Exam 21: Decomposition and Nutrient Cycling

Bacteria and fungi secrete ________ into plant and animal tissues to break down the complex organic compounds.

In general,litter with a C/N ratio greater than 30 leads to immobilization,litter with a C/N ratio less than 20 leads to mineralization,and litter with a C/N ratio of 20-30 leads to a balance of immobilization and mineralization resulting in no net N production.If garlic mustard leaf litter collected on the forest floor had 43.2 percent C and 1.16 percent N,this tissue would lead to

Aerobic decomposition occurs at a faster rate than anaerobic decomposition.

The uptake of minerals by decomposers is referred to as

Decomposition proceeds faster in moist environments than in dry environments.

The microbial loop results from

The rate of nutrient cycling in an ecosystem is a function of physical characteristics of the ecosystem,not biological processes such as photosynthesis and decomposition.

The process of decomposition releases ________ to bacteria and fungi.

Litterbags can be used to estimate the rate of decomposition.

The rate of decomposition is greatest in

Which of the following is true regarding POM?

In open-water systems such as lakes and oceans,decomposition occurs mostly in the surface layer.

When calculating leaf litter decomposition,what must be taken into account?

In decomposition,fungi generally

Soil organic matter contains recalcitrant compounds that are of low quality and contain little energy for decomposers.

In a process known as the ________,the rise and fall of water depth with tidal cycles bring nutrients into coastal marshes from coastal ocean waters.

How can minerals captured via immobilization be released back into the soil?

Coastal zones of contact between freshwater from streams and rivers and saltwater from the ocean are called

The rate of decomposition is faster for proteins,simple sugars,cellulose,and hemicellulose than it is for lignin.

The incorporation of mineral nutrients into an organic form is called ________.