Abstract
A modified root ingrowth method was developed to minimize destructive sampling in experiments with limited space, and used to estimate belowground net primary production and root tissue quality in a native semiarid grassland exposed to elevated CO2 for five years. Increases in root production of over 60% were observed with elevated CO2 during years of intermediate levels of precipitation, with smaller effects in a very wet year and no effects in a very dry year. Aboveground to belowground production ratios, and the depth distribution of root production, did not differ between ambient and elevated CO2 treatments. Root soluble concentrations increased an average of 11% and lignin concentrations decreased an average of 6% with elevated CO2, while nitrogen concentrations decreased an average of 21%. However, most tissue quality responses to CO2 varied greatly among years, and C:N ratios were higher in only one year (22 ambient vs. 33 elevated). Among years, root nitrogen concentrations declined with increasing aboveground plant nitrogen yield, and increased over the study period. Estimates of root production by the ingrowth donut method were much lower than previous estimates in the shortgrass steppe based on 14C decay. We discuss reasons why all ingrowth methods will always result in relative rather than absolute estimates of root production.
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Abbreviations
- NDF:
-
neutral detergent fiber
- ADF:
-
acid detergent fiber
References
G I Agren T Ingestad (1987) ArticleTitleRoot:shoot ratio as a balance between nitrogen productivity and photosynthesis Plant Cell Environ 10 579–586
J A Arnone SuffixIII J G Zaller E M Spehn P A Niklaus C E Wells C Körner (2000) ArticleTitleDynamics of root systems in native grasslands: Effects of elevated atmospheric CO2 New Phytol 147 73–85 Occurrence Handle1:CAS:528:DC%2BD3cXms1ylt7g%3D
I C Burke W K Lauenroth D G Milchunas (1996) Biogeochemistry of managed grasslands in the Central Grasslands of North America E A Paul K Paustian E T Elliott C V Cole (Eds) Soil Organic Matter in Temperate Agroecosystems: Long-term Experiments in North America Lewis Publ Chelsea, MI 85–102
D C Coleman (1976) A review of root production processes and their influence on soil biota in terrestrial ecosystems J M Anderson A Macfadyen (Eds) The Role of Terrestrial and Aquatic Organisms in Decomposition Processes Blackwell Scientific Publications Oxford, England 417–434
P S Curtis E G O’Neill J A Teeri D R Zak K S Pregitzer (1994) ArticleTitleBelowground responses to rising atmospheric CO2: Implications for plants, soil biota and ecosystem processes Plant Soil 165 1–6 Occurrence Handle1:CAS:528:DyaK2MXjtFGhtro%3D
B G Drake M A González-Meler S P Long (1997) ArticleTitleMore efficient plants: A consequence of rising atmospheric CO2? Ann. Rev. Plant Physiol. Mol. Biol 48 609–639 Occurrence Handle1:CAS:528:DyaK2sXjs1eltbY%3D
J A Entry C B Backman (1995) ArticleTitleInfluence of carbon and nitrogen on cellulose and lignin degradation in forest soils Can. J. For. Res 25 1231–1236 Occurrence Handle1:CAS:528:DyaK2MXosl2ksb0%3D
A H Fitter J D Graves J Wolfenden G K Self T K Brown D Bogie T A Mansfield (1997) ArticleTitleRoot production and turnover and carbon budgets of two contrasting grasslands under ambient and elevated atmospheric carbon dioxide concentrations New Phytol 137 247–255
H W Hunt E T Elliot J K Detling J A Morgan D X Chen (1996) ArticleTitleResponses of a C3 and C4 perennial grass to elevated CO2 and climate change Global Change Biol 2 35–47
R B Jachson H L Reynolds (1996) ArticleTitleNitrogen and ammonium uptake for single- and mixed-species communities grown at elevated CO2 Oecologia 105 74–80
J D Joslin M H Wolfe P J Hanson (2000) ArticleTitleEffects of altered water regimes on forest root systems New Phytol 147 117–129
