A tree and climate assessment tool for modelling ecosystem response to climate change

Understanding how vulnerable forest ecosystems are to climate change is a key requirement if sustainable forest management is to be achieved. Modelling the response of species in their regeneration niche to phenological and biophysical processes that are directly influenced by climate is one method for achieving this understanding. A model was developed to investigate species resilience and vulnerability to climate change within its fundamental-regeneration niche. The utility of the developed model, tree and climate assessment (TACA), was tested within the interior Douglas-fir ecosystem in south-central British Columbia. TACA modelled the current potential tree species composition of the ecosystem with high accuracy and modelled significant responses amongst tree species to climate change. The response of individual species suggests that the studied ecosystem could transition to a new ecosystem over the next 100 years. TACA showed that it can be an effective tool for identifying species resilience and vulnerability to changes in climate within the most sensitive stage of development, the regeneration phase. The TACA model was able to identify the degree of change in phenological and biophysical variables that control tree establishment, growth and persistence. The response to changes in one or more of these variables resulted in changes in the climatic suitability of the ecosystem for species and enabled a measure of vulnerability to be quantified. TACA could be useful to forest managers as a decision support tool for adaptation actions and by researchers interested in modelling stand dynamics under climate change.     

The responses of professional fire-fighters to disaster

This paper reports the results of a survey of the physical and mental reactions of a group ( N = 72) of members of the South Australian Metropolitan Fire Service (MFS) who were engaged in fighting the bushfires close to Adelaide, 16th-19th February 1983. A questionnaire, designed to elicit reports on both physical and mental reactions to exposure to the fire, as well as perceptions of several measures of social strain and social support, was administered to the firefighters when they came off duty. The results reported show the possible influence of role strain factors in predicting mental reactions, and also demonstrate what may be mediating effects of perceived social support. The paper also discusses methodological problems affecting this and other studies of the reactions of emergency service personnel to disaster.     

Consistency of observations of forest tree defoliation in three European countries

The crown densities of 186 trees of five common European tree species (Norway spruce (Picea abies), silver fir (Abies alba), Scots pine (Pinus sylvestris), oak (Quercus robur) and beech (Fagus sylvatica) were assessed simultaneously by observation teams from France, Germany and the United Kingdom. Major differences in the scores existed, with the maximum difference on any one tree being 45%. Differences tended to be consistent, with the French team scoring more lightly than the German team and the German team more lightly than the UK team. The differences throw into question the value of international comparisons of forest condition, particularly the use of comparative tables of the extent of forest decline in individual European countries.     

Formula allocation as a policy tool: politics and measurement

Formula allocation is a major tool for the distribution of public funds in the United States of America. This paper explores several examples of formulae used in U.S. domestic programmes, looking at their construction, meaning and consequences. The authors argue that the design of formulae is both a political and technical task. The paper concludes with a series of recommendations to improve formulae as tools of distributional policy.     

Back to the basics – Estimating the sensitivity of freshwater to acidification using traditional approaches

This study examines the effects of acidifying sulphur emissions on freshwater ecosystems in the traditional territory of Treaty 8 First Nations in British Columbia (BC). Due to the absence of detailed water chemistry data for most lakes in the region, revised empirical methods for estimating freshwater sensitivity to acidification are formulated using linear regression relationships between individual chemical measurements, and critical loads of acidity calculated using the Steady State Water Chemistry (SSWC) model. Lake alkalinity is the most effective chemical indicator of acidification sensitivity in northeast BC. Critical loads of acidity (CL(A)) estimated using alkalinity range from 0.0827 to 9.48 keq ha^?1 yr^?1. Sulphur deposition estimates range from 0.0113 to 0.303 keq ha^?1 yr^?1 and do not exceed the estimated CL(A) at any of the study lakes. The spatial situation of both the lakes and the emission sources is responsible for the lack of exceedances, and expanded/continued monitoring is recommended to account for geological variability and source proliferation. Measurements of lake conductivity and alkalinity provide a means of community monitoring for freshwater acidification sensitivity as part of cumulative effects management strategies.     

Ozone exposure thresholds and foliar injury on forest plants in Switzerland

Canton Ticino in southern Switzerland is exposed to some of the highest concentrations of tropospheric ozone in Europe. During recent field surveys in Canton Ticino, foliar symptoms identical to those caused by ozone have been documented on native tree and shrub species. In Europe, the critical ozone level for forest trees has been defined at an AOT40 of 10 ppm.h O3 (10 ppm.h accumulated exposure of ozone over a threshold of 40 ppb) during daylight hours over a six-month growing season. The objective of this study was to determine the amount of ambient ozone required to induce visible foliar symptoms on various forest plant species in southern Switzerland. Species were grown within eight open-top chambers and four open plots at the Vivaio Lattecaldo Cantonal Forest Nursery in Ticino, Switzerland. Species differed significantly in terms of the ppb.h exposures needed to cause visible symptoms. The most to least symptomatic species grown within open-plots in this study rank as Prunus serotina, Salix viminalis, Vibrnum lantana, Rhamnus cathartica, Betula pendula, Rumex obtusifolius, Sambucus racemosa, Morus nigra, Prunus avium, Fraxinus excelsior, Rhamnus frangula, Alnus viridis, Fagus sylvatica and Acer pseudoplatanus. Similar rankings were obtained in the non-filtered chamber plots. The ranking of species sensitivity closely follows AOT values for the occurrence of initial symptoms and symptom progression across the remainder of the exposure season. Species that first showed evidence of foliar injury also demonstrated the most sensitivity throughout the growing season, with symptoms rapidly advancing over ca. 25-30% of the total plant leaf surfaces by the end of the observation period. Conversely, those species that developed symptoms later in the season had far less total injury to plant foliage by the end of the observation period (1.5 to < 5% total leaf area injured). The current European ambient ozone standard may be insufficient to protect native plant species from visible foliar injury, and many more native species may be sensitive to ozone-induced foliar injury than are currently known.     

Climate change adaptation and regional forest planning in southern Yukon,Canada

Recent interest in sustainable forest management planning in the Yukon has coincided with growing public awareness of climate change, providing an opportunity to explore how forestry plans are incorporating climate change. In this paper, the Strategic Forest Management Plans for the Champagne and Aishihik First Nations Traditional Territory (CATT) and the Teslin Tlingit Traditional Territory (TTTT) are examined for evidence of adaptation to climate change. For each plan, management policies and practices that are also recognized as ways to adapt to climate change are identified to provide information on the incremental costs and benefits of additional adaptation efforts. A typology for classifying sustainable forest management plans according to how they address climate change is proposed and applied to the CATT and TTTT plans. This typology, which may be useful to any future retrospective assessments on how successful these or other sustainable forest management plans have been in addressing and managing the risks posed by climate change, consists of a matrix that categorizes plans into one of four types; (1) proactive-direct, (2) proactive-indirect, (3) reactive-direct, and (4) reactive-indirect. Neither of the plans available for the southern Yukon explicitly identifies climate change vulnerabilities and actions that will be taken to reduce those vulnerabilities and manage risks. However, both plans have incorporated some examples of ‘best management practices’ for sustainable forest management that are also consistent with appropriate climate adaptation responses. Even in a jurisdiction facing rapid ecological changes driven by climate change, where there is a relatively high level of awareness of climate change and its implications, forestry planning processes have yet to grapple directly with the risks that climate change may pose to the ability of forest managers to achieve the stated goals and objectives of sustainable forest management plans.