© Copyright 2018 Karen L. Dyson
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© Copyright 2018 Karen L. Dyson Parcel-scale development and landscaping actions affect vegetation, bird, and fungal communities on office developments Karen L. Dyson A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy University of Washington 2018 Reading Committee: Gordon Bradley, Chair Ken Yocom Jon Bakker Program Authorized to Offer Degree: Interdisciplinary Program in Urban Design and Planning University of Washington Abstract Parcel-scale development and landscaping actions affect vegetation, bird, and fungal communities on office developments Karen L. Dyson Chair of the Supervisory Committee: Professor Emeritus Gordon Bradley Environmental and Forest Sciences Habitat loss and degradation are primary drivers of extinction and reduced ecosystem function in urban social-ecological systems. While creating local reserves and restoring degraded habitat are important, they are incomplete responses. The matrix, including the built environment, in which these preserves are located must also provide resources for local species. Urban ecosystems can be used to achieve conservation goals by altering human actions to support local species’ habitat needs. I ask what outcomes of development, landscaping, and maintenance actions taken at the parcel scale explained variation in vegetation, bird, and fungal community composition on office developments in Redmond and Bellevue, Washington, USA. These include measures of tree preservation, planting choices, and resource inputs. I compared these with neighborhood and site scale socio-economic variables and neighborhood scale land cover variables found significant in previous urban ecology studies (Heezik et al., 2013; Lerman and Warren, 2011; Loss et al., 2009; Munyenyembe et al.,1989). I found that variables describing the outcome of development and landscaping actions were associated with tree community composition and explained variation in shrub, winter passerine, and fungal community composition. Other variables, including those found significant in previous research, were not significant. Additionally, I observed a wide variety of vegetation communities on office developments, suggesting significant habitat variation within one land use type. My results provide insight into two pieces of social-ecological urban ecosystems. First, the outcomes of human development and landscaping action are related to differences in vegetation communities, and second, that these differences in vegetation community composition—and particularly tree community structure—are related to differences in winter passerine and fungal community composition. My results suggest that there is the potential to alter human actions in the built environment matrix to support local species, including native bird and fungal taxa in the Puget Trough. Important next steps include cultivating landscapes with native trees and revising land use code. The variation in vegetation I observed also suggests that future urban ecology research design must account for within and between land use variability. Contents 1 Introduction 1 1.1 Social-ecological systems .................................. 2 1.2 Ecosystem processes in social-ecological systems ..................... 3 1.3 Reconciliation ecology ................................... 5 1.4 Research questions ..................................... 7 2 Woody vegetation communities on office developments are heterogenous 13 2.1 Introduction ......................................... 13 2.2 Materials and Methods ................................... 20 2.2.1 Study area ..................................... 20 2.2.2 Site selection .................................... 20 2.2.3 Vegetation data collection ............................. 22 2.2.4 Ground cover data collection ........................... 24 2.2.5 Independent variable calculation ......................... 24 2.2.6 Data transformations ............................... 26 2.2.7 Data Analysis .................................... 26 2.3 Results and Discussion ................................... 30 2.3.1 Identifying vegetation community typologies ................... 30 2.3.2 Explaining variation in tree and shrub community structure .......... 33 2.3.3 Variation in office development vegetation communities and implications for sampling design ................................... 36 2.3.4 Study limitations .................................. 39 2.4 Conclusions and future research directions ........................ 39 3 Bird community on office developments is explained by development and land- scaping actions impacting vegetation communities 43 3.1 Introduction ......................................... 43 3.2 Methods ........................................... 50 3.2.1 Study area ..................................... 50 3.2.2 Bird surveys .................................... 51 3.2.3 Bird guilds ..................................... 52 3.2.4 Independent variables ............................... 52 3.2.5 Data analysis .................................... 57 3.3 Results ............................................ 60 3.3.1 Vegetation association preference ......................... 60 3.3.2 Explaining variation in effective species richness ................ 60 3.3.3 Explaining variation in bird community structure ................ 65 3.4 Discussion .......................................... 67 3.4.1 Vegetation association in urban office developments follows other habitats .. 67 3.4.2 Variation in bird effective species richness and community composition .... 68 3.4.3 Study strengths and limitations .......................... 72 3.4.4 Policy and management recommendations .................... 73 3.5 Conclusion ......................................... 76 4 Development and landscaping actions impacting vegetation explain variation in fungal community composition on office developments 79 4.1 Introduction ......................................... 79 4.2 Materials and Methods ................................... 85 4.2.1 Study area ..................................... 85 4.2.2 Fungal datasets ................................... 86 4.2.3 Independent Variables ............................... 91 4.2.4 Data Analysis .................................... 96 4.3 Results ............................................ 98 4.3.1 Fungal observations ................................ 98 4.3.2 Taxonomic comparison between datasets ..................... 99 4.3.3 Independent variables ............................... 99 4.3.4 Explaining variation in effective species richness ................ 99 4.3.5 Explaining variation in fungal community composition ............. 100 4.3.6 Community response to environmental gradients ................ 102 4.4 Discussion .......................................... 107 4.4.1 Explaining variation in effective species richness ................ 107 4.4.2 Explaining variation in community composition ................. 108 4.4.3 Response of fungal taxa to environmental gradients ............... 112 4.4.4 Overall patterns of fungal communities on office developments ........ 113 4.4.5 Research limitations and strengths ........................ 114 4.4.6 Policy implications and guidance for land managers .............. 115 4.4.7 Contributions and future research needs ..................... 117 4.5 Conclusions ......................................... 119 5 Urban ecology helps support urban policy and action 121 6 Research summary and conclusions 127 6.1 Research contributions ................................... 127 6.2 Research limitations and generalizability ......................... 132 6.3 Future research directions ................................. 133 References 137 A Vegetation 163 A.1 Master set of interview questions ............................. 163 A.2 Full tree species list .................................... 165 A.3 Full shrub species list ................................... 168 A.4 Observed sample and population distributions ...................... 172 A.5 Shrub and tree diversity indicies ............................. 174 A.6 Comparing assigned vegetation classes .......................... 177 A.7 Vegetation rank abundance ................................ 179 A.8 PERMANOVA simple multivariate regression results .................. 181 B Bird 183 B.1 All bird species observed .................................. 183 B.2 Explaining variation in effective species richness ..................... 185 B.3 Explaining variation in bird and foraging bird community composition ........ 187 B.4 NMDS visualizations .................................... 191 B.4.1 All birds ....................................... 191 B.4.2 Foraging birds ................................... 192 C Fungi 195 C.1 Supplemental methods detail ............................... 195 C.1.1 Next-generation sequencing ............................ 195 C.1.2 Sequence variant fungal guild assignment .................... 197 C.1.3 Community data handling and transformations ................. 198 C.2 Summary of soil chemistry ................................. 201 C.3 Univariate comparison tables ............................... 203 C.4 Multivariate comparison tables .............................. 204 C.5 TITAN results ....................................... 207 C.5.1 Fungal ecological preference: significant continuous development and land- scape variables ................................... 207 C.5.2 Fungal ecological preference: Soil chemistry gradients ............. 223 C.6 Tree and shrub community preference