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Description
Stream flow permanence plays a critical role in determining floristic composition, abundance, and diversity in the Sonoran Desert, but questions remain about the effects of stream flow permanence on butterfly composition, abundance, and diversity. Understanding the effects of flow permanence on butterflies and relevant subsets of butterflies (such as butterflies

Stream flow permanence plays a critical role in determining floristic composition, abundance, and diversity in the Sonoran Desert, but questions remain about the effects of stream flow permanence on butterfly composition, abundance, and diversity. Understanding the effects of flow permanence on butterflies and relevant subsets of butterflies (such as butterflies whose host plants are present) and comparing them to these same effects on plants and relevant subsets of plants (such as butterfly nectar plants and larval host plants) provided insight into pollinator and riparian conservation and restoration.

I surveyed four Sonoran desert stream sites, and found significant relationships between flow permanence and plant and butterfly species richness and abundance, as well as strong relationships between plant and butterfly abundance and between plant and butterfly species richness. Most notably, my results pointed to hosted butterflies as a break-out category of butterflies which may more clearly delineate ecological relationships between butterfly and plant abundance and diversity along Sonoran Desert streams; this can inform conservation decisions. Managing for hosted (resident) butterflies will necessarily entail managing for the presence of surface water, nectar forage, varying levels of canopy cover, and plant, nectar plant, and host plant diversity since the relationships between hosted butterfly species richness and/or abundance and all of these variables were significant, both statistically and ecologically.
ContributorsButler, Lane (Author) / Stromberg, Juliet C. (Thesis advisor) / Makings, Elizabeth (Committee member) / Pearson, David L (Committee member) / Boggess, May (Committee member) / Buchmann, Stephen (Committee member) / Arizona State University (Publisher)
Created2015
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Description
The Upper Verde River of central Arizona flows through a landscape of complex geology at the meeting of seven biotic communities and three physiographic provinces. This has resulted in notably diverse flora and fauna and a hub of rare and endemic plant species. The river has sustained cultures since pre-history,

The Upper Verde River of central Arizona flows through a landscape of complex geology at the meeting of seven biotic communities and three physiographic provinces. This has resulted in notably diverse flora and fauna and a hub of rare and endemic plant species. The river has sustained cultures since pre-history, however current regional water use is predicted to diminish streamflow over the next century. Prior to this project, no floristic inventory had been conducted along any section of the Verde. The purpose of this study was to develop a Flora of the Upper Verde River, with the goals of documenting rare and endemic species, the composition and abundance of wetland plants, and the factors shaping plant diversity in the region.

I made a total of 1856 collections and reviewed past collections to produce a checklist of 729 vascular plant taxa in 403 genera and 98 families. The most species-rich family is the Poaceae, followed by Asteraceae and Fabaceae. The flora includes 159 wetland taxa, 47 endemics, and 26 taxa of conservation concern, eight of which are Federally listed. Several new populations were found in these categories and of rarely-collected taxa including one state record, three county records and several range extensions. I report on the local status of several endemics, wetland taxa with limited distributions, and relict populations of a tepary bean (Phaseolus acutifolius) that were likely transported to the region and cultivated by pre-Columbian cultures. I categorize thirteen distinct plant communities, the most abundant being Pinyon/Juniper Woodland, Chihuahuan/Apacherian Scrub, and Riparian Deciduous Forest.

Four primary factors influence floristic diversity of the Upper Verde region: 1) a location at the junction of three physiographic and floristic provinces—represented by co-occurrence of species with affinities to the Sonoran, Intermountain and Madrean regions, 2) geologic diversity—as distinct groups of species are associated with particular geologic types, 3) topographic and habitat complexity—allowing species adapted to disparate environments to co-occur, and 4) human introductions—since over 15% of the flora is composed of introduced species from Eurasia and several taxa were introduced to the region and cultivated by pre-Columbian cultures.
ContributorsCoburn, Francis S (Author) / Stromberg, Juliet C. (Thesis advisor) / Landrum, Leslie R (Thesis advisor) / Makings, Elizabeth (Committee member) / Fertig, Walter F (Committee member) / Arizona State University (Publisher)
Created2015
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Description
Baseline community composition data provides a snapshot in time that allows changes in composition to be monitored more effectively and can inform best practices. This study examines Arizona Upland plant community composition of the Sonoran Desert through three different lenses: floristic inventory, and fire and reseeding effects.

