Appendix B. Method for estimating aboveground net primary productivity.
Additional details on nondestructive ANPP estimates. When vegetation such as tall grasses or shrubs formed a canopy over another layer of vegetation, we first recorded the dominant vegetation when viewed from above (in all 400 squares) and then pushed aside the top canopy layer and recorded the vegetation present underneath the top canopy. We then added these together and divided by 400. For example, if forbs comprised the dominant vegetation in 40 squares when viewed down onto the top of the canopy, and comprised the dominant vegetation of five additional squares under the shrub canopy, we counted forbs as comprising a total of 45/400*100 = 11.25% coverage in that plot.
TABLE B1. Regression equations between non-destructive multi-layered cover estimate and dry-weight, harvested biomass as described in the Methods section of the text.
|Shrub ( live foliage )||0.99||1.05||0.05||0.99||21.90||<0.0005||8|
|Shrub ( wood )||0.95||6.75||0.51||0.98||13.23||<0.0005||10|
|Grass ( at meadows )||0.98||1.75||0.07||0.99||25.06||<0.0005||11|
|Grass ( at shrublands )||0.94||1.20||0.11||0.98||10.67||<0.0005||8|
|All other forbs||0.91||0.69||0.06||0.96||11.12||<0.0005||13|