Chapter 14 discusses the nutrient cycling of N, P, S, and other
nurturements. Most N is unavailable for photosynthesis being in the N2 form.
This makes the nitrogen cycle very important so that processes like
photosynthesis can still obtain usable nitrogen. (The most usable is
ammonium.) Organic N was an interesting discussion. As a soils student, I
typically think of organic N as urea because of fertilizer. In water systems,
fish are most likely to excrete ammonium because water is not a limiting
nutrient. I also learned that Molybdenum plays a key role in the function of
nitrogenase. Sulfur was discussed next, S2 transforms into hydrogen sulfide
in anoxic conditions, explaining why swamps can smell like rotten eggs.
Sulfate can keep the redox reaction high and prevent the production of
methane. Sulfur is typically not a limiting nutrient. However, phosphorus is.
Because of its naturally low amount, organisms have evolved their usage of
K to be very efficient. They are better than humans are at removing K from
wastewater. It also cannot act as an electron accepter; this is why it has a
larger impact on the environment. It is the simplest of all the nutrient cycle
graphs because K only has one abundant, inorganic form: phosphate. I also
learned how Si and Fe are critical to the other nutrient cycles, mostly as
chelators or other precipitation concerns.
nurturements. Most N is unavailable for photosynthesis being in the N2 form.
This makes the nitrogen cycle very important so that processes like
photosynthesis can still obtain usable nitrogen. (The most usable is
ammonium.) Organic N was an interesting discussion. As a soils student, I
typically think of organic N as urea because of fertilizer. In water systems,
fish are most likely to excrete ammonium because water is not a limiting
nutrient. I also learned that Molybdenum plays a key role in the function of
nitrogenase. Sulfur was discussed next, S2 transforms into hydrogen sulfide
in anoxic conditions, explaining why swamps can smell like rotten eggs.
Sulfate can keep the redox reaction high and prevent the production of
methane. Sulfur is typically not a limiting nutrient. However, phosphorus is.
Because of its naturally low amount, organisms have evolved their usage of
K to be very efficient. They are better than humans are at removing K from
wastewater. It also cannot act as an electron accepter; this is why it has a
larger impact on the environment. It is the simplest of all the nutrient cycle
graphs because K only has one abundant, inorganic form: phosphate. I also
learned how Si and Fe are critical to the other nutrient cycles, mostly as
chelators or other precipitation concerns.
