Figure 6

Pore size distribution for image-based (> 18.2 μm) pores for depression (a) and slope (b) in the control cores (solid lines) and in plant grown cores (dash lines) in prairie (▼) and switchgrass (●) cropping systems. Shown are means with error bars representing standard errors (n = 3). Lower case letters indicate significant differences between topographical positions within each system for plant-grown cores (p < 0.05); upper case letters indicate significant differences between cropping systems within each topographical position for plant-grown cores (p < 0.05).