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An examination of climate and land-use change as drivers of population dynamics in breeding birds
Get PDFAnthropogenic land-cover change and climate change are the major drivers of the steep loss of avian biodiversity in past decades. Loss of avian biodiversity is predicted to result in the reduction of ecosystem services and ecological functions. Identifying avian population changes and the drivers of these trajectories is essential for effective species conservation. I documented changes and potential drivers of change for birds in South Korea and the Pacific Northwest of the United States. Because a key determinant of the population ecology for migratory birds is survival during migration and over-wintering, I also quantified migratory paths and wintering grounds for a climate-sensitive bird species.
In Chapter 2, I modeled occupancy dynamics of 52 species of common breeding landbirds in South Korea to provide the first quantitative population status assessment in the region and identify the broad-scale drivers of occupancy dynamics while accounting for imperfect detection survey effort. Twenty species (38%) were declining in average occupancy, and seven of them were declining more than 40% between 1997-2005 and 2014-2019. Notable examples are Black-capped Kingfisher (Halcyon pileata; 95% decline from average occupancy of 0.69 in the first period), Yellow-rumped Flycatcher (Ficedula xanthopygia; 66% decline from average occupancy of 0.19in the first period), and Brown Shrike (Lanius cristatus; 59% decline from average occupancy of 0.17 in the first period). Species that migrate farther and species with higher initial occupancy declined more severely than short-distance migrants, residents, and less common species in general. A comparison with IUCN red list categories for these species revealed that only one species (Brown Shrike) showed quantitative evidence for population declines, and no species were recognized as threatened by the IUCN. Only one species (Chinese Sparrowhawk, Accipiter soloensis) is recognized as Vulnerable by the Korean Government. Using the
IUCN criteria, six species could be re-categorized as Endangered at least in the national level, and one species, the Black-capped Kingfisher could be categorized as Critically Endangered, at least for South Korea. Many of these species are near-endemic to the Korean Peninsula or to East Asia; thus their status in South Korea may represent a large proportion of their global population.
In the Chapter 3, I investigated how old-growth forest vegetation can reduce negative effects of climate warming for breeding bird species using seven-year (2011-2018), fine-scale avian point count data and associated microclimate and vegetation data from the H.J. Andrews Experimental Forest, western Cascades, Oregon. Old-growth forests can buffer under-canopy temperatures and provide higher compositional and structural diversity than simple-structured second-growth forests. I tested two non-mutually exclusive hypotheses based on previous broad-scale studies from the region. First, the microclimate buffering hypothesis suggests that old-growth forests can provide microrefugia for breeding bird populations under the warming climate. And second, the insurance hypothesis explains that higher forest composition and structural diversity in old-growth forests can provide greater resource availability than forests with a simple structure. Eight of twenty species had more positive population trends at sites with cooler microclimates. The cooler microclimates provided by old-growth forest structure, in addition to topographic effects, dampened the negative effect of regional warming on population trends. In contrast, we found weak evidence of the insurance effect of forest composition and structure. For some species, vegetation characteristics changed the slope of the microclimate effect on bird population trends, but with low levels of statistical confidence. For example, the negative effect of microclimate on population trends of Wilson’s Warbler (Cardellina pusilla) and Red Crossbills (Loxia curvirostra) were positively mediated in areas with more diversity in vegetation composition. These results, in summary, suggest that the conservation of old-growth forests and promotion of old-growth characteristics in second-growth forests can potentially reduce the negative effect of warming on declining bird populations in the western coniferous forests.
One of the declining species identified in chapter 3, Hermit Warbler (Setophaga occidentalis), was negatively associated with warmer temperatures in our study, as well as in previous studies. Hermit Warblers are long-distance migrants that spend most of their annual cycle outside of their breeding grounds. However, there is a paucity of information on the migration ecology and migratory connectivity for this species. I tracked 22 individual male birds from six breeding grounds to their wintering locations and back to their breeding range. Hermit Warblers appear to exhibit diffuse migratory connectivity with an overlapping chain migration pattern. Hermit Warblers have relatively short breeding seasons and migrate to montane regions in California during the post-breeding molt. Diffuse migratory connectivity may imply that breeding population declines are more likely to be attributable to breeding ground
environmental change (e.g., forest degradation and climate change) unless there is spatially consistent broad-scale deterioration in habitat conditions across most of the wintering range.
