Stabilization of new carbon inputs rather than old carbon decomposition determines soil organic carbon shifts following woody or herbaceous vegetation transitions
- 769 Downloads
Background and aims
Although numerous studies have quantified the effects of land-use changes on soil organic carbon (SOC) stocks, few have examined simultaneously the weight of carbon (C) inputs vs. outputs in shaping these changes. We quantified the relative importance of soil C inputs and outputs in determining SOC changes following the conversion of natural ecosystems to pastures or tree plantations, and evaluated them in light of variations in biomass production, its quality (C:N) and above/belowground allocation patterns.
We sampled soils up to one-meter depth under native grasslands or forests and compared them to adjacent sites with pastures or plantations to estimate the proportion of new SOC (SOCnew) retained in the soil and the decomposition rates of old SOC (k SOC-old ) based on δ 13C shifts. We also analyzed these changes in the particulate organic matter fraction (POM) and estimated above and belowground net primary production (ANPP and BNPP) from satellite images, as well as changes in vegetation and soil’s C:N ratios.
The conversion of grasslands to tree plantations decreased total SOC contents while the conversion of forests to pastures increased SOC contents in the topsoil but decreased them in deep layers, maintaining similar soil stocks up to 1 m. Changes in POM were less important and occurred only in the topsoil after cultivating pastures, following SOC changes. Surprisingly, both land-use trajectories showed similar decomposition rates in the topsoil and therefore overall SOC changes were not correlated with C outputs (k SOC-old ) but were significantly correlated with C inputs and their stabilization as SOCnew (similar results were obtained for the POM fraction). Pastures although decreased ANPP (as compared to forest) they increased belowground allocation and C:N ratios of their inputs to the soil, probably favoring the retention and stabilization of their new C inputs. In contrast, tree plantations increased ANPP but decreased BNPP (as compared to grasslands) and scarcely accumulated SOCnew probably as a result of the high C retention in standing biomass.
Our results suggest that SOC changes are mainly controlled by the quantity and quality of C inputs and their retention in the soil, rather than by C outputs in these perennial subtropical ecosystems.
KeywordsSoil organic carbon Decomposition rate Roots Lands use change
We would like to thank Luís Colconvet, Martín Pinazzo, Norberto Pahr, Santiago Lacorte, Hernan Dieguez, CamiloBagnato, Daniel Castillo, Lucía Romero, Alberto Sosa, Hugo Reis (PINDO S.A.), Ricardo Vilm, Carlos Navajas, Horacio Beltramino, HampelHorman and Carlos Vera (DANZER S.A.) for allowing and collaborating in our field work. We thank to Pablo Baldassini for their support in image processing. This research was partially funded by FONCYT (PICT 2199 and PICT 06-1764), UBACYT (0835 and 20020090200128), CONICET (PIP 555) and by a grant from the Inter-American Institute for Global Change Research (IAI, CRN 3095), which is supported by the US National Science Foundation (Grant GEO-1128040). Roxana Paola Eclesia was supported by a master degree scholarship from INTA.
- Amundson R, Baisden W (2001) Stable isotope tracers and mathematical models in soil organic matter studies. In: Sala OE, Jackson RB, Mooney HA, Howarth RW (eds) Methods in ecosystem science. Springer-Verlag, New York, pp. 117–133Google Scholar
- Balesdent J, Mariotti A (1996) Measurement of soil organic matter turnover using 13C natural abundance. In: Boutton TW, Yamasaki SI (eds) Mass spectrometry of soils Marcel Dekker. USA, New York, pp. 83–111Google Scholar
- Carnevali R (1994) Comunidades del distrito de los campos y del subdistrito de la planicie sedimentaria del éste. In: Fitogeografía de la provincia de Corrientes. Gobierno de la provincia de Corrientes - INTA, Corrientes, p 324Google Scholar
- Chapin FS, Matson PA, Mooney HA (2002) Principles of terrestrial ecosystem ecology. Springer, New YorkGoogle Scholar
- Chonè T, Andreux F, Correa JC, Volkoff B, Cerri CC (1991) Changes in organic matter in an Oxisol from the Central Amazonian forest during eight years as pasture determined by 13C isotopic composition. Elsevier, Amsterdam, pp. 397–405Google Scholar
- Christensen BT (1996) Matching measurable soil organic matter fractions with conceptual pools in simulation models of carbon turnover: revision of model structure. In: Powlson DS, Smith, P., Smith, J.U. (eds.) In: Evaluation of soil organic matter models. Berlin, Springer :143–159Google Scholar
- Cotrufo MF, Wallenstein MD, Boot CM, Denef K, Paul E (2013) The microbial efficiency-matrix stabilization (MEMS) framework integrates plant litter decomposition with soil organic matter stabilization: do labile plant inputs form stable soil organic matter? Glob Chang Biol 19(4):988–995CrossRefPubMedGoogle Scholar
- Davidson E, Ackerman I (1993) Changes in soil carbon inventories following cultivation of previously untilled soils. Biogeochemistry 20:161–193Google Scholar
