Description: Leaves and woody stems as well as soils and surface waters were collected from two elevational gradient transects across the Coastal and Sierra Nevada Mountains of Northern California. Specimens of Acer macrophyllum, Quercus lobata, Quercus kelloggii, Quercus douglasii, Alnus rubra, Pinus sabineana, Pinus ponderosa, and Pinus jeffreyi were collected during the 2006-growing season. In addition to plant specimens, soil and water samples were collected from plant collection locations along the transect. Here, carbon and hydrogen isotope values of normal-alkanes (n-alkanes), carbon and nitrogen isotope values of bulk leaf material, as well as hydrogen and oxygen isotope values of xylem water are presented from eight co-occurring tree species from ninety-three localities. Carbon and hydrogen isotope values of n-alkanes extracted from soils and hydrogen and oxygen isotope values of surface waters are also presented. Leaf wax n-alkanes were extracted, isolated, identified, and quantified following Tipple and Pagani, 2013 (Geochimica et Cosmochimica Acta, 111, 64-77). The carbon and hydrogen isotope values of leaf wax n-alkanes were conducted following Tipple et al., 2018 (Oecologia, 187, 1053-1075) and Tipple and Pagani, 2013, respectively. The carbon and nitrogen isotope values of leaf materials were measured according to Tipple et al., 2018. Xylem waters were extracted from woody stems and both the hydrogen and oxygen isotope values of xylem and surface waters were measured following Tipple and Pagani, 2013. The purpose of this study was to assess isotope values across steep elevational gradients to better understand the environmental factors and species specific effects responsible for shaping the carbon and hydrogen isotopic compositions of plant materials.

Description: Aquatic and terrestrial plant materials were collected from the Sacramento-San Joaquin Delta region. Carbon and nitrogen isotope values of individual amino acids and bulk materials were measured. Fifty-six specimens were collected from three locations within the Delta, two flooded islands, Mildred and Liberty Islands, as well as an adjacent terrestrial riparian habitat (Big Break Regional Shoreline). Specimens included terrestrial trees, shrubs, forbs, and grasses as well as floating, submerged, and emergent aquatic plants. Bulk leaf tissues were processed and the carbon and nitrogen isotope values of bulk tissues were measured following Tipple and Ehleringer, 2018 (Oecologia, 187, 1053-1075). Amino acids were hydrolyzed, derivatized, and isolated following Vokhshoori et al., 2013 (Marine Ecology Progress Series, 504, 59-72). Carbon and nitrogen isotope values of individual amino acids were measured following Vokhshoori et al., 2013 and Vokhshoori and McCarthy, 2013 (PLoS ONE, 9, 6, e98087), respectively. The purpose of this research was to create a novel molecular isotope toolset to increase the understanding of biogeochemistry and food web structure of the Sacramento-San Joaquin Delta's tidal wetlands and estuarine marshes.

Description: Aquatic and terrestrial plants were collected from the Sacramento-San Joaquin River Delta. Nitrogen isotope values of bulk plant tissue and individual amino acids were measured. Fifty-six specimens from thirty-nine native, introduced and invasive species were collected. Growth forms and habits include trees, shrubs, forbs, and grasses as well as floating, submerged, and emergent aquatic plants. Bulk tissues were processed and the nitrogen isotope values were measured following Tipple and Ehleringer, 2018 (Oecologia, 187, 1053-1075). Amino acids were hydrolyzed, derivatized, and the carbon isotope values of individual amino acids were measured following Vokhshoori and McCarthy, 2013 (PLoS ONE, 9, 6, e98087). The purpose of this study was to assess trophic discriminate factors at the base of estuarine systems with multiple primary producers. This study provides an authentic dataset of primary producers for trophic position assessments in estuarine and mixed terrestrial-marine source environments.

Description: Plant material was collected from aquatic and terrestrial environments from the Sacramento-San Joaquin River Delta. Carbon isotope values of bulk plant tissue and individual amino acids were measured. Fifty-five specimens were collected, including trees, shrubs, forbs, and grasses as well as floating, submerged, and emergent aquatic plants. Bulk tissues were processed and the carbon isotope values were measured following Tipple and Ehleringer, 2018 (Oecologia, 187, 1053-1075). Amino acids were hydrolyzed, derivatized, and isolated following Vokhshoori et al., 2013 (Marine Ecology Progress Series, 504, 59-72). Carbon isotope values of individual amino acids were measured following Vokhshoori et al., 2013. The purpose of this study was to assess if amino acid fingerprints of macrophyte primary producers were distinct from those of marine primary producers and terrestrial vascular plant species. The goal of this study was to provide a benchmark dataset for the next generation of food web monitoring programs within estuarine and mixed source environments.

Description: Tap waters were collected from major metropolitan areas of the western United States. Tap waters were sampled between 2012-2015 from seven metropolitan areas: Los Angeles-Long Beach-Santa Ana (CA), Phoenix-Mesa-Glendale (AZ), Salt Lake City (UT), San Diego-Carlsbad-San Marcos (CA), San Francisco-Oakland-Fremont (CA), San Jose-Sunnyvale-Santa Clara (CA), and Riverside-San Bernardino-Ontario (CA). These areas represent some of the most populous in the US and employ a diversity of water management practices. Here hydrogen (d2H) and oxygen (d18O) isotope values along with strontium isotope ratios (87Sr/86Sr) and element abundances were measured. d2H and d18O of 2039 tap waters were measured following Tipple et al., 2017 (Water Research, 119, 212-224). 87Sr/86Sr and elemental compositions of 820 and 806 waters were analyzed following Tipple et al., 2018 (Scientific Reports, 8, 2224), respectively. The purpose of these data was to assess spatial, temporal, and climatic dynamics in isotope and elemental geochemistry of tap waters. We found that the isotope and elemental geochemistry of tap waters corresponded to the water sources (e.g., transported water, local surface water, groundwater, etc.) and management practices (e.g., storage in open reservoirs, mixing, etc.) for discrete areas within the larger metropolitan areas.