Management of Nutrition in Forests under Stress: Proceedings of the International Symposium, sponsored by the International Union of Forest Research Organization (IUFRO, Division I) and hosted by t

During the 1970s and 1980s, Sitka spruce (Picea sitchensis, Bong. Carr. ) was planted extensively on northern Vancouver Island (B. C. , Canada) to regenerate slashburned clearcuts previously occupied by old-growth Thuja p1icata, Donn, Tsuga heterophy11a, Raf. Sarg. , and an ericaceous unders tory shrub salal (Gaul ther ia sha11on, Pursh [CH sites 1 ) . The planted Sitka spruce grew well initially on these sites, but experienced nutritional stress and reduced growth 8 to 14 yr after planting (Germain, 1985; Weetman et a1. , 1990a,b). Accompanying the onset of the nutritional stress was the reestablishment of a complete ground cover of salal, and it has been suggested that there is a causal connection between these two temporally synchronous events (Weetman et al. , 1990a,b). Other ericaceous species have been implicated in nutritional stress in conifer plantations (Mallik, 1987; Robinson, 1972; Handley, 1963; Rose et a1. , 1983). Three hypotheses to explain this nutritional stress were tested in the study reported in this paper: (1) that salal competition for N can provide an adequate explanation for the observed nutritional stress; (2) that salal inhibits the availability of nutrients to seedlings by interfering with their mycorrhizae; and (3) that the fertility of these CH sites declines after 8 yr following clearcutting and slashburning due to the termination of the flush of nutrients (or "assart effect") associated with this disturbance. A series of pot and field experiments was carried out to test these hypotheses. 1 2.

Table of Contents:
I Environmental Pollution and Forest Nutrition.- Environmental Pollution and Impacts on Soils and Forests Nutrition in North America.- Dynamics of “Acute Yellowing” in Spruce Connected with Mg Deficiency.- Effects of Ammonia, Ammonium Sulphate and Sulphur Dioxide on the Frost Sensitivity of Scots Pine (Pinus sylvestris L.).- Survival Rate of Tree and Shrub Seedlings under Extreme Environmental Nitrogen Pollution.- Nutrient Disturbances in Forest Trees and the Nature of the Forest Decline in Quebec and Germany.- Foliar Symptoms on Norway Spruce and Relationships to Magnesium Deficiencies.- Nutritional Disturbances and Declining Armand Pine in Southwestern China.- Element Composition of Leaves and Wood of Beech (Fagus sylvatica L.) on SO2-Polluted Sites of the NE-Bavarian Mountain.- Element Contents of Spruce Needles (P. abies [L] Karst.) Along an Altitudinal Gradient in the Bavarian Alps.- Nutrient Response to Diagnostic Fertilization of Norway Spruce Picea abies (L.) Karst Plantations in Western Quebec, Canada.- Watershed-Scale Responses to Ozone Events in a Pinus strobus L. Plantation.- The Influence of Acid Precipitation and Ozone on Nitrogen Nutrition of Young Loblolly Pine.- Fall Exposure of Beech Saplings (Fagus sylvatica L.) to Ozone and Simulated Acidic Mist: Effects on Gas Exchange and Leachability.- Solute Concentrations and Fluxes of Major Nutrients in Potted Red Spruce Saplings Exposed to Simulated Acid Rain Treatments.- Scattered CaSO4-Crystallites on Needle Surfaces After Simulated Acid Rain as an Indicator of Nutrient Leaching.- Mineral Nutrition, Carbohydrate Content and Cold Tolerance of Foliage of Potted Red Spruce Exposed to Ozone and Simulated Acidic Precipitation Treatments.- The Spatial Heterogeneity of Chemical Properties in Acid Forest Soilsand its Importance for Tree Nutrition.- II Natural Stresses and Forest Nutrition.- Forest Decline and Soil Nutritional Problems in Pacific Areas.- Management of Forests under Nutrient and Water Stress.