Advertisement

Photosynthetica

, Volume 52, Issue 3, pp 358–370 | Cite as

Effect of the replacement of a native savanna by an African Brachiaria decumbens pasture on the CO2 exchange in the