A floristic inventory was

Baseline community composition data provides a snapshot in time that allows changes in composition to be monitored more effectively and can inform best practices. This study examines Arizona Upland plant community composition of the Sonoran Desert through three different lenses: floristic inventory, and fire and reseeding effects.

A floristic inventory was conducted at Cave Creek Regional Park (CCRP), Maricopa County, AZ. One hundred fifty-four taxa were documented within Park boundaries, including 148 species and six infraspecific taxa in 43 families. Asteraceae, Boraginaceae, and Fabaceae accounted for 40% of documented species and annuals accounted for 56% of documented diversity.

Fire effects were studied at three locations within McDowell Sonoran Preserve (MSP), Scottsdale, AZ. These fires occurred throughout the 1990s and recovered naturally. Fire and reseeding effects were studied at the site of a 2005 fire within CCRP that was reseeded immediately following the fire.

Two questions underlie the study regarding fire and reseeding effects: 1) How did fire and reseeding affect the cover and diversity of the plant communities? 2) Is there a difference in distribution of cover between treatments for individual species or growth habits? To address these questions, I compared burned and adjacent unburned treatments at each site, with an additional reseeded treatment added at CCRP.

MSP sites revealed overall diversity and cover was similar between treatments, but succulent cover was significantly reduced, and subshrub cover was significantly greater in the burn treatment. Seventeen species showed significant difference in distribution of cover between treatments.

The CCRP reseeded site revealed 11 of 28 species used in the seed mix persist 12 years post-fire. The reseeded treatment showed greater overall diversity than burned and unburned treatments. Succulent and shrub cover were significantly reduced by fire while subshrub cover was significantly greater in the reseeded treatment. Sixteen species showed significant difference in distribution of cover between treatments.

Fire appears to impact plant community composition across Arizona Upland sites. Choosing species to include in seed mixes for post-fire reseeding, based on knowledge of pre-fire species composition and individual species’ fire responses, may be a useful tool to promote post-fire plant community recovery.
ContributorsBarron, Kara Lynn (Author) / Pigg, Kathleen B (Thesis advisor) / Stromberg, Juliet (Thesis advisor) / Makings, Elizabeth (Committee member) / McCue, Kimberlie (Committee member) / Arizona State University (Publisher)
Created2018
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Description
Dissolved organic matter (DOM) is an important part of aquatic foodwebs because it contains carbon, nitrogen, and other elements required by heterotrophic organisms. It has many sources that determine its molecular composition, nutrient content, and biological lability and in turn, influence whether it is retained and processed in the stream

Dissolved organic matter (DOM) is an important part of aquatic foodwebs because it contains carbon, nitrogen, and other elements required by heterotrophic organisms. It has many sources that determine its molecular composition, nutrient content, and biological lability and in turn, influence whether it is retained and processed in the stream reach or exported downstream. I examined the composition of DOM from vascular wetland plants, filamentous algae, and riparian tree leaf litter in Sonoran Desert streams and its decomposition by stream microbes. I used a combination of field observations, in-situ experiments, and a manipulative laboratory incubation to test (1) how dominant primary producers influence DOM chemical composition and ecosystem metabolism at the reach scale and (2) how DOM composition and nitrogen (N) content control microbial decomposition and stream uptake of DOM. I found that differences in streamwater DOM composition between two distinct reaches of Sycamore Creek did not affect in-situ stream respiration and gross primary production rates. Stream sediment microbial respiration rates did not differ significantly when incubated in the laboratory with DOM from wetland plants, algae, and leaf litter, thus all sources were similarly labile. However, whole-stream uptake of DOM increased from leaf to algal to wetland plant leachate. Desert streams have the potential to process DOM from leaf, wetland, and algal sources, though algal and wetland DOM, due to their more labile composition, can be more readily retained and mineralized.
ContributorsKemmitt, Kathrine (Author) / Grimm, Nancy (Thesis advisor) / Hartnett, Hilairy (Committee member) / Throop, Heather (Committee member) / Arizona State University (Publisher)
Created2018
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Description
It’s no secret that wetlands have dramatically declined in the arid and semiarid American West, yet the small number of wetlands that persist provide vital ecosystem services. Ciénega is a term that refers to a freshwater arid-land wetland. Today, even in areas where ciénegas are prominent they occupy less than