J Y King A R Mosier J A Morgan D R LeCain D G Milchunas W J Parton (2004) ArticleTitleChanges in aboveground plant nitrogen in shortgrass steppe following growth under elevated atmospheric CO2 Ecosystems 7 147–160 Occurrence Handle1:CAS:528:DC%2BD2cXjslyksbo%3D
W K Lauenroth D G Milchunas (1991) The shortgrass steppe R T Coupland (Eds) Natural Grasslands, Introduction and Western Hemisphere Ecosystems of the World 8A, Elsevier Amsterdam 183–226
W K Lauenroth W C Whitman (1971) ArticleTitleA rapid method for washing roots J. Range Manage 24 308–309
Lee C A 1990 The spatial distribution of roots for three plant lifeforms in the shortgrass steppe. Thesis, Colorado State University, Fort Collins, Colorado. 114 p
J W Leetham D G Milchunas (1985) ArticleTitleThe composition and distribution of soil microarthropods in the shortgrass steppe in relation to the soil water, root biomass, and grazing by cattle Pedobiologia 28 311–325
S A Levin H A Mooney C Field (1989) ArticleTitleThe dependence of plant root:shoot ratios on internal nitrogen concentration Ann. Bot 64 71–75
P Loiseau J F Soussana (1999) ArticleTitleElevated CO2, temperature increase and N supply effects on the turnover of belowground carbon in a temperate grassland ecosystem Plant Soil 210 233–247 Occurrence Handle1:CAS:528:DyaK1MXnt1KrsLw%3D
D G Milchunas W K Lauenroth (1989) ArticleTitleThree-dimensional distribution of plant biomass in relation to grazing and topography in the shortgrass steppe Oikos 55 82–86
D G Milchunas W K Lauenroth (1992) ArticleTitleCarbon dynamics and estimates of primary production by harvest, C14 dilution, and C14 turnover Ecology 73 593–607
D G Milchunas W K Lauenroth (2001) ArticleTitleBelowground primary production by carbon isotope decay and long-term root biomass dynamics Ecosystems 4 139–150 Occurrence Handle1:CAS:528:DC%2BD3MXjvVynurY%3D
D G Milchunas W K Lauenroth (1995) ArticleTitleInertia in plant community structure: state changes after cessation of nutrient enrichment stress Ecol Applic 5 452–458
D G Milchunas W K Lauenroth P Chapman M K Land Kazempour (1989) ArticleTitlePlant communities in relation to grazing, topography, and precipitation in a semiarid grassland Vegetatio 80 11–23
Milchunas D G, Mosier A R, Morgan J A, LeCain D, King J Y, Nelson J A 2004 CO2 and grazing effects on a shortgrass steppe: forage quality versus quantity for ruminants. Oikos (submitted)
D G Milchunas O E Sala W K Lauenroth (1988) ArticleTitleA generalized model of the effects of grazing by large herbivores on grassland community structure Am. Nat 132 87–106
J A Morgan D R LeCain A R Mosier D G Milchunas (2001) ArticleTitleElevated CO2 enhances water relations and productivity and affects gas exchange in C3 and C4 grasses of the Colorado shortgrass steppe Global Change Biol 7 451–466
J A Morgan A R Mosier D G Milchunas D R LeCain J A Nelson W J Parton (2004) ArticleTitleCO2 enhances productivity but alters species composition and reduces forage quality in the Colorado shortgrass steppe Ecol. Applic 14 208–219
E Naumburg D C Housman T E Huxman T N Charlet M E Loik S D Smith (2003) ArticleTitlePhotosynthetic responses of Mojave Desert shrubs to free air CO2 enrichment are greatest during wet years Global Change Biol 9 276–285
J A Nelson J A Morgan D R LeCain A R Mosier D G Milchunas W J Parton (2004) ArticleTitleElevated CO2 increases soil moisture and enhances plant water relations in a long-term field study in semi-arid shortgrass steppe of Colorado Plant Soil 259 169–179 Occurrence Handle1:CAS:528:DC%2BD2cXisVWlt7Y%3D
R J Norby (1994) ArticleTitleIssues and perspectives for investigating root responses to elevated atmospheric carbon dioxide Plant Soil 165 9–20 Occurrence Handle1:CAS:528:DyaK2MXjtFGhtrs%3D
R J Norby R B Jackson (2000) ArticleTitleRoot dynamics and global change: seeking an ecosystem perspective New Phytol 147 3–12 Occurrence Handle1:CAS:528:DC%2BD3cXms1ylt7w%3D
