Exam 22: Biogeochemical Cycles

Fire results in the production of ash from vegetation and soil organic matter.This ash contains nutrients that are most often

Carbon dioxide concentrations fluctuate in predictable seasonal patterns on the surface of the planet largely as a result of

Which of the following nutrients has a cycle that does not contain an appreciable atmospheric phase?

Some nutrients are ________ from the soil and carried out of ecosystems by underground water flow to streams.

________ is the most common form of nitrogen exported from terrestrial ecosystems in stream water.

Which of the two basic types of biogeochemical cycles is most likely to have global cycle patterns?

In aquatic ecosystems,the phosphorous cycle moves through three states: particulate organic phosphorous,dissolved organic phosphates,and ________ phosphates.

The largest active carbon pool is

The source of all carbon in living organisms is

A danger of nitrogen saturation is

The nitrogen cycle is a series of chemical transformations,which makes it relatively insensitive to environmental conditions such as temperature and moisture.

What is the dominant sulfur gas emitted from freshwater wetlands?

Carbon is released into the atmosphere as carbon dioxide through the process of

Which of the following contains the most nutrients?

Although nitrogen can act as a fertilizer initially,too much nitrogen added to a forest system can cause forest decline.

The branch of chemistry dealing with the quantitative relationships of elements in combination is called ________.

The biogeochemical cycles of one ecosystem are typically independent from those of other ecosystems.

There is more carbon per unit of soil in cold polar regions than in the warm tropics.

Nitrogen can be returned to the atmosphere when certain bacteria convert it from nitrate into nitrogen gas,which is a process called ________.

Stratospheric ozone shields the planet from biologically harmful ultraviolet radiation.