How much biomass do plant communities pack per unit volume?

Area of Science:

• Ecology
• Plant Ecology
• Ecosystem Science

Background:

• Aboveground production in terrestrial plant communities is typically measured per unit surface area.
• Expressing production per unit volume offers a novel metric for comparing fundamental carbon-packing capacities.
• This approach allows for a more direct comparison of plant community structures and functions.

Purpose of the Study:

• To reanalyze published data from over 900 plant communities across nine ecosystems.
• To determine the average standing dry biomass per unit volume (biomass packing) across diverse ecosystems.
• To investigate how expressing biomass per unit volume modifies relationships between aboveground production and plant species richness.

Main Methods:

• Reanalysis of published data from more than 900 terrestrial plant communities.
• Calculation of standing dry biomass per unit volume (biomass packing).
• Comparison of biomass packing across nine different ecosystem types.

Main Results:

• Standing dry biomass per unit volume consistently averages around 1 kg/m³ across ecosystem types.
• Biomass packing rarely exceeds 5 kg/m³ in terrestrial plant communities.
• The relationship between aboveground production and plant species richness is altered when biomass is expressed per unit volume compared to per unit surface.

Conclusions:

• Biomass packing provides a consistent metric for carbon density in plant communities, averaging 1 kg/m³.
• This metric may offer insights into species coexistence mechanisms within plant communities.
• Biomass packing could serve as an indicator of resource use efficiency in terrestrial ecosystems.