NASA Ames Research Center – DRAAWP Areas of Focus
David Bubenheim, NASA-ARC, email@example.com
NASA Ames Research Center (NASA-ARC) is a partner with other DRAAWP members in developing science-based, adaptive-management strategies for aquatic invasive weeds in the California Sacramento-San Joaquin River Delta. Changes in climate, long-term drought, and water quality are all suspected of playing roles in the dramatic expansion of invasive aquatic plants and their impact on ecosystems of the San Francisco Bay / California Delta complex. In developing management strategies, it is critical to understand how the Delta is affected by human use and by changes induced by drought or climate shifts. We also need to understand how the plants respond to these altered environments.
NASA is applying remote sensing and modeling technologies to provide aquatic weed mapping, assess the scope and potential impact of weeds, and provide decision support tools for selection of short and long-term management practices. NASA supplies strategic mapping and assessment information to assist Delta weed management teams in the present, and develops information which can be used to build strategic management plans.
Aquatic Weed Mapping - An early product developed by NASA-ARC is a Water Hyacinth Mapping Tool. The satellite-based tool provides water hyacinth distribution maps and tabular reporting of coverage areas in specific waterways throughout the Delta at 14-day intervals. The mapping tool is currently being validated by the DRWAAP team and utilized by the California Department of Boating and Waterways (CA-DBW) to analyze hyacinth movement, direct hyacinth control teams, and assess control treatment effectiveness. Submerged aquatic weeds cannot be mapped using the same satellite as the water interferes with spectral reflectance measurements. Submerged weed mapping tools are being developed using other remote sensing platforms.
Watersheds and Water Quality in the Delta. Land use both in the Delta and in upstream watersheds has an influence on water quality.
We use the Soil Water Assessment Tool (SWAT), a watershed-scale model developed by USDA-ARS, to evaluate the impact of land management practices in large and complex watersheds on the quality and quantity of water entering the Delta. The model uses land-use patterns, soils, elevation, and hydrologic routing to characterize pesticide and nutrient transport from the Sacramento and San Joaquin river watersheds into the Delta. A customized Delta model based on SWAT, Delta-SWAT, has been developed to evaluate land use within the Delta, as well as water extraction to supply those functions, and the resulting return of water to Delta waterways. Delta-SWAT water quality trend estimates are compared with water quality monitoring conducted throughout the Delta.
Gap-Filling Science. A significant gap in relevant science involves understanding how important native and invasive aquatic plants respond to the altered environmental conditions of the Delta. NASA-ARC uses unique controlled environment facilities to define plant response to relevant environmental conditions at time scales appropriate for characterizing response in the Delta. These parameters of response for aquatic plants to water quality (nutrients and contaminants), temperature and light are used to drive a customized model that operates with Delta-SWAT. Plant response can be predicted and so risk of invasive aquatic weed growth can be determined as a result of environmental changes driven by human activities or other sources.
Decision Support Tools – Delta-SWAT provides a tool for evaluating temporal and spatial effects of land-use and altered environments in the Delta and contributing watersheds on aquatic weed growth. Using Delta-SWAT for simulation modeling allows evaluation of historic and current conditions as well as consideration of future potential climate change. Inclusion of management practice (biological, chemical, mechanical, others) impacts on invasive aquatic weeds and associated resources and costs required for specific practices, provides a basis for evaluating management practice outcomes. Delta-SWAT adds to the scientific understanding of dynamics in the Delta and enhances development of science-informed, management strategies and practices.
The project combines the science, operations, and economic implications related to various scenarios for integrated management of aquatic weeds in the Delta to help land and waterway managers make science-informed decisions regarding management and outcomes. Methods developed by the project can become routine land and water management tools. New high-resolution NASA sensor systems could provide standard data packages specifically designed for water system and ecosystems assessment and management. These methods developed and demonstrated in the California Delta may provide a template for improved management of resources in complex river delta systems worldwide.