested in a subarctic area with low ambient pollution level. Acid rain treatments (pH 4 and pH 3, both with H₂SO₄ and HNO₃) did not significantly affect the relative growth rates or cocoon weights of N. sertifer 2 or 3 years after the start of the treatments. The relative growth rate of N. sertifer larvae was slightly (nonsignifi‐cantly) higher on plots receiving only ambient rain than on irrigated control plots. The quality of foliage before the start of the treatments explained a significant proportion of the variation in the performance of N. sertifer larvae in the bioassay conducted 3 years later.     

Sulfur dioxide-induced growth changes in Eucalyptus calophylla

Eucalyptus calophylla Lindley exposed to two levels of sulfur dioxide continuously for 120 days in open top chambers, showed contrasting changes in resource partitioning. Exposure to 125 μg m^?3 of SO₂ had an apparent fertilization effect with increase in the weight of stems and total above ground plant weight whereas 261 μg m^?3 had a toxic effect with a reduction in the total number of leaves. SO₂ had no effect on leaf protein or chlorophyll concentration nor on visible injury.     

Determination of mean diameter by basal area in stands of picea abies and pinus sylvestris in southeastern Norway by means of aerial photographs

Mean diameter by basal area (d_g) is an important stand variable for long‐term economic forecasts of forest holdings. In order to use stand‐by‐stand surveys based on aerial photo interpretation as the data basis for forecasts, d_g has to be determined. The objective was to develop and test a regression function for d_g in mature stands of Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) applicable in southeastern Norway. A study of 700 plots was used to estimate a function for d_g . An additive model was found to be most suitable. The independent variables were potential yield capacity, Lorey's mean tree height, crown closure determined by ocular estimation by means of aerial photographs, and the product of potential yield capacity and crown closure. The R² value was 0.604 and the coefficient of variation was 10.8%. The regression fitted most parts of the calibration data quite well, but it may overestimate the mean diameter in pure spruce stands by 1–2%, and underestimate the diameter in pure pine stands by 3%. For mixed coniferous stands the regression seems satisfactory. Testing by means of an independent data set showed systematic errors of 3–23%. The systematic errors were due partly to calibration problems in connection with the ocular crown closure estimation.     

CO2 fluxes of a Scots pine forest growing in the warm and dry southern upper Rhine plain, SW Germany

The effects of the warm and dry weather in the southern upper Rhine plain in the southwest of Germany on the carbon balance of the Scots pine forest at the permanent forest meteorological experimental site Hartheim were analysed over a 14-month period. The investigation of the net ecosystem exchange of carbon dioxide (F _NEE) of the Scots pine forest started in the extraordinary hot and dry August 2003. Carbon dioxide fluxes were measured continuously using an eddy covariance system and analysed by use of the EDDYSOFT software package. After determining the temperature dependence of the forest ecosystem respiration and the daytime light dependence of the CO₂ exchange, monthly and annual carbon balances of the Scots pine forest were calculated. Mean peak daytime F _NEE rates observed in August and September 2003 (−6.5±3.6 μmol m⁻² s⁻¹) were drastically lower than in August and September 2004 (−11.8±5.2 μmol m⁻² s⁻¹), which did not show pronounced deviations from the mean long-term (1978–2002) climatic conditions. In August 2003, the Hartheim Scots pine forest was a distinct CO₂ source (35 g C m⁻²). The estimates of the annual carbon sink strength of the Scots pine forest ranged between −132 g C m⁻² (August 2003–July 2004) and −211 g C m⁻² (October 2003–September 2004). The main uncertainty in the determination of the carbon balance of the Hartheim Scots pine forest was introduced by the frequently low turbulence levels, i.e. the friction velocity corrected night-time F _NEE fluxes.     

Potential for Biological Control of Botrytis cinerea in Pinus sylvestris Seedlings

Grey mould (Botrytis cinerea Pers.: Fr.) is the most common economically important fungal disease in Swedish forest nurseries. In tests in a growth room, foliage of predisposed (preinoculation incubation at 35°C for 4 days) Scots pine (Pinus sylvestris L.) seedlings was sprayed with suspensions containing Mycostop®, Binab® TF.WP or GlioMix® at concentrations of 0.5, 1 or 0.5 g l^?1, respectively, and/or conidia of B. cinerea (10⁶ spores ml^?1). Binab and GlioMix reduced grey mould in needles by 94 and 92%, respectively, and were as effective as the fungicide Euparen® M 50 WG, while Mycostop reduced disease by 51%. In one trial in a forest nursery, Mycostop, Binab and GlioMix, each applied two and four times during the growing season, suppressed spontaneous B. cinerea infections in needles of first year container-grown P. sylvestris seedlings by 16–57%, and were as effective as recommended fungicidal sprays. It was concluded that biological control has potential to effectively suppress grey mould in seedlings in forest nurseries.     

