The term Fennoscandia is used to denote Finland and the Scandinavian peninsula, which comprises Norway and Sweden and sometimes also neigh­ bouring districts of the USSR. The western part of the Scandinavian peninsula is mountainous with peaks mostly within the range 1000-2000 m above sea level. Permafrost is not usually found in the southern districts of these alpine zones, but occurs in the northeastern part of Fennoscandia in mire, even at a low elevation. If tundra is defined as areas of permafrost, only very limited regions of Fennoscandia could be included. However, in the present volumes, we have used the word tundra in a broader sense as approximating areas with mean annual air 0 temperature below 0 C at meteorological standard height (1.5-2 m); it is often used in this sense in North America. This usage allows all alpine zones to be included, along with the subalpine birch zone and certain open subarctic woodland ("forest tundra" in Russian usage).

Inhalt

1. Site Description.- Description of Fennoscandian Tundra Ecosystems.- 2. Abiotic Variables.- Soils of Fennoscandian IBP Tundra Ecosystems.- Climate and Hydrology of Some Fennoscandian Tundra Ecosystems.- 3. Primary Producers.- 3.1. Plant Structure.- Flora and Plant Sociology in Fennoscandian Tundra Areas.- Survey of the Main Plant Communities on Hardangervidda.- Vegetation Mapping at Hardangervidda.- Dispersal and Primary Establishment of Vegetation.- Comparison of Plant Structure on Grazed and Ungrazed Tundra Meadows.- Plant Phenology of Fennoscandian Tundra Areas.- Measurement of Leaf Areas and Leaf Angles of Plants at Hardangervidda, Norway.- 3.2. Biomass and Production.- Plant Biomass and Primary Production of Fennoscandian Subarctic and Subalpine Forests and of Alpine Willow and Heath Ecosystems.- Primary Productivity of Alpine Meadow Communities.- Growth in Populations of Andromeda polifolia on a Subarctic Mire.- 3.3. Plant Processes.- Weight Increase of Some Lichens as Related to Carbon Dioxide Exchange and Thallus Moisture.- CO2 Exchange and Growth of Rhacomitrium lanuginosum and Dicranum elongatum.- On the Effect of Continuous Light on Photosynthesis in Mosses.- Acclimatization Effect in Photosynthesis and Respiration.- CO2 Exchange in Norwegian Tundra Plants Studied by Infrared Gas Analyzer Technique.- Photosynthesis and Respiration of Plants Studied by Field Technique at Hardangervidda, Norway.- The Seasonal Pattern of Photosynthesis of Some Vascular Plants on a Subarctic Mire.- Energy Content and Use of Solar Radiation of Fennoscandian Tundra Plants.- Distribution of 14C Photosynthates in Norwegian Alpine Plants.- Pigment Structure of Vascular Plants, Mosses, and Lichens at Hardangervidda, Norway.- 4. Decomposers.- Decomposition, Microbiology, and Ecosystem Analysis.- Biomass and Production of Soil and Litter Fungi at Scandinavian Tundra Sites.- Microfungal Populations of the Abisko Area, Northern Sweden.- Bacterial Populations of Some Fennoscandian Tundra Soils.- Comparisons ofDecomposition Rates Measured by Means of Cellulose.- Plant Litter Decomposition at Fennoscandian Tundra Sites.- Carbon Losses from Tundra Soils.- 5. Nutrient Cycling.- Nitrogen Fixation in Lichens at Kevo, North-Finland.- Nitrogen Fixation by Bacteria and FreeLiving Blue-Green Algae in Tundra Areas.- Mineral Content of Tundra and Forest Tundra Plants in Fennoscandia.- Analysis of Precipitation at Fennoscandian Tundra Sites.- Organic Compounds in Alpine Plants.- The Input and Significance of Particulate Terrestrial Organic Carbon in a Subalpine Freshwater Ecosystem.