Ph.D. - Natural Resources and Environmental Management

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https://hdl.handle.net/10125/20037

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Recognizing Indigenous Knowledge and Values Through the Discipline of Cultural Ecosystem Services: Insights for Research, Management, and Academia
(2024) Nakachi, Alohi; Oleson, Kirsten; Leong, Kirsten; Natural Resources and Environmental Management
Assessing thresholds and outcomes in marine social-ecological systems
(2024) Perng, Lansing Y.; Oleson, Kirsten L. L.; Natural Resources and Environmental Management
Managing carbon in soils, feedstocks, and conversion pathways of tropical agricultural production systems for bioenergy
(2020) Wells, Jon Michael; Crow, Susan E.; Natural Resources and Environmental Management
Causes and Mechanisms of Flooding in Hawaiʻi
(2023) Huang, Yu-Fen; Tsang, Yinphan; Natural Resources and Environmental Management
Regeneration Of ʻiliahi (santalum Paniculatum): Hemiparasitic Relationships In Hawaiian Tropical Dry Forests
(University of Hawaii at Manoa, 2023) Senegal-Thyroff, Emily; Idol, Travis W.; Natural Resources and Environmental Management
Santalum (sandalwood) species, including the endemic Hawaiian species known as ʻiliahi, are ecologically distinct as root hemiparasitic, evergreen trees requiring suitable hosts for long-term resource acquisition. Restoration and sustainable forestry of ‘iliahi at degraded sites, including threatened tropical dry forests, therefore, require supporting host plant populations. In this Ph.D. dissertation, I aimed to improve the survival and establishment of planted ‘iliahi, Santalum paniculatum, seedlings by better understanding the hemiparasitic relationship between ‘iliahi and native tropical dry forest host species. Three projects were implemented to address this overarching goal with the intention of integrating results into current stewardship strategies. The first project compared host dynamics for ʻiliahi paired with different species at varying planting distances. In June 2019, 360 one-year-old container ‘iliahi seedlings were planted in a completely randomized experimental design. ‘Iliahi seedlings were randomly assigned one of nine treatments: ‘iliahi with (1) no host (control), (2) koa at <0.2 m, (3) koa at 0.5 m, (4) koa at 1.0 m, (5) koa at 2.0 m, (6) ‘a‘ali‘i at <0.2 m, (7) ‘a‘ali‘i at 0.5 m, (8) ‘a‘ali‘i at 1.0 m, and (9) ‘a‘ali‘i at 2.0 m. After three years, ‘iliahi grew more and had greater foliar nitrogen concentration when paired with koa (Acacia koa) at a close distance than with ʻaʻaliʻi (Dodonaea viscosa) at any distance or the control with no host. In the second project, I assessed potential tradeoffs between competition and parasitism of ʻiliahi planted under an established koa host canopy. In August 2020, 324 nine-month-old container ‘iliahi seedlings were planted under the canopy of ten-year-old koa trees. Canopy openness above each ‘iliahi seedling varied throughout the planting site with a range of 8.8 % to 90.1 %. ‘Iliahi seedling height and diameter were greater with larger canopy openness, and physiological measurements also increased with greater canopy openness. In the third project, I examined the transfer of resources between ʻiliahi and its host. In April 2021, 2-pot and 3-pot experimental units were established with the roots of ‘iliahi and koa split between containers. The 2-pot and 3-pot units allowed the segregation of roots to examine root exudate transfer and haustoria transfer between ‘iliahi and koa. In April 2022, 15N and 13C stable isotope tracers were applied to specific units and species. We detected 15N root exudate transfer and 15N transfer from the host koa to the hemiparasite ‘iliahi. One- and two-way transfer of 13C were detected in the roots; however, we are cautious as to the biological significance of this result. These results contribute to our understanding of hemiparasitic plants and improve efforts to restore native Hawaiian dry forests, form a sustainable ‘iliahi silviculture basis, and contribute to sustaining functionally compatible and abundant forests.
