Kari Heliövaara

Contents 1. Introduction to Physical, Physiological and Causal Forest Ecology 2. The Approach to Construct and Test the Theory of Forest Ecology 3. Environmental Factors 3.1 Properties of Environment 3.2 Diurnal Cycle in Environmental Factors 3.3 Annual Cycle of Environmental Factors 3.4 Environmental Factors Inside a Canopy Annex: Annual Cycle of Radiation 4. Processes in Living Structures 4.1 Structure of Vegetation 4.1.1 Cellular Level 4.1.2 Tissues 4.1.3 Organs 4.1.4 Individual 4.1.5 Stand 4.2 Vegetation Processes 4.2.1 Annual Cycle of Processes 4.2.2 Photosynthesis and Transpiration 4.2.3 Respiration 4.2.4 Senescence 4.2.5 Uptake of Water and Nutrients by Roots 4.2.6 Bud Burst Phenology 4.2.7 Shoot Elongation 4.2.8 Nox Exchange of Needles 4.3 Structure of Forest Soil 4.3.1 Mineral Soil 4.3.2 Soil Organic Matter 4.3.3 Soil Structure, Water and Air 4.3.4 Soil Organisms 4.3.5 Soil Horizons and Distribution 4.4 Processes in Soil 4.4.1 General Considerations About Processes in Soil 4.4.2 Ion Exchange and Retention 4.4.3 Decomposition of Soil Organic Matter 4.4.4 Nitrogen Processes in Soil 4.5 Forest Animals Annex: Transport 5. Fluxes of Carbon, Water and Nutrients 5.1 Water and Sugar Transport in Trees 5.1.1 Introduction 5.1.2 Upward Flow of Water in Xylem 5.1.3 Assimilate Transport in Phloem 5.2 Water Dynamics in Forest Soil 5.3 Carbon Dioxide in Soil 5.4 Co2, Water Vapour and Energy Fluxes Between Forest Ecosystem and Atmosphere 5.4.1 Structural, Metabolic and Physical Background of the Fluxes 5.4.2 Processes Generating Co2 and Water Vapour Fluxes Between Ecosystems and the Atmosphere 5.4.3 Co2 and Water Vapour Fluxes Between Forest Ecosystem and the Atmosphere 5.4.4 Energy Fluxes Within and Over Forest 5.5 Statistical Analysis of the Daily Photosynthetic Production of Coniferous Canopies Consistent with Process Knowledge 5.6 Annual Energy, Carbon, Nitrogen, Water and Ion Fluxes and Amounts at SMEAR II 6. Structural Regularities in Trees 6.1 Functional Basis of the Regularities in Tree Structure 6.2 Tree Structure as Balanced Water Transport System 6.3 Nitrogen Concentration in Leaves, Wood and Fine Roots in Scots Pine 7. Dynamics of Carbon and Nitrogen Fluxes and Pools in Forest Ecosystem 7.1 Structural, Metabolic and Evolutionary Basis of Ecosystem Development 7.2 Quantification of Carbon and Nitrogen Dynamics: Ecosystem Model Microforest 7.2.1 Trees 7.2.2 Growth of Ground Vegetation 7.2.3 Carbon and Nitrogen Dynamics in Soil 7.2.4 Connections Between Trees, Ground Vegetation and Soil 7.3 Carbon and Nitrogen Dynamics in Forest Ecosystem Around SMEAR II 7.3.1 Field Measurements 7.3.2 Parameter Values 7.3.3 Simulation of the Forest Ecosystem Around SMEAR II 7.3.4 Evaluation of the Simulations At SMEAR II 7.4 Test of Microforest Against Data On Tree Growth 7.4.1 First Test of Microforest 7.4.2 Second Test of Microforest Annex: List of Parameter Values and Units in MicroForest Annex: List of Variables in MicroForest Model 8. How to Utilize The Knowledge of Causal Responses? 8.1 Applications to Forestry 8.1.1 The Effect Thinnings On Wood Production 8.1.2 The Effect of Whole Tree Harvesting On The Site Fertility 8.1.3 The Effect of Nitrogen Deposition On Forest Production 8.2 Climate Change and Forests 8.2.1 Physical Background of Climate Change 8.2.2 Mechanisms of Climate Change 8.2.3 Observed and Projected Changes in Climate 8.2.4 Responses of Forest Ecosystems to Climate Change 8.2.5 Response of Boreal Forests to Climate Change 8.2.6 Feedback from Forests to Climate Change 9. Station for Measuring Ecosystem-Atmosphere Relations - SMEAR 10. The Physical and Physiological Theory of Forest Ecology and its Evaluation Index

Morphological variation in the pine bark bug Aradus cinnarnomeus Panzer was studied by making 43 metric measurements of the head, thorax and abdomen of adult males and 40 of the females (n = 1884). The amount of individual variation in males and females was studied both in pooled bug material and separately in two parapatric alternate-year cohorts, i.e. in the Finnish eastern even-year and the western odd-year reproducing populations. The first three dimensions in a principal components analysis accounted for 36% of the variation present in males in the pooled data and for 43% of the variation in females, respectively. There appeared to be different trends in individual variation within the western odd-year cohort and within the eastern even-year cohort. The first principal component describes the general size of the bug in all analyses, while the second and third components correlate best with different measurements depending on the sex and the cohort examined.

s  Taking different forests in Aershan of Inner Mongolia as sample plots, diversity and dominant species of arthropods were studied. The results show that two classes, 17 orders, 68 families, 130 species and 3742 individuals were identified and 92.31% of total species appeared in natural forests, and 75.38% of total species appeared in plantations. The orders of Lepidoptera, Coleoptera, Diptera and

