Dissertation/Thesis Abstract

Foodweb Dynamics in Shallow Tidal Sloughs of the San Francisco Estuary
by Montgomery, Jacob R., M.S., University of California, Davis, 2017, 110; 10620274
Abstract (Summary)

Non-parametric ANOVA tests, ordination, and Bayesian generalized linear models (GLMs) revealed strong physical, chemical, and biological differences among the study sites. Lower trophic foodweb indexes (i.e., chlorophyll-a (chl-a) concentration, zooplankton biomass, and planktivorous fish abundance) were investigated in association with environmental variables in three terminal sloughs within the upper San Francisco Estuary. Non-metric multidimensional scaling (NMDS) showed tight clustering of data from each site. Kruskal-Wallis tests confirmed the NMDS by identifying statistically-significant differences among sites and between paired sites within each of the three regions (i.e., Cache Slough, Lindsey Slough, Suisun Marsh). Bayesian GLMs identified temperature and dissolved inorganic nitrogen as primary correlates with chl-a concentration, and temperature and chl-a concentration as primary correlates with zooplankton biomass. Planktivorous fish data were insufficient to fit a GLM. Up-slough sites in Cache Slough and Suisun Marsh consistently showed greater abundances of chl-a and zooplankton relative to down-slough sites in each region. However, that pattern was reversed in Lindsey Slough. Possible reasons for this discrepancy include adjacent land-use and management practices, relative importance of alternate foodweb pathways, and the presence of a major water diversion. This study emphasizes the importance of site-specific foodweb dynamics and local anthropogenic effects, particularly in relation to design of tidal wetland restoration projects.

Indexing (document details)
Advisor: Moyle, Peter B.
Commitee: Dahlgren, Randy A., Sommer, Ted
School: University of California, Davis
Department: Ecology
School Location: United States -- California
Source: MAI 57/01M(E), Masters Abstracts International
Subjects: Ecology, Natural Resource Management, Aquatic sciences
Keywords: Aquatic ecosystem management, California, Novel ecosystem, Restoration, Terminal slough, Tidal wetland, Zooplankton
Publication Number: 10620274
ISBN: 9780355461657