Conflict Resolution Mechanisms For Developing Marine Protected Area Governance: The Case Of Ko Libong, Thailand
(University of Hawaii at Manoa, 2022) Supholdhavanij, Jutha; Oleson, Kirsten L.; Natural Resources and Environmental Management
This doctoral research aims to provide insight into what governance arrangements could enhance the performance of Thailand’s multiple-use marine protected areas (MPAs) by analyzing the critical features of conflict resolution mechanisms. Conflict resolution mechanisms, comprised of resource governance, applicable procedures, and institutional arrangements, are essential features of MPA governance, whose resilience is critical to marine conservation performance. Yet the role of conflict resolution mechanisms in developing governance that contributes to the performance of marine reserves is underspecified. Furthermore, more efforts are needed to explore social-fit aspects of conflict resolution mechanisms at the local level to explain the strength of the links toward MPA governance protocols. Based on the single-site case study in Thailand, this research focuses on governance aspects of conflict resolution surrounding dugong conservation management in the multiple-use MPA named the Mu Ko Libong Non-Hunting Area. The dissertation has three main research chapters, focusing on (1) the acceptance of rules, (2) the effectiveness of rulemakings, and (3) the range of third-party roles. The dissertation is structured around three main aspects of the linkages between governance and conflict resolution mechanisms, as described by social fit theory: (1) the appropriateness of resource governance to the local context (Chapter 3), (2) the alignment of applicable procedures for conflict resolution to meet the local need (Chapter 4), and (3) the adequacy of institutional arrangements for conflict resolution at the local level (Chapter 5). In the first chapter, I use the theory of self-determination to analyze people’s senses of acceptance. In the second chapter, I use environmental mediation effectiveness theory to evaluate the extent to which each indicator in a rulemaking effectiveness model exposes the achievement of proposed MPA rules and measures. The third chapter uses environmental conflict resolution theory to investigate the range of third-party roles. The research gathers data through various social science methods, including document reviews and analyses, semi-structured interviews, focus group discussions, and direct non-participant observations. Each research chapter purposefully selects key informants. The first chapter focuses on twenty MPA residents represented as local administrative organization staff, dugong conservation group members, and coastal resource users. The second chapter concentrates on ten participants of the rulemaking meetings the related government officials carried out to aid facilitation. The final chapter centers on two local support agent groups, including provincial government officials and local non-governmental organization (NGO) workers, as the potential advisory committee serving dugong conservation management in the Ko Libong area. All three research chapters use content analysis of detailed data to uncover the underlying issues of state-local interactions and explain specific context occurs. The first chapter reveals that the MPA rules facilitate community livelihood activities, as reflected by the perception that MPA rules are supportive and provide the opportunity to mitigate conflicts. In the second chapter, the effectiveness evaluation of rulemaking proceedings points out that meaningful responsiveness to livelihood needs with a concern of improving access to resources can decrease potential conflicts from conservation management. The third chapter determines that the institutional arrangement, through the aspect of the advisory committee possessing convening, facilitation, and mediation functions, is adequate to deal with a situation that needs an intervention. Integrating the three research chapters leads to the conclusion that three social-fit aspects of conflict resolution mechanisms at the local level have considerably contributed to developing the governance of the MPA. Particularly, locally accepted rules, effective rulemakings, and present third-party roles were crucial to pushing good governance in addressing conflicts associated with implementing conservation management, which was necessary to enhance the MPA performance. The critical chance that derives from the exploration in detail through the case is the recognition of relations with relatives as a traditional mechanism for gathering MPA residents to give their voices and taking responsibility for conservation according to MPA management. Relations with relatives enable a mechanism of ownership to build a local movement and acknowledge the community as a primary stakeholder in the planning and decision-making of MPA management initiatives. Ultimately, this dissertation grants insight for using a social-fit perspective to examine the governance of MPAs through understanding conflict resolution mechanisms’ contribution to collaborative conservation management. Collaborative interactions between officials and local people through informal and formal forms of legal proceedings can support the critical aspects of resilience governance. Analysis of the implications of the conflict resolution mechanism for MPA governance leads to understanding the bottom-line aspects of the employment of conflict resolution mechanisms in MPA governance. At the same time, the investigation of institutional arrangements for conflict resolution indicates the necessity to outgrow governance paradigms through adaptive approaches that maintain the balance of social and ecological objectives.
