Silva Fennica vol. 15 | 1981

The use of forest mosses as bioindicators was tested with transplanted experiments. One transplantation experiment was made to study effects of air pollutants on two forest moss species, Hylocomnium splendens (Hedw.) Schimp. and Pleurozium schreberi (Willd. ex Brid.) Mitt. Another transplantation was used to study the nitrogen fixation capacity of blue-green algae in the Hylocomnium and Pleurozium moss layers. The surface structure of the moss species was studied by scanning electron microscopy. The air pollution induced changes in the surface structure of moss cells were observable soon after the transplantation. In polluted industrial areas the fertilizing effect of air-borne nitrogen compounds increased the photosynthetic activity of mosses before their destruction. Stress respiration was also observable in polluted areas. The nitrogen fixing capacity decreased or was almost inhibited in all the air-polluted environments.

• Huttunen, E-mail: sh@mm.unknown
• Kallio, E-mail: sk@mm.unknown
• Karhu, E-mail: mk@mm.unknown

A comparison study concerning the effects of acid rain on Scots pine (Pinus sylvestris L.) seedlings has been performed. Two different X-ray fluorescence methods, PIXE and IXRF, were employed to produce multielement analyses of the samples. Seedlings were treated for 3 months with watering of pH=7 or pH=3 liquids on the needles and on the roots. One year and two years old needles of the seedlings were inspected for changes in photosynthetic rate as well as for changes in elemental concentrations.

Twelve elements from Si to Zn were compared in the samples. The PIXE results show that the amounts of most of these elements in the needles of the seedlings grown in sand increase, when treated with acid water. This growth is clearer when the roots are treated with acid water. The elemental concentrations of the needles in the seedlings grown in soil on the other hand decrease slightly.

• Raunemaa, E-mail: tr@mm.unknown
• Erkinjuntti, E-mail: re@mm.unknown
• Gerlander, E-mail: mg@mm.unknown
• Hautojärvi, E-mail: ah@mm.unknown
• Kaisla, E-mail: kk@mm.unknown
• Katainen, E-mail: hk@mm.unknown

Fertilizer factory has been found to be harmful to the surrounding area through its fertilizing effect, mainly due to nitrogen compounds in the form of NO_x and ammonium. In this study, pH, K, Ca and Mg contents in the humus layer were monthly monitored around a fertilizer industry in Oulu, Northern Finland, in 1975 and 1976. In addition, nutrient analyses were made in the leaves of Vaccinium vitis-idaea, V. myrtillus and Empetrum Nigrum.

The calcium, magnesium and potassium present in the emission of airborne fertilizer dust brought about an increase of the nutrient content of the surface top soil humus compared with the control samples. The nutrient contents of dwarf shrub leaves increased near the industrial site as compared with the controls. The potassium contents of Vaccinium myrtillus and Empetrum nigrum were exceptionally high. The results of this pilot study show that the overfertilization must have had an increasing effect on the nutrient status changes in the forest environment.

• Pakonen, E-mail: tp@mm.unknown

A model was constructed, the aim of which was to predict growth under conditions where air pollutants are present. The model is based on photosynthesis and on the allocation of photosynthetic products for growth. It is assumed that air pollutants released during energy production mainly affect photosynthesis in two ways: 1) directly by injuring the photosynthetic mechanism, and 2) indirectly by leaching nutrients. The two ways were studied empirically in order to identify a sub-model for the photosynthesis of a plant exposed to air pollutants. 

The stand model will be applied to two purposes. The present stage of forests in Finland is compared with the simulated state based on the assumption that no pollutants are present. In addition, the decrease in forest yield under different conditions derived from predictions about long-range pollutant transport in Europe is analysed.

• Mäkelä, E-mail: am@mm.unknown
• Hari, E-mail: ph@mm.unknown
• Kellomäki, E-mail: sk@mm.unknown

Several studies of air polluted forest environments have shown that dwarf shrubs suffer from air pollution. In many cases the disturbances have been attributed to the susceptibility of the dwarf shrubs, while in some cases the vegetational competition factor has been discussed. The growth pattern of dwarf shrubs is very complicated and a single individual can cover large areas due to vegetative reproduction. Since dwarf shrub individuals cannot be transplanted for the purpose of laboratory or field tests, the only possibility is to use small cuttings for the bioindication studies. Some preliminary results are discussed.

• Mikkonen, E-mail: hm@mm.unknown
• Huttunen, E-mail: sh@mm.unknown

The ultrastructure of Hypogymnia physodes (L.) Nyl. and Alectoria capillaris (Bryoria capillaris (Ach.) Brodo & D. Hawksw.) grown or transplanted near a fertilizer plant and a pulp mill was compared to normal ultrastructure of these lichen species. The ultrastructural changes observed were highly similar in the symbionts of both species and near both the factories although the emissions are different. In the lichens grown near the factories the number of algae had clearly increased. The appearance of the chloroplasts was roundish compared to controls. The pyrenoglobuli and cytoplasmic storage bodies were smaller than normally and the number of polyphosphate bodies had increased. Also, in mycobionts storage droplets were very small or absent and many vacuoles and dark inclusions appeared to hyphae in contrast to controls. In transplanted lichen there existed mainly the same ultrastructural changes as in the lichen grown near factories. Near the fertilizer plant the damage was, however, more severe because all the lichens died during 6–7 months after transplantation. Near the pulp mill part of the lichens survived and seemed to adapt to air pollution.

• Holopainen, E-mail: th@mm.unknown

A method to determine sulphur as sulphate has been applied to search for surface concentration of sulphate sulphur on needle samples. The method is based on reducing sulphates as volatile hydrogen sulphide gas by using hydriodic acid. The hydrogen sulphide gas is swept with nitrogen into an absorbent solution. Sulphide ion concentration in solution is then measured using ion selective electrodes.

