JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. Summary1. This survey examined the health of beech (Fagus sylvatica) trees at 72 survey sites in southern Britain. Tree health was assessed using crown thinness, crown architecture and leaf chlorosis as criteria. Diverse variables including soil and stand characteristics were recorded. Relationships were sought between tree health and local site conditions, regional climate and pollution levels.2. Approximately 25% of all beech trees surveyed were in poor health as assessed by crown thinness and architecture. The incidence of chlorosis was generally low at 5%. The different assessment techniques showed markedly different geographical distributions, suggesting that they are not measuring responses to the same environmental variables. Sites of high nature conservation interest for beech showed substantially poorer tree health than other sites. 3. Differences in local environmental conditions could explain much of the variation in levels of beech health. Disturbance, tree age, the openness of the stand and soil characteristics, especially pH and drainage properties, were closely linked to tree health as assessed by crown thinness and architecture. The incidence of chlorosis was most closely associated with the amount of free calcium in the top soil. 4. Crown thinness was positively related to S02 concentration, whereas crown architecture was better in areas with a high concentration of NH3. Trees had thinner and more chlorotic crowns where they had experienced the most intense drought in 1976. 5. For all cases where significant relationships were found between pollutant levels and tree health on acidic soils, health was worse on sites receiving high levels of the pollutant concerned. In contrast, on calcareous soils tree health was better with higher levels of pollutants. The relationship between air pollution and tree health on acidic soils is consistent with the soil acidification hypothesis that has been proposed to explain forest decline.

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Understanding your audiences' perceptions is key to the success of any communication campaign. This research note outlines a pilot study using the Situational Model of publics to segment the broader public. Focus groups were used to study publics' understandings and perceptions of climate change to determine if this issue-based publics model is relevant to this field. The work shows the potential of this model of publics, but in the case of climate change it may need a minor refinement.

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