Social and Economic Consequences of Forest Decline in Czechoslovakia

The forests of Czechoslovakia are seriously endangered by air pollution. Another factor contributing to forest decline could be the historical development of silviculture. The study discusses the contemporary state of forests in Czechoslovakia and the outlook to 2000. Continued forest decline could seriously endanger the non-timber functions of forests. The importance of the water-controlling function of forests and its economic efficiency are broadly discussed. The largest part of the paper deals with the influence of forest decline on recreation. Even with limited data, one can observe a continually growing demand for recreation in mountain areas with damaged forests. The reasons lie in the historical development and peculiar features of recreation in this socialist society. The difficulties of forecasting peoples' behavior and their recreational demands is recognized. The last part of the paper deals with the influence of forest decline on production in the wood-processing and pulp-and-paper industries and strategies for their future. It will be necessary to change the structure of the forest-products sector and to investigate the newest technologies for the best utilization of all wood grown, which due to forest damage and the ensuing compulsory sanitation fellings will increase first and then after some years decrease. The study shows that forest decline in Czechoslovakia will lead to high economic losses and high consequent costs and investments in future decades, and can also have serious social consequences even if none have yet been manifested

Forest Potentials and Policy Implications: A Summary of a Study of Eastern and Western European Forest by the IIASA

National timber-assessment studies based on dynamic models are well developed in some European countries, but consistent and dynamic timber assessments for all of Europe are rare and those that exist are not based on formal quantitative models. Because of this lack, a first objective of the IIASA Forest Study was the development of a consistent and formal dynamic model for European forests. Such a model is crucial for formulating relevant forest policies throughout Europe, as well as for calculating long-term timber balance for the region. Finding solutions to the air pollution problem is not easy. Those who design a nd implement solutions to the problem must coordinate local actions to achieve regional goals, regional actions to achieve national goals, and national actions to achieve international goals. We hope that the results of the IIASA Forest Study will play a role in this process

Testing the "Policy Exercise" in Studies of Europe's Forest Sector: Methodological Reflections on a Bittersweet Experience

This report presents the Policy-Exercise concept developed by Brewer (1986), among others. The overall objectives of this Policy-Exercise are: to foster communication and mutual understanding; to synthesize policy-relevant information; and to discover alternatives for the future. The different methodological Policy-Exercise concepts tested by the Forest Study and the lessons learned are described in this paper

Impacts of Changes in Climate and Atmospheric Chemistry on Northern Forest Ecosystems and their Boundaries: Research Directions

In response to numerous suggestions with the research community that boreal forests should be targeted for analyses of potential ecosystem response to impending major changes in climate and atmospheric composition, a task-force meeting for research-planning purposes was held at the International Institute for Applied Systems Analysis in August 1987. Participants discussed objectives for an international collaborative research program on this subject, what the current state of knowledge is, what the relevant research questions are, and what research approaches should be developed to address these questions. This report summarizes the workshop discussions, and presents synopses of working-group discussions on the following types of investigations: (a) historical responses of boreal-forest stands to changing climate and atmosphere using correlational data analyses; (b) response of boreal ecosystems to warm and enhanced-CO2 environments using physical field experiments; (c) response of boreal ecosystems to raised or lowered levels of soil moisture using physical field experiments; (d) long-term behavior of boreal-forest stands in the face of changing atmosphere and climate using measurements from permanent plots; (e) development of comprehensive databases on ecological characteristics of boreal forests and silvical characteristics of boreal-forest tree species based on literature reviews and data syntheses; (f) response and sensitivity of boreal-forest stands and landscapes to changing atmospheric and climatic conditions using simulation models; and (g) response of regional boreal forests to changing climate and atmosphere in the context of forest management using simulation models and policy exercises. The research themes outlined above cover a wide range of spatial and temporal scales. As well, they cover a wide range of organization, from the organism through populations and communities to ecosystems (indeed, ecosystems including socio-economic subsystems). It is concluded that the various studies can benefit immensely from careful coordination that helps each study anchor its process mechanisms in lower hierarchical levels, and find its significance at higher levels. The coordination would also prevent wasteful duplication of effort in different countries where boreal forests exist, and would assist groups of researchers to benefit from (a) regular contact for exchange of data and information that would not normally be available through regular channels of dissemination, and (b) collaborative research arrangements for expensive, long-term, broad-scale projects that otherwise would probably not be possible

Formation of the ηc\eta_c in Two-Photon Collisions at LEP

The two-photon width $\Gamma_{\gamma\gamma}$ of the $\eta_c$ meson has been measured with the L3 detector at LEP. The $\eta_c$ is studied in the decay modes $\pi^+\pi^-\pi^+\pi^-$, $\pi^+\pi^-$K$^+$K$^-$, K$_s^0$K$^\pm\pi^\mp$, K$^+$K$^-\pi^{0}$, $\pi^+\pi^-\eta$, $\pi^+\pi^-\eta'$, and $\rho^+\rho^-$ using an integrated luminosity of 140 pb$^{-1}$ at $\sqrt{s} \simeq 91$ GeV and of 52 pb$^{-1}$ at $\sqrt{s} \simeq 183$ GeV. The result is $\Gamma_{\gamma\gamma}(\eta_c) = 6.9 \pm 1.7 (stat.) \pm 0.8 (sys.) \pm 2.0$(BR) keV. The $Q^2$ dependence of the $\eta_c$ cross section is studied for $Q^2 < 9$ GeV$^{2}$. It is found to be better described by a Vector Meson Dominance model form factor with a J-pole than with a $\rho$-pole. In addition, a signal of $29 \pm 11$ events is observed at the $\chi_c0$ mass. Upper limits for the two-photon widths of the $\chi_c0$, $\chi_c2$, and $\eta_c'$ are also given

Search for Charginos with a Small Mass Difference with the Lightest Supersymmetric Particle at \sqrt{s} = 189 GeV

A search for charginos nearly mass-degenerate with the lightest supersymmetric particle is performed using the 176 pb^-1 of data collected at 189 GeV in 1998 with the L3 detector. Mass differences between the chargino and the lightest supersymmetric particle below 4 GeV are considered. The presence of a high transverse momentum photon is required to single out the signal from the photon-photon interaction background. No evidence for charginos is found and upper limits on the cross section for chargino pair production are set. For the first time, in the case of heavy scalar leptons, chargino mass limits are obtained for any \tilde{\chi}^{+-}_1 - \tilde{\chi}^0_1 mass difference

Search for Manifestations of New Physics in Fermion-Pair Production at LEP

The measurements of hadron and lepton-pair production cross sections and leptonic forward-backward asymmetries performed with the L3 detector at centre-of-mass energies between 130 GeV and 189 GeV are used to search for new physics phenomena such as: contact interactions, exchange of virtual leptoquarks, scalar quarks and scalar neutrinos, effects of TeV strings in models of quantum gravity with large extra dimensions and non-zero sizes of the fermions. No evidence for these phenomena is found and new limits on their parameters are set

Measurement of Hadron and Lepton-Pair Production at 130GeV < \sqrt{s} < 189 GeV at LEP

We report on measurements of e+e- annihilation into hadrons and lepton pairs. The data have been collected with the L3 detector at LEP at centre-of-mass energies between 130 and 189 GeV. Using a total integrated luminosity of 243.7 pb^-1, 25864 hadronic and 8573 lepton-pair events are selected for the measurement of cross sections and leptonic forward-backward asymmetries. The results are in good agreement with Standard Model predictions