In summary, my study further advances knowledge for avian biodiversity conservation, with particular focus on the demography of breeding bird populations in Oregon, USA, and South Korea, and migration ecology of a declining long-distance migrant songbird species in the Washington, Oregon and California, USA. Such science-based, quantitative species status assessment proved important to correctly identifying sharply declining species. Also, by using information on fine-spatial scale population dynamics and their drivers, I show how old-growth structure and composition can serve to reduce the negative impact of climate warming on some forest bird populations in the Pacific Northwest. Lastly, understanding migratory connectivity and migration ecology can help to identify potential drivers of population change in migratory species
Drivers of Kelp Forest Responses to Global Change: From Populations to Policies
Get PDFKelps are large brown algae in the order Laminariales and are foundation species that form the basis of kelp forests. Present across a quarter of the world’s coastlines, kelp forests provide diverse services to coastal communities, as habitat for commercially and culturally important species, as a food source for humans as well as myriad animals, as raw material used in the pharmaceutical and cosmetics industries, as a place of recreation and tourism, and as a potential source of carbon sequestration. Like all ecosystems on the planet, kelp forests are deeply impacted by human-derived global change. The most comprehensive meta-analysis of global trends in kelp forest cover found that on average kelp forest cover has been declining globally over the past two decades. This negative trend is underlaid by various human impacts. For instance, kelp harvesting is thought to be the primary driver of kelp forest decline in northern Chile, invasive bryozoans in parts of Nova Scotia, and climate-change induced changes in water temperature in western Australia. Furthermore, human impacts can intersect to create cumulative impacts on kelp forests that prevent attribution of kelp forest decline to any one factor. For instance, in Northern California, a marine heat wave, loss of an urchin-eating predator, and unusually high urchin recruitment all contributed to the collapse of Nereocystis forests in 2015.
While some kelp forests in North America are rigorously studied, covered by long-term monitoring, and relatively well-understood (such as Monterey Bay and Point Loma in California), the vast majority are not. In this dissertation, I utilize broad approaches to overcome these data limitations and provide insights into the drivers of kelp forest responses to global change that are relevant to decision-makers. In Chapter 2 I created a 35-year time series of Nereocystis canopy area in Oregon using remote sensing analysis of Landsat satellite data. This dataset showed that multiple-endmember spectral mixing analysis techniques previously utilized to track changes in Macrocystis pyrifera canopy in California can be used with different species and in different regions. Additionally, it retroactively provided rich insights into trends in kelp forest cover across the state and identified novel environmental correlates of kelp forest cover, such as a positive association with winter wave height that have deepened our understanding of the population biology and ecology of Nereocystis. Insights from this work has been shared with the Oregon Department of Fish and Wildlife, the Oregon Kelp Alliance, the Elakha Alliance, the Coquille Tribe, Senator Jeff Merkley and others in order to support policy-making, restoration, and science funding efforts related to kelp in Oregon.
In Chapter 3, I used the contributed data of over 30 collaborators to provide range-wide insights into the impacts of disease on a Pycnopodia helianthoides, a urchin-eating predator whose loss has been tied to kelp forest overgrazing. This work found that disease-driven mortality had been so severe (~99%) in the southern half of the species range that recovery to ecologically-relevant population levels was unlikely to happen in a time frame relevant for kelp forests. In the northern half of the range however, populations were impacted less dramatically and could still be found in relatively high densities, although densities were patchy. Additionally, we found that the importance of temperature in predicting Pycnopodia distributions rose dramatically after the disease event, indicating that temperature-disease interactions were related to the latitudinal pattern in disease severity. Furthermore, through a partnership with The Nature Conservancy, this work has influenced global Pycnopodia conservation efforts through the successful listing of the species as Critically Endangered on the IUCN Red List, the formation of a Pycnopodia Recovery Working group, and incorporation into a Pycnopodia Recovery Roadmap.
