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The DOE-OBP Multi-year Program Plan (MYPP) biomass production targets are 44 million dry tons per year by 2012 and 155 million dry tons per year by 2017 (EERE Biomass Program, 2011). Macroalgae, more commonly known as seaweed, could be a significant biomass resource for the production of biofuels. The overall project objective is to conduct a strategic analysis to assess the state of macroalgae as a feedstock for biofuels production. To this end, this project provides an assessment of the potential for domestic macroalgae production and identifies the key technical issues associated with the feasibility of using macroalgae resources. Work began in FY10 as a screening analysis of the key questions related to the status of macroalgae as a feedstock resource. These efforts addressed the state of technology, types of fuels possible, a rough order-of-magnitude resource assessment, and preliminary high-level economic analysis, resulting in a Summary Report entitled Macroalgae as a Biomass Feedstock: A Preliminary Analysis (PNNL-19944).While considerable progress has been made in developing and applying GIS-based spatiotemporal models of high granularity to siting microalgal growth facilities in terrestrial landscapes in the continental U.S. (Wigmosta et al., 2011), parallel efforts to identify suitable sites for macroalgal cultivation in U.S. marine waters have yet to be reported. Such effort requires development of new analysis tools because those developed for land-based microalgal resources (Wigmosta et al., 2011) are not directly applicable to marine waters. Thus, the plan for subsequent years, starting in FY11, was to develop a multi-year systematic national assessment to evaluate the U.S. potential for macroalgae production using a GISbased assessment tool and biophysical growth model developed as part of these activities. The broad goal of this modeling effort is to develop a National Macroalgae Assessment Model for evaluating macroalgae production in marine waters within the U.S. Exclusive Economic Zone (EEZ). Focus was placed on an assessment of kelp, a group of brown macroalgae considered suitable for conversion to biofuels based on biochemical composition and growth characteristics. Progress in FY11, which focused on model development and initial application of the models to demonstration areas in offshore waters, is described in this report.During FY11, a concept map describing spatial models to identify suitable sites for producing macroalgae biomass was developed as a framework for conducting a GIS-based national resource assessment within the U.S. EEZ. The spatial models included modeling macroalgae production potential, constrained by competing uses and legal, environmental, and infrastructure considerations at specified locations in the U.S. EEZ. A literature review of these constraints was conducted, and remotely-sensed data sources were identified, downloaded, and processed using 8-day composites from 2000 to 2011 to support site screening and macroalgae growth model development. Model demon...

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Estuarine ecosystems are largely influenced by watersheds directly connected to them. In the Mobile Bay, Alabama watersheds we examined the effect of land cover and land use (LCLU) changes on discharge rate, water properties, and submerged aquatic vegetation, including freshwater macrophytes and seagrasses, throughout the estuary. LCLU scenarios from 1948, 1992, 2001, and 2030 were used to influence watershed and hydrodynamic models and evaluate the impact of LCLU change on shallow aquatic ecosystems. Overall, our modeling results found that LCLU changes increased freshwater flows into Mobile Bay altering temperature, salinity, and total suspended sediments (TSS). Increased urban land uses coupled with decreased agricultural/pasture lands reduced TSS in the water column. However, increased urbanization or agricultural/ pasture land coupled with decreased forest land resulted in higher TSS concentrations. Higher sediment loads were usually strongly correlated with higher TSS levels, except in areas where a large extent of wetlands retained sediment discharged during rainfall events. The modeling results indicated improved water clarity in the shallow aquatic regions of Mississippi Sound and degraded water clarity in the Wolf Bay estuary. This integrated modeling approach will provide new knowledge and tools for coastal resource managers to manage shallow aquatic habitats that provide critical ecosystem services.

Executive SummaryThe purpose of this study was to evaluate the ability to enhance distribution of eelgrass (Zostera marina) in the Columbia River Estuary to serve as refuge and feeding habitat for juvenile salmon, Dungeness crab, and other fish and wildlife. We strongly suspected that limited eelgrass seed dispersal has resulted in the present distribution of eelgrass meadows, and that there are other suitable places for eelgrass to survive and form functional meadows.Funded as part of the Bonneville Power Administration's call for Innovative Projects, we initiated a multistage study in 2008 that combined modeling, remote sensing, and field experimentation to:1. Spatially predict habitat quality for eelgrass.2. Conduct experimental plantings. Evaluate restoration potential.Baseline in-situ measurements and remote satellite observations were acquired for locations in the Lower Columbia River Estuary (LCRE) to determine ambient habitat conditions. These were used to create a habitat site-selection model, using data on salinity, temperature, current velocity, light availability, wave energy, and desiccation to predict the suitability of nearshore areas for eelgrass. Based on this model and observations in the field, five sites that contained no eelgrass but appeared to have suitable environmental conditions were transplanted with eelgrass in June 2008 to test the appropriateness of these sites for eelgrass growth. We returned one year after the initial planting to monitor the success rate of the transplants. During the year after transplanting, we carried out a concurrent study on crab distribution inside and outside eelgrass meadows to study crab usage of the habitat.One year after the initial transplant, two sites, one in Baker Bay and one in Young's Bay, had good survival or expansion rates with healthy eelgrass. Two sites had poor survival rates, and one site had a total loss of the transplanted eelgrass. For submerged aquatic vegetation (SAV) restoration projects, these are reasonable success results and represent a small net gain in eelgrass in the LCRE. Crabs used both the eelgrass and unvegetated substrate, though in neither were there great abundance of the young-of-the-year crabs. During the field assessment of 12 potential transplant sites, divers discovered one site in southern Young's Bay that contained a previously undocumented eelgrass bed.This integrated project developed the first predictive maps of sites suitable for eelgrass and other SAV in the lower estuary. In addition, techniques developed for this project to assess light levels in existing and potential submerged habitats have great potential to be used in other regions for nearshore and coastal monitoring of SAV.Based on these preliminary results, we conclude that eelgrass distribution could likely be expanded in the estuary, though additional information on current eelgrass locations, usage by species of interest, and monitoring of current conditions would help develop a baseline and verify benefit. Our recommendations for future studies i...