C E Owensby P I Coyne J H Ham L M Auen A K Knapp (1993) ArticleTitleBiomass production in a tallgrass prairie ecosystem exposed to ambient and elevated CO2 Ecol. Applic 3 644–653
C E Owensby P I Coyne L M Auen (1993) ArticleTitleNitrogen and phosphorus dynamics of a tallgrass prairie ecosystem exposed to elevated carbon dioxide Plant Cell Environ 16 843–850 Occurrence Handle1:CAS:528:DyaK2cXhs1aks70%3D
L Pages A G Bengough (1997) ArticleTitleModeling minirhizotron observations to test experimental procedures Plant Soil 189 81–89 Occurrence Handle1:CAS:528:DyaK2sXktVKhs70%3D
E Pendall S Del Grosso J Y King D R LeCain D G Milchunas J A Morgan A R Mosier D S Ojima W A Parton P P Tans J W C White (2003) ArticleTitleElevated atmospheric CO2 effects and soil water feedbacks on soil respiration components in a Colorado grassland Global Biogeochem. Cycl 17 15–1–15–13
K S Pregitzer D R Zak J Maziasz J DeForest P S Curtis J Lussenhop (2000) ArticleTitleFine root growth, mortality, and morphology in a factorial elevated atmospheric CO2 × soil N avaiability experiment Ecol. Applic 10 18–33
H H Rogers G B Runion S V Krupa (1994) ArticleTitlePlant responses to atmospheric CO2 enrichment with emphasis on roots and the rhizosphere Environ. Pollut 83 155–189 Occurrence Handle1:STN:280:DC%2BD2c7psFOlsw%3D%3D Occurrence Handle15091762
N A Scott D Binkley (1997) ArticleTitleFoliage litter quality and annual net N mineralization: Comparison across North American forest sites Oecologia 111 151–159
P L Sims J S Singh (1978) ArticleTitleThe structure and function of ten western North American grasslands. III. Net primary production, turnover, and efficiencies of energy capture and water use J. Ecol 66 573–597
R H Skinner J A Morgan J D Hanson (1999) ArticleTitleCarbon and nitrogen reserve remobilization following defoliation: Nitrogen and elevated CO2 effects Crop Sci 39 1749–1756
J Swinnen J A VanVeen R Merckx (1994) ArticleTitleLosses of C-14 from roots of pulse-labeled wheat and barley during washing from soil. Plant Soil 166 93–99 Occurrence Handle1:CAS:528:DyaK2MXjsFKmu7s%3D
J Thorp (1948) How soils develop under grass A Stefferud (Eds) Grass: The Yearbook of Agriculture U.S. Dept. Agric Washington, DC 55–66
M Van Noordwijk P Martikainen P Bottner E Cuevas C Rouland S S Dhillion (1998) ArticleTitleGlobal change and root function Global Change Biol 4 759–772
P J Van Soest (1963) ArticleTitleUse of detergents in the analysis of fibrous feeds. II. A rapid method for the determination of fiber and lignin J. Assoc Official Agr. Chem 46 829–835 Occurrence Handle1:CAS:528:DyaF2cXnvVGjtQ%3D%3D
P J Van Soest (1967) ArticleTitleDevelopment of a comprehensive system of feed analysis and its application to forages J. Anim. Sci 26 119–128
Van Soest P J 1975 Physio-chemical aspects of fiber digestion. In:Digestion and Metabolism in the Ruminant. Eds. I W McDonald and A C I Warner. pp. 352–365. Proc. IV Int. Symp. on Ruminant Physiology, Sydney, Aust. 602 p
JE Weaver (1958) ArticleTitleSummary and interpretation of underground development in natural grassland communities Ecol. Monogr 28 55–78
S D Wullschleger T J Tschaplinski R J Norby (2002) ArticleTitlePlant water relations at elevated CO2 – Implications for water-limited environments Plant Cell Environ 25 319–331 Occurrence Handle10.1046/j.1365-3040.2002.00796.x Occurrence Handle11841673
D R Zak K S Pregitzer J S King W E Holmes (2000) ArticleTitleElevated atmospheric CO2, fine roots and the response of soil microorganisms: a review and hypothesis New Phytol 147 201–222 Occurrence Handle1:CAS:528:DC%2BD3cXms1yltLs%3D
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Milchunas, D.G., Mosier, A.R., Morgan, J.A. et al. Root production and tissue quality in a shortgrass steppe exposed to elevated CO2: Using a new ingrowth method. Plant Soil 268, 111–122 (2005). https://doi.org/10.1007/s11104-004-0230-7
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DOI: https://doi.org/10.1007/s11104-004-0230-7