The method was applied on one to four years old needle samples collected from Scots pine (Pinus sylvestris L.) at 0.9 to 15.9 km distances from a 1,064 MW coal-fired power plant in Southern Finland. Surface sulphate values found in the samples closer than 4 km to the power plant were 50 to 100% higher than a nearly constant background level. No significant variation of values with needle age was found. The advantages of the method compares to other methods for sulphur determination are speed, reasonable sensitivity and low detection limit.

• Hautojärvi, E-mail: ah@mm.unknown
• Ahonen, E-mail: sa@mm.unknown
• Erkinjuntti, E-mail: re@mm.unknown
• Katainen, E-mail: hk@mm.unknown
• Lappalainen, E-mail: tl@mm.unknown
• Raunemaa, E-mail: tr@mm.unknown

At immediate surroundings of a fiberglass plant in Central Sweden, vegetation shows toxicity symptoms. Soils and birch (Betula pendula Roth) leaves were sampled. The soil was analysed for water soluble and organic bound boron, carbon, nitrogen, and pH. Vegetation was analysed for total boron. Both fractions of boron in the soils increased towards the factory. Organic bound boron increased irregularly because of its strong correlation to carbon content which varied in the area. The C/N ratio increased nearer the industry due to the harmful effect of boron on the decomposition of organic matter. No relation between pH and the distance from the emission source was visible, but B/C ratio was found to increase with increasing pH of the soil. Boron levels in birch leaves were elevated very much close to the factory. The geographical distribution of high levels of boron in birch, corresponded well with high values in soils, and also with the main wind directions. The limit values for visible injury on birch were found to be around 5 ppm of water-soluble boron in soil and around 200 ppm in leaves.

• Eriksson, E-mail: je@mm.unknown
• Bergholm, E-mail: jb@mm.unknown
• Kvist, E-mail: kk@mm.unknown

Scanning Electron Microscopy was used to study structural changes in epicuticular vax of Pinus sylvestris L. with time. Changes in the contact angle of water droplets and in cuticular transpiration were also measured. By using material from a polluted and an unpolluted site it was shown that the ageing process occurs faster on polluted air, leading to greater cuticular transpiration and smaller contact angles at polluted sites.

• Cape, E-mail: jc@mm.unknown
• Fowler, E-mail: df@mm.unknown

Increased prices on oil have resulted in the search for alternative energy sources, e.g. coal, peat, biomass, different types of waste. Combustion especially of waste, coal and peat emits large quantities of air pollutants such as heavy metals but also harmful organic substances. Heavy metals are not easily separated from the smoke, and the concentrations are often high in the emissions even with advanced fly-ash separators.

Ecological investigations carried out around a coal burning power plant in Finland using mosses and pine needles as parameters are presented in the paper. Increased concentrations of Pb, Cd, Cr, Ni, Cu and V have been found near the plant. Often a clear gradient was found with increased concentrations at decreased distance from the power plant.

• Bramryd, E-mail: tb@mm.unknown

Air-borne Cu and Zn from a brass foundry at Gusum, SE Sweden, have considerably disturbed the lichen and bryophyte vegetation in the coniferous forest environment. The occurrence of lichens on Norway spruce twigs decreased rapidly with increasing Cu concentrations in Hypogymnia physodes above 90 ppm (background value 10–15). The epiphytic vegetation is reduced within 2–3 km from the foundry. Only stunted individuals occur in the close vicinity of the pollution source.

The cover of one of the quantitatively most important mosses, Hylocomnium splendens, is greatly reduced by the heavy-metal deposition. Cover values of 20–50% are not uncommon in distant sites (Cu concentration 15–35 ppm). There is a significant negative correlation between Cu concentration in the moss and its cover. The moss cannot survive much more than ca. 130 ppm Cu (and 360 ppm Zn). Live individuals are no more found within 1.5 km from the foundry.

• Folkeson, E-mail: lf@mm.unknown

Monitoring of heavy metal accumulation in plants has been used to reflect the deposition of heavy metals in terrestrial ecosystems. In some cases, the accumulation rates in plants are linearly correlated to deposition measured as bulk precipitation collected in funnel samplers. It is uncertain, however, how large the contribution due to adsorption/impaction of small particles is to this relationship. The need for design of enlightening experiments on deposition rates in different vegetation types and their relation to immission and bulk precipitation data is discussed.

• Johnsen, E-mail: ij@mm.unknown

A semi-statistical model is suggested for monitoring injuries of plants for long-time field exposures (months). The model is based on the following assumptions:

1. The concentrations of air pollutants in the atmosphere follow the Johnson SB distribution.

2. The degree of plant injury is proportional to the logarithm of air pollutant dose.

3. No injuries occur below a certain dose level.

4. A dose is defined as the air pollutant concentration multiplied by the duration of exposure raised to an exponent.

Based on the air pollutant frequency distribution a total dose for the exposure period is calculated by integration, and the total dose is related to the observed plant injury by non-linear regression. The model is tested for long-time exposures of sulphur dioxide to transplant lichen in natural environment.

• Moseholm, E-mail: lm@mm.unknown

A technique for instrumental scoring of damaged leaves on tobacco (Nicotiana tabacum) indicator plants caused by ozone in the lower atmosphere is being developed. The leaves are photographed in situ with an integrated unit, which illuminates the leaf from behind and keeps the camera in a well-defined position. By using microfilm and a minus green filter, it is possible to obtain negatives where the necrotic flecks appear as dark spots on a white leaf. The negatives are scanned in a TV-system and the size of the damaged fraction of the leaf is calculated by a microprosessor and is shown as a percentage of the leaf.

• Mortensen, E-mail: lm@mm.unknown
• Weisberg, E-mail: kw@mm.unknown

A monitoring program is planned for the terrestrial environment around industries in Sweden, which emit acid compounds and heavy metals. Directions for the County Government Boards are being prepared. The paper deals with the present pollution situation in Sweden, based on recent scientific results, the justifications for local monitoring, and the organizing of the monitoring including the parameters suggested.

Four examples from a case study at an oil power station illustrate reporting of the data and the difficulties in interpreting the results. The examples are the distribution of a lichen indicator, heavy metal content and phosphatase activity in the moor layer, soil respiration and tree growth.

