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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.
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.
of community associations of plants in a region. Also, a region’s floristic analysis is key not only to investigating their geographical origin(s) but is necessary to their management and protection as a reservoir of greater biodiversity. With an area of 2,250,000 square kilometers, the country of Saudi Arabia covers almost four-fifths of the Arabian Peninsula. Efforts to document information on the flora of Saudi Arabia began in the 1700s and have resulted in several comprehensive publications over the last 25 years. There is no doubt that these studies have helped both the community of scientific researchers as well as the public to gain knowledge about the number of species, types of plants, and their distribution in Saudi Arabia. However, there has been no effort to use digital technology to make the data contained in various Saudi herbarium collections easily accessible online for research and teaching purposes. This research project aims to develop a “virtual flora” portal for the vascular plants of Saudi Arabia. Based on SEINet and the Symbiota software used to power it, a preliminary website portal was established to begin an effort to make information of Saudi Arabia’s flora available on the world- wide web. Data comprising a total of 12,834 specimens representing 175 families were acquired from different organizations and used to create a database for the designed website. After analyzing the data, the Fabaceae family (“legumes”) was identified as a largest family and chosen for further analysis. This study contributes to help scientific researchers, government workers and the general public to have easy, unlimited access to the plant information for a variety of purposes.
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.
The climate conversation is growing more important and necessary than ever. The media has a way of promoting a "doom and gloom" sentiment over conservation efforts and what the public has the power to do in terms of making a change. Now due to the effects of COVID-19 on the population's attention spans and memories, there is a need for a way to communicate climate science effectively and to encourage those who feel discouraged by climate change to find their inner power. The answer lies in photography. Making science accessible and intriguing through the art of photography is what can get people more interested and empowered to fight against climate change and alter their attitudes towards environmentalism. This thesis explains psychological research and the reasons why people feel helpless in terms of our global future. In then dives into human subjects research conducted on ASU's campus and how the survey results argue in favor of the paper's hypothesis. Additionally, ways to get involved and reasons why we need to remain hopeful are discussed.
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.