- Changes in Soil Properties and Site Productivity Caused by Red Alder.- Growth Variation and Environmental Stresses: Long-Term Observations on Permanent Research Plots in Southwestern Germany.- Nutritional Stress in Picea sitchensis Plantations in Coastal British Columbia: The Effects of Gaultheria shallon and Declining Site Fertility.- Mineral Supply of Healthy and Declining Trees of a Young Spruce Stand.- Nutrient Stress in Young Scots Pines Suffering from Needle Loss in a Dry Heath Forest.- The Influence of Weather Variation on Regional Growth of Douglas Fir Stands in the U.S. Pacific Northwest.- The Effect of Nitrogen and Potassium Availability on Scleroderris Canker of Scots Pine Seedlings.- Stress Related Changes in the Architecture of Seedlings of Three Provenances of Eucalyptus camaldulensis Dehnh.- Simulation of Nutrition of Forests under Stress Using Forcyte-11.- III Effects of Liming and Fertilization in the Forest Ecosystem.- Effects of Forest Liming on the Nutrient Status of Podzolic Soils in Finland.- Effects of Liming on Carbon and Nitrogen Mineralization in Coniferous Forests.- The Effects of Forest Liming and Fertilization on Fine-Root Growth.- Effects of Liming and Fertilization on Soil Solution Chemistry in North German Forest Ecosystems.- Liming and Fertilization of Acid Forest Soil: Short-Term Effects on Runoff from Small Catchments.- Liming and Wet Acid Deposition Effects on Tree Growth and Nutrition: Experimental Results.- Bioelement Content and Biomass in Scots Pine: Effect of Acidification and Liming.- Initial Compensation of Acidic Deposition inForest Ecosystems by Different Rock Meals.- Effects of Calcined Magnesite, Magnesium Hydroxide and “Geosan” on Soil Properties in Declining Spruce Stands (NE Bavaria).- Effects of Fertilization with MgSO4 and (NH4)2SO4 on Soil Solution Chemistry, Mycorrhiza and Nutrient Content of Fine Roots in a Norway Spruce Stand.- The Influence of Mg Fertilization on Growth and Mineral Contents of Fine Roots in (Picea abies [Karst.] L.) Stands at Different Stages of Decline in NE-Bavaria.- Foliar Potassium Status Explains Douglas Fir Response to Nitrogen Fertilization in the Inland Northwest, USA.- IV Strategies for Increasing Health and Productivity of Forests.- A New Fertilization Strategy in Declining Forests.- Terrestrial Liming as a Tool to Mitigate Acidification of Woods Lake, NY.- Liming Effects on Some Chemical and Biological Parameters of Soil (Spodosols and Histosols) in a Hardwood Forest Watershed.- An Integrated Watershed/Plot-Scale Study of Element Cycling in Spruce Ecosystems of the Black Forest.- Effects of Magnesium Fertilizer on the Vitality and Nutrition of a European Beech (Fagus sylvatica L.) Stand in the Southern Black Forest of West Germany.- The Use of Organic and Mineral Fertilizers in Reforestation and in Revitalization of Declining Protective Forests in the Alps.- Fertilization of Declining Conifer Stands in the Vosges and in the French Ardennes.- Correction of Magnesium Deficiency in a Young Stand of Norway Spruce.- Second Rotation Decline in P. radiata Plantations in South Australia has been Corrected.- Productivity, Nutrient Immobilization and Soil Chemical Properties in an Eucalyptus globulus plantation under Different Irrigation and Fertilization Regimes.- Effect of Water and Nutrient Supply on Root Distribution in an Eucalyptus globulusPlantation.- Fertilizer Application in Aid of Plantation Establishment in the Savanna Areas of Nigeria.- Relationships between Growth, Mineral Nutrition, and Soils in Young Teak Plantations in Benin and Liberia.- Inherent Differences in Response of Douglas Fir Families to Nitrogen and Phosphorus Supply Levels.- Author Index.