Examining Climate Change Effects on Flowering in Moss Campion

Examining the variation in the collection date of herbarium specimens is a common method for studying the phenological effects of climate change on a flowering plant species. We used herbarium data to examine how warming temperatures have affected flowering time in Silene acaulis in the state of Colorado. Silene acaulis, commonly known as moss campion and cushion pink, is an alpine tundra plant. Using ordinal date of collection as a proxy for flowering date and year collected as a proxy for increasing average temperature, a linear regression test found that there was no significant relationship between increasing temperatures and flowering time. Further examination of the herbarium data revealed a pattern of summertime specimen collection for Silene acaulis. As a species that flowers in response to snow melt, the collection pattern indicates that herbarium data is insufficient for assessing the phenological effects of climate change on Silene acaulis. More intensive research on the relationship between snow melt and flowering time is needed to understand the impacts of climate change on Silene acaulis

Land Use and Socioeconomic Influences on a Vulnerable Freshwater Resource in Northern New England, United States

Land use and cover conversions as well as climatic factors drive current and future threats to freshwater systems. Research from the United States and across the globe has focused on already threatened and degraded freshwater systems, whose recovery requires significant investments. Attention must also be directed to monitoring freshwater systems that may appear robust, yet are likely to face enhanced vulnerabilities in the future due to climate and land use and cover changes. Such proactive monitoring can help identify problems early and provide potential solutions. In this study, we consider the case of Sebago Lake and its watershed in southern Maine; a region that has experienced significant population growth and development activity. Land use, socioeconomic change and water quality trends are monitored over a 20-year period using Landsat imagery, census, water quality and precipitation data. Our results indicate that Developed Land within the watershed has increased from 5.4 % of the total land area in 1987 to 8.9 % in 2009 with associated increases in population and housing activity. Sebago Lake’s water quality indicators from 1990 to 2010 show a directional trend concomitant with this change. The increase in Developed Land is likely to place additional pressures on water quality in the future. The analysis also indicates that precipitation trends play an important role in water quality variability for Sebago Lake. Predicted changes to climatic factors including enhanced spring time precipitation or earlier ice-out conditions combined with further land use change may play an influential role in determining water quality. The analysis highlights emerging areas of concern and reiterates the essential role of proactively monitoring vulnerable systems to help mitigate future threats

DU Undergraduate Showcase: Research, Scholarship, and Creative Works

DU Undergraduate Showcase: Research, Scholarship, and Creative Work

Can the past inform us about Sebago Lake’s future?

Scientists often consider past population trends to make predictions about future growth. Can we do the same with landscapes? Is there a way to examine how land has changed in the past twenty years? And can that help us predict how the land will look in twenty more? The answer to these questions is yes. Landscape trends are important because the quality of water in any lake is influenced by the condition of the land around it. Most important is green space - forested or vegetated land not broken by human development. The simple rule: more green space means more clean water

Land use and socioeconomic influences on a vulnerable freshwater resource in northern New England

Land use and cover conversions as well as climatic factors drive current and future threats to freshwater systems. Research from the United States and across the globe has focused on already threatened and degraded freshwater systems, whose recovery requires significant investments. Attention must also be directed to monitoring freshwater systems that may appear robust, yet are likely to face enhanced vulnerabilities in the future due to climate and land use and cover changes. Such proactive monitoring can help identify problems early and provide potential solutions. In this study, we consider the case of Sebago Lake and its watershed in southern Maine; a region that has experienced significant population growth and development activity

Impact of fuel costs on high-latitude subsistence activities

Most rural residents in Arctic communities rely on motorized transportation to hunt, fish, trap, and gather subsistence resources. Although these technologies have created advantages, one significant disadvantage is that peoples' ability to meet their nutritional and cultural needs now depends on consistent opportunities for wage employment and availability of affordable fuel. Recent qualitative research suggested that rising fuel prices have disrupted subsistence lifestyles in the Arctic. Our objectives were to collaborate with subsistence users in rural Alaskan communities to quantify how rising fuel costs have impacted subsistence activities and explore ways local residents may adapt to the trajectory of change. We conducted interviews with 178 subsistence harvesters in 8 communities. During the last 10 years, 81% of the harvesters reduced the distance they traveled for subsistence and 89% reduced the number of subsistence trips they took because of gasoline costs. During the last 10 years, the median distance traveled to perform subsistence decreased by 60%, and the median annual number of trips taken to perform subsistence decreased by 75%. The change in subsistence activity was similar across and within communities. Eighty-five percent of the people interviewed reported that they were making sacrifices with serious consequences, such as putting off paying monthly bills, to buy gasoline for subsistence activities. To adapt to high gasoline prices, most participants said that they are using more efficient modes of transportation (69%), followed by more sharing of gasoline costs with family and friends (37%), and conducting more multipurpose subsistence trips (20%). With subsistence practices being critical to food security and cultural identity in the Arctic, our results suggest that unaffordable fuel has threatened social resilience. Because global markets drive gasoline prices, we suggest that future research focus on the effectiveness of adaptation options that build resilience into subsistence systems

Resilience of Athabascan subsistence systems to interior Alaska’s changing climateThis article is one of a selection of papers from The Dynamics of Change in Alaska’s Boreal Forests: Resilience and Vulnerability in Response to Climate Warming.

Subsistence harvesting and wild food production by Athabascan peoples is part of an integrated social–ecological system of interior Alaska. We describe effects of recent trends and future climate change projections on the boreal ecosystem of interior Alaska and relate changes in ecosystem services to Athabascan subsistence. We focus primarily on moose, a keystone terrestrial subsistence resource of villages in that region. Although recent climate change has affected the boreal forest, moose, and Athabascan moose harvesting, a high dependence by village households on moose persists. An historical account of 20th century socioeconomic changes demonstrates that the vulnerability of Athabascan subsistence systems to climatic change has in some respects increased while at the same time has improved aspects of village resilience. In the face of future climate and socioeconomic changes, communities have limited but potentially effective mitigation and adaptation opportunities. The extent to which residents can realize those opportunities depends on the responsiveness of formal and informal institutions to local needs. For example, increases in Alaska’s urban population coupled with climate-induced habitat shifts may increase hunting conflicts in low-moose years. This problem could be mitigated through adaptive co-management strategies that project future moose densities and redirect urban hunters to areas of lower conflict. </jats:p