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Mounting evidence suggests that climate change will cause shifts of tree species range and abundance (biomass). Abundance changes under climate change are likely to occur prior to a detectable range shift. Disturbances are expected to directly affect tree species abundance and composition, and could profoundly influence tree species spatial distribution within a geographical region. However, how multiple disturbance regimes will interact with changing climate to alter the spatial distribution of species abundance remains unclear. We simulated such forest demographic processes using a forest landscape succession and disturbance model (LANDIS-II) parameterized with forest inventory data in the northeastern United States. Our study incorporated climate change under a high-emission future and disturbance regimes varying with gradients of intensities and spatial extents. The results suggest that disturbances catalyze changes in tree species abundance and composition under a changing climate, but the effects of disturbances differ by intensity and extent. Moderate disturbances and large extent disturbances have limited effects, while high-intensity disturbances accelerate changes by removing cohorts of mid-and late-successional species, creating opportunities for early-successional species. High-intensity disturbances result in the northern movement of early-successional species and the southern movement of late-successional species abundances. Our study is among the first to systematically investigate how disturbance extent and intensity interact to determine the spatial distribution of changes in species abundance and forest composition. [ABSTRACT FROM AUTHOR]

The policy debate on whether to strengthen or to remove the legal barriers between banking and commerce has paid little attention to what the practical effects of removing the barriers would be. To help answer this question, this article, the first part of a two-part study, provides an overview of the potential gains of integrating banking and commerce. Economic theory, the authors note, suggests that joint corporate ownership of banks and commercial firms has several potential benefits, including economies of scale and scope, increased internal capital markets, and diversification. Commercial firms could also enjoy a significant reduction in funding costs if affiliation with a bank extended the federal safety net for banks to cover the commercial firms' liabilities. But some benefits are already available without common ownership. Moreover, common ownership may also result in some disadvantages, such as significant diseconomies of scale and scope. Actual experience provides better insight than theory can about the relative magnitudes of the benefits and costs of cross-industry combinations. U.S. experience with limited openings between banking and nonbank activities suggests that the most common combinations were banks with nonbank financial firms, relationships that were authorized by a 1999 reform act. Foreign experience and U.S. conglomerates of nonbank firms in different industries fail to provide compelling evidence for large-scale combinations of banking and commercial firms. [ABSTRACT FROM AUTHOR]