• Westman, E-mail: lw@mm.unknown

Our preliminary findings indicate that the content of total sulphur and soluble fluorides in needles of the Scots pine (Pinus sylvestris L.) reflects the degree of air pollution with sulphur and fluorine compounds. A project for a map of air pollution in Poland, based on chemical analysis of Scots pine needles, is presented. Results of the total sulphur and soluble fluoride content in 2-year old needles from 15- to 25-year-old trees should yield a picture of air pollution with sulphur and fluorine compounds. The first stage will involve the preparation of a map of the area between the Warsaw and Plock agglomerations. This area will be divided into 10 squares with side dimension of 25 km each. Samples will be taken at 5 different sites in each square and also approximately every 5 km along a straight line between these towns.

• Molski, E-mail: bm@mm.unknown
• Bytnerowicz, E-mail: ab@mm.unknown
• Dmuchowski, E-mail: wd@mm.unknown

Air pollution injury to vegetation often occurs near a fertilizer factory in Central Sweden. The causing incidence often occurs in the winter and the symptoms appear when metabolism starts in the spring. Deciduous and coniferous trees and bushes were injured in the spring of 1979. Samples of Scots pine (Pinus sylvestris L.) needles were analysed for sulphur, total fluorine and nitrogen content, some of them for nitrate and ammonium. All the compounds showed elevated levels, clearly connected with the degree of exposure of the sampling site. The levels were higher in the spring than later in the growing season, indicating involvement in metabolism or leaching. None of the compounds was significantly in excess, although, elevated to an extent to indicate the cause of injury. Most probably the nitrogen compounds were involved. The problems encountered in tracing the causing pollutant, when injury appeared long after the incidence, might be easier solved with regularly used technical monitoring and bioindicator technique.

• Kvist, E-mail: kk@mm.unknown
• Jakobsson, E-mail: cj@mm.unknown

Grasses Agropyron spicatum Pursh, Lolium perenne L. (S23) and 2-year old Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) were exposed to low SO₂ concentrations under field conditions for approximately eleven weeks. SO₂ was released continuously via manifold delivery systems, and provided treatment mean concentrations of 0.007 (ambient air), 0.042, 0.106 and 0.198 ppm. The concentrations in each treatment were approximately log-normally distributed, with standard geometric deviations ranging from 2.58 to 3.24. In both grass species, 0.198 ppm SO₂ caused substantial reduction of total growth. In L. perenne, this was largely the result of impaired root growth, whereas both shoot and root growth of A. spicatum were reduced. 0.106 ppm SO₂ had no significant effect on A. spicatum growth, but reduced root growth of L. perenne. Growth of Douglas fir was reduced in each of the tree highest concentrations, with root growth being markedly diminished, particularly on trees which showed chlorotic and necrotic injury. However, in these trees the shoot and total leaf weights tended to increase at the highest SO₂ concentrations, suggesting that in these plants injury to leaves stimulated further shoot growth at the expense of root development.

• Runeckles, E-mail: vr@mm.unknown
• Palmer, E-mail: kp@mm.unknown
• Trabelsi, E-mail: ht@mm.unknown

Ultrastructure of mesophyll of second-year green needles of Picea abies (L.) H. Karst. and Pinus sylvestris (L.) has been studied in several polluted areas in Finland since 1976 (Soikkeli and Tuovinen 1979, Soikkeli 1981a). Four different types of injuries have been found. The types differ with the origin of the material:

1) In needles collected from areas pollute by S-communds the types with reduced grana and/or the with lightening of plastogobuli with simultaneous accumulation of lipid-like material are observed.

2) In needles expose to fluorides (alone or in addition to other pollutants) the type with swollen and/or that with curled thylakoids are found. Both of the latter have also stretched envelopes. In each type of the injury three stages of cell disruption have been described: slight-medium, severe and very severe. On the slight-medium stage the injuries are usually found only in chloroplasts. On severe stage other organelles show injuries, too. In very severe injury all cell organelles are badly disorganized or they disappear completely. The most abundant injuries are usually in needles collected after their second winter. The severity of cell injury depends on the closeness of emission source or on the measured concentration of SO₂.

• Soikkeli, E-mail: ss@mm.unknown

Information on input of acidifying compounds like SO₂ and NO_x is necessary to understand effects of acidification. The uptake on NO and NO2 respectively was studied on seedlings and shoots of Scots pine (Pinus sylvestris L.). Experiments were conducted both in laboratory (NO and NO₂ respectively) and in the field (NO₂) under light and dark conditions. In all three cases there was a linear relationship between the uptake rate and the NO_x-concentration. The uptake follows a diurnal pattern i.e. the uptake rate was strongly correlated with the stomatal movements. Uptake rates were converted to deposition rate and the results showed that field exposure with NO₂ gave the higher deposition rate.

• Skärby, E-mail: ls@mm.unknown
• Bengtson, E-mail: cb@mm.unknown
• Boström, E-mail: cb@mm.unknown
• Grennfelt, E-mail: pg@mm.unknown
• Troeng, E-mail: et@mm.unknown

The water in different parts of a plant forms a continuum throughout the plant body. This makes it possible to record changes in the water content as changes in thickness of any part of the plant. A leaf kept in darkness has been found to change its thickness to a sufficient degree for recordings of changes in transpiration from the rest of the plant. The rapidness of the changes makes it probable that they are mirroring the stomatal movements.

The method has been used for recording of influences of SO₂ as air pollutant. It has a couple of advantages over direct measurements of changes in transpiration. One is that the measurement can be used without enclosing the plant in a cuvette. Another is that possibly occurring effects on the hygrometer are eliminated. The method has until now mainly been used for wheat plants but also woody plants as Pinus and Salix have been tested.

