Research

Research 2007 – 2020

My research interests and professional background have concentrated on environmental monitoring and assessment to develop solutions to the ecological restoration and management challenges we face in California and beyond.

I work closely with community partners on outreach for all research projects. Internationally, I have worked for more than ten years with many stakeholders in the documenting, protecting and restoring a critically endangered cypress tree in central Laos. In watersheds of Southern California, I been researching the invasive Arundo donax and native species’ survivorship, phenology, growth, and ecophysiology in large-scale field experiments since 2002. Through this project, I hope to help the regulatory agencies develop performance standards for mitigation projects based in science.

Locally, I am working with the Golden Gate National Recreation Area, conducting a 10-year study of riparian ecosystem recovery through restoration for anadromous Coho salmon and steelhead fish populations in the lower stream reaches of Redwood Creek at Muir Beach. My research employs a variety of study designs and scales to address these environmental questions, using field sampling, lab analyses, GIS analyses, and other technology. I actively engage undergraduate and graduate research students in all my research.

Restoration of Critically Endangered Asian Swamp Cypress Trees of Laos

2014 – 2020

Associate and Assistant Professor, USF.

Funded by grants from the National Geographic Conservation Trust, Chicago Board of Trade, MBZ Species Conservation Fund, and USF Faculty Development Funding.

These grants supported a research team comprised of international researchers, USF students, local government officials, and local University Botany Professor and students. In January and July 2015, we located, measured, and documented almost 600 trees in living stands of the critically endangered cypress (Glyptostrobus pensilis) within the Nakai-Nam Theun National Protected Area (NNT NPA) in Laos. We collected plant tissue for DNA analysis, tree cores to determine the age of trees, other ecological data to help in restoration planning, and seeds to propagate the trees and restore these wetland ecosystems. In 2017, our team documented 200 trees that were cut down by Vietnamese poachers.

In November 2017, IUCN Conifer expert Philip Thomas led an expedition to collect seed from the NNT NPA. We were successful in propagating almost 2,000 seedlings, which was the first time wild seed had been propagated anywhere in the world. In January 2018, Dr. Brendan Buckley of Columbia Universities Tree Ring Lab joined our expedition to take cross section samples from the trees that were felled. On all of our expeditions, our team worked on outreach with wildlife protection authorities and villagers to educate them about the value of conserving these trees for their community.

We also worked with national wildlife protection authorities to develop a concept for outreach to local stakeholders, especially local villagers, about the importance of these trees and the value of conserving them for their community. We produced a 10-minute Glyptostrobus outreach video for local Watershed Management and Protection Authority (WMPA) that will be translated into the Lao language.

We have shown this film to dozens of villagers, government organizations, and other stakeholders in the watershed. I designed and produced a laminated Glyptostrobus information card for government staff and other stakeholders to use in the field and a poster for conservation outreach to be distributed to appropriate villages by WMPA. I helped organize and lead a one-day conservation strategy workshop for WMPA and NTPC Stakeholders in 2017 as well as a Provincial-level restoration workshop in July 2018.


Santa Clara River Riparian Restoration Field Experiment,

2012 – 2020 (funded from 2015 – 2020), Associate and Assistant Professor, USF

Developed and conducted a long-term, large-scale riparian restoration field experiment for the Ventura County Watershed Protection District, working with the River Invasion Research Laboratory at UCSB Marine Science Institute (http://rivrlab.msi.ucsb.edu/index.php). The goal of the study is to investigate native plant species growth, phenology, and ecophysiology under various abiotic conditions found along rivers of Southern California in order to inform performance standards for California Fish and Wildlife Department, State Water Resources Control Board, and US Army Corps of Engineers mitigation plans. Approximately 15 acres of riparian habitat on Ventura County property is being restored between 2012-2017 in three phases (three areas) on property located on the left bank of the Santa Clara River between Fillmore and Santa Paula, California.