Effect of heavy metal pollution of forest soil on radial growth of Scots pine

A field experiment with artificial soil contamination by the heavy metals copper and nickel was established in Kola Peninsula, northern Russia. To study the effect of soil contamination by heavy metals without SO₂ air pollution on the Scots pine trees growth the experiment was located outside the range of forest damage due to emissions from a copper–nickel smelter. Retardation in tree diameter growth over 15 years after contamination with 20 kg of metallurgical dust per 100 m² plot was 54%, 10 kg 27%, 5 kg 16% and 2.5 kg 7%, respectively, compared with growth in control plots. Thus, decreasing Scots pine growth due to heavy metal pollution was demonstrated.     

Carbon footprint including effect of carbon storage for selected wooden facade materials

Abstract

The outer facade constitutes a substantial volume of the total consumption of materials used in a building and the need for maintenance of the facade makes it especially interesting from a life cycle perspective. The range of wooden materials and products used for facades has different impacts over the life cycle, but the analyses so far have not included a time-adjusted global warming potential (GWP). Wooden facade materials were assessed with respect to their life cycle carbon footprint based on the environmental product declarations (EPD) and adjusted according to EN15804. The results showed low impacts of untreated Scots pine heartwood (≈1 kg CO₂-eq. per square meter [m²]), medium for thermally modified Scots pine, coated Norway spruce and oil/copper–organic preservative-treated Scots pine (1–5 kg CO₂-eq. per m²) and high for furfurylated Scots pine and acetylated Radiata pine (5–10 kg CO₂-eq. per m²). The results with time-adjustment showed that these methods have a potential large effect on the carbon footprint of wooden claddings. The inclusion of biogenic carbon flows and timing seems to be more important than the difference between the product when biogenic carbon is not included. This fact highlights the importance time-adjusted GWP would have for wood products EPDs.     

Phosphorus supply and cycling at long-term forest monitoring sites in Germany

In this study, the supply and input–output balances of phosphorus (P) were investigated for a 10-year-period at 85 long-term monitoring sites in German forest ecosystems under the European Level II programme. These sites encompass 23 European beech (Fagus sylvatica L.) stands, 9 oak stands comprised of common oak (Quercus robur L.) and/or sessile oak (Quercus petraea Liebl.), 20 Scots pine (Pinus sylvestris L.) and 33 Norway spruce (Picea abies H.Karst.) stands. We quantified P concentrations in needles and leaves, P inputs from the atmosphere, P outputs through leaching and harvesting, and total P in the soil and humus layers. The P concentrations in European beech leaves from two sites (>1 mg P g⁻¹ dry weight), and in Norway spruce needles from four sites (>1.2 mg P g⁻¹ dry weight), were deficient over several years. In contrast, the oak and Scots pine sites were well supplied with P. When P removal through harvesting was disregarded, P balances were positive or stable (median 0.21 kg P ha⁻¹ a⁻¹). With harvesting, balances were mostly negative (median −0.35 kg P ha⁻¹ a⁻¹), with long-term P removal from the forest ecosystems.     

Responses of Pinus sylvestris and Picea abies Seedlings to Limited Phosphorus Fertilization and Treatment with Elevated Ozone Concentrations

Scots pine ( Pinus sylvestris L.) and Norway spruce [ Picea abies (L.) Karst.] seedlings were exposed to high phosphorus (HP) or low phosphorus (LP) availability for one growing season in the open field, and to combined P availability and elevated ozone (O 3 ) concentrations (0, 55, 110 and 210 ppb for Scots pine and 0, 40, 75 and 150 ppb for Norway spruce, respectively) for 28 days in controlled laboratory chambers. Compared with HP, the LP treatment reduced Scots pine current-year (C) shoot and root dry masses and Norway spruce total dry mass, whereas the highest O 3 concentrations increased the magnesium concentration of Scots pine C needles and P concentrations of the C needles of both tree species. Chlorophyll a, a+b and carotenoid concentrations of Scots pine C needles were significantly higher in the LP treatment compared with HP under the highest O 3 concentration (210 ppb). In the mesophyll tissue of C needles of both tree species, LP treatment increased the size of mitochondria and elevated O 3 -induced granulation of chloroplast stroma and disintegration of cytoplasm. Exposure to elevated O 3 concentrations increased swelling of chloroplast thylakoids and reduced the amount of vacuolar tannin in the LP Scots pine C needles. The results suggest disturbances in needle photosynthetic machinery due to acute exposure to the combination of elevated O 3 and low P availability. However, clear additive effects were found only in needle P concentrations < 1 mg g -1 in short-term O 3 exposure.     