Finally, in Chapter 4, I brought together insights from the scholarly literature on kelp forest ecology, the framework of Ecosystem Based Management (EBM), and regional case studies of ongoing management to synthesize cross-regional principles for managing kelp forests sustainably. Our case studies focused on three regions, each with unique socioecological contexts around kelp forests: northern Chile, California (USA), and British Columbia (Canada). Drawing lessons from across disciplines and regions, we identified six principles for kelp forest EBM: 1) monitoring at biologically relevant temporal and spatial scales, 2) assessing and addressing cumulative impacts, 3) managing across spatial scales, 4) co-management with users, 5) employing rapid adaptive management and/or the precautionary principle, and 6) managing food web connections. We explore and illustrate these concepts using examples from multiple regions to provide concrete guidance on EBM-inspired strategies that are likely to improve kelp forest management outcomes. We hope this work can be a starting place for further discussion around and development of best practices in kelp forest management
Classification of Native Vegetation of Oregon - 2019
Get PDFThis classification is an update of the 2004 classification of native vegetation of Oregon by Kagan, Christy, Murray and Titus. As before, this classification lists the native plant associations known to occur in Oregon, and includes both successional and climax vegetation types that were part of the presettlement landscape of Oregon and can still be found in the state. It serves as an index to the diversity, distribution and relative rarity of the state's native plant associations, and as a guide to their literature
Assessing the impact of multicomponent diffusion in direct numerical simulations of premixed, high-Karlovitz, turbulent flames: hydrogen data
No full textThis data contains results from direct numerical simulations of premixed, two-dimensional unsteady and three-dimensional, turbulent hydrogen/air flames, using the multicomponent and mixture-averaged diffusion models. In particular, this dataset contains information about diffusion flux angles and magnitudes. We performed the simulations using the finite-difference code NGA; simulation details are described completely in the associated article
A quantitative wildfire risk assessment using a modular approach of geostatistical clustering and regionally distinct valuations of assets—A case study in Oregon
Get PDFThe intensity and scale of wildfires has increased throughout the Pacific Northwest in recent decades, especially within the last decade, destroying vast amounts of valuable resources and assets. This trend is predicted to remain or even magnify due climate change, growing population, increased housing density. Furthermore, the associated stress of prolonged droughts and change in land cover/land use puts more population at risk. We present results of a multi-phase Extension Fire Program Initiative combining fire model results based on worst-case meteorological conditions recorded at 50 weather stations across Oregon with spatially distinct valuations of resources and assets based on regional ecological and socio-economic conditions. Our study focuses on six different Fire Service Areas covering the state of Oregon. We used a geostatistical approach to find weather stations that provide worst-case meteorological input data on record for representative sub-domains. The results provide regionally distinct assessments of potential value loss by wildfire and show that, depending on the region, 12% to 52% of the highest relative risk areas are on private land. This underscores the need to unite strategies and efforts on the landscape scale by including different landowners, managers, and stakeholders of public land and private land efficiently address wildfire damage protection and mitigation. Our risk assessments closely agreed with risks identified during landscape-scale ground projects
Hyperspectral imagery of Pinus strobiformis infected with fungal pathogen
No full textHyperspectral images were taken from March till October, 2018, of southwestern white pine (Pinus strobiformis), SWWP, seedlings of ten different seed-source families. Half of the seedlings were inoculated with white pine blister rust (Cronartium ribicola). Visual assessments of vigor coincided with hyperspectral data acquisition.
