Exam 20: Ecosystem Energetics

According to the first law of thermodynamics,

Why are there not seven or eight levels to a trophic food chain?

In most terrestrial and many aquatic ecosystems,the ________ food chain is the dominant pathway of energy flow.

________ primary productivity is the total rate of photosynthesis or energy assimilated by plants.

In a temperate rain forest,primary productivity remains relatively constant.

The base of the detrital food chain is formed by

In endotherms,an increase in mass-specific metabolic rate lowers production efficiency.

When a chemical reaction results in the loss of energy from the system,the reaction is exothermic.

Secondary production in an ecosystem is always less than primary production.

Which ecosystem has the highest actual evapotranspiration?

The amount of accumulated organic matter found in an area at a given time is the ________ crop biomass.

________ efficiency is the ratio of production to assimilation,which measures how efficiently the consumer incorporates assimilated energy into secondary production.

Which pathway leads to the detrital food chain?

In most marine ecosystems,autochthonous inputs of organic carbon are greater than allochthonous inputs of carbon.

Which region represents the highest HANPP as a percentage of local NPP?

Net primary productivity in an ecosystem increases as mean annual temperature

Wealthy nations typically have lower rates of human appropriation of net primary productivity (HANPP)than developing nations.

NPP can be measured via satellite data because vegetation has

In the surface waters of oceans,the two most limiting nutrients for primary productivity are

Plants assimilate energy through the process of