Temporal Ecology of Hawaiian Waterbirds
(University of Hawaii at Manoa, 2022) Harmon, Kristen C.; Price, Melissa R.; Natural Resources and Environmental Management
Conventional conservation has largely been informed by spatial ecology research, such as identifying optimal locations for conserving species and their habitats. However, in a rapidly changing world, it is becoming increasingly important to include temporal ecology, how ecological systems change over time, in conservation planning. In Hawai‘i, state and federal entities have created over 6,000 ha of protected wetland habitat for endangered, endemic Hawaiian waterbirds. Sea level rise poses a threat to many of these protected areas, as many of these wetlands are located on lowlands and nearshore. As Hawaiian waterbirds are currently habitat limited, creating new waterbird habitat will be necessary for the persitance of these populations. However, the uncertainty posed by climate change creates challenges for identifying optimal locations for new waterbird habitat that will be resilient to change. Restoration of Hawaiian wetland agroecosystems (loʻi) under an Indigenous Resource Management (IRM) paradigm may offer a sustainable land-scape level solution to expanding Hawaiian waterbird habitat, as the adaptive, social-ecological framework of these systems increases resilience following disturbance. However, incorporating IRM into conventional conservation approaches has been challenging, in part due to biased perspectives of human-wildlife relationships that are based on shortsighted historical ecology research. Moreover, current conservation goals for recovering Hawaiian waterbird populations are largely informed by research on present-day waterbird ecology. Thus, in this dissertation, I aimed to examine the temporal ecology, including past and present-day ecology, of Hawaiian waterbirds to better understand the future trajectory of their populations. My objectives were to: (1) review empirical evidence for the historical ecology of Hawaiian waterbirds; (2) determine impacts of seasonality and nest-site characteristics on nest survival of the Aeʻo (Hawaiian Stilt – Himantopus mexicanus knudseni); (3) quantify projected losses of Hawaiian waterbird nesting habitat due to sea level rise and the potential for Hawaiian wetland agroecosystems to compensate for these losses. In my first study, I found that the empirical evidence supports the notion that climate change and species introductions were major drivers of post-settlement Hawaiian waterbird extinctions during the Holocene, rather than overhunting and deforestation by Hawaiians. In my second study, nest survival of Aeʻo was found to decrease over the course of the nesting season, possibly due to changes in predation pressure. My results indicate that predation of nests by invasive species, particularly mammals that were introduced to Hawai‘i in the 19th century, is one of the largest threats to Aeʻo populations and likely other extant endangered waterbird populations. The preferred nest-site characteristics of Aeʻo do not improve nest survival, and thus continuous management of predators is critical for Aeʻo reproductive success. In my third chapter I found that sea level rise is projected to reduce currently existing potential waterbird nesting habitat across the main Hawaiian Islands by 29%; however, I found that restoration of loʻi systems may more than compensate for these losses. Together, findings from this dissertation research suggest that restoration of Indigenous agroecosystems, coupled with control of invasive vegetation and predators, may expand conservation of endangered, endemic Hawaiian waterbirds beyond state and federally managed protected areas. My findings help to inform how conservation approaches are most effective when viewed through the perspective of temporal ecology.
Speaking of Abundance: Taíno Ecolinguistic Ontologies, Pre-colonial Biocultural Systems, and Decolonial Pathways to Food and Material Sovereignty in Puerto Rico
(University of Hawaii at Manoa, 2022) Fisk, Jonathan James; Vaughan, Mehana; Natural Resources and Environmental Management
Puerto Rico’s food systems are dangerously precarious, with the islands importing about 90% of its food, a consequence of five centuries of colonialism prioritizing foreign profit over local welfare. Particularly in the aftermath of Hurricane Maria, though, there has been a swelling movement towards food sovereignty on the islands, often aligned with overlapping movements towards the resurgence of Taíno identity and culture. Bringing these movements together, this dissertation focuses on Taíno social-environmental systems, using the recorded Taíno language as the primary vantage point in order to understand the dynamics of pre-colonial social-environmental systems on the islands, the cultures that shaped such systems, and how that can guide us to food and material sovereignty on the islands. This dissertation is grounded in a decolonial research methodology, which I develop and provide as a generalized framework such that other researchers can make use of it as well. Delving into Taíno ecolinguistic ontologies – or the worldviews and relations revealed by the nexus between language and the environment – demonstrates a high degree of naming multiplicity in the Taíno lexicon, particularly for plants and animals with which there was greater intimacy in Taíno cultures. Additionally, redundancy was a prominent feature in pre-colonial Taíno bicultural systems, contributing to socioecological resilience, although there were several categories, especially related to spiritual functions, for which certain biota are simply irreplaceable. Although there are numerous critical barriers obstructing food and material sovereignty for Puerto Rico, the lessons gleaned from Taíno culture, particularly Taíno ecolinguistic ontologies and pre-colonial social-environmental systems, indicate several promising opportunities for cultivating sovereignty: research towards decolonization, mass (re)education, land reclamation, land cultivation & restoration, establishing constellations of care, and building a Pan-Caribbean coalition.
