Current issue: 56(4)
Under compilation: 57(1)
Dormant needles from 129 Norway spruce (Picea abies (L.) H. Karst.) trees from the 2nd and 3rd topmost whorls were collected from spruce stands locating fairly close to each other. Tree height varied from 8 to 25 metres. Trees with and without visual potassium deficiency symptoms in needles were selected and analysed for nitrogen, phosphorus, potassium, magnesium, boron, copper, zinc, and 3 free polyamines putrescine, spermine and spermidine.
The concentrations of all the analysed nutrients ranged from deficient to satisfactory levels. Free putrescine, spermidine and spermine concentrations in the current needles had a wide variation between the trees. Spermidine had a positive and spermine a negative correlation with potassium. Putrescine had a strong negative correlation with potassium with statistically significant increase in putrescine starting at potassium concentrations below 5.4 mg/g dry weight. The regression between putrescine and potassium changed from a linear to a non-linear form at the potassium concentration of 4.2–4.6 mg/g dry weight representing a severe K deficiency limit. The corresponding K/P ratio was 2.6–2.7. Extremely low phosphorus concentrations (P < 1.0 mg/g) lowered putrescine concentrations, but otherwise the relationships between putrescine, spermidine or spermine and potassium concentrations were unaffected by tree nutrition. At adequate potassium levels the putrescine concentrations were only slightly lower in trees taller than 20 metres than in trees of 8–16 metres height. The results show that the needle putrescine concentration can be used quite reliably for describing potassium nutrition of Norway spruce in varying nutritional and tree size conditions.
Willows (Salix phylicifolia) were grown for four months in organic rich soil at four nutrient levels (fertilization with a micronutrient-macronutrient mixture of 0, 100, 500 and 1,000 kg ha-1 per month) and four CO2 concentrations (300, 500, 700 and 1,000 ppm). Nitrogen and phosphorus concentration of the willows were reduced at CO2 enhancement, the decrease being larger in the leave and roots than in the stems. Nitrogen content of the willows plus extractable nitrate-N in the soil coincided well with the doses of nitrogen supplied, but the corresponding sum of phosphorus in the plants and soil were smaller. The total nitrogen content of willows grown in unfertilized soil was nearly two times higher than the sum of the extractable nitrate-N in soil and N content of the cutting at the beginning of the experiment. The contents of nitrogen and phosphorus of the unfertilized willows were independent of CO2 concentration, suggesting that CO2 concentration did not affect through increased mineralization the availability of those nutrients to the willows.
Energy intake of ten lumberjacks in Eastern Finland was estimated by using 24-hour recall. In addition, serum cholesterol and triglycerides were analysed in different lipoprotein fractions. Average energy intake was according to present recommendations in Finland, although there was great individual variation. Serum triglycerides were in the normal range. Five lumberjacks’ total cholesterol concentration was somewhat increased. Average HDL concentration was clearly greater than in men of the same age.
The PDF includes a summary in English.
The Nordic working group for forest fertilization is a group of research workers from the Nordic countries Denmark, Finland, Norway and Sweden, which has been working on plant nutrition questions and forest amelioration problems. The group has met annually to discuss current problems, hitherto mostly concerning forest fertilization. In 1976 the question of future working forms came up, and the group decided to arrange a symposium on the subject Nutrient cycle in tree stands in 1977.
This symposium took place in Harjavalta and Ikalis in Finland from the 29th of August to 1st of September 1977. During the symposium 12 papers were presented, which are published in the following, either in full or as summaries of a given lecture. Part of the lectures are in English and part in Swedish.
The paper includes the following titles:
A bioelement budget of an old Scots pine forest in Central Sweden
Mobilization of plant nutrients in a Scots pine forest Mor in Central Sweden
Accumulation of organic matter and nitrogen on sand dunes following sand fixation and planting of dwarf mountain pine
Sambandet mellan torvmarkstyp och yttorvens näringshalt
Changes in the amounts of inorganic nutrients in the soil after clear-felling
Plant nutrient balance in decoration greenery cultivation
The effect of forest fertilization on primary production and nutrient cycling in the forest ecosystem
Förändringar i humuslagret efter skogsgödling
Balanserad näringsupptagning och behovet av gödsling i trädbestånd på näringsfattiga torvmarker
Of fertilization on nutrient contents in needles and litter fall of Scots pine on dwarf shrub pine swamp
Micro-nutrient deficiencies cause growth disturbances in trees
Tallarnas växtstörningar, markens näringsbalans och micronäringsbrist
Increase in the elk (Alces alces L.) population and the problems of its grazing has called for detailed research. The present study concentrated on three observation areas representing northern, western and eastern parts of Finland. There were 28 field observers watching 68 elks.
