Primary Productivity

Vocabulary flashcards covering primary productivity concepts, GPP and NPP equations, ecological efficiency statistics, and factors affecting ecosystem productivity.

Primary Productivity

The rate of photosynthesis of all producers in an area over a given period of time.

Units of Primary Productivity

$\text{Kcal/m}^2\text{/yr}$ (representing energy per area per time).

Respiration Loss (RL)

The energy that plants use up from what they generate via photosynthesis by doing cell respiration.

Gross Primary Productivity (GPP)

The total amount of sun energy that plants capture and convert to glucose through photosynthesis.

Net Primary Productivity (NPP)

The amount of energy leftover for consumers after plants have used some for respiration.

Net Primary Productivity Formula

$$\text{NPP} = \text{GPP} - \text{RL}$$

Gross Primary Productivity Formula

$$\text{GPP} = \text{NPP} + \text{RL}$$

Ecological Efficiency

The portion of incoming solar energy that is captured by plants and converted into biomass (NPP or food available for consumers).

Solar Energy Conversion to GPP

Generally, only $1\%$ of all incoming sunlight is converted into GPP via photosynthesis.

GPP Conversion to Biomass (NPP)

Of the $1\%$ of sunlight converted into GPP, only about $40\%$ is converted into biomass or plant growth (NPP).

Factors Increasing NPP

Water availability, higher temperature, and nutrient availability.