Biomass

Biomass is a commonly measured vegetation attribute that refers to the weight of plant material within a given area. Other general terms, such as 'yield' or 'production', are sometimes used interchangeably with biomass. Units to express biomass should be selected so that actual plant weight is easy to visualize, such as lb/acre, kg/ha or g/m2 according to vegetation abundance and objectives of the inventory or monitoring program.

Biomass is one of the most commonly measured attributes in range inventory or monitoring programs. Biomass data may be collected on an individual species basis, as species groups, or as a total weight for the vegetation. Species composition may also be calculated as the contribution (percent by weight) that each species makes to the total biomass.

Biomass is an attribute that is time consuming and laborious to collect, but easy to interpret. Biomass is regarded as an important indicator of ecological and management processes in the vegetation.

  1. Ecological indicators - biomass is a measure of species dominance within the vegetation, since the demand for resources by each species is largely determined by plant size. Biomass also reflects the amount of energy stored in the vegetation, which can indicate the potential productivity at the site.
  2. Management indicators - biomass provides a variety of indicators for rangeland management. For example, it is a valuable tool to assess range condition, the carrying capacity of an area, or to make short-term stocking rate adjustments according to the amount of forage reserves and residual biomass.

Terminology Related to Biomass Sampling

Special Considerations for Biomass Sampling

The following critical issues should be considered when designing sampling protocols to determine biomass.

Measurement Techniques and Statistical Analysis

References and Further Reading

Bonham, C.D. 1989. Measurements for terrestrial vegetation. John Wiley Sons, New York, NY. pp 199-264.

Cook, C.W., and J. Stubbendieck. (eds). 1986. Range research: Basic problems and techniques. Society for Range Management, Denver, CO. pp 51-56.

Daubenmire, R. 1968. Plant communities: A textbook on plant synecology. Harper Row, New York, NY. pp 51-53.

Holechek, J.L., Pieper, R.D., and C.H. Herbel. 1995. Range management principles and practices. Prentice Hall, Englewood Cliffs, NJ. 2nd ed. pp 135-136.

Pieper, R.D. 1988. Rangeland vegetation productivity and biomass. In: P.T. Tueller. (ed). Vegetation science applications for rangeland analysis and management. Handbook of vegetation science, Volume 14. Kluwer Academic Publishers, Dordrecht. pp 449-467.