Habitat area can be a proxy for population size (Turlure et al., 2010). As with aquatic diversity metrics, additional sustainability indicators for terrestrial biodiversity might be obtained from recovery plans for species listed under the Endangered Species Act (Table 5-9).
For wildlife exposures to salinity and contaminants in drinking water, sustainability indicators would include:
• Dosage received by wildlife (direct measure).
• Number of vertebrate fatalities from drinking from algal ponds per year (direct measure).
• Concentrations of toxicants, toxins, or salinity in culture medium (less direct measure).
• Abundance of vertebrates drinking from open ponds per year (less direct measure).
5.7.5 Information and Data Gaps
Patterns of development of algal biofuel facilities in relation to wildlife corridors have not been studied because locations for future development are uncertain. The spatial scale and landscape pattern of these developments needs to be understood to simulate the effects on wildlife populations. As algae cultivation expands in number and scale, the potential for wildlife drinking needs to be assessed at sites. If wildlife drinking is observed, then concentrations of toxicants in source waters and culture waters need to be measured to ensure that there is no threat to wildlife health. Alternatively, measures to deter wildlife drinking can be implemented.
5.8.1 Potential Environmental Effects
The environmental sustainability of genetically engineered feedstocks for bioenergy (Wolt, 2009; Moon et al., 2010) and the potential implications of regulations on sustainable development of the industry (Moon et al., 2010; Strauss et al., 2010) have been considered previously, but the emphasis has been on engineered terrestrial crops (Moon et al., 2010) rather than algae. Some algal biofuel companies, such as Algenol and Synthetic Genomics, are conducting research on genetically engineered organisms for algal biofuel production (Gressel, 2008). In a hypothetical, worst-case scenario, genetically engineered algae that have been introduced to natural environments might persist and become so abundant that they create harmful algal blooms (Snow and Smith, 2012). Clearly, any adverse effects of released genetically engineered algae, if observed, would affect the sustainable development of algal biofuel technologies. The evaluation of potential effects of genetically engineered algae will be a complex undertaking, given the diversity of organisms, range of engineered functions, and range of environments potentially receiving the engineered organisms (Tiedje et al., 1989). This section of the report addresses the novel traits and genetic structure of genetically engineered cyanobacteria and microalgae for biofuels and whether they have unique or more uncertain risks. (Potential genetic manipulation methods are discussed in Chapter 2.)
Past broad assessments of the risks of genetically engineered organisms have concluded that the product (novel traits) is more important than the process (genetic engineering techniques) for evaluating risk (NRC, 1987; Tiedje et al., 1989; Snow et al., 2005). However, novel traits may be more common when the process for creating new algae involves direct genetic manipulation than when horizontal gene transfer occurs in evolutionary time.