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The concentration of chlorophyll A is used as an index of phytoplankton biomass. In the ocean, phytoplankton all contain the chlorophyll pigment, which has a greenish color. Phytoplankton are microscopic organisms that live in watery environments and changes in the amount of phytoplankton indicate the change in productivity of the ocean.
[21] [22] [23] In this way, the concentration of chlorophyll within a leaf can be estimated. [24] Methods also exist to separate chlorophyll a and chlorophyll b. In diethyl ether, chlorophyll a has approximate absorbance maxima of 430 nm and 662 nm, while chlorophyll b has approximate maxima of 453 nm and 642 nm. [25]
28.2% (sunlight energy collected by chlorophyll) → 68% is lost in conversion of ATP and NADPH to d-glucose, leaving; 9% (collected as sugar) → 35–40% of sugar is recycled/consumed by the leaf in dark and photo-respiration, leaving; 5.4% net leaf efficiency. Many plants lose much of the remaining energy on growing roots.
Low-nutrient, low-chlorophyll (LNLC) regions are aquatic zones that are low in nutrients (such as nitrogen, phosphorus, or iron) and consequently have low rate of primary production, as indicated by low chlorophyll concentrations. These regions can be described as oligotrophic, and about 75% of the world's oceans encompass LNLC regions.
Express each concentration value as the ratio c/c 0, where c 0 is the concentration in a [hypothetical] standard state, with a numerical value of 1, by definition. [19] Express the concentrations on the mole fraction scale. Since mole fraction has no dimension, the quotient of concentrations will, by definition, be a pure number.
Typical examples include the Leaf Area Index, biomass, chlorophyll concentration in leaves, plant productivity, fractional vegetation cover, accumulated rainfall, etc. Such relations are often derived by correlating space-derived NDVI values with ground-measured values of these variables.
depending on whether the electrode is calibrated in millivolts or pH. For convenience the concentration, [H +], is used in place of activity. In a titration of strong acid with strong alkali, the analytical concentration of the hydrogen ion is obtained from the initial concentration of acid, C i and the amount of alkali added during titration.
Relationships between Trophic State Index, chlorophyll, phosphorus, Secchi depth, and trophic class (after Carlson 1996) [4] Trophic State Index Chlorophyll (μg/L) Phosphorus (μg/L) Secchi depth (m) Trophic Class < 30—40 0—2.6 0—12 > 8—4 Oligotrophic or hipotrophic 40—50 2.6—7.3 12—24 4—2 Mesotrophic 50—70 7.3—56 24—96