• Rufelt, E-mail: hr@mm.unknown
• Wiese, E-mail: bw@mm.unknown

Natural forest tree populations are adapted to their natural environment. Forest tree species under northern conditions are at the edge of their range where the short growing season and the low winter temperatures are the two main factors limiting their ecological niche. Effects of air pollution on the ecological niche, designated as the environmental conditions that permit a population to survive permanently, are discussed according to G.E. Hutchinson’s concept of the ecological niche. Air pollution as an additional stress factor influences the ecological niche either by the direct influence as an additional dimension of the ecological niche or by interaction with the other dimensions. These interactions are especially important for low level long-term effects of air pollution which can result in reduced resistance to low winter temperature or, due to reduced net assimilation, reduced capability to survive the long period of winter dormancy. These effects influence the boundary of the ecological niche and reduce the area of the biotope of the respective species.

Within the remaining biotope genetic changes in forest tree species take place. Due to individual differences in exposure and susceptibility of trees to air pollution, higher and therefore more exposed trees as well as more susceptible trees will be reduced in reproduction or even be eliminated. This causes genetic changes in the tree population.

• Scholz, E-mail: fs@mm.unknown

The symposium of ’Air pollutants as additional stress factors under northern conditions’ was held in Oulu in Northern Finland during November 11–13, 1980. The symposium had four sessions: 1) the ecophysiology of air pollution effects and long-term risks of air pollution effects, 2) bioindication in forest ecosystems, 3) particle and metal problems, and 4) a general poster session mainly related to current research, and the results of the research programme on the dispersion and effects of air pollutants in forest environments financed by the Academy of Finland. Most of the posters and papers presented at the symposium have been included in the proceedings. The rest of the results presented are reviewed in research report of the programme and in the related scientific papers.

The PDF includes a summary in Finnish.

• Huttunen, E-mail: –

The development of the stomatal area wax structure of Scots pine (Pinus sylvestris L.) needles was studied in flushing needles with a scanning electron microscope. The needles were obtained from eleven Finnish plus tree progenies. The needles were taken from trees that were either nearly uninfected or heavily infected by Lophodermella sulcigena (Rostr.) Höhn.

No difference in the early developmental stages of stomatal vax structure were observed between the southern Finnish, central Finnish and northern Finnish progenies. The general structure differed in the stomatal cavity chamber size. The stomatal openings were larger in heavily infected trees than in healthy trees. This might have an influence on the mechanical penetration of the fungal hyphae.

The PDF includes a summary in Finnish.

• Jalkanen, E-mail: rj@mm.unknown
• Huttunen, E-mail: sh@mm.unknown
• Väisänen, E-mail: tv@mm.unknown

Light and economic FM-CW radar has been developed for controlling the bearing capacity of ice roads and landings on ice used for timber transportation and storage of timber in Finland. It was tested on natural ice and ice roads of three lakes in Southern Finland and one location on sea on the southren coast of Finland (a total of 166 observations). Ice thickness varied from 0 to 100 cm. Correlation coefficient between auger and radar measured ice thickness was r=0.99 and absolute error varied from -10 to +7 cm. The quality of ice had no influence, but by improving the interpretation of results, also the quality factors might be detected.

The PDF includes a summary in Finnish.

• Saarilahti, E-mail: ms@mm.unknown

Ethanolic sprays of GA₄ or GA₇ on 9-year old Scots pine (Pinus sylvestris L.) grafts, repeated four times during the shoot elongation period, resulted in a statistically significant increase in female flowering one year after the treatment. Of the two compounds, GA₄ seemed to be somewhat more efficient, yielding 47 female strobili/100 shoots vs. 36 and 6 strobili/100 shoots in GA₇ and control treatments respectively. The mixture of GA₄ and GA₇ compounds was also applied and seemed to have an effect intermediary to those of the pure compounds. However, due to the limited amounts of material, none of the differences between the gibberellins could be statistically confirmed. Male flowering frequencies were also too low to allow any firm conclusions, but the numerical results suggested that the purified gibberellins may promote male and female flowering in different ways.

The PDF includes a summary in Finnish.

• Luukkanen, E-mail: ol@mm.unknown

The objective of the investigation was to determine the differences between timber grown on a peatland before and after draining, in respect of compressive strength parallel to the grain, static bending strength and density. In addition, the characteristics of boundary zone between the wood formed before, and after the draining with wider growth rings was studied. 41 Scots pine (Pinus sylvestris L.) and 22 Norway spruce (Picea abies (L.) H. Karst.) trees were studied.

The compressive strength of pine usually decreased from the butt end upwards, but no trend was observed in spruce wood. In coniferous trees, wide-ringed wood formed subsequent to draining was slightly lighter than the close-ringed wood produced prior the draining. The density of pine as well as spruce increases as the width of the growth rings decrease up to a certain limit. The strength of the different kinds of wood seems to decrease from the butt end upwards.

In both species, the compressive strength parallel to the grain and the bending strength are lowest in such wood that contains exclusively wide-ringed wood formed subsequent to draining. Also, compressive and bending strength increase with decreasing width of the growth rings. The longitudinal shrinkage of compression wood in spruce was several times that of normal wood, and the bending strength was lower than that of normal wood particularly in spruce. The compressive strength parallel to the grain in dry condition was, however, higher than in normal wood both in pine and spruce.

The PDF includes a summary in English.

• Ollinmaa, E-mail: po@mm.unknown

The areas of soil cultivation in regeneration sites using different methods in 1976–1979 and the cultivation units in use in Finland in 1979 were studied by means of a questionnaire. Application of soil cultivation methods appears to have become strongly polarized: in Southern Finland disc plowing with wheel tractors are used, whilst in Northern Finland wing plowing with crawler tractors is the most popular method, each being practically the only alternative in the respective area.

The PDF includes a summary in English.

• Kaila, E-mail: sk@mm.unknown
• Päivänen, E-mail: jp@mm.unknown

Questionnaires were sent out to determine the volume of wood harvested from peatlands during 1978 and the harvesting problems encountered. In total there were 110 responses which accounted for 8 million m3 of wood harvested, of which 1.0 million m3 (14%) was harvested from peatlands. The largest proportion of wood harvested from peatlands was during the winter. Most of the respondents reportet that they wait for the soil frost to set before harvesting is started on peatlands. Respondents indicated a total of 263 machines bogging down in to the soil or, for 1978, a total for Finland of 750 to 1,000 machines.
The PDF includes a summary in English.