Long-term variation in Scots pine seed crop size and quality in northern Finland

Abstract

Quantitatively and qualitatively good Scots pine (Pinus sylvestris L.) seed years are rare in northern areas because of the short growing seasons. The seed crop size was studied in four natural pine forests in northern Finland during 1960–2004. Data on seed crop quality were collected during 1986–2004 and quality was determined by X-ray radiography. The long-term average annual seed crop of pine was 77 seeds m^?2, varying from 5 to 225 seeds m^?2. The expected average annual germination percentage of the seed crop was 61%, varying from 7 to 81%. General linear models were used to analyse the size and quality of the seed crop. Independent variables explained 52% of the variation in annual seed crop quality, and no proper model was found for determining the size of the seed crop; the coefficient of determination was only 5%. A combination of more than 100 seeds m^?2 and an expected germination percentage of over 50% was observed once during the years 1986–2004. In most years, natural regeneration in northern Finland is difficult and often limited by the seed crop's quality as well as quantity. These results confirm the importance of seed tree cutting in abundant seed crop years to enable the natural regeneration of pine.     

Irradiance in young stands of picea abies (L.) karst. and pinus sylvestris L. and the possibilities to prevent suckers of broad‐leaved trees

Incoming shortwave global radiation (Q _g) and photosynthetically active radiation (PAR; Q _pa as a fraction of full daylight, relative irradiance (%Q), were measured at the same time in young stands of Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.). Measurements were made on three levels above ground: 20 cm above ground and 50 and 15 % of stand height. Stands of three heights (75, 150 and 300 cm) were studied during two months. The stands were created by arranging young trees cut from natural stands, in nine quadratic spacings: 0.1, 0.2, 0.3, 0.4, 0.5, 0.7, 1.0, 1.4 and 2.0 m. The leaf area index (L) was estimated. Differences in %Q‐values for Q _pa and Q_g in the same species and at the same stand height and level of light measurements above ground were significant only in 150 and 300 cm stands. In 75 cm high stands of Scots pine, the %Q was <60% at spacings <0.2 m and in 75 cm high stands of Norway spruce, the %Q was <60% at spacings <0.3 m. Only at 0.1x0.1–0.3x0.3 m, %Q was <20% in Norway spruce stands. In 150 cm stands %Q<20% was measured at spacings <0.7 m in Norway spruce and <0.5 in Scots pine. In 300 cm stands of Norway spruce it was measured up to 1.2 and in Scots pine <1.1 m. Light extinction coefficients, K and K_g for spruce and pine stands were 0.17–0.40 and 0.16–0.31 respectively. Some practical implications of the study are presented. Lack of light (%Q<10%) as a single factor of seriously suppressed growth and development of broad‐leaved plants and suckers by competition in young stands of spruce and pine only occur in dense stands 0.3x0.3 m‐1.1xl.l m (8000–100000 stems/hectare). Competition by light on a regenerated area generally occurs in the level of 50% of tree height (150–300 cm) and higher due to the rapid growth of broad‐leaved trees (sprouts) compared with planted conifers but the light intensity at these levels %Q>10%.     

The effect of scalping on seedling establishment after seed tree cutting of Scots pine stands in drained peatlands in northern Finland

We studied the establishment of natural seedlings after seed tree cutting and scalping in two drained Scots pine peatland stands in northern Finland (Simo and Sievi). Approximately, 50?ha^?1 of Scots pine stems were retained on both sites. During the six subsequent years, five seedling surveys were conducted. The effect of site preparation was analysed using generalized linear mixed models (GLMM). The mean density of pine seedlings increased more quickly in the scalped plots and was ca. 1.1?m^?2 after six years compared to 0.87?m^?2 in the non-scalped plots, on average. Scalping increased the number of pine seedlings 2-fold compared to that in non-treated plots in Simo, however, in Sievi non-treated plots had 30% higher pine seedling density after six years. Downy birch seedling density was 9–10-fold compared to that of non-treated plots in both sites. In terms of seedling density, seed tree cutting led to satisfactory pine regeneration after just two growing seasons in drained pine peatlands, even without scalping. Scalping significantly increased the number of pine seedlings, but it also enhanced the germination of birch seedlings strongly.     