The aim of the experiment was to use hyperspectral data to automaticaly and objectively identify infection and degree of infection in SWWP seedlings. Moreover, we developed and evaluated a feature importance algorithm to identify the most usefull hyperspectral features for classification tasks
Assessing the impact of multicomponent diffusion in direct numerical simulations of premixed, high-Karlovitz, turbulent flames: n-heptane data
No full textThis data contains results from direct numerical simulations of premixed, three-dimensional, turbulent n-heptane/air flames, using the multicomponent and mixture-averaged diffusion models. In particular, this dataset contains information about diffusion flux angles and magnitudes. We performed the simulations using the finite-difference code NGA; simulation details are described completely in the associated article
Grounding Institutional Partnerships in Structures for Broader Impact Design: Summative Evaluation Report
Get PDFThis report presents summative evaluation results for a National Science Foundation funded project entitled Grounding Institutional Partnerships in Structures for Broader Impacts Design (BID). The project represents a collaboration between five institutions: Institute for Learning Innovation, The STEM Research Center at Oregon State University, Scicenter, University of Washington-Bothell, and University of Wisconsin-Madison. BID aimed at creating an inter-institutional structure and toolkit to assist higher education institutions (HEIs) and informal science education organizations (ISEs) in developing sustainable institutional partnerships through collaboration around the design of informal STEM education-based Broader Impacts (BI) experiences. The project built upon the Portal to the Public (PoP) framework, bringing together research support professionals, STEM education professionals and Principal Investigators at HEIs with practitioners at ISEs (i.e., BID partners) to enhance BI experiences for the public by leveraging human resources through intentional coordination and partnerships. This report addresses the impact of this collective work, serves as a record of the project, and as a resource for future partnerships that support BI
Explorer At Large: Pilot Implementation in Ohio : Evaluation Report 2019-2020
Get PDFExplorer At Large (XAL) is an education initiative designed to encourage students and their families to be curious and develop an identity as an explorer. XAL delivers a holistic ecosystem of learning opportunities that model curiosity and exploration skills and consists of the following four primary components: 1) freely distributed videos that invite students to observe exploration; 2) instructional materials (teacher guides, hands-on classroom and outdoor activities) that guide students in practicing exploration; 3) field trips to settings in students’ local communities that empower students to experience exploration; and 4) family moments that encourage
parent/caregiver engagement and inspires students to share exploration.
This report shares evaluation findings from piloting the XAL instructional materials with K and 3rd grade teachers and students from schools in Ohio. The report is following up on an earlier pilot that focused on schools in the Columbus region
Mapping Untreated and Semi-treated Wastewater Effluent off the Coast of Gaza with Sentinel-1 Time Series Data
Get PDFThe Israeli-Palestinian conflict is one of the most contested and complicated conflicts in the world. As one of the occupied Palestinian Territories recognized by the United Nations, the social and environmental conditions in Gaza are impossible to understand without reference to the occupation of Gaza by its neighbor Israel. Hostilities have led to the damage of wastewater infrastructure, including sewage pipe systems and wastewater treatment plants, while Israel’s blockade on Gaza has prevented resources for building and repairing wastewater infrastructure. Because of the damaged or insufficient wastewater infrastructure, tens of thousands of liters of untreated and semi-treated wastewater is discharged into the Mediterranean Sea from Gaza on a daily basis. Despite international recognition of the wastewater pollution, Gazans still live with inadequate access to drinking water and sanitation. Organizations in the region like EcoPeace, who promote environmental peacebuilding, have supported the construction of additional wastewater infrastructure in Gaza, but there is often still a lack of political incentive to fully invest in these improvements. In an effort to document the protracted but sometimes hidden effects of this conflict on the environment and, by extension, the people of Gaza, Sentinel-1 synthetic aperture radar (SAR) time series data were used to map apparent wastewater plumes flowing directly into the Mediterranean Sea from known wastewater outfalls in Gaza from January 2017 to December 2019. A Random Forest classification of 97 Sentinel-1 images was used to identify 698 apparent wastewater plumes at 11 outfalls. Data on plume area and frequency were paired with field-based wastewater data to test for relationships between the spatial and temporal patterns of apparent wastewater plumes and the spatial and temporal patterns of wastewater effluent and biochemical oxygen demand (BOD) from wastewater discharged from outfalls on Gaza. Results show that SAR successfully detected apparent wastewater plumes derived from untreated and semi-treated wastewater, and that plumes were frequently detected at outfalls discharging semi-treated wastewater although plumes also varied in area between different dates and among different outfalls. Correlations between the plume areas and wastewater effluent volume and BOD were generally low and not statistically significant. Various reasons for the weak correlation between SAR and field data were examined, and suggestions for future work to overcome study limitations are presented. The accurate and reliable data from satellite remote sensing data highlighting the environmental detriment of untreated wastewater discharged into Mediterranean Sea offers a new and objective view into the indirect effects of protracted conflict. As such, these data may help to incentivize Israel and other bordering nations to provide additional resources and materials to Gaza for the rapid improvement of wastewater treatment and ultimately better access to water and sanitation in spite of the political conflict