The PDF includes a summary in English.

• Saarilahti, E-mail: ms@mm.unknown

The crown structure and stem growth of Norway spruce (Picea abies (L.) H. Karst.) undergrowth was studied in relation to the prevailing light conditions and potential photosynthesis. Shading decreased the stem height growth more than the length increment of laterals, producing a plate-shaped crown in deep shade. Needles responded to shading by adopting a horizontal inclination in deep shade. The needles were wide and thin respectively in shade. In the open the needle cross-section was almost square. Stem radial growth and height growth were both affected by shading exhibiting a linear response to the prevailing light conditions and the potential photosynthesis. Light conditions under dominating trees were closely correlated with the basal area of the dominating trees.

The PDF includes a summary in Finnish.

• Greis, E-mail: ig@mm.unknown
• Kellomäki, E-mail: sk@mm.unknown

The present paper deals with the most important factors of peatland hydrology and the influence of forest drainage on the hydrology of peatland itself and its surroundings. It is compiled of six seminar papers written by students in the Department of Peatland Forestry in the University of Helsinki. Special attention is paid to the hydrological consequenses of the maintenance of drained areas. Also ways and measures to minimize the negative environmental effects of these treatments are discusses.

The PDF includes a summary in English.

• Heikurainen, E-mail: lh@mm.unknown
• Joensuu, E-mail: sj@mm.unknown

Needle damages, transpiration, photosynthesis and needle and stem height growth of Scots pine (Pinus sylvestris L.) seedlings treated with dilute sulphuric acid were studied. The acidity of the solution was pH 3. Application of a dilute solution of sulphuric acid equivalent to the normal amount of precipitation occurring during the growing season damaged the surface of two-year-old needles but not that of the current-year needles. A reduction in the photosynthetic rate of 10–30% was observed compared with the untreated seedlings. Transpiration of the seedlings was not affected by the treatment. Needle growth and stem height growth of the seedlings growing on a substrate representing poor sandy soil were reduced. Increased needle growth and stem height growth were characteristic for the seedlings growing on substrate representing fertile moraine.

The PDF includes a summary in English.

• Katainen, E-mail: hk@mm.unknown
• Kellomäki, E-mail: sk@mm.unknown

The effect of soil compaction on transpiration and height increment of Scots pine (Pinus sylvestris L.) seedlings following planting out were investigated in a small-scale pot experiment. Compacted and loosely-packed fine sand and fine-sand moraine were used as the planting substrates. The compacted soils used corresponded to the normal type of soil to be found in tilled forest soils in Finland. The effect of soil compaction on seedling transpiration during water stress was also studied in a separate experiment.

Seedlings planted in compact soil had a higher rate of transpiration than those in loosely-packed soil. The recovery in transpiration, which started halfway through the growing season, was faster, however, in the seedlings planted in loosely-packed soil. Under conditions of water stress, the seedlings planted in compact fine-sand moraine started to reduce the transpiration rate at higher soil moisture values than those planted in loosely-packed soil. No corresponding difference was observed for fine sand. Compaction was not found to affect the overall height growth, but it did at certain time during the growing season.

The PDF includes a summary in English.

• Smolander, E-mail: hs@mm.unknown
• Kostamo, E-mail: jk@mm.unknown
• Räsänen, E-mail: pr@mm.unknown

In Finland the first trade union in the field of forest work and timber floating was founded in 1946 and the first formal collective agreement was achieved in 1962. Information about the development of wage payments and work conditions (lodging and food) in forest work prior to the formal agreements was dispersed in a number of different sources, and is already partially in danger of being forgotten. The aim of this study was to bring together all available information concerning the matter in question.

The PDF includes a summary in English.

• Makkonen, E-mail: om@mm.unknown

The particle size distribution affects several properties of the soil, thus, the ability to define the texture type of the soil as accurately as possible in field conditions is essential. The soil particle size classification devised by Atterberg (1912) is used in Finnish forestry. The study is based on a small laboratory material. The correlation between some characteristics of the soil particle size distribution, field capacity and cation exchange capacity were determined.

The particle size characteristics such as the relative proportion of different particle sizes, average particle size (Md) and parameters depicting the degree of sorting were determined. The relative proportion of soil particles below 0.06 mm correlated best with both field capacity and cation exchange capacity. Similarly, the average particle size and the degree of sorting correlated well with the field capacity and the cation exchange capacity.

The use of sorting characteristics is not well-suited to the type of soil sample material containing a high proportion of particles of varying size as was used in this material. Such characteristics are probably more easily applicable to the fine sand and sand sediments which are predominant in Finnish forest soils. The most useful particle size distribution characteristics in soils having a great variation in particle sizes were the average particle size and the relative proportion of silt and clay. Thus, the nutrient and water status of the soil can be predicted to some extent by examining the percentage of silt and clay, average particle size and the degree of sorting.

The PDF includes a summary in English.

• Sepponen, E-mail: ps@mm.unknown

Ips acuminatus Gyll. (Coleoptera, Scolytidae) is a bark beetle that causes deep bluing in thin-barked Scots pine (Pinus sylvestris L.) pulpwood. It has been shown that this decreases pulp yield. The purpose of this study was to map the southern border of the distribution of Ips acuminatus in Finland. It was found that there have been changes in the distribution of this species during the last three decades. Ips acuminatus has now disappeared from southern Finland. On the basis of the sample plots (134 cutting areas) the southern border of this pest lies on the line running through the towns Vaasa–Seinäjoki–Äänekoski–Jyväskylä–Pieksämäki–Savonlinna–Punkaharju. A certain degree of localisation was observed in the occurrence of I. acuminatus in its distribution area, for instance, differences in its occurrence frequency in cutting areas and even in log and cutting residue piles in the sample cutting area.