Apoplastic and total peroxidase activities in Scots pine needles at subarctic polluted sites

A gradient survey was carried out in order to compare peroxidase activity in Scots pine (Pinus sylvestris) needles in relation to distance from the industrial centre of Monchegorsk, on the Kola Peninsula in north-western Russia. Apoplastic and total peroxidase activity and sulphur (S), nickel (Ni) and copper (Cu) content in the needles of mature trees were measured on seven plots located between 10 and 110 km from the pollution source. Peroxidase activities in both current- and previous-year needles increased towards the smelters and showed a positive correlation with needle S, Cu and Ni concentrations. Total peroxidase activities showed a more obvious relationship to the pollution gradient in winter than in autumn. The element contents in the current year needles averaged 1649 ppm (S), 128 ppm (Ni) and 118 ppm (Cu) close to the smelters, 1212 ppm (S), 37 ppm (Ni) and 67 ppm (Cu) at a distance of 40 km and 831 ppm (S), 7 ppm (Ni) and 1 ppm (Cu) at the most distant sampling plot.This study showed that both the apoplastic and total peroxidase activities responded to heavy metal and sulphur pollution up to 40 km from the smelters in winter, which indicated an increased oxidative stress in this area. The harsh climate conditions and the high pollution levels may have had additive effects. However, as peroxidases are considered a general indicator of stress, it is not possible to evaluate the extent to which single pollutants contribute to this enzyme activity.     

Geological controls on conifer distributions and their implications for forest management in Finnish Lapland

Abstract

Soil water and nutrient regimes of naturally established old-growth conifer stands and those of intensively managed Norway spruce [Picea abies (L.) Karst.] sites were assessed over a range of lithological provinces in Finnish Lapland. Soil dielectric permittivity (ε), as a measure of soil water content (θ _v) and soil electrical conductivity (σ _a), as a measure of soil solute content, were species specific, such that high soil θ _v>0.27 cm³cm^?3 (ε>15) constitutes an edaphic constraint for Scots pine (Pinus sylvestris L.) and low soil solute content (σ _a<0.5 mS m^?1) is constraining for Norway spruce. The spatial pattern of the soil θ _v was temporally stabile, such that intraseasonal and interseasonal soil θ _v was significantly higher in silty tills of spruce stands compared to sandy tills of pine stands. Scots pine was the only conifer on tills derived from felsic rocks of Hetta granite (HG) and Lapland granulite (LG). Norway spruce dominated on tills derived from the mafic rocks of Lapland greenstone belt (LGB), but tills of LG and HG constitute a dispersal barrier for spruce. Mechanical site preparation (MSP) with ploughing (Marttiini) was not able to amend soil θ _v to meet site requirements of Scots pine at former spruce sites. MSP resulted in significant reduction in soil nutrient content such that untreated control σ _a>tilt/shoulder σ _a>trench σ _a. The results imply that MSP treatments through which cross-contour tracks are created pose a risk to the sustainability of soil quality in Lapland.     

Effects of growth regulators on germination of picea abies and Pinus sylvestris seeds

Nine seed lots each of Norway spruce (Picea abies L.), and Scots pine (Pinus sylvestris L.) were treated with combinations of the growth regulators: Indole‐3‐acetic acid, indole‐3‐butyric acid, etephone, kinetin, fusicoccin, and the gibberellins A₁ A₃ A_4/7, and A₉. GA₉ GA_4/7 and fusicoccin significantly promoted the germination of five Norway spruce, and three Scots pine, seed batches. Independent of species, the germinability of seeds treated with auxins, etephone, kinetin, GA₁ and GA₃ were unaffected or reduced. The rate of germination was stimulated for both species when treated with GA₉ or GA_4/7. The germination percentage for Scots pine seeds was enhanced by GA₉ but not by GA_4/7. Neither of the two GAs enhanced the germination percentage of Norway spruce seeds.     