It’s no secret that wetlands have dramatically declined in the arid and semiarid American West, yet the small number of wetlands that persist provide vital ecosystem services. Ciénega is a term that refers to a freshwater arid-land wetland. Today, even in areas where ciénegas are prominent they occupy less than 0.1% of the landscape. This investigation assesses the distribution of vascular plant species within and among ciénegas and address linkages between environmental factors and wetland plant communities. Specifically, I ask: 1) What is the range of variability among ciénegas, with respect to wetland area, soil organic matter, plant species richness, and species composition? 2) How is plant species richness influenced locally by soil moisture, soil salinity, and canopy cover, and regionally by elevation, flow gradient (percent slope), and temporally by season? And 3) Within ciénegas, how do soil moisture, soil salinity, and canopy cover influence plant species community composition? To answer these questions I measured environmental variables and quantified vegetation at six cienegas within the Santa Cruz Watershed in southern Arizona over one spring and two post-monsoon periods. Ciénegas are highly variable with respect to wetland area, soil organic matter, plant species richness, and species composition. Therefore, it is important to conserve the ciénega landscape as opposed to conserving a single ciénega. Plant species richness is influenced negatively by soil moisture, positively by soil salinity, elevation, and flow gradient (percent slope), and is greater during the post-monsoon season. Despite concerns about woody plant encroachment reducing biodiversity, my investigation suggests canopy cover has no significant influence on ciénega species richness. Plant species community composition is structured by water availability at all ciénegas, which is consistent with the key role water availability plays in arid and semiarid regions. Effects of canopy and salinity structuring community composition are site specific. My investigation has laid the groundwork for ciénega conservation by providing baseline information of the ecology of these unique and threatened systems. The high variability of ciénega wetlands and the rare species they harbor combined with the numerous threats against them and their isolated occurrences makes these vanishing communities high priority for conservation.
ContributorsWolkis, Dustin (Author) / Stromberg, Juliet C. (Thesis advisor) / Hall, Sharon (Committee member) / Salywon, Andrew (Committee member) / Makings, Elizabeth (Committee member) / Arizona State University (Publisher)
Created2016
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Description
Soil organic carbon (SOC) is a critical component of the global carbon (C) cycle, accounting for more C than the biotic and atmospheric pools combined. Microbes play an important role in soil C cycling, with abiotic conditions such as soil moisture and temperature governing microbial activity and subsequent soil C

Soil organic carbon (SOC) is a critical component of the global carbon (C) cycle, accounting for more C than the biotic and atmospheric pools combined. Microbes play an important role in soil C cycling, with abiotic conditions such as soil moisture and temperature governing microbial activity and subsequent soil C processes. Predictions for future climate include warmer temperatures and altered precipitation regimes, suggesting impacts on future soil C cycling. However, it is uncertain how soil microbial communities and subsequent soil organic carbon pools will respond to these changes, particularly in dryland ecosystems. A knowledge gap exists in soil microbial community responses to short- versus long-term precipitation alteration in dryland systems. Assessing soil C cycle processes and microbial community responses under current and altered precipitation patterns will aid in understanding how C pools and cycling might be altered by climate change. This study investigates how soil microbial communities are influenced by established climate regimes and extreme changes in short-term precipitation patterns across a 1000 m elevation gradient in northern Arizona, where precipitation increases with elevation. Precipitation was manipulated (50% addition and 50% exclusion of ambient rainfall) for two summer rainy seasons at five sites across the elevation gradient. In situ and ex situ soil CO2 flux, microbial biomass C, extracellular enzyme activity, and SOC were measured in precipitation treatments in all sites. Soil CO2 flux, microbial biomass C, extracellular enzyme activity, and SOC were highest at the three highest elevation sites compared to the two lowest elevation sites. Within sites, precipitation treatments did not change microbial biomass C, extracellular enzyme activity, and SOC. Soil CO2 flux was greater under precipitation addition treatments than exclusion treatments at both the highest elevation site and second lowest elevation site. Ex situ respiration differed among the precipitation treatments only at the lowest elevation site, where respiration was enhanced in the precipitation addition plots. These results suggest soil C cycling will respond to long-term changes in precipitation, but pools and fluxes of carbon will likely show site-specific sensitivities to short-term precipitation patterns that are also expected with climate change.
ContributorsMonus, Brittney (Author) / Throop, Heather L (Thesis advisor) / Ball, Becky A (Committee member) / Hultine, Kevin R (Committee member) / Munson, Seth M (Committee member) / Arizona State University (Publisher)
Created2019
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Description
The nests of the Curve-billed Thrasher (Toxostoma curvirostre) were studied across the greater Phoenix area from 2020-2022 in order to assess any significant relationships between their composition and the composition of their environment. Nests were collected and measured, and the vegetation was surveyed to 100 m for potential nest material