A large, highly invasive bamboo-like grass, Arundo donax (Arundo), that I studied for my dissertation research, has been removed from this 15-acre site and another 80 acres on two other sites. An experimental study design was developed and planting was conducted in winter 2016-17. Ten riparian plant species of a diversity of growth forms were planted in experimental restoration sites, in various treatments of soil moisture, irrigation, and light availability. Each summer, we measure plant survivorship, growth, phenology, and ecophysiology (water use efficiency) of native species in this field experiment over the next 10 years.

Redwood Creek Riparian Revegetation Monitoring

2011 – 2020 – Associate and Assistant Professor, USF.

Developed and conducting 10-year study of riparian ecosystem recovery for restoration of anadromous Coho salmon and steelhead fish populations in the lower stream reaches of Redwood Creek at Muir Beach for GGNRA. The project is focused on four primary goals: (1) establishing the revegetation monitoring protocol for vegetation monitoring along nine transects through riparian ecosystems along Redwood Creek for the GGNRA (3 restored, 3 reference, and 3 control transects); (2) understanding the recovery of riparian vegetation after restoration of natural hydrology in a coastal stream of Mediterranean-type climate in California; (3) disseminating results of research and working closely with natural resource manager at GGNRA to inform their management through the use of adaptive management; and (4) helping undergraduate and graduate students learn vegetation sampling skills for further pursuit of their studies or to gain employment in the field of restoration ecology. Sampling has been conducted each summer from 2012 through 2018 by more than 50 graduate and undergraduate students. In addition, two of my graduate students have conducting their thesis research at this site, studying the growth of willow trees planted on the banks of the restored reach inside and outside of deer enclosure fences grown under various soil conditions.

Dune Scrub Restoration Ecology Research on Lone Mountain, San Francisco

2010 – Present, Associate and Assistant Professor, USF.

Worked with USF Landscape Department, Sustainability Coordinator, Director of Operations, and Environmental Science and Studies students to develop a plan to restore approximately half an acre of native dune scrub habitat on the Lone Mountain campus. On December 8, 2012, over 200 native plants of 11 species propagated from San Francisco genetic sources were planted in a 400 ft2 experimental plot in eight treatment blocks, half on a steep slope and half on level ground and with and without irrigation. Fifteen Federally Endangered Franciscan Manzanita were planted and 13 survived.

We hypothesized that plants grown on level ground would result in higher survivorship and growth compared to the steep slope conditions and with irrigation versus unirrigated. Growth metrics measured included five primary factors: height, average width, percent aerial cover, number of flowers, and a non-destructive estimate of biomass. After nine months, overall survivorship was 99%, which indicates that the local native plants were highly successful. On average, survivorship and growth was higher in the flat treatments compared to the slope and in irrigated areas versus non-irrigated. Since this initial planting we have installed over 2,000 native dune plants of 50 species with the Ecosystem Restoration Club members. Results of our monitoring will provide valuable information to inform and encourage future restoration on the USF campus, Presidio of San Francisco, and other coastal dune ecosystem projects in California. We intend to test other important factors, such as light availability and mycorrhizal inoculum treatments, in the next few years of restoration.

Prey Nup Mangroves Restoration Ecology Research

May 2013 – 2015, Assistant Professor, USF

Conducted botanical and restoration ecology reconnaissance surveys at Prey Nup Mangrove Restoration Project in June 2013 and 2014 (http://www.preynupmangrove.com/). Worked with Prey Nup Mangrove organization to commence development of a restoration plan for a portion of 1,000 hectares of mangrove ecosystems protected by this project. Identified 20 mangrove species in the area and sampled the age of eight species. Worked with the project’s conservation manager on a mangrove plant guide for public who will visit the preserve. Met with conservation biology professors from the University of Cambodia in Phnom Penh to work on long-term research planning. A short film was produced on preservation and restoration of mangrove ecosystem at Prey Nup.

San Joaquin River Invasives Project, Central Valley, CA

2012 – 2015
Assistant Professor, USF

Working on the experts’ panel to review work completed by River Partners and The Nature Conservancy biologists. Worked with partners to develop research study design for removal of target invasive plant species on the San Joaquin River. My graduate student conducted her thesis research on control methods for Sesbania punicea.

