Chapter 12 Limnology Holaway
This chapter discusses the intricacies of natural redox reactions and
environments. In the beginning of the chapter, the author discusses how
chemicals naturally occur in the environment in relation to weathering. I was
shocked to learn that an increase in runoff is inversely related with the
amount of dissolved matter. I will say I do not understand redox. According to
the book redox is, “The relative availability of electrons for chemical
reactions.” The section of the chapter that I felt explained it best was the
discussion if the conversion of Fe and its states. In Fe+2(reduced) iron is easily
soluble and Fe 3+ is not. Fe is abundant where there is a low redox potential
(there is no O2 that can accept the electrons) because the O2 converts Fe2+ to
Fe 3+ which falls into the lower stratified layers with less oxygen. (making the
concentration higher) Nitrification is similar to this. However, it requires
organisms. Organisms lower the activation energy necessary for ammonium
(that is stable in water with O) so that it can oxidize it into nitrate, which is
then used for energy by those organisms.
Oxygen is critical for the oxidation reduction potential, it acts as the
receptor for electrons, raising the potential with saturation. A decrease in
temperature, an rise in atmospheric pressure (altitude), and increases with
pressure of depth causes O2 saturation to rise. Salinity can cause O2
saturation to be lowered. Respiration typically causes O2 levels to be lowered
as it is consumed to make use of ATP. Photosynthesis (the opposite equation
of respiration) can be measured by NPP or GPP. NPP can be calculated to see
if respiration is greater or lower than photosynthesis. It is also important to
note photosynthesis-irradiance and its components of compensation point
and photoinhibition and how these vary between different adaptations of
plants.
This chapter discusses the intricacies of natural redox reactions and
environments. In the beginning of the chapter, the author discusses how
chemicals naturally occur in the environment in relation to weathering. I was
shocked to learn that an increase in runoff is inversely related with the
amount of dissolved matter. I will say I do not understand redox. According to
the book redox is, “The relative availability of electrons for chemical
reactions.” The section of the chapter that I felt explained it best was the
discussion if the conversion of Fe and its states. In Fe+2(reduced) iron is easily
soluble and Fe 3+ is not. Fe is abundant where there is a low redox potential
(there is no O2 that can accept the electrons) because the O2 converts Fe2+ to
Fe 3+ which falls into the lower stratified layers with less oxygen. (making the
concentration higher) Nitrification is similar to this. However, it requires
organisms. Organisms lower the activation energy necessary for ammonium
(that is stable in water with O) so that it can oxidize it into nitrate, which is
then used for energy by those organisms.
Oxygen is critical for the oxidation reduction potential, it acts as the
receptor for electrons, raising the potential with saturation. A decrease in
temperature, an rise in atmospheric pressure (altitude), and increases with
pressure of depth causes O2 saturation to rise. Salinity can cause O2
saturation to be lowered. Respiration typically causes O2 levels to be lowered
as it is consumed to make use of ATP. Photosynthesis (the opposite equation
of respiration) can be measured by NPP or GPP. NPP can be calculated to see
if respiration is greater or lower than photosynthesis. It is also important to
note photosynthesis-irradiance and its components of compensation point
and photoinhibition and how these vary between different adaptations of
plants.
