Treatment descriptions for stone-soil systems in 2006 planted dry down and field-testing in Ithaca, NY, U.S. Density and free drainage moisture were tested in both compaction testing and the plant dry down study at the aggregate treatment level in oneway ANOVA at a = 0.05 and were significant P < 0.001. Soil alone was not tested, but shown for illustration in compaction testing.
Isolated component testing | |||
Aggregate | Gravel | Stalite | |
Aggregate Gs | 2.66 | 1.44 (from supplier) | |
Compacted aggregate (Mg m−3) | 1.75 | 0.92 | |
Compacted porosity (m3/m3) | 34% | 36% | |
Soil Gs | 2.67 | 2.67 | |
Compaction testing: | Gravel-base | Stalite-base | Soil |
n = 5 | System | System | Alone |
Compacted density (Mg m−3) | 1.97±0.005 | 1.16±0.005 | 1.76±0.005 |
Replicate volume (m3) | 0.00262 | 0.00262 | 0.00262 |
Total compacted porosity (m3/m3) | 26% | 27% | 34% |
Free Drain Moisture (m3/m3) | 17.9%±0.85 | 19.7%±0.70 | 33.26±0.05 |
Observed gravitational porosity | 8% | 7.3% | 0.74% |
Free drain as % of total porosity | 30.9% | 27% | 2.2% |
Plant dry down study | Gravel-base | Stalite-base | |
n = 15 | System | System | |
Compacted density (Mg m−3) | 2.04 (±0.01) | 1.28 (±0.01) | |
Replicate volume (m3) | 0.00524 | 0.00524 | |
Gravitational drainage moisture* (m3/m3) | 0.116±0.002 | 0.158±0.003 | |
Dry endpoint moisture** (m3/m3 @ 1500 kPa matric tension) | 0.046±0.002 | 0.060±0.002 | |
Plant Available Moisture | 7.0% | 9.8% | |
Infiltration field measure | Gravel-base | Stalite-base | Soil |
n = 3 | System | System | Alone |
Field density (Mg m−3) | 1.98 | 0.80 | 1.78 |
Infiltration rate (cm hr−1) | >60 | >60 | 1.24 |
↵* Moisture content and Standard Error of mean derived from initial data measures after 9 hours free drainage.
↵**Moisture content and Standard Error of model fit values derived from predicted values (a = 0.05) in simple linear regression (Minitab 14) using negative natural log transformed matric tension and volumetric moisture data.