Below-Ground Net Primary Production (BNPP): Root Ingrowth Donuts

Core Areas: 

Five Points Creosote

Five Points Creosote
Photo taken August 2008.

Deep Well

Deep Well
Looking east from Deep Well Met Station.  Photo taken May 1, 2002.

Root Donuts

Root Donuts
Joe Fargione filling in the root donut after collecting the sample. Photo taken December 1, 2005.

Root Donuts

Root Donuts
Joe Fargione filling in the root donut after collecting the sample. Photo taken December 1, 2005.

Root Donuts

Root Donuts
Joe Fargione filling in the root donut after collecting the sample. Photo taken December 1, 2005.

Root Donuts

Root Donuts
Looking into a root donut after the sample has been collected and before it has been filled back up with soil.  Photo taken December 1, 2005.

Root Donuts

Root Donuts
Michell Thomey collecting root donut sample.  Photo taken December 1, 2005.

Root Donut

Root Donut
Michell Thomey collecting root donut sample.  Photo taken December 1, 2005.

Root Donuts

Root Donuts
Michell Thomey collecting root donut sample.  Photo taken Decmeber 1, 2005.

Root Donuts

Root Donuts
Root donut after it has been filled back in with soil and the cap still off.  Photo taken December 1, 2005.

Root Donuts

Root Donuts
Joe Fargione sifting soil to fill in the root donuts.  Photo taken December 1, 2005.

Root Donuts

Root Donuts
Joe Fargione sifting soil to fill in the root donuts.  Photo taken December 1, 2005.

In 2005, root ingrowth donuts were established on the Sevilleta NWR to monitor below ground biomass under different conditions and to compare estimates of root production between root ingrowth donut and mini-rhizonton tube methods at four sites on the east side of the refuge. Soil and roots are collected from the "donuts" annually in late fall after the growing season, and structures are then re-established in situ for consecutive harvests for the following years. Each structure allows roots to be harvested at two depths (0-15 and 15-30cm) to estimate root production, or "below ground net primary productivity".

They were co-located with previously established mini-rhizotron tubes with ten replicate structues in both burned (2003) and unburned mixed blue and black grama dominated grassland plots (10 burned, 10 unburned) near Deep Well, 20 replicates on nitrogen fertilization plots (10 fertilized, 10 control), and 10 replicates in a creosote dominated shrubland located at the Five Points Creosote Core site.