Threatened species have received a lot of attention in northern Europe, while little is known about the biogeography of biodiversity. We investigated the species diversity of Saltatoria, Sesiidae, Buprestidae and Cerambycidae to try to discover hot-spots for conservation among the 101 biogeographical provinces of Denmark, Norway, Sweden, Finland and the adjacent parts of Russia using presence/absence data from the literature. In each insect group examined the number of species was generally highest in the southern provinces, declining to the north and northwest. Critical fauna analysis showed that 70-80% of the species were recorded from the most species-rich province and 3-11 provinces covered the whole fauna. The use of different rarity indices to compensate biases caused by unequal collecting gave variable results and indicated that there are considerable differences between insect groups. No relation was found between species richness and the geographical size of the province. The rarity values were more or less indifferent as regards longitude and even the relation with latitude was relatively indistinct. There was a clear difference between the ranking of provinces on the basis of the number of threatened species and the indices based on species richness or (biogeographical) rarity.

The concentrations of copper, iron, nickel and cadmium were studied in cocoons of four pine sawfly species, viz. Gilpinia virens, G. frutetorum, Microdiprion pallipes and Neodiprion sertifer. Larvae were reared in the laboratory on needles of Scots pine collected along a pollution gradient around a copper smelter in SW Finland. Heavy metal concentrations in all the species and needles decreased with increasing distance from the pollution source in accordance with linear regression models. Metal levels were highest in M. pallipes and lowest in G. virens, being only about one half to one quarter of those in M. pallipes. Concentrations of copper, iron and nickel in the insects were lower than in their food. Cadmium bioaccumulated in N. sertifer, G. frutetorum and, especially, in M. pallipes. The differences in these closely related pine defoliators are comparable to those between different trophic levels or species with entirely different feeding characteristics.

ABSTRACT Forests with single tree species are hypothesized to be more susceptible to pest outbreaks than mixed forests. Population densities of two insect species, Ips subelongatus Motschulsky and Lymantria dispar L., with different dietary spectra were investigated in pure and mixed stands using window and light traps in Aershan forestry bureau, northeastern China in 2009. I. subelongatus is a monophagous pest of Larix gmelinii (Rupr.) Rupr. in the study area, while L. dispar is a highly polyphagous pest species feeding on both coniferous and deciduous tree species. The individual number and dominance index of the two indicator species were investigated and analyzed in 21 forest stands in a thinning-caused gradient of larch-birch mixture ranging from pure larch stands to pure birch stands (seven types in the present study). The results showed that the number of individuals of I. subelongatus was significantly related to the proportion of larch trees, i.e. the number of individuals decreased with the rising birch ratio in the canopy layer. Similar decrease was observed in the dominance index of I. subelongatus. However, no significantly obvious effects of canopy mixture on the individual number or dominance index were observed in L. dispar.

Morphological variation in the pine bark bug Aradus cinnarnomeus Panzer was studied by making 43 metric measurements of the head, thorax and abdomen of adult males and 40 of the females (n = 1884). The amount of individual variation in males and females was studied both in pooled bug material and separately in two parapatric alternate-year cohorts, i.e. in the Finnish eastern even-year and the western odd-year reproducing populations. The first three dimensions in a principal components analysis accounted for 36% of the variation present in males in the pooled data and for 43% of the variation in females, respectively. There appeared to be different trends in individual variation within the western odd-year cohort and within the eastern even-year cohort. The first principal component describes the general size of the bug in all analyses, while the second and third components correlate best with different measurements depending on the sex and the cohort examined.

Parthenogenetically produced male larvae of Gilpinia frutetorum, G. virens and Microdiprion pallipes, and female and male larvae of Neodiprion sertifer were reared on needles of Scots pine affected by industrial air pollutants in Finland. Needles were collected at different distances from a distinctive emission source along two 9‐km‐long transects, and at independent control plots. Cocoon weight, length and width correlated with the distance from the emission source being smallest near it. Elemental composition of the pine needles and the effect of the ovipositing female covered 10–25% of the variation in cocoon weight. Heavy metal levels played a major role in M. pallipes and N. sertifer, and phosphorus in G. virens. The size of G. frutetorum cocoons was associated only with the female the progeny of which they were.ZusammenfassungUntersuchungen zur Reduktion der Kokongröße von Buschhornblattwespen (Hym., Diprionidae) bei Zucht auf schadstoffbelasteten KiefernParthenogenetisch erzeugte männliche Larven von Gilpinia frutetorum, Microdiprion pallipes und G. virens sowie weibliche und männliche Larven von Neodiprion sertifer wurden an Nadeln der durch industrielle Luftverunreinigungen belasteten Kiefern im Labor gezüchtet. Die Zweige wurden in zwei 9 km langen Linienprobeflächen in unterschiedlichen Abständen von der Emissionsquelle sowie in zwei getrennten Kontrollgebieten entnommen. Gewicht, Länge und Breite der Kokons korrelierten mit dem Abstand von der Emissionsquelle und waren in unmittelbarer Nähe von ihr am kleinsten. Die Grundstoffzusammensetzung der Kiefernnadeln und der Einfluß des eierablegenden Weibchens erklärten 10–25 % der Größenvariation der Kokons. Die Schwermetalle hatten einen deutlichen Einfluß auf die Kokongröße von M. pallipes und N. sertifer und Phosphor auf die Kokongröße von G. virens. Die Kokongröße von G. frutetorum wurde nur von den Muttertieren beeinflußt.