It is considered that the most important reasons for these changes in distribution are the increase in logging and changes in the location of cutting sites, and resulting competition for breeding material for the increased population of bark beetles. Furthermore, the long-distance transport of unpeeled logs from the north across the present southern borders may, in the future, contribute to local changes in the southern distribution of Ips acuminatus.

The PDF includes a summary in English.

• Puukko, E-mail: kp@mm.unknown

In a locality in Southern Finland where the white-backed woodpecker, Dendrocopos leucotos (Bechst.), was previously breeding was found many conical borings excavated during the winter in young aspens (Populus tremula L.) on average 8.1 cm in diameter. Full-grown larvae of Saperda carcharias (L.) (Coleoptera, Cerambycidae) hibernated in pupal chambers constructed about 0.5 m above ground level. Below this chamber the larva has usually prepared an exit hole. After the larva has blocked itself in the pupating chamber it is easy to prey for the woodpecker during the whole winter.

There were usually 1–5 conical borings in the same trunk. The number of these borings did not correspond with the amounts of larvae eaten, since the woodpecker often made these borings in places from which it could not obtain a prey. The woodpeckers stopped excavating in those cases when the larvae in the galleries were dead. The exit holes and the conical borings occluded within a few years. The galleries within the tree will not heal and several years later a new larva may utilize them. In the wintering habitats of the white-backed woodpecker the availability of food could be improved by increasing the amount of S. sarcharias larvae. This is easily done by encouraging young aspens.

The PDF includes a summary in Finnish.

• Nuorteva, E-mail: mn@mm.unknown
• Patomäki, E-mail: jp@mm.unknown
• Saari, E-mail: ls@mm.unknown

The article deals with differences in economic growth in different countries and regions and with reasons for these differences. The central role in investments in economic growth and the mechanism of its differentiation are elucidated. The properties of forestry and the forest industries in equation or differentiating economic growth are considered. In the light of the theories of regional differentiation, the mere production of raw material in some region tends to increase differences in economic development if that raw material is processed in some other region – despite the fact that the level of income rises in both regions. It is therefore desirable that afforestation projects in the development countries are accompanied by the development of the forest industries.

The PDF includes a summary in Finnish.

• Riihinen, E-mail: pr@mm.unknown

The specific needle area of young Scots pine (Pinus sylvestris L.) showed a substantial within-tree and between-tree variation which was associated with the position of the tree and the position of the whorl as indicated by the prevailing crown and branch illumination. In suppressed trees the values of the specific needle area were three to four times those in dominating trees. A similar morphogenesis was discernible in comparison of the lower and the upper part of the crown. The mean specific needle area value for the whole stand was 184 cm²/g.

The PDF includes a summary in Finnish.

• Kellomäki, E-mail: sk@mm.unknown
• Oker-Blom, E-mail: po@mm.unknown

The anatomical variation of a lateral root was compared with that of the stem of the same tree at breast height by concentrating on the intrelationships of certain anatomical features in Betula pendula and B. pubescens. The results showed that root wood has several essential features of stem wood, such as gelatinous fibres, growth eccentricity, scalariform perforation plates in the vessels and pith flecks. However, some of the anatomical differences are significant. The differences between the species were more pronounced in the root than in the stem anatomy.

The PDF includes a summary in Finnish.

• Bhat, E-mail: kb@mm.unknown
• Kärkkäinen, E-mail: mk@mm.unknown

The aim of this study was to establish from the literature the purposes and for which aspen (Populus tremula L.) and related poplar species are used and can be used.  According to the literature, numerous Populus species can be utilized in the industry with success instead of light softwood species in addition to them. The main emphasis is in the growing of large-sized timber, and there is no clear trend to changing to the short-rotation forestry of poplar. However, the utilization of the good sprouting properties of Populus species will probably increase as this regeneration method is cheap.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

Ten trees of mountain birch (Betula tortuosa Ledeb, now Betula pubescens subsp. czerepanovii) with an average age of 39 years were sampled in northern Lapland in Finland. The average green density of wood was 589 kg/m³ and that of bark 941 kg/m³. The basic densities were 520 kg/m³ and 559 kg/m³, respectively. The basic density increased only little from the pith to the surface. In contrast, the number of bars in the perforation plates of the vessels increased considerably in the same direction. The average number of bars was 17.3.

The PDF includes a summary in Finnish.

• Bhat, E-mail: kb@mm.unknown
• Kärkkäinen, E-mail: mk@mm.unknown

The aim of the study was to find out the effect of the working place meetings on the increased cooperation between workers and supervisors, the improved work performance, the intensified use of machines and the improved job satisfaction. In the study loggers, forest machine operators and forement were interviewed. The results showed that the working place meeting is a useful means to realise the above-mentioned aims.

The PDF includes a summary in English.

• Kyttälä, E-mail: tk@mm.unknown

The share of stem, branch and needle growth was dependent on the within-stand light regime in a young Scots pine (Pinus sylvestris L.) stand. The share of needle growth increased at the expense of stem and branch growth in poor light conditions. In good light condition the share of branch wood increased substantially. The share of stem wood growth was greatest in moderate shading, emphasizing the role of an adequate stand density for growing high-quality timber. The basic density of the stem wood was considerably greater in suppressed trees than in dominating trees. The differences were related to the illumination of the crown system.

The PDF includes a summary in Finnish.

• Kellomäki, E-mail: sk@mm.unknown

The amount of volatile oil and monoterpene composition in Scots pine (Pinus sylvestris L.) needles were studied in trees growing near two factories and in the city of Kuopio, Central Finland. Trees in these locations are exposed principally to sulphur dioxide and fluoride emissions.

The amount of volatile oil increased with increasing injury class in the trees growing near the fertilizer factory. The amounts of volatile oil in trees near the pulp mill differed in the various injury classes. More oil was found in younger needles. The greatest differences in monoterpene composition were in the amounts of camphene, α-pinene, myrcene and tricyclene.

The PDF includes a summary in Finnish.