Earlier investigations in Finland indicate that aspen (Populus tremula L.) is the staple diet of elk. This study reached different conclusions, probably largely because of aspen is gradually becoming an increasingly rare tree species in Finland. According to this study, the principal food of elk in the winter is willow (Salix sp.). In the whole country, willow accounts for about 70% of elk’s nutrition. In the Far North the percentage is approx. 90. Of the other tree species, the order of preference is: aspen, Scots pine, mountain ash, juniper and birch. In addition, in Western Finland where snow is less deep, lingonberry and blueberry shrubs are on the menu. Beard moss on the spruce was frequently eaten locally. Elk seems to have eaten mainly the last annual shoot of trees and bushes. In few cases it has gnawed the bark of Scots pine, aspen and willow. Elk consumes in average 340 twigs or terminal shoots per day in the winter. This corresponds to about 1.8 kg of food.
The problem of elks damaging Scots pine seedlings has been observed in Western Finland, were the elk population is higher. The article suggests that suitable feeding places would be left for elk in places that are unsuitable for agriculture or forestry. Leaving, for instance, birch seedlings in Scots pine stands has been noticed to attract elks and to increase the damage to pine.
The article includes an abstract in English and a summary in Swedish.
The effects of wood ash fertilisation on tree nutrition and growth on forested peatlands has been studied using loose ash, but in practice, ash fertilisation is done almost exclusively with granulated ash. In this study, the effects of granulated ash and loose ash (both 5 Mg ha–1) on the growth and nutrition of Scots pine (Pinus sylvestris L.) stands were compared between a nitrogen-poor and a nitrogen-rich site over 15 years. On the nitrogen-rich site, wood ash application was also compared with commercial PK fertilisation. On the nitrogen-rich site, mean stand volume growth increase over unfertilised control treatment during the 15 year study period using granulated ash and commercial PK fertiliser was of the same magnitude (on average, 2.2–2.3 m3 ha–1 a–1). However, when loose ash was used growth increase over control was higher (3.7 m3 ha–1 a–1). On the nitrogen-poor site, the mean growth increase gained by loose or granulated ash (1.4–1.5 m3 ha–1 a–1) over the unfertilised control treatment was not significant. Fertilisation with loose ash or PK increased foliar P, K and B concentrations already in the first or second growing season, following fertilisation on both sites. Granulated ash increased foliar P concentrations on the nitrogen-rich site less than loose ash. After an initial increase, foliar P, K and B concentrations decreased at the end of study period. On the nitrogen-poor site, foliar P concentrations were below the deficiency limit by the end of the study period.
In the boreal forest of eastern Canada, a large proportion of black spruce (Picea mariana [Mill.] Britton, Sterns & Poggenb.) stands are affected by paludification. Edaphic conditions that are created by paludification processes, including an abundance of microsites with high moisture and low nutrient contents, hinder forest regeneration. Disturbance of paludified sites by mechanical soil preparation (MSP) reduces organic layer thickness, while generating a range of substrates for regeneration establishment. Yet, little information is available regarding the effects of these substrates on tree growth. Our objective was to determine the effect of organic, mineral and organo-mineral substrates that are created following MSP of a paludified site on the growth and root development of black spruce seedlings in a semi-controlled environment. We demonstrated that substrate exerted a significant effect on seedling growth and foliar concentrations of N, P and K. Increase in height and diameter were respectively greatest on clay (mineral) and mesic substrates. Substrate effects did not affect total biomass increases or final root biomass. Foliar nutrients (N, P, K) were relatively high in seedlings that were established on mesic substrates and relatively low for those established on clay substrates. To ensure successful seedling establishment, we recommend the application of MSP techniques that expose organic-mesic substrates on sites that are susceptible to paludification.
Yellowhorn (Xanthoceras sorbifolium Bunge) has been widely planted for biodiesel production in China, but has frequently shown poor field performance. Container-grown yellowhorn seedlings originating from three Chinese provenances, Wengniute Qi (WQ), Alukeerqin Qi (AQ), and Shanxian (SX), were fertilized with slow-release fertilizer (SRF) at 40, 80, 120, 160 or 200 mg N seedling–1. Tree growth, survival and nutrient content were measured after one year’s growth in a greenhouse followed by two years in a field site. Plants from AQ and SX tended to have higher stem and root P contents in the nursery. Higher rates of SRF increased root N, and stem and root P contents. After one year in the nursery, there were a number of interactions between provenance and SRF for plant growth responses and nutrient content in the nursery, however after two years of additional growth in the field, plants from the different provenances generally responded similarly to applied SRF in the nursery, with few interactions. Final plant height was approximately 10% lower in trees from provenance SX but was not affected by application of SRF. Conversely, final trunk diameter and stem and root biomass were unaffected by provenance but increased with higher rates of applied SRF. Our results indicate that application of SRF may be a useful tool to nutrient load yellowhorn in the nursery and facilitate transplanting performance in the field. Overall, optimal nursery and field performance of yellowhorn were observed in provenance AQ at 120–200 mg N seedling–1 SRF. We suggest that growers consider a wider range of yellowhorn provenances and SRF rates (above 200 mg N seedling–1) to yield even better growth response.