Combination of qualitative and quantitative approaches. Analysis of ecosystems. Studying the effects of environmental factors on ecosystems. Phenology in productivity studies. Biomass and productivity models of forest canopies. A synthesis of studies by the harvest method: primary production relations in the temperatue deciduos forests of Japan. Metabolism of terrestrial ecosystems by gas exchange techniques: the brookhaven approach. Insect influences on the forest canopy. Estimation of the effects of phytophagous insects on forest production. Secondary production of birds and mammals. Soil flora: Studies of the number and activity of microorganisms in woodland soils. The role of soil invertebrates in turnover of organis matter and nutrients. Micronutrientes: Forest ecology and systems analysis. Biological cycling of minerals in temperate deciduos forests. Carbon cycle and temperate woodlands. The water flux in temperatue forests: precipitation and evapotranspiration. Measurement and sampling of outputs from watersheds. Models of the hydrolic cycle.