167
© Springer International Publishing AG 2017
M. Kumar, P. Ralph (eds.), Systems Biology of Marine Ecosystems,
DOI 10.1007/978-3-319-62094-7_8
Chapter 8
Systems Biology and the Seagrass Paradox:
Adaptation, Acclimation, and Survival
of Marine Angiosperms in a Changing Ocean
Climate
Richard C. Zimmerman
Abstract Predicting adaptive fitness to any environment requires mechanistic
understanding of environmental influence on metabolic networks that control
energy assimilation, growth, and reproduction. Although the potential impacts of
environment on gene products are myriad, important phenotypic responses are often
regulated by a few key points in metabolic networks where externally supplied
resources or physiological reaction substrates limit reaction kinetics. Environmental
resources commonly limiting seagrass productivity, survival, and growth include
light and CO 2 availability that control carbon assimilation and sucrose formation.
Phosphate availability can also be important in oligotrophic tropical environments,
particularly in the presence of carbonate sediments. Temperature and macronutrient
oversupply (eutrophication) can act as confounding stressors, particularly in temperate environments. Photoacclimation can be regulated by electron transport pathways residing in the chloroplast stroma, but stress responses are often manifest by
the expression of generalized stress response proteins, both of which appear to be
affected by temperature and CO 2 availability. A systems approach is employed to
explore (1) the responses of seagrasses to the combined impacts of environmental
limiting factors that control fundamental physiological processes leading to wholeplant performance; (2) sediment diagenetic processes that facilitate nutrient remineralization, carbon sequestration, and toxin neutralization; (3) interactions with
other organisms induced by trophic cascades; and (4) impacts of human-induced
climate change that affect system dynamics at numerous points in the network.
Keywords Seagrass • Photosynthesis • Temperature • Light • CO 2 • Climate •
Metabolism
R.C. Zimmerman (*)
Department of Ocean, Earth and Atmospheric Sciences, Old Dominion University,
Norfolk, VA 23529, USA
e-mail: rzimmerm@odu.edu
© Springer International Publishing AG 2017
M. Kumar, P. Ralph (eds.), Systems Biology of Marine Ecosystems,
DOI 10.1007/978-3-319-62094-7_8
Chapter 8
Systems Biology and the Seagrass Paradox:
Adaptation, Acclimation, and Survival
of Marine Angiosperms in a Changing Ocean
Climate
Richard C. Zimmerman
Abstract Predicting adaptive fitness to any environment requires mechanistic
understanding of environmental influence on metabolic networks that control
energy assimilation, growth, and reproduction. Although the potential impacts of
environment on gene products are myriad, important phenotypic responses are often
regulated by a few key points in metabolic networks where externally supplied
resources or physiological reaction substrates limit reaction kinetics. Environmental
resources commonly limiting seagrass productivity, survival, and growth include
light and CO 2 availability that control carbon assimilation and sucrose formation.
Phosphate availability can also be important in oligotrophic tropical environments,
particularly in the presence of carbonate sediments. Temperature and macronutrient
oversupply (eutrophication) can act as confounding stressors, particularly in temperate environments. Photoacclimation can be regulated by electron transport pathways residing in the chloroplast stroma, but stress responses are often manifest by
the expression of generalized stress response proteins, both of which appear to be
affected by temperature and CO 2 availability. A systems approach is employed to
explore (1) the responses of seagrasses to the combined impacts of environmental
limiting factors that control fundamental physiological processes leading to wholeplant performance; (2) sediment diagenetic processes that facilitate nutrient remineralization, carbon sequestration, and toxin neutralization; (3) interactions with
other organisms induced by trophic cascades; and (4) impacts of human-induced
climate change that affect system dynamics at numerous points in the network.
Keywords Seagrass • Photosynthesis • Temperature • Light • CO 2 • Climate •
Metabolism
R.C. Zimmerman (*)
Department of Ocean, Earth and Atmospheric Sciences, Old Dominion University,
Norfolk, VA 23529, USA
e-mail: rzimmerm@odu.edu