Soil carbon inventories under a bioenergy crop (switchgrass): Measurement limitations

被引:126
作者
Garten, CT [1 ]
Wullschleger, SD [1 ]
机构
[1] Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA
关键词
D O I
10.2134/jeq1999.00472425002800040041x
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
Approximately 5 yr after planting, coarse root (>2 mm) carbon (C) and soil organic C (SOC) inventories (0-10 cm deep) were compared under different types of plant cover at four switchgrass (Panicum virgatum L.) production field trials in the southeastern USA. There was significantly (p less than or equal to 0.05) more coarse root C under switchgrass (Alamo variety) and forest col-er than under tall fescue (Festuca arundinacea Schreb.), corn (Zea mays L,), or native pastures of mixed grasses. Inventories of SOC under switchgrass were not significantly greater than SOC inventories under other plant covers. At some locations the statistical power associated with ANOVA of SOC inventories was low, which raised questions about whether differences in SOC could be detected statistically. A minimum detectable difference (MDD) for SOC inventories was calculated. The MDD is the smallest detectable difference between treatment means once the variation, significance level, statistical power, and sample size are specified. The analysis indicated that a difference of approximate to 50 mg SOC/cm(2) or 5 Mg SOC/ ha, which is approximate to 10 to 15% of existing SOC, could be detected with reasonable sample sizes (n = 16) and good statistical power (1 - beta = 0.90). The smallest difference in SOC inventories that can be detected, and only with exceedingly large sample sizes (n > 100), is approximate to 2 to 3% (approximate to 10 mg SOC/cm(2) or 1 Mg SOC/ha), These measurement limitations have implications for monitoring and verification of proposals to ameliorate increasing global atmospheric CO2 concentrations by sequestering C in soils.
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页码:1359 / 1365
页数:7
相关论文
共 16 条
  • [1] [Anonymous], 2007, Biostatistical analysis
  • [2] BRANSBY DI, 1991, ENERGY BIOMASS WASTE, V15, P333
  • [3] Maximum rooting depth of vegetation types at the global scale
    Canadell, J
    Jackson, RB
    Ehleringer, JR
    Mooney, HA
    Sala, OE
    Schulze, ED
    [J]. OECOLOGIA, 1996, 108 (04) : 583 - 595
  • [4] CHANGES IN SOIL CARBON INVENTORIES FOLLOWING CULTIVATION OF PREVIOUSLY UNTILLED SOILS
    DAVIDSON, EA
    ACKERMAN, IL
    [J]. BIOGEOCHEMISTRY, 1993, 20 (03) : 161 - 193
  • [5] CARBON STORAGE BY INTRODUCED DEEP-ROOTED GRASSES IN THE SOUTH-AMERICAN SAVANNAS
    FISHER, MJ
    RAO, IM
    AYARZA, MA
    LASCANO, CE
    SANZ, JI
    THOMAS, RJ
    VERA, RR
    [J]. NATURE, 1994, 371 (6494) : 236 - 238
  • [6] GEBHART DL, 1994, J SOIL WATER CONSERV, V49, P488
  • [7] Kirk R.E., 2012, EXPT DESIGN PROCEDUR, P302
  • [8] ROOT DISTRIBUTION UNDER SOME FOREST TYPES NATIVE TO WEST-VIRGINIA
    KOCHENDERFER, JN
    [J]. ECOLOGY, 1973, 54 (02) : 445 - 448
  • [9] Lal R., 1998, POTENTIAL US CROPLAN
  • [10] CHANGES IN SOIL CARBON STORAGE AFTER CULTIVATION
    MANN, LK
    [J]. SOIL SCIENCE, 1986, 142 (05) : 279 - 288