- Epstein HE, Burke IC, Lauenroth WK (2002) Regional patterns of decomposition and primary production rates in the U.S. great plains. Ecology 83(2):320–327Google Scholar
- Erize FE, Dimitri MJ, Julio Leonardis RF, Biloni JS, Babarskas M, Gómez D, Haene E, Monteleone A, Ostrosky C (1997) Especies Forestales de la Argentina Oriental. In: El Nuevo libro del arbol, Tomo II. Buenos Aires, p 124Google Scholar
- Fisher MJ, Thomas RJ, Rao IM (1997) Management of tropical pastures in acid soil savannas of South America for carbon sequestration in the soil. In: Lal R, Kimble JM, Follet RF, Stewart BA (eds) Management of carbon sequestration in soil. CPC Press, Boca Raton, pp. 405–420Google Scholar
- Gomez IA, Gallopin GC (1991) Relationship between net primary productivity of terrestrial ecosystems around the world and some environmental factors. Estimacion de la productividad primaria neta de ecosistemas terrestres del mundo en relacion a factores ambientales 1(1): 24–40Google Scholar
- Henderson GS (1995) Soil organic matter: a link between forest management and productivity. In: Bigham JM, Bartels JM (eds) Carbon forms and functions in forests soils. Soil Science Society of America Inc., Madison, pp. 419–435Google Scholar
- Ito A, Oikawa T (2004) Global mapping of terrestrial primary productivity and light-use efficiency with a process-based model. In: Global environmental change in the ocean and on land. TERRAPUB, Tokyo, pp. 343–358Google Scholar
- Jenkinson DS, Meredith J, Kinyamario JI, Warren GP, Wong MTF, Harkness DD, Bol R, Coleman K (1999) Estimating net primary production from measurements made on soil organic matter. Ecology 80(8):2762–2773Google Scholar
- Lauenroth WK, Gill R (2003) Turnover of root systems. In: Root ecology. Springer, Berlin Heidelberg, pp 61–89Google Scholar
- Ligier HD, Matteio HR, Polo HL, Rosso JR (1988) Mapa de suelos de la provincia de Misiones In: INTA (ed) Atlas de suelos de la República Argentina. Buenos Aires, pp 107–154Google Scholar
- Malhi Y, Aragão LE, Metcalfe DB, Paiva R, Quesada CA, Almeida S, Anderson L, Brando P, Chambers JQ, Da Costa ACL, Hutyra LR, Oliveira P, Patiño S, Pyle EH, Robertson AL, Teixeira LM (2009) Comprehensive assessment of carbon productivity, allocation and storage in three Amazonian forests. Glob Chang Biol 15(5):1255–1274CrossRefGoogle Scholar
- Monteith JL (1972) Solar radiation and productivity in tropical ecosystems. J Appl Ecol 9:747–766Google Scholar
- Parodi RL (1964) Las regiones fitogeográficas argentinas. In: Enciclopedia Argentina de Agricultura y Ganadería. Buenos Aires, p 14Google Scholar
- Pérez CA, Goya JF, Bianchini F, Frangi JL, Fernandez R (2006) Productividad aérea y ciclo de nutrientes en plantaciones de Pinus taeda L. en el norte de la provincia de Misiones, Argentina. Interciencia 31(11):794–801Google Scholar
- Piñeiro G, Paruelo JM, Jobbágy EG, Jackson RB, Oesterheld M (2009) Grazing effects on belowground C and N stocks along a network of cattle exclosures in temperate and subtropical grasslands of South America. Glob Biogeochem Cycles 23(2)Google Scholar
- Post WM, Mann L (1990) Changes in soil organic carbon and nitrogen as a result of cultivation. In: Soils and the Greenhouse Effect (ed Bouw- man AF). JohnWiley & Sons, New York, pp 401-406Google Scholar
- Rezende CP, Cantarutti RB, Braga JM, Gomide JA, Pereira JM, Ferreira E, Tarré R, Macedo R, Alves BJR, Urquiaga S, Cadisch G, Giller KE, Boddey RM (1999) Litter deposition and disappearance in Brachiaria pastures in the Atlantic forest region of the south of Bahia, Brazil. Nutr Cycl Agroecosyst 54(2):99–112CrossRefGoogle Scholar
- Solomon D, Fritzsche F, Lehmann J, Tekalign M, Zech W (2002) Soil organic matter dynamics in the Subhumid Agroecosystems of the Ethiopian highlands: evidence from natural 13C abundance and particle-size fractionation. In 3:969–978Google Scholar
- Sollins P, Glassman C, Paul E, Swanston C, Lajtha K, Heil JW, Elliot ET (1999) Soil carbon and nitrogen pools and fractions. In: Robertson GP, Coleman DC, Bledsoe CS, Sollins P (eds) Standard soil methods for long-term ecological Reaserch. Oxford University Press, New York, p 437Google Scholar
- Soriano A, León RJC, Sala OE, Lavado RS, Deregibus VA, Cauhépé MA, Scaglia OA, Velázquez CA, Lemcoff JH (1992) Río de la Plata grasslands. In: Coupland RT (ed) Ecosystems of the world 8A. Natural grasslands. Introduction and western hemisphere. Elsevier, New York, pp. 367–407Google Scholar
- Sundaravalli M, Paliwal K (2000) Primary production and soil carbon dioxide emission in the semi-arid grazing lands of Madurai, India. Trop Grassl 34:14–20Google Scholar
- Yadvinder M, A LEOC, Daniel BM, Romilda P, Carlos AQ, Samuel A, Liana A, Paulo B, Jeffrey QC, da Costa ACL, Lucy R H, Paulo O, Sandra P, Elizabeth H P, Amanda L R, Liliane M T (2009) Comprehensive assessment of carbon productivity, allocation and storage in three Amazonian forests. Glob Chang Biol 15(5):1255–1274CrossRefGoogle Scholar
- Zhou T, Luo Y (2008) Spatial patterns of ecosystem carbon residence time and NPP-driven carbon uptake in the conterminous United States. Glob Biogeochem Cycles 22(3)Google Scholar