The nests of the Curve-billed Thrasher (Toxostoma curvirostre) were studied across the greater Phoenix area from 2020-2022 in order to assess any significant relationships between their composition and the composition of their environment. Nests were collected and measured, and the vegetation was surveyed to 100 m for potential nest material type. In the lab, nests were separated by material type and tallied. The dense cores of the nests received a 100-piece sampling, with the first hundred pieces plucked from the structure, sorted by type, and massed. Ordinary least squares (OLS) and binomial regression analyses were performed on the body tallies and their corresponding site tallies. Core material weights and their corresponding site tallies only received OLS regression analyses. Beta regression analyses were also performed on the mass proportions of core samples and their corresponding environmental tallies. OLS regression yielded a significant relationship between the spiny body material tally and its site tallies at 25 and 100 m. While failing the assumption of normality, the tally of barrel cactus in a nest body yielded significant p-values in OLS and binomial regression, as well as the Spearman’s correlation test, supporting a strong correlation with the 100m site tally. The tally of anthropogenic materials and the distance to the nearest man-made structure failed the test of normality, but yielded significant p-values in binomial regression and the Spearman’s correlation test. OLS regression of log anthropogenic tally and log distance to nearest structure failed normality but yielded a significant p-value as well. In beta regression analyses, only the spiny core mass proportion yielded a significant relationship at the 100 m site tally.
ContributorsMotta, Anthony Joseph (Author) / Taylor, Jay (Thesis advisor) / Makings, Elizabeth (Committee member) / Puente, Raul (Committee member) / Arizona State University (Publisher)
Created2022
Description
Urban wetland ecosystems provide myriad ecosystem services and are shaped by diverse social and ecological factors. In rapidly urbanizing parts of the desert Southwest, wetlands are especially vital. Across less than 60 km as it enters the Phoenix area, the Salt River is dammed, diverted, re-filled, clear-cut, restored, and ignored.

Urban wetland ecosystems provide myriad ecosystem services and are shaped by diverse social and ecological factors. In rapidly urbanizing parts of the desert Southwest, wetlands are especially vital. Across less than 60 km as it enters the Phoenix area, the Salt River is dammed, diverted, re-filled, clear-cut, restored, and ignored. This study documents how animal and plant communities in three perennially inundated reaches of the river changed over a decade under different social-ecological pressures. One wetland in the urban core is restored, another formed accidentally by human infrastructure, and the last is managed on the urban periphery. Surveys conducted since 2012 used point-count surveys to assess bird communities and visual encounter surveys to assess reptiles and amphibians. Plant communities were surveyed in 2012 and 2022 using cover classes. Between 2012 and 2022, accidental and restored wetlands close to the urban core displayed an increase in plant abundance, largely consisting of introduced species. While all sites saw an increase in plant species considered invasive by land management groups, both urban wetlands saw an increase in regionally native species, including plants that are culturally significant to local Indigenous groups. Reptile communities declined in richness and abundance in both urban sites, but birds grew in abundance and richness at the urban restored site while not changing at the urban accidental wetland. The non-urban site saw stable populations of both birds and herpetofauna. These trends in biotic communities reveal ecological tradeoffs under different management strategies for urban wetlands. These findings also create a portrait of wetland communities along a rapidly urbanizing arid river. As the Salt River watershed becomes more urbanized, it is important to establish a more empathetic and informed relationship between its plant and animal—including human—residents. To this end, these data were incorporated in a series of handmade paper artworks, crafted from the most abundant wetland plant species found at the study sites, harvested alongside local land management efforts. These artworks examine the potential of four common cosmopolitan wetland plants for papermaking, revealing the potential to align ecosystem management efforts with both materials production and fine arts. By using relief printmaking to visualize long-term ecological data, I explored an alternative, more creative and embodied way to engage with and visualize urban wetland communities. This alternate mode of engagement can complement ecological management and research to diversify disciplines and participants engaged with understanding and living alongside urban wetlands.
ContributorsRamsey-Wiegmann, Luke Dawson (Author) / Childers, Daniel L (Thesis advisor) / Makings, Elizabeth (Committee member) / Bateman, Heather (Committee member) / Arizona State University (Publisher)
Created2023
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Description
Throughout the Southwest, complex geology and physiography concomitant with climatic variability contribute to diverse stream hydrogeomorphologies. Many riparian plant species store their seeds in soil seed banks, and germinate in response to moisture pulses, but the climatic controls of this response are poorly understood. To better understand the

