Regional climate, federal land management, and the social-ecological resilience of southeastern Alaska

Thesis (Ph.D.) University of Alaska Fairbanks, 2007Complex systems of humans and nature often experience rapid and unpredictable change that results in undesirable outcomes for both ecosystems and society. In circumpolar regions, where multiple converging drivers of change are reshaping both human and natural communities, there is uncertainty about future dynamics and the capacity to sustain the important interactions of social-ecological systems in the face of rapid change. This research addresses this uncertainty in the region of Southeast Alaska, where lessons learned from other circumpolar regions may not be applicable because of unique social and ecological conditions. Southeast Alaska contains the most productive and diverse ecosystems at high latitudes and a human population almost entirely isolated and embedded in National Forest lands; these qualities underscore the importance of the region's climate and federal management systems, respectively. This research presents a series of case studies of the drivers, dynamics, and outcomes of change in regional climate and federal management, and theoretically grounds these studies to understand the regional resilience to change. Climate change in Southeast Alaska is investigated with respect to impacts on temperate rainforest ecosystems. Findings suggest that warming is linked to emergence of declining cedar forests in the last century. Dynamics of federal management are investigated in several studies, concerning the origins and outcomes of national conservation policy, the boom-bust history of the regional timber economy, and the factors contributing to the current 'deadlock' in Tongass National Forest management. Synthesis of case study findings suggests both emergent phenomena (yellow-cedar decline) and cyclic dynamics (timber boom-bust) resulting from the convergence of ecological and social drivers of change. Adaptive responses to emergent opportunities appear constrained by inertia in management philosophies. Resilience to timber industry collapse has been variable at local scales, but overall the regional economy has experienced transition while retaining many of its key social-ecological interactions (e.g., subsistence and commercial uses of fish and wildlife). An integrated assessment of regional datasets suggests a high integrity of these interactions, but also identifies critical areas of emergent vulnerability. Overall findings are synthesized to provide policy and management recommendations for supporting regional resilience to future change.Introduction : Southeast Alaska as a social-ecological system -- Climate change and forest decline in Southeast Alaska -- Significance of wilderness conservation in Southeast Alaska : outcomes of the Alaska lands debate over the Tongass National Forest -- Dynamics of federal land management during the 20th century -- Factors influencing the reorganization of federal land management -- Conclusions : regional dynamics and social-ecological resilience of Southeast Alaska

Influence of Climate on Long-Term Recovery of Adirondack Mountain Lakewater Chemistry from Atmospheric Deposition of Sulfur and Nitrogen

In this study, we assessed temporal patterns and long-term trends in nitrate (NO3-), two forms of aluminum (inorganic, Ali, and organic, Alo), and dissolved organic carbon (DOC) concentrations in the water of 29 Adirondack Mountain, New York lakes, and the potential effects of ambient weather conditions (i.e., climatic variation) on these patterns and trends

Mapping historical forest biomass for stock-change assessments at parcel to landscape scales

Understanding historical forest dynamics, specifically changes in forest biomass and carbon stocks, has become critical for assessing current forest climate benefits and projecting future benefits under various policy, regulatory, and stewardship scenarios. Carbon accounting frameworks based exclusively on national forest inventories are limited to broad-scale estimates, but model-based approaches that combine these inventories with remotely sensed data can yield contiguous fine-resolution maps of forest biomass and carbon stocks across landscapes over time. Here we describe a fundamental step in building a map-based stock-change framework: mapping historical forest biomass at fine temporal and spatial resolution (annual, 30m) across all of New York State (USA) from 1990 to 2019, using freely available data and open-source tools. Using Landsat imagery, US Forest Service Forest Inventory and Analysis (FIA) data, and off-the-shelf LiDAR collections we developed three modeling approaches for mapping historical forest aboveground biomass (AGB): training on FIA plot-level AGB estimates (direct), training on LiDAR-derived AGB maps (indirect), and an ensemble averaging predictions from the direct and indirect models. Model prediction surfaces (maps) were tested against FIA estimates at multiple scales. All three approaches produced viable outputs, yet tradeoffs were evident in terms of model complexity, map accuracy, saturation, and fine-scale pattern representation. The resulting map products can help identify where, when, and how forest carbon stocks are changing as a result of both anthropogenic and natural drivers alike. These products can thus serve as inputs to a wide range of applications including stock-change assessments, monitoring reporting and verification frameworks, and prioritizing parcels for protection or enrollment in improved management programs.Comment: Manuscript: 24 pages, 7 figures; Supplements: 12 pages, 5 figures; Submitted to Forest Ecology and Managemen

Überlegungen zur Einführung eines revolvierenden Stadtentwicklungsfonds in Leipzig im Rahmen des Projektes CSI Europe

