Nannochloropsis salina with nitrate as a nitrogen source, elevated N 2 O emissions
were observed under a nitrogen headspace (photobioreactor simulation) during dark
periods, but N 2 O emissions were low during light periods. Proper management of
the algae biofuel production systems, which would prevent senescence of algae and
maintain aerobic conditions in ponds, likely would keep N 2 O emissions to low
levels.
1.6.4 Aquatic and Terrestrial Biodiversity
Microalgae are cosmopolitan in their biogeographical distributions and therefore
they have their broad habitat range. However, they are not necessarily found in every
location so their distribution is often mosaic-like (Hoffmann 1996). Coastal marine
macroalgae inclined to less distributed than microalgae and phytoplanktonic forms.
Macroalgae have restricted range of temperature, light, substratum, and nutrient
preferences. Whitford (1983) explains that species of freshwater algae may appear
to be infrequent for several reasons and this suggests that few rare species of algae
could be displaced by invasive algae used to produce biofuel feedstocks. For biofuel
production from algae, open culture system in natural environment such as open
ponds system is very common. Release may occur during the feedstock production
stage or possibly during the harvesting or drying stages. Characteristics like rapid
growth, vegetative propagation, pest resistance can make algal species desirable for
the production of biofuel. In open pond system, several exotic species could disturb
the coherence of local and regional ecosystems (Ryan 2009a, b).
The outline of landscape conversion for any new setup could affect terrestrial
species diversity through three distinct mechanisms that not only apply for production of algal biofuel but also for other energy production (McCabe 1994; DOE 2009;
Garvin et al. 2011).
(1) Movement of terrestrial vegetation and wildlife habitat from the facility area
and replacement with a pond or photobioreactor containing a monoculture or a few
species of algae. (2) Reduction in local wildlife habitat area below the threshold
which will be needed for the species. (3) Fragmentation of wildlife habitat and
migration corridors should be disrupted. The magnitude of land requirements and the
types of conversions affect the magnitude of probable effects on ecological
populations and communities. There are some studies that focus primarily on
terrestrial ecosystems and terrestrial plant biofuel feedstocks, rather than on aquatic
systems and algal feedstocks (Fargione et al. 2009; Fletcher et al. 2011; Wiens et al.
2011).
1.6.5 Effect of Genetically Modified Organisms
The sustainability goals for genetically engineered algae likely would include two
other issues: (1) to minimize dissemination of genetically engineered algae (2) an
establishing method to determine whether an observed effect was caused by a
20
N. Maheshwari et al.
were observed under a nitrogen headspace (photobioreactor simulation) during dark
periods, but N 2 O emissions were low during light periods. Proper management of
the algae biofuel production systems, which would prevent senescence of algae and
maintain aerobic conditions in ponds, likely would keep N 2 O emissions to low
levels.
1.6.4 Aquatic and Terrestrial Biodiversity
Microalgae are cosmopolitan in their biogeographical distributions and therefore
they have their broad habitat range. However, they are not necessarily found in every
location so their distribution is often mosaic-like (Hoffmann 1996). Coastal marine
macroalgae inclined to less distributed than microalgae and phytoplanktonic forms.
Macroalgae have restricted range of temperature, light, substratum, and nutrient
preferences. Whitford (1983) explains that species of freshwater algae may appear
to be infrequent for several reasons and this suggests that few rare species of algae
could be displaced by invasive algae used to produce biofuel feedstocks. For biofuel
production from algae, open culture system in natural environment such as open
ponds system is very common. Release may occur during the feedstock production
stage or possibly during the harvesting or drying stages. Characteristics like rapid
growth, vegetative propagation, pest resistance can make algal species desirable for
the production of biofuel. In open pond system, several exotic species could disturb
the coherence of local and regional ecosystems (Ryan 2009a, b).
The outline of landscape conversion for any new setup could affect terrestrial
species diversity through three distinct mechanisms that not only apply for production of algal biofuel but also for other energy production (McCabe 1994; DOE 2009;
Garvin et al. 2011).
(1) Movement of terrestrial vegetation and wildlife habitat from the facility area
and replacement with a pond or photobioreactor containing a monoculture or a few
species of algae. (2) Reduction in local wildlife habitat area below the threshold
which will be needed for the species. (3) Fragmentation of wildlife habitat and
migration corridors should be disrupted. The magnitude of land requirements and the
types of conversions affect the magnitude of probable effects on ecological
populations and communities. There are some studies that focus primarily on
terrestrial ecosystems and terrestrial plant biofuel feedstocks, rather than on aquatic
systems and algal feedstocks (Fargione et al. 2009; Fletcher et al. 2011; Wiens et al.
2011).
1.6.5 Effect of Genetically Modified Organisms
The sustainability goals for genetically engineered algae likely would include two
other issues: (1) to minimize dissemination of genetically engineered algae (2) an
establishing method to determine whether an observed effect was caused by a
20
N. Maheshwari et al.