Research Projects

Restoration of Critically Endangered Chinese Swamp Cypress Trees of Laos

Assistant Professor, USF

Awarded a one-year grant from a National Geographic Conservation Trust to support a team of international researchers and USF students to locate, measure, and document known living stands of Glyptostrobus pensilis or Chinese swamp cypress within the Nakai-Nam Theun National Protected Area (NNT NPA) in Laos in August 2014 and January 2015. Chinese swamp cypress is critically endangered globally and almost extinct in the wild with only 250 trees documented in two small stands in coffee plantations in Vietnam ( We will collect plant material for DNA analysis and seeds to propagate the trees and restore cypress populations to wetland ecosystems in the NNT NPA. The team is working with wildlife protection authorities and villagers to educate them about the value of conserving these trees for their community. We are conducting species habitat modeling using the GIS Maxent model (maximum-entropy approach). We have input layers of environmental variables (such as elevation, precipitation, soils etc.), as well as a set of georeferenced occurrence locations of the cypress, and produced a model of the potential range of the cypress in our NNT NPA which we will use to locate other stands as well as locations for their restoration. Partners include: Royal Botanical Garden Edinburgh, San Francisco Botanical Garden, Pha Tad Ke Botanical Garden, Laos, Laos Wildlife Association, and the NNT NPA Watershed Management Protection Agency. May 2014 – present.

Prey Nup Mangroves Restoration Ecology Research

Assistant Professor, USF

Conducted botanical and restoration ecology reconnaissance surveys at Prey Nup Mangrove Restoration Project in June 2013 and July 2014 ( Worked with Prey Nup Mangrove organization to begin to develop a restoration plan for a portion of 1,000 hectares of mangrove ecosystems protected by this project. Identified over 30 mangrove species in the area and sampled age of 8 species. Worked with the project’s conservation manager on a mangrove plant guide for public who will visit the preserve and with conservation biology Professors from the Royal University of Phnom Penh as project partners. Planning next research trip for June 2015 to document all mangrove plant species throughout the project area, develop a conceptual restoration plan, helping to write grants for building an information center and for ecosystem restoration, and plan to teach a service learning Field Botany course at the project for the Royal University of Phnom Penh. This project supported one master’s student research assistant for the last two years. May 2013 – present.

Riparian Restoration Field Experiment along Santa Clara River

Assistant Professor, USF

Developed long-term, large-scale riparian restoration field experiment for the Ventura County Watershed Protection District (VCWPD). The goal of the study is to investigate native plant species growth and phenology 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 will be restored between 2012-2014 in three phases (3 areas) on property located on the left bank of the Santa Clara River between Fillmore and Santa Paula, CA. Initial removal of invasive Arundo donax was conducted on a 5 acres parcel in February 2012, 5 more acres in fall 2013, and another 5 acres was just removed in fall 2014. Experimental study design planting will begin in winter 2014 in the first removal area. In December 2014, we will install groundwater monitoring wells throughout the site. 20 plant species will be planted in experimental restoration sites, in various treatments of soil moisture/irrigation and light availability. Students in my research lab will work with student aids from the VCWPD and students and researchers from UCSB RIVRLAB to measure plant growth, phenology, and ecophysiology metrics in this field experiment from 2014-2024. We are partnering with the RIVRLAB ( at UCSB on their adjacent 100 acre experiment. 2012 – present.

Muir Woods Riparian Dendrochronology Study

Assistant Professor, USF

Conducted a riparian dendrochronology tree survey along Redwood Creek in Muir Woods National Monument for Golden Gate National Recreation Area. The goal of our sampling was to provide the restoration team tree ages on seven floodplain terraces along the project reach in order (1) to evaluate how this reach of the creek has evolved and migrated in the historic period in response to human interventions and natural processes, and (2) to better understand how it is expected to change in the future. Three tree species were sampled including, California bay laurel (Umbellularia californica), red alder (Alnus rubra), and big leaf maple (Acer macrophyllum). We measured the diameter at breast height (DBH) of 74 individual trees and cored 15 trees between 30 and 60 cm using an 18-inch increment borer. We found a very strong relationship between the number of rings counted and DBH for California bay core samples, with a R2 value of 0.9635. California bay laurel trees were used to determine the age of the Redwood Creek floodplains since this species was common along Redwood Creek study reaches, and the regression model explained more of the variability of the response data around its mean than either of the other species. The tree ages will help provide the ecologic basis for defining appropriate creek setbacks for planned parking structures. This project has and continues to support graduate and undergraduate students (5 students to date). Summer 2013 – present.

