Chlorophyll in the Oceans

Flashcards on Chlorophyll in the oceans.

Primary Production

The production of biomass by primary producers (bacteria, algae, plants) through photosynthesis, usually measured as carbon fixed per unit area or volume and time.

Gross Primary Productivity (GPP)

The total carbon fixed by primary producers in an ecosystem through photosynthesis.

Net Primary Productivity (NPP)

Gross primary productivity (GPP) minus the energy used by the organism for respiration: NPP = GPP - respiration.

Phytoplankton Importance

Phytoplankton is the most important in terms of carbon distribution worldwide due to its widespread global coverage, despite having a lower amount of carbon fixed per area compared to other species such as Macrocystis pyrifera.

Chlorophyll Concentration and Ocean Gyres

Low chlorophyll concentrations often correspond to ocean gyres, which are oligotrophic (low in nutrients) and have warmer waters, resulting in low net primary production.

Photosynthesis

The biological conversion of light energy into chemical bond energy stored in organic carbon compounds, occurring in chloroplasts.

Chlorophyll a

Absorbs light within the violet, blue, and red wavelengths while mainly reflecting green, giving chlorophyll its green appearance.

Accessory Photosynthetic Pigments

Broaden the spectrum of light absorbed, increasing the range of wavelengths usable in photosynthesis.

Light Attenuation

Reduction of light intensity and quality as it passes through water, influenced by factors like water clarity, suspended particles, and depth.

Irradiance

A measure of how much light energy is hitting a surface (e.g., the ocean surface) in a certain amount of time.

Photoinhibition

Strategies plants use to protect their organelles from too much light, such as using different accessory pigments.

Fluorescence

The re-emission of light by chlorophyll molecules after absorbing light, which can be measured to assess chlorophyll concentration.

Fluorometer

A device used to measure fluorescence.

Satellite Imagery

Used to observe broad changes in oceans, such as climate change impacts on chlorophyll distribution; key systems include SeaWIFS and MODIS.

Warm vs. Cold Water

Warm water typically has lower primary production, while colder water has higher primary production (often near the poles).

Toxic Algae Blooms

Can be detected by satellites; an example is the cyanobacteria Nodularia spumigena in the Baltic Sea, which produces biotoxins.

Key Limiting Factor in Marine Photosynthesis

Light

Chlorophyll Measurement Importance

Essential for understanding how carbon moves around the marine system and how it functions.