Long-term effect of wood and peat ash on the growth of Pinus sylvestris on drained peatland

The effect of ash fertilization on height growth and volume production of Scots pine (Pinus sylvestris L.) was studied on oligotroph peatland in southeast Norway. In the year 1944, plots 15 m × 15 m size were fertilized with 0, 4, 7, and 10 tons ha^?1 of wood or peat ash. The area was treeless, but a satisfactory number of pine seedlings were present. All measurements were confined to the central inner plot, 10 m × 10 m area. Most plots were re-fertilized with 10 tons of wood ash ha^?1 in the year 1993. Wood ash had higher content of nutrients, and generally, it had greater growth enhancement effect than peat ash. When the amount of ash was increased, volume production significantly increased for the age period 38–50 years and the total production at age 50 years. The mean annual increment during the first 50 years was about 6 m³ ha^?1 for the plots applied with 10 tons of ash ha^?1. Trees on plots fertilized with 7 or 10 tons in 1944 and replenished with 10 tons ha^?1 at age 50 years (1993) had a mean annual increment of 14 m³ ha^?1 for the stand age period 51–68 years. Over time some tree roots from control plots and plots fertilized with 4 tons ha^?1 have captured nutrients from richer plots. Such effect is to a smaller extent relevant for treatment 7 tons. It is concluded that the content of mineral nutrients of wood and peat ash makes these ashes well suited as fertilizers on peatland.     

Distribution of root biomass in a low‐shrub pine bog

The average stump and below‐ground biomass of pine was 1464 g/m²; 4% as fine roots (Ø<1 mm), 18% small roots (Ø=1–10 mm), 49% large roots (Ø>10 mm), and 29% stumps), which comprised 35% of the total biomass in the Scots pine stands. The average root length of pine was 728 m/m²: 71 % of this length was fine roots, 29% was small roots, and less than 1 % was large roots. Most of the fine pine roots (80%) were in the 0–10 cm peat layer. The root biomass of the field layer was 548 g/m², which comprised 47 % of the total field layer biomass. Characteristic features of the root systems were: high below‐ground/above‐ground ratios, rather low amounts of root biomass, shallow rooting, and relatively thin roots. Hummocks tended to have less roots in the 0–10 cm layer and more roots in the 10–20 cm layer than the hollows.     

Nitrogen cycling in Pinus sylvestris stands exposed to different nitrogen inputs

The objective of this study was to quantify the effects of high nitrogen (N) inputs on N cycling in a 35–45-yr-old Scots pine (Pinus sylvestris L.) forest. Nitrogen was added annually (single doses) as NH₄NO₃ in doses of 0 (N0), 30 (N1) and 90 (N2) kg N ha^?1 yr^?1. The only N input to the N0 plots was atmospheric deposition of 10 kg N ha^?1 yr^?1. The N cycle in these plots was tight, with almost complete retention of the incoming N. In the N1 plots the N retention was 83% after 9 yrs of N addition. The trees were the major sink, but the soil also contributed to the N retention. In the N2 plots the N retention was 63%, being mainly accounted for by accumulation in the soil. The leaching of N from the N2 stands was as high as 35 kg N ha^?1 yr^?1. The N2 system was N saturated.     

Decomposition responses of pine (Pinus massoniana) needles with two different nutrient-status to N deposition in a tropical pine plantation in southern China

? The effect of nitrogen (N) deposition on the decomposition of pine (Pinus massoniana) needles in a tropical pine plantation was studied. The pine needles with two different nutrient status (nutrient-rich and nutrient-poor) were used, followed by 3-levels of N treatments (Control: no N addition, Low- N: 5 g N m^?2 y^?1, and Medium-N: 10 g N m^?2 y^?1 experimental inputs), which had been applied for 26 months continuously before this experiment and continued throughout the decomposition measurement.

? The main objective was to test the hypothesis that decomposition of nutrient-rich needles would be more sensitive to cumulative N deposition than the decomposition of nutrient-poor needles.

? Nitrogen addition had negative effect on mass loss, and the release of N and P from decomposing nutrient-rich needles but little or no effect on the decomposition of nutrient-poor needles. In addition, a negative effect in the initial decomposition phase and a positive effect in later decay stages were found on C release. The negative effect was stronger on nutrient-rich needles than on nutrient-poor needles, but the reverse was true for the positive effect.

? Our results suggest that response of litter decomposition to N deposition may vary depending on the nutrient status of the litter.