Throughout the Southwest, complex geology and physiography concomitant with climatic variability contribute to diverse stream hydrogeomorphologies. Many riparian plant species store their seeds in soil seed banks, and germinate in response to moisture pulses, but the climatic controls of this response are poorly understood. To better understand the ecological implications of a changing climate on riparian plant communities, I investigated seed bank responses to seasonal temperature patterns and to stream hydrogeomorphic type. I asked the following questions: Are there distinct suites of warm and cool temperature germinating species associated with Southwestern streams; how do they differ between riparian and terrestrial zones, and between ephemeral and perennial streams? How does alpha diversity of the soil seed bank differ between streams with ephemeral, intermittent, and perennial flow, and between montane and basin streams? Do streams with greater elevational change have higher riparian zone seed bank beta-diversity? Does nestedness or turnover contribute more to within stream beta-diversity?

I collected soil samples from the riparian and terrestrial zones of 21 sites, placing them in growth chambers at one of two temperature regimes, and monitoring emergence of seedlings for 12 weeks. Results showed an approximately equal number of warm and cool specialists in both riparian and terrestrials zones; generalists also were abundant, particularly in the riparian zone. The number of temperature specialists and generalists in the riparian zones did not differ significantly between perennial headwater and ephemeral stream types. In montane streams, alpha diversity of the soil seed bank was highest for ephemeral reaches; in basin streams the intermittent and perennial reaches had higher diversity. Spatial turnover was primarily responsible for within stream beta-diversity—reaches had different species assemblages. The large portion of temperature specialists found in riparian seed banks indicates that even with available moisture riparian zone plant community composition will likely be impacted by changing temperatures. However, the presence of so many temperature generalists in the riparian zones suggests that some component of the seed bank is adapted to variable conditions and might offer resilience in a changing climate. Study results confirm the importance of conserving multiple hydrogeomorphic reach types because they support unique species assemblages.
ContributorsSetaro, Danika (Author) / Stromberg, Juliet (Thesis advisor) / Franklin, Janet (Committee member) / Makings, Elizabeth (Committee member) / Arizona State University (Publisher)
Created2016
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Las Cienegas National Conservation Area (LCNCA), located in southeastern Arizona, is a place of ecological and historical value. It is host to rare native, threatened and endangered fauna and flora. as well as the site of the oldest operating ranch in the state. The first chapter of this thesis provides

Las Cienegas National Conservation Area (LCNCA), located in southeastern Arizona, is a place of ecological and historical value. It is host to rare native, threatened and endangered fauna and flora. as well as the site of the oldest operating ranch in the state. The first chapter of this thesis provides a preliminary flora of vascular plants at LCNCA assembled from field collections, photographs and herbarium specimens, and published through the online database SEINet. This preliminary flora of LCNCA identified 403 species in 76 families. Less than 6% of the flora is non-native, perennial forbs and grasses are the most abundant groups, and over a third of species in the checklist are associated with wetlands. LCNCA has been the target of adaptive management and conservation strategies to preserve its biotic diversity, and results from this study will help inform actions to preserve its rare habitats including cottonwood willow forests, mesquite bosques, sacaton grasslands, and cienegas. The second chapter investigates poorly understood aspects of the life history of the endangered Huachuca Water Umbel (Lilaeopsis schaffneriana subsp. recurva. Apiaceae) (hereafter HWU). This wetland species occurs in scattered cienegas and streams in southeastern Arizona and northern Sonora, Mexico. Three studies were conducted in a greenhouse to investigate seed bank establishment, seed longevity, and drought tolerance. A fourth study compared the reproductive phenology of populations transplanted at LCNCA to populations transplanted at urban sites like the Phoenix Zoo Conservation Center and the Desert Botanical Garden (DBG). Results from the greenhouse studies showed that HWU seeds were capable of germinating 15 years in a dormant state and that HWU seeds are present in the seed banks at sites where populations have been transplanted. Also, greenhouse experiments indicated that colonies of HWU can tolerate up to 3 weeks without flowing water, and up to 2 weeks in dry substrate. Transplanted populations at LCNCA monitored in the fourth study produced a higher abundance of flowers and fruit relative to urban sites (i.e. DBG) suggesting that in-situ conservation efforts may be more favorable for the recovery of HWU populations. Findings from these studies aim to inform gaps in knowledge highlighted in USFWS recovery plan for this species.
ContributorsSolves, Jean-Philippe Yvan (Author) / Pigg, Kathleen B (Thesis advisor) / Salywon, Andrew (Committee member) / Makings, Elizabeth (Committee member) / Arizona State University (Publisher)
Created2020