Changes in landscape patterns and associated forest succession on the western slope of the Rocky Mountains, Colorado
Using repeat photography, we conducted a qualitative and quantitative analysis of changes in forest cover on the western slope of the Rocky Mountains in Colorado. For the quantitative analysis, both images in a pair were classified using remote sensing and geographic information system (GIS) technologies. Comparisons were made using three landscape metrics: total relative cover, mean relative patch size, and number of patches per major vegetation type. We noted several important changes in the pattern of the landscape and the structure of the forests. The relative area covered by interspersed, nonforested rangelands has decreased significantly, and the total forest cover across these landscapes has increased. Statistical analyses (ANOVA) of other landscape characteristics (patch number and patch size distribution) did not detect changes. However, nonstatistical observation of the trends in these data revealed that in many cases, there has been important, observable change in the configuration of the landscape at many of these locations. Furthermore, our field data show that 96% of the sampled forests have a conifer component in the overstory, understory, or both.
Proceedings of the First Landscape State-and-Transition Simulation Modeling Conference, June 14–16, 2011, Portland, Oregon
Kerns, Becky K.; Shlisky, Ayn J.; Daniel, Colin J., tech. eds. 2012. Proceedings of the First Landscape State-and-Transition Simulation Modeling Conference, June 14–16, 2011, Portland, Oregon. Gen. Tech. Rep. PNW-GTR-869. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 215 p. The first ever Landscape State-and-Transition Simulation Modeling Conference was held from June 14–16, 2011, in Portland Oregon. The conference brought together over 70 users of state-and-transition simulation modeling tools—the Vegetation Dynamics Development Tool (VDDT), the Tool for Exploratory Landscape Analysis (TELSA) and the Path Landscape Model. The goal of the conference was to (1) provide opportunities for sharing experiences with different applications of the tools, (2) identify major existing conceptual or technological gaps, and develop goals for future state-and-transition simulation model (STSM) development, and (3) start building an international network of STSM users. Eighteen oral presentations and thirteen posters were presented. This proceeding includes thirteen papers that build on some key STSM concepts, applications, and innovations from that conference, and shares them with a wider audience. The goal of these proceedings is to provide a state-of-the-science reference for STSM modelers and users. All papers were peer-reviewed by two blind reviewers and one editor. The presentation of these papers reveals that the STSM approach has been applied to a wide range of management and land-use questions and ecosystems, with an equally wide variation in the amounts of scientific data and expert knowledge available for model parameterization.
The Root System of Aspen
The quaking aspen (Populus tremuloides Michx.) is widely distributed. In the Lake States region it occupies a larger area than any other tree species. Because it occupies such a large area and because of the difficult silvicultural problem which it presents, this species demands careful investigation. The present study was initiated with the objective of adding to the knowledge of the silvics of the species.