• Lehtiö, E-mail: hl@mm.unknown

The use and problems of the sucrose inversion method for the study of forest humus and soil are discussed. The method is based on the temperature dependence of sucrose inversion, changes in rotation angle being determined with a circle polarimeter. Average temperatures and thermal sums for forest humus in different forests in Finland were measured, using this method, for a period of ca. 100 days. The results are not considered definitive but are regarded rather as examples. Average temperatures were somewhat higher in the humus of dry and poor heath forests than in that of moist and herb-rich forests, with exceptions that could be explicable by topographic position.

The PDF includes a summary in English.

• Ohenoja, E-mail: eo@mm.unknown
• Pohjola, E-mail: lp@mm.unknown

This article is a book review on German textbook 'Forstinventur' by Fritz Zöher that handles forest inventory.

• Kilkki, E-mail: pk@mm.unknown

The purpose of this paper is to discuss the effect that the various measures by society have on bringing the level of the annual cut by private woodlot owners in line with the forestry policy goal of a long-term sustained yield of wood. The objectives and measures of forest policy in Sweden are described, as well as the central relations which explain the development in the logging policies of the private woodlot owners.

The goal of Swedish forestry policy has long been to safeguard a sustained yield of wood. This demand has successively been tightened, defined and detailed. The principle measure employed by the authorities to obtain the goal has been silvicultural legislation.

The author summarises that of all the means available of influencing the logging policy of private woodlot owners the most effective is silvicultural legislation. However, when viewed in an historical perspective, the legislation has not been able to significantly regulate the level of the annual cut. Nevertheless, at a time when there is a shortage of wood materials the legislation will undoubtedly exert a greater influence. Changes in forest taxation could prove to be an effective means in future of, for example, achieving an increase in the annual cut of private woodlot owners.

• Lönnstedt, E-mail: ll@mm.unknown

In dealing with the effectiveness of forest taxation reform as a means of economic policy, the paper starts by recalling certain objectives of taxation, as well as the effect on aggregate demand of taxation in general. The effect of forest taxation depends on such factors as (1) whether the woodland owner has a regular income from a source other than forestry; (2) the system of taxation (whether taxation of actual stumpage revenue or of area-based yield); (3) the progression of taxation; and (4) the woodland owner’s income level.

The problem is illustrated by an example taken from Finland, where forestry revenue is taxed on the basis of area-based yield. A shift to taxation of actual stumpage revenue, as is proposed, is assumed. The effectiveness of this change is studied in terms of how far the assumed change is consistent with the objectives of the national economy. It is assumed that a shift to taxation of actual stumpage revenue would cause a decline in roundwood supply. A sensitivity analysis is then applied to detect the effect on tax revenue and national income of the tax reform. It is likely that a 10% decrease in fellings would bring about a reduction of tax revenue which would not be compensated for by the more perfect exposure of forestry income to taxation brought by the reform. The effect on investment, production, employment, differences in individual and regional income, and on the international balance of payments also disfavour the suggested change.

• Riihinen, E-mail: pr@mm.unknown

The paper discusses certain aspects of the capital management of forest assets. These aspects are of importance when one wants to consider what means to use to influence the capital management on both small and big forest properties. When quantifying the effects of different uses of capital, one must necessarily have a scale. The rate of return is for this purpose the usual measure of profitability. We will first discuss the differences between nominal and real rate of return, and point out the assumptions which are often implicit in analyses of the profitability of investments in forestry. We will the discuss certain liquidity and risk aspects of capital investments in forestry, and at the end deal with certain consequences of taxation.

• Eid, E-mail: je@mm.unknown

Private forestry in the Federal Republic of Germany mainly consists of small holdings. Out of 534,000 proprietors 97% own 0.01–10.0 ha. This category covers 45% (1.4 million ha) of private woodlands in total. During the last decades cooperation has increased so that now about 50% of the small woodland is managed by voluntary cooperatives. The main aim of the cooperatives is the improvement of management by trying to overcome the disadvantages arising from small size, unfavourable location and splitting up, as well as from insufficient accessibility and other structural difficulties.

An economic analysis of forestry cooperatives was conducted by using a combination of model calculations and field investigations of 20 forestry cooperatives which represented different types of cooperation in all regions of the country. The theoretical calculations showed the amplitude of efficiency improvement in small holdings by means of cooperation. It was shown that there were relatively poor results in the beginning and success could be achieved only in the long-term view by improving quality of stands. According to the analysis of the 20 cooperatives, the possible annual cutting rate was 4.1 m³/ha, but the actual cutting rate reached only 3.7 m³/ha. Aims of the cooperatives manly concerned coordination of production, mechanization, material acquisition and timber sales. The subsidization of forestry cooperatives proved, in general, to be insufficient. A discussion of different ways of subsidization showed that from the microeconomic point of view direct product subsidies of timber production may be more favourable than area-based grants.

• Brabänder, E-mail: hb@mm.unknown

In Japan, there are 2,990,000 forest owners within the scope of Forest Cooperatives, 60% of which are members of forest cooperatives. These are the largest functional organizations concerning private forests in Japan. The majority of members are small woodland owners with less than 20 ha per person, and 90% of the members are of agricultural cooperatives. The variety of memberships makes it difficult for cooperatives to strengthen its solidarity. The article describes the legislation concerning cooperatives in Japan, characteristics of business, reforestation and logging made by the forest cooperatives, and reorganization of the forest workers of the cooperatives.

Steady expansion of the main activities of the Forest Cooperatives, i.e. logging, marketing and reforestation, has been seen during the past 20 years. Logging and marketing have been taken over from the timber-dealers, and reforestation has been expanded by the Forest Cooperatives on the members’ behalf.

