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Table 2 ANOVA for the five carbon pools of the Chilimo dry afromontane forest along the altitude, slope, and forest patch

From: Temporal variation of ecosystem carbon pools along altitudinal gradient and slope: the case of Chilimo dry afromontane natural forest, Central Highlands of Ethiopia

Parameters Factor DF Sum square Mean square F value Pr > F
Aboveground biomass
 ACD (t C ha−1) Forest patch 2 10,257 10,128 1.97 0.1480
Altitude class 2 33,432 16,716 3.25 0.0454*
Slope class 2 97,753 48,877 9.51 0.0025***
Time 1 930 930 0.18 0.67211
Residuals 62 318,701 5140   
Belowground biomass
 BCD (t C ha−1) Forest patch 2 1477 739 1.97 0.1480
Altitude class 2 2438 1219 3.25 0.0454*
Slope class 2 7126 3563 9.51 0.0025***
Time 1 68 58 0.18 0.6721
Residuals 62 23,233 375   
Stump biomass
StCD (N ha−1) Forest patch 2 8.31 4.16 2.83 0.0475
Altitude class 2 6.13 3.06 2.09 0.1337
Slope class 2 9.97 4.97 3.39 0.0405*
Period 1 0.45 0.45 0.30 0.5834
Residuals 57 83.77 1.47   
Deadwood biomass
 DWCD (C t ha−1) Forest patch 2 11.88 5.94 6.88 0.00401**
Altitude class 2 0.97 0.49 0.56 0.57642
Slope class 2 0.26 0.13 0.15 0.86325
Time 1 3.26 3.26 3.77 0.06314
Residuals 26 22.46 0.86   
Herbaceous biomass
 HbCD (C t ha−1) Forest patch 2 3.31 1.66 2.07 0.0146
Altitude class 2 3.59 1.80 2.25 0.1250
Slope class 2 2.50 1.25 1.57 0.2270
Residuals 27 21.58 0.80   
Humus and litter biomass
 HUCD (t C ha−1) Forest patch 2 765 382.4 4.007 0.02555*
Altitude class 2 321 160.3 1.680 0.19870
Slope class 2 607 303.3 3.178 0.055187
Period 1 804 804.0 8.423 0.00588**
Residuals 42 4009 95.4   
Soil organic carbon
 SOCD (t C ha−1) Forest patch 2 76,044 38,022 13.992 1.67e−06***
Altitude class 2 230,462 115,231 42.403 < 2e−16***
Land-use type 3 330,301 110,100 40.515 < 2e−16***
Slope class 2 11,857 5928 2.182 0.115
Depth 3 860,002 286,007 105.489 < 2e−16***
Time 1 538 538 0.198 0.657
Residuals 266 722,855 2717   
Total ecosystem carbon
 TECD (t C ha−1) NF Forest patch 2 3867 1934 0.08 0.9255
Altitude class 2 133,008 66,504 2.67 0.0775
Slope class 2 588,092 294,046 11.79 4.59e−05***
Time 1 1455 1455 0.06 0.8099
Residuals 62 1,546,631 24,946   
  1. Where: ACD Above ground carbon density, DF Degree of freedom, HbCD Herbaceous carbon density, StCD Stump carbon density, DWCD Dead wood carbon density, NF Natural forest, HUCD Humus carbon density, SOCD Soil organic carbon density, tCha-1 tone carbon per hectare, and TECD Total ecosystem carbon density