Dune Scrub Restoration Ecology Research on Lone Mountain, San Francisco

Assistant Professor, USF

Worked with USF Landscape Department and Environmental Science students to develop a plan to restore approximately one 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. We hypothesized that plants grown on level ground would result in higher survivorship and growth compared to the steep slope conditions. Growth metrics measured included: height, average width, percent aerial cover, number of flowers, and a non-destructive estimate of biomass. We measured plant survivorship and growth metrics after the initial installation and at the end of the first growing season. 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. Our results 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. 2010 – present.

Redwood Creek Riparian Revegetation Monitoring

Assistant Professor, USF

Developed and conducting 20 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. Project goals include: (1) establishing the revegetation monitoring protocol for vegetation monitoring along 9 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 California; (3) disseminating results of research and working closely with natural resource manager at GGNRA to inform their management through adaptive management; and (4) to help 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 was conducted in July-September 2011-2014 with 8 undergraduate students and 16 masters students. Also, two masters students whom I advise are 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 exclosures grown under various soil conditions. 2010 – present.

San Joaquin River Invasives Project, Central Valley, CA

Assistant Professor, USF

Working on the experts panel to review work completed by biologists from River Partners (, The Nature Conservancy, and the San Joaquin River Parkway and Conservation Trust ( Worked with partners to develop research study design for removal of target invasive plant species on the San Joaquin River. Study is being implemented in 2013-2015. USF graduate students are helping with data collection. This project supports my current Masters Thesis student who is conducting her research on the control of red sesbania (Sesbania punicea) soil seed banks using solarization in restored reaches of the San Joaquin River. 2012 – present.

Arundo donax Fire Studies

Graduate student researcher, UCLA and ecological researcher, UCSB

Documented the influence of Arundo donax on spread of fire in riparian ecosystems adjacent to shrublands of the Santa Clara River watershed, Ventura County, CA. Collected historical GIS fire data, recent Arundo donax mapping data, and demographic data for the Santa Clara River watershed.  Mentored environmental science graduate student from the Hebrew University, Israel and UCLA undergraduate independent research students assisting with field and GIS work.  Funded by UC Center for Water Resources and CA Coastal Conservancy. 2003-Present

Riparian Competition Field Experiment

Ecological researcher, UCSB

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: Santa Clara River Trustee Council, US Fish and Wildlife Service and California Department of Fish and Game (July 15, 2011). 2007-Present.

Upper Fresno River Watershed Assessment

Ecological researcher, WRA

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).  Aims to identify and  synthesize existing data on key watershed-related issues, including: surface water quality, invasive species, and fuels management.  Working with a team of ecologists, wildlife biologists, GIS specialist, public involvement specialist, computer programmer, and hydrologists from WRA and California State University, Fresno.  Developed an open source software internet-based Watershed Portal ( that allows agencies, scientists, and the public to access a wide variety of documents, maps, and photos associated with the watershed.  Working with the Technical Advisory Committee and the US Forest Service to develop an invasive plant species community involvement mapping and monitoring program that uses the watershed portal for information transfer.  Developing land use GIS predictive model (weighted overlay) focused on stream water quality (nutrients/sedimentation) and invasive species. 2008-2010.

Ventura County Historical Ecology Study

Ecological researcher, UCSB

Worked 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.  2007-present.

Wetland Creation for Wildlife in Laos, SE Asia

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 of on 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 with 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 globally and the first hydropower project in SE Asia to develop environmental standards and implement ecological mitigation.  2007-present.

Invasive Plant Species Control Program, Laos, SE Asia

Ecological researcher, UCSB

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 kmproject area. 2007-2009.

Global Comparison of Methane Emissions and Carbon Sequestration from Tropical and Temperate Wetlands: Implications for Climate Change and Wetland Conservation

Ecological researcher, UCSB

Part of a large team of researchers including The Ohio State University 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 (degraded to pristine) in temperate and tropical climates to methane emissions and carbon sequestration associated with climate change. 2007-present.