• Tanaka, E-mail: st@mm.unknown

A study to determine the effectiveness of private forestry assistance programs in Ontario, Quebec, New Brunswick and Nova Scotia in Canada was conducted among three complementary groups of individuals concerned with the private forest resource. Rural residents, members of woodlot owner associations and extension foresters in the four provinces were surveyed using three different, bilingual questionnaires. The majority of rural residences do not use forestry assistance programs. 45% of the woodlot association members responding used one or more of the several available programs. 54% of these users had a high regard for the assistance provided. Extension foresters felt that the objectives of their respective assistance programs were being met with available resources but performance could be bettered with more staff, increased budgets and an improvement in communications. This was a first attempt to evaluate private forestry assistance programs in a Canadian context

• Madigan, E-mail: gm@mm.unknown
• Jones, E-mail: aj@mm.unknown

The purpose of the present study is to explore the applicability of some methodological approaches to empirical policy analysis in evaluating the effectiveness of public forest policy. From the perspective of effectiveness analysis we can distinguish in forest policy, aiming at the promotion of timber production, two principal objective levels in forestry: the quantity of silvicultural investments and their allocation and the quantity (sufficiency) together with the structure of timber supply. This paper is restricted to the exploration of the effect of forest policy measures directed to silvicultural investments in private forestry. First, the effects of state subsidies in silvicultural investments are analysed. The analysis is macro analysis of quantitative forest policy means, in which aggregated time series data are used as study material. Second, an attempt is made to provide a causal interpretation of the impacts of qualitative forest policy means at the woodlot level. This micro analysis utilizes an approach characteristic to the behavioural sciences.

It is concluded that like quantitative forest policy means the qualitative means, coupled with the activities of the forest promotion organizations, play a significant role in attaining the timber production goals. Of these, the professional advice given by forestry experts, has a direct effect on silvicultural activities. Extension and training activities have an indirect effect by increasing the willingness of forest owners to employ experts on their woodlots.

• Tikkanen, E-mail: it@mm.unknown

The need for the planning and analysing of public policy has increased in economic and social policy, along with the expansion of the public sector, i.e. as the number of aims of the policy has increased and the objects of it have become more versatile, the objects of allocation have likewise been multiplied. In addition, the significance of planning a public forest policy has been emphasized by many economic and social changes in forestry and the timber economy.

The purpose of the present paper is to outline a general frame of reference for empirical policy analysis, upon which the effectiveness analysis of forest policy is also based. The approach serves as a methodological frame for the empirical analysis, presented in the following paper of this issue of Silva Fennica, in which econometric methods are applied to the examination of the effect of public forest policy.

• Tikkanen, E-mail: it@mm.unknown

Research concerning the forest owners’ behaviour plays an important role in the evaluation of the effectiveness of forest policy on small woodlots. This is because the effects of forest policy measures on forestry are indirect and channelled through the behaviour of a forest owner. In this paper some basic concepts and methodological problems of forest owner studies are discussed. First, the concepts ’forest owner’ and ’forestry behaviour’ are defined on the basis of general sociological term, social role. Second, the problem of explanation and the selection of the explanatory model in forest owner studies is discussed. In this connection the heuristic nature of the selection of the explanatory model is underlined. It is pointed out that the proper explanatory mode in forest owner studies is decisively dependent on the objectives of the study or on the kind of information that will be obtained by the study. In such studies that intend to serve the planning and implementation of forest policy, it seems necessary to aim at causal explanations, and to analyse the general determinants and factors that can be manipulated in forest owners’ behaviour.

• Järveläinen, E-mail: vj@mm.unknown

This collection of nine articles considers theoretical and methodological aspects as well as empirical research problems associated with the elevation of the effectiveness of forest policy measures on small woodlands. The papers presented concern aspects of research strategy in studying forest owner’s behaviour (Järveläinen) and causality as a conceptual frame for forest policy analysis (Tikkanen); an econometric analysis on the effects of public forest policy in Finland (Tikkanen); a survey concerning the private forest owners and the forestry assistance program in Eastern Canada (Madigan and Jones); the forestry co-operative as a policy measure (Tanaka) and the subsidies and efficiency in forestry co-operatives (Brabänder); the forest as a capital asset (Eid) and effectiveness of forest taxation reform as a means of economic policy (Riihinen); and the influence of Swedish forestry policy on the annual cut of private woodlot owners (Lönnstedt).

The PDF includes a summary in Finnish.

• Järveläinen, E-mail: –

Downy birch (Betula pubescens Ehrh.) trees growing on a drained peatland were cut during dormancy. The properties of the one-year old shoots produced by the stumps were measured in the autumn after one growing season. The one-year old willow shoots (a mixture of Salix phylicifolia L., S. pentandra L. and S. caprea L.) were collected from an abandoned field.

The basic density of unbarked shoots was 443 kg/m³ for birch and 346 kg/m³ for willow. The basic density of the bark was much higher than that of the wood. The effect of shoot length on the properties was small with the exception of cellular proportions. The fibre percentage increased and vessel percentage decreased with increasing shoot length.

The PDF includes a summary in Finnish.

• Bhat, E-mail: kb@mm.unknown
• Ferm, E-mail: af@mm.unknown
• Kärkkäinen, E-mail: mk@mm.unknown

Length variation of fibres and vessels was studied in the branches, stems and roots of Betula pendula Roth and B. pubescense Ehrh. The cells were significantly shorter in the branches and roots than in the stems. There was no significant difference in the cell length between the upper and lower radii of the branches and roots. The length increased from the pith to the surface and decreased in the branches and stems from the base onwards. In the roots the length increased in that direction. The differences between the tree species were small although the cells of B. pubescens were a little longer.

The PDF includes a summary in Finnish.

• Bhat, E-mail: kb@mm.unknown
• Kärkkäinen, E-mail: mk@mm.unknown

Variation of cellular proportion within the same growth rings counted from the pith of the stems and branches in four trees of Betula pendula Roth was studied. The fibre percentage decreased from breast height to the crown and then increased in the branches. The reverse trend was found in the percentage of vessels and parenchyma, although the latter varied relatively little. No statistically significant differences were found in the percentages of fibres, vessels and rays within the same growth rings counted from the pith between the stems and branches. In both the stem and the branches, the proportion of fibres increased and that of vessels and rays decreased from the pith to the surface. Even crown formed wood differed from that of stem formed. 

The PDF includes a summary in Finnish. 

• Bhat, E-mail: kb@mm.unknown
• Kärkkäinen, E-mail: mk@mm.unknown