Riparian Competition Field Experiment, 2002 – 2012, Ecological researcher, UCSB and Assistant Professor, USF.

Research on the large-scale field experiment on the Santa Clara River, Ventura County, CA developed in 2002 investigating factors (nutrients, soil moisture, light, competition with natives) contributing to Arundo donax invasion process in riparian ecosystems of Southern California. More than a dozen field assistants helped resample this experiment in summer 2011. Completed the Santa Clara River Riparian Revegetation and Monitoring Handbook for the Santa Clara River Trustee Council, US Fish and Wildlife Service, and California Department of Fish and Game (July 15, 2011).

Upper Fresno River Watershed Assessment, 2008-2010, Ecological Researcher, WRA.

Developed and directed an invasive plant species program to identify and eradicate/control five target invasive plant species before inundation of the Nakai Plateau. Developed training materials for Lao workers to identify five target species in both English and Lao languages. Trained 30 Lao workers to survey, map using a GPS, and remove/eradicate three of the target species from the 450 km2 project area.

Conducted a watershed assessment study of the Upper Fresno River for the County of Madera funded by a grant from the California Department of Water Resources (Calfed Watershed Program). Aimed to identify and synthesize existing data on key watershed-related issues, including surface water quality, invasive species, and fuels management. Worked with a team of ecologists, wildlife biologists, a GIS specialist, a public involvement specialist, a computer programmer, and hydrologists from WRA and California State University, Fresno. Developed an open-source software internet-based Watershed Portal (http://www.fresnoriver.org/) that allowed agencies, scientists, and the public to access a wide variety of documents, maps, and photos associated with the watershed. Worked with the Technical Advisory Committee and the US Forest Service to develop an invasive plant species community involvement mapping and monitoring program that used the watershed portal for information transfer. Developed land-use GIS predictive model (weighted overlay) focused on stream water quality (nutrients/sedimentation) and invasive species.

Ventura County Historical Ecology Study, 2007 – 2010, Ecological Researcher, UCSB.

Working with a large, multi-disciplinary team of scientists on a historical ecology study of coastal wetlands and river systems in Ventura County, CA for the California State Coastal Conservancy. Facilitated the historical photo and imagery search at the UCSB Map and Imagery Library. Assisting with interpretation of spatial imagery and other historical data to reconstruct the ecology of wetlands and streams for use in County-wide restoration planning.

Wetland Creation for Wildlife in Laos, SE Asia, 2007 – Present, Ecological Researcher, UCSB.

Worked with the director of the Chiang Mai University herbarium conducting floristic surveys to document plant biodiversity and natural wetland/riparian ecosystem processes in the large Nam Theun River floodplain wetland complex on the Nakai Plateau in central Laos, SE Asia. Discovered the only known population of the globally endangered Chinese swamp cypress (Glyptostrobus pensilis) in Laos during these surveys. Worked with a large team of wildlife biologists on development of a mitigation and management plan for the Nakai-Nam Theun National Protected Area as part of the Nam Theun 2 Hydropower Dam project. Designed and implemented a wetland revegetation experiment in 30 wetlands created for wildlife around the reservoir margin including planting transects along an elevation/soil moisture gradient throughout these wetlands. Established long-term revegetation experiments and monitoring sites for evaluation of wetland creation success and effects of dam construction on vegetation on the Plateau. Currently, this is the largest World Bank project in the world, and the first hydropower project in SE Asia to develop environmental standards and implement ecological mitigation.

Invasive Plant Species Control Program, Laos, SE Asia, 2007 – 2009,
Ecological Researcher, UCSB.

Global Comparison of Methane Emissions and Carbon Sequestration from Tropical and Temperate Wetlands: Implications for Climate Change and Wetland Conservation, 2007 – 2009, Ecological Researcher, Ohio State University.

Part of a large team of researchers throughout Asia, Africa, South America, and Central America studying the contribution of methane emissions and carbon sequestration from various wetland ecosystems. The study’s aim is to determine the relative contribution of various types of freshwater wetlands (ranging from degraded to pristine) in temperate and tropical climates to methane emissions and carbon sequestration associated with climate change.