Movement of Organic Matter

What is it? Organic matter consists of the dead and decaying plants and animals in the environment. Decomposition of organic matter affects the availability of nutrients to plants and animals, as well as soil formation and soil stability.

How is it studied? Researchers ask questions about what controls the amount of organic matter in the ecosystem, and what effect the movement of organic matter has on the ecosystem?

The amount of organic matter in an ecosystem can be measured by:
-collecting and weighing leaves and other debris or “litter” that falls into containers placed on the forest floor.
-placing mesh bags of litter on the earth and noting how long it takes to decay, and
-taking samples from the soil and analyzing the organic components.
-tracing the nutrients that are released into the ecosystem as the organic matter decays

The rate at which organic matter decays and becomes available to plants and animals in the system can then be measured, and questions such as "How does the decomposition of organic material affect the soil?" can be addressed. Understanding the availability of organic nutrients in the soil will help scientists to learn how soils may be affected by changes in temperature and rainfall.

	Student scientists collect forest litter.
(this is what the litter bin looks like)

Organic Matter Research in LTER

Litter bags placed on the ground at the Sevilleta LTER site (above) and the Bonanza Creek LTER site (below) will show the effects of litter decomposition in defferent ecosystems.

Long-term Intersite Decomposition Experiment Team: LIDET

LTER and other researchers are testing the degree to which climate and soil quality and control the nutrient dynamics of decomposing leaf, wood, and fine-root litter in a 10-year-long, 28-site-wide experiment.

Researchers at the participating sites (including 17 from the LTER Network) have collected litter, placed materials in the field, and provided relevant information or baseline data about their sites so comparisons can be made.

The (LIDET study is composed of field collaborators who oversee the study at their respective sites; modelers who will predict C, N, and P dynamics and validate models from the field study; and a central analysis group which performs chemical analysis, data management, and preliminary data analysis.