Soil Carbon In Hawaiian Rangelands: Evaluation Of Extent, Controls, And Options For Management
(University of Hawaii at Manoa, 2021) Krueger, Nicholas C.; Ryals, Rebecca; Natural Resources and Environmental Management
Rangelands are a land use type found extensively throughout both the globe and the Hawaiian Islands. These lands provide ecosystem services such as soil carbon sequestration, which can aid in slowing climate change, enhance soil physical and chemical qualities, and potentially provide diversified income for farmers. However, questions remain regarding the extent of sequestered carbon in rangeland soils, as well as the mechanisms controlling the variability of these stocks, especially in Hawaii. The majority of rangelands in Hawaii are situated on Andisols, a soil order known for high soil carbon content due to in part to unique mineralogy. Therefore, my dissertation research sought to intensively sample representative Hawaiian rangelands to identify baseline soil carbon stock, determine a minimum sampling density required for accurate estimates of landscape-scale variability, compare methods of spatial analysis, and to identify environmental factors that affect soil carbon stock distribution. Further, selective dissolution of mineral components of rangeland soils were carried out to relate mineralogy to soil carbon concentration. Finally, I investigated different methods of vegetation management in a silvopastoral production system in a replicated field trial to discern the effect of practice on soil carbon and sward characteristics.High levels of soil carbon stock were found throughout actively grazed rangeland, indicating the importance of these soils in contributing to the regulation of Earth’s climate. Carbon stocks and concentrations varied with environmental as well as mineralogical factors, presenting valuable potential co-variables for consideration in future sampling collections. Integration of livestock in koa (Acacia koa) production systems achieved some understory vegetation management goals, but did not significantly change in soil carbon concentration after one year, highlighting the requirement of long-term studies for soil carbon research. After baseline carbon characteristics are determined, repeated, long-term sampling will be required from different rangeland production systems to identify the effect of management on soil carbon resources. These land use types are important in providing food and ecosystem services to the human population, and a more complete understanding and quantification of their baseline soil qualities, as well as the factors driving those characteristics, will aid in future management decisions that seek to maximize both agricultural productivity and ecosystem health.
Development Of Refined Satellite Land Surface Phenology Detection Approaches For Robust Vegetation Monitoring
(University of Hawaii at Manoa, 2020) Kato, Anna; Carlson, Kimberly M.; Natural Resources and Environmental Management
Land surface phenology (LSP) from remote sensing data can serve as an integrative indicator of climate change impacts on terrestrial ecosystems. Accurate evaluations of changes in the number and timing of phenological events derived from LSP, such as the start of the growing season, are needed to support climate change mitigation and adaption. Yet, current LSP detection approaches are not fully capable of characterizing sub-annual phenological events across biomes. This dissertation aims to develop approaches that enhance robust detection of seasonal and sporadic phenological events from satellite vegetation indices (VIs) to support improved monitoring of vegetation signals. To address this goal, I conducted three studies focused on flux tower sites located across diverse biomes in the United States from 2003 to 2015. First, I evaluated the conditions under which the LSP detection algorithm developed for the Moderate Resolution Imaging Spectroradiometer (MODIS) robustly quantifies the inter-annual variability of growing season length derived from MODIS, Visible Infrared Imaging Radiometer Suite (VIIRS), and in-situ tower VI timeseries. Second, I developed a refined, adaptive LSP detection method and evaluated its ability to detect the start of the growing season across biomes. Algorithm performance was assessed by comparing signals derived from MODIS and VIIRS VIs to those from flux tower estimates of gross primary productivity. Finally, I applied this refined algorithm to detect the number and timing of phenological events across dryland sites with high intra- and inter-annual phenological variability. To identify a robust approach for quantifying such events in such dryland sites, I compared several VIs and phenological transition date detection approaches. Together, results suggest that the MODIS algorithm captures the inter-annual variability of major phenological events but often fails to detect sporadic events. The refined algorithm improved the detectability of irregular events commonly observed in dryland sites, especially when applied to the Enhanced Vegetation Index to quantify the number and peak of phenological events, and to water VIs to detect the start and end of events. The improved approaches to detect LSP developed here are expected to result in more accurate assessments of how climate change affects vegetation in regions with high current or projected future phenological variability.

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