Current issue: 53(1)
Under compilation: 53(2)
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
The paper deals with variation in the nitrogen, phosphorus, potassium, calcium and magnesium content of vegetation and soil of young Scots pine (Pinus sylvestris L.) stand of Vaccinium site type situated in Central Finland. The material consists of sequential samples representing soil, ground vegetation and trees taken during summer 1974.
The amount of soluble nutrients in the humus layer decreased in June when maximum growth of trees and dwarf shrubs occurred. The nutrient content of this layer subsequently began to increase towards the end of the growing period.
The variation in the nutrient content of the bottom and ground layers followed a similar pattern. Nitrogen content increases at the beginning of the summer. After this phase it started to decrease and reached its lowest values by the end of growing period. Phosphorus and potassium content increased throughout the growing period.
The nutrient content of the needles and wood were positively correlated with tree height and negatively with the age of material. The highest values for the nutrient content were for new cells.
The PDF includes a summary in English.