Die Stadt Leipzig hat sich am internationalen Austauschprojekt "CSI Europe - City Sustainable Investment" (2011-2015) beteiligt. Neben der europäischen Kooperation zum Thema hat die Stadt Leipzig ihrerseits einen Expertenrat eingesetzt, um die Eckpunkte eines lokalen Stadtentwicklungsfonds in einer Machbarkeitsstudie zu diskutieren. Der Artikel fasst die Ergebnisse der Machbarkeitsstudie zusammen. Es wird vorgeschlagen, in dem einzurichtenden Fonds städtische Gelder, JESSICA-Mittel und private Gelder in separat bewirtschafteten Teilfonds einzubeziehen. Insbesondere durch den Einbezug privater Gelder entsteht der Zwang, den Fonds bzw. das Fondsmanagement bei einer Bank anzusiedeln. Grundsätzlich gilt, dass der Stadtentwicklungsfonds Projekte, die aufgrund besonderer Risiken keine Bankenfinanzierung erhalten, durch Darlehen oder Bürgschaften finanziert. Die Projekte zeichnen sich durch eine Orientierung an den stadtentwicklungspolitischen Zielen aus. Im Fazit werden Klärungsbedarf und erste mögliche Schritte zur Einführung eines solchen Fonds dargestellt.As part of the "CSI Europe - City Sustainable Investment" network (2011-2015) the City of Leipzig set up an expert panel to undertake a feasibility study and elaborate key aspects of an urban development fund. The following paper outlines the panel's results and recommendations. Most significant, a combined use of public municipal grants, JESSICA-subsidies and private capital in separately managed subfunds is proposed. Particularly due to the inclusion of private capital, this calls for the professional management of the fund within a financial institution. Fundamentally, the fund provides loans or guarantees to projects which have been unable to obtain regular bank financing due to special risk structures, but which nonetheless strongly contribute to urban development policy goals. The paper concludes by outlining open questions and the first steps necessary to introduce such a fund

Historical Patterns and Effects of Changes In Adirondack Climates Since the Early 20th Century

Analysis of weather data from seven United States Historical Climatology Network stations in the Adirondack region reveals statistically significant warming over the last 30 years during June and September, but no significant trends in the other months. The warmest intervals of the 1926-2005 period were the early 1930s, 1949-1954, and 1997-2003. These findings are consistent with similar analyses of northern New York weather data by Kathie Delio, but somewhat less so with earlier works by the first author and others. In this paper, we also discuss the effects of various interpretive methodologies on the study of regional climate and present new phonological data from the Adirondack region. We find little evidence of major biotic responses to weather trends in recent decades, perhaps because most such trends are still largely obscured by inter-annual variability, but a significant reduction in the duration of ice cover has occurred on local lakes. In addition, an increase of river discharge during the 20th century probably reflects a long-term increase in precipitation, particularly during fall

Regional growth decline of sugar maple (Acer saccharum) and its potential causes

Sugar maple (Acer saccharum Marsh) has experienced poor vigor, regeneration failure, and elevated mortality across much of its range, but there has been relatively little attention to its growth rates. Based on a well‐replicated dendrochronological network of range‐centered populations in the Adirondack Mountains (USA), which encompassed a wide gradient of soil fertility, we observed that the majority of sugar maple trees exhibited negative growth trends in the last several decades, regardless of age, diameter, or soil fertility. Such growth patterns were unexpected, given recent warming and increased moisture availability, as well as reduced acidic deposition, which should have favored growth. Mean basal area increment was greater on base‐rich soils, but these stands also experienced sharp reductions in growth. Growth sensitivity of sugar maple to temperature and precipitation was non‐stationary during the last century, with overall weaker relationships than expected. Given the favorable competitive status and age structure of the Adirondack sugar maple populations sampled, evidence of widespread growth reductions raises concern over this ecologically and economically important tree. Further study will be needed to establish whether growth declines of sugar maple are occurring more widely across its range

The Effect of Map Boundary on Estimates of Landscape Resistance to Animal Movement

BACKGROUND: Artificial boundaries on a map occur when the map extent does not cover the entire area of study; edges on the map do not exist on the ground. These artificial boundaries might bias the results of animal dispersal models by creating artificial barriers to movement for model organisms where there are no barriers for real organisms. Here, we characterize the effects of artificial boundaries on calculations of landscape resistance to movement using circuit theory. We then propose and test a solution to artificially inflated resistance values whereby we place a buffer around the artificial boundary as a substitute for the true, but unknown, habitat. METHODOLOGY/PRINCIPAL FINDINGS: We randomly assigned landscape resistance values to map cells in the buffer in proportion to their occurrence in the known map area. We used circuit theory to estimate landscape resistance to organism movement and gene flow, and compared the output across several scenarios: a habitat-quality map with artificial boundaries and no buffer, a map with a buffer composed of randomized habitat quality data, and a map with a buffer composed of the true habitat quality data. We tested the sensitivity of the randomized buffer to the possibility that the composition of the real but unknown buffer is biased toward high or low quality. We found that artificial boundaries result in an overestimate of landscape resistance. CONCLUSIONS/SIGNIFICANCE: Artificial map boundaries overestimate resistance values. We recommend the use of a buffer composed of randomized habitat data as a solution to this problem. We found that resistance estimated using the randomized buffer did not differ from estimates using the real data, even when the composition of the real data was varied. Our results may be relevant to those interested in employing Circuitscape software in landscape connectivity and landscape genetics studies