Award Date

12-15-2025

Degree Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Environmental and Global Health

First Committee Member

Mark P. Buttner

Second Committee Member

Patricia Cruz

Third Committee Member

Miguel Antonio Fudolig

Fourth Committee Member

Kavita Batra

Number of Pages

111

Abstract

Airborne pollen are a predominant cause of asthma, allergic disease, and respiratory infections. The strong allergenic potential of tree pollen is of a public health concern. Several allergenic trees grow in the Mojave Desert, but not all are native to the region. Concentrations of airborne tree pollen are affected by atmospheric, environmental, ecological, and geospatial factors. Previous research has reported high tree pollen concentrations in the Las Vegas Valley, but long-term comparison studies are lacking. This study measured and compared tree pollen concentrations from five different collection stations in Las Vegas. Pollen samples collected from January 1, 2017, to December 31, 2021, were analyzed for the most abundant and allergenic tree pollen taxa (Fraxinus, Morus, Olea, Pinus, and Platanus). Time-series analysis was performed on the datasets. An autoregressive integrated moving average (ARIMA) analysis was used to model how tree pollen counts may differ across different time periods and locations in the Las Vegas Valley. Models were robust for Fraxinus, Olea, and Pinus across all sites (P > 0.05). At Sunrise Acres (SA), residual autocorrelation persisted for Morus and Platanus (P < 0.05). Significant differences were observed in the concentrations of individual tree species and seasonal/annual variances among the five sites from 2017 to 2021. Morus was the dominant tree pollen at all sites. The time series distribution at each location did not show significant differences over time for Fraxinus, Morus, and Platanus. Pairwise post hoc tests for Olea and Pinus showed significant differences in all years except 2017 and 2020 at the Joe Neal (JN) and Palo Verde (PV) collection sites, and at Jerome Mack (JM), JN, PV, and SA sites across all years (P < 0.05), respectively. Significant differences in time series distributions were observed across sites for Fraxinus (PV vs. SA, PV vs. UNLV), Morus (PV vs. UNLV), Pinus (JN vs. SA), and Platanus (JM vs. UNLV, SA vs. UNLV). The results indicate that interconnected environmental conditions and species-specific ecological impacts exist. Long-term monitoring is required to capture more complete temporal trends.

Keywords

Aeroallergen Monitoring; ARIMA; Spatial Comparion; Temporal Comparison; TIME series analysis; Tree Pollen

Disciplines

Environmental Sciences | Other Environmental Sciences | Physical Sciences and Mathematics

File Format

PDF

File Size

1402 KB

Degree Grantor

University of Nevada, Las Vegas

Language

English

Rights

IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/

Download


Share

COinS