semivariograms of total soil N, N-mineralization potential, and total plant N measured in grazed and
ungrazed grassland at three sites in Yellowstone National Park. For all sites, we report results for random,
linear, and spherical models. In addition, if a higher order polynomial model resulted in a statistically
siginificant model fit both for the overall test of model significance (P < 0.05) and for each of the
parameter coefficients included in the model (P < 0.05 for each coefficient), then results are presented
for this model. RMSE for the selected model at each site is shown in bold.
|
Total Soil Nitrogen |
N-mineralization Potential |
||||||||
|
% |
mg/g dry soil/10 days |
||||||||
|
Site |
Treatment |
Model |
RMSE |
df |
P > F |
RMSE |
df |
P > F |
|
|
4 x 4 m grids: |
|||||||||
|
Lamar |
Ungrazed |
Mean Fit (random) |
0.0370 |
10 |
0.0270 |
10 |
|||
|
Linear |
0.0143 |
9 |
0.003 |
0.0238 |
9 |
0.162 |
|||
|
Spherical |
0.0057 |
8 |
0.0129 |
8 |
|||||
|
4th order Polynomial |
0.0087 |
6 |
0.025 |
||||||
|
Lamar |
Grazed |
Mean Fit (random) |
0.0402 |
10 |
0.0431 |
10 |
|||
|
Linear |
0.0285 |
9 |
0.051 |
0.0394 |
9 |
0.198 |
|||
|
Spherical |
0.0474 |
8 |
0.0529 |
8 |
|||||
|
3rd Order Polynomial |
0.0111 |
7 |
0.007 |
0.0059 |
7 |
0.006 |
|||
|
Blacktail |
Ungrazed |
Mean Fit (random) |
0.0834 |
10 |
0.0185 |
10 |
|||
|
Linear |
0.0491 |
9 |
0.020 |
0.0167 |
9 |
0.183 |
|||
|
Spherical |
0.0609 |
8 |
0.0193 |
8 |
|||||
|
4th order Polynomial |
0.0237 |
6 |
0.017 |
0.0030 |
6 |
0.003 |
|||
|
Blacktail |
Grazed |
Mean Fit (random) |
0.0127 |
10 |
0.0462 |
10 |
|||
|
Linear |
0.0141 |
9 |
0.995 |
0.0312 |
9 |
0.039 |
|||
|
Spherical |
0.0125 |
8 |
0.0578 |
8 |
|||||
|
2nd Order Polynomial |
0.0057 |
8 |
0.017 |
||||||
|
Stevens Creek |
Ungrazed |
Mean Fit (random) |
0.0323 |
10 |
0.1054 |
10 |
|||
|
Linear |
0.0298 |
9 |
0.208 |
0.1153 |
9 |
0.718 |
|||
|
Spherical |
0.0254 |
8 |
0.1110 |
8 |
|||||
|
4th order Polynomial |
0.0083 |
6 |
0.013 |
0.0245 |
7 |
0.019 |
|||
|
Grazed |
Mean Fit (random) |
0.0315 |
10 |
0.0176 |
10 |
||||
|
Linear |
0.0151 |
9 |
0.007 |
0.0032 |
9 |
0.0001 |
|||
|
Spherical |
0.0180 |
8 |
0.0210 |
8 |
|||||
|
4th order Polynomial |
0.0122 |
6 |
0.042 |
||||||
|
Blacktail: 60 X 30 m grid |
|||||||||
|
Ungrazed |
Mean Fit (random) |
0.0598 |
5 |
0.1405 |
5 |
||||
|
Linear |
0.0578 |
4 |
0.309 |
0.1453 |
4 |
0.458 |
|||
|
Spherical |
0.0737 |
3 |
0.0272 |
3 |
0.003 |
||||
|
Grazed |
Mean Fit (random) |
0.1108 |
5 |
0.1070 |
5 |
||||
|
Linear |
0.0294 |
4 |
0.001 |
0.0354 |
4 |
0.003 |
|||
|
Spherical |
0.1259 |
3 |
0.0450 |
3 |
|||||
|
Exponential |
0.0185 |
3 |
|||||||
|
Extractable Mineral |
Total Plant Nitrogen |
||||||||
|
Nitrogen (mg/g dry soil/10 days) |
g/m2 |
||||||||
|
Site |
Treatment |
Model |
RMSE |
df |
P > F |
RMSE |
df |
P > F |
|
|
4 x 4 m grids: |
|||||||||
|
Lamar |
Ungrazed |
Mean Fit |
0.1337 |
10 |
0.14657 |
10 |
|||
|
Linear |
0.1560 |
9 |
0.677 |
0.1467 |
9 |
0.350 |
|||
|
Spherical |
0.1471 |
8 |
0.13647 |
8 |
|||||
|
Lamar |
Grazed |
Mean Fit (random) |
0.2372 |
10 |
0.91557 |
10 |
|||
|
Linear |
0.2147 |
9 |
0.113 |
0.86027 |
9 |
0.160 |
|||
|
Spherical |
0.2569 |
8 |
0.81655 |
8 |
|||||
|
Blacktail |
Ungrazed |
Mean Fit (random) |
0.1572 |
10 |
0.202 |
10 |
|||
|
Linear |
0.3830 |
9 |
0.381 |
0.12036 |
9 |
||||
|
Spherical |
0.3694 |
8 |
0 |
8 |
|||||
|
2nd Order Polynomial |
0.05164 |
8 |
<0.0001 |
||||||
|
3rd Order Polynomial |
0.0605 |
0.000 |
|||||||
|
Blacktail |
Grazed |
Mean Fit (random) |
1.5245 |
10 |
0.24191 |
10 |
|||
|
Linear |
1.3988 |
9 |
0.123 |
0.21414 |
9 |
0.084 |
|||
|
Spherical |
1.2835 |
8 |
|||||||
|
4th order Polynomial |
0.15598 |
6 |
0.050 |
||||||
|
Stevens Creek |
Ungrazed |
Mean Fit (random) |
0.0804 |
10 |
0.6074 |
10 |
|||
|
Linear |
0.3386 |
9 |
0.164 |
0.49005 |
9 |
0.033 |
|||
|
Spherical |
0.2977 |
8 |
|||||||
|
Grazed |
Mean Fit (random) |
0.1956 |
10 |
0.13482 |
10 |
||||
|
Linear |
0.1243 |
9 |
0.163 |
0.09606 |
9 |
0.010 |
|||
|
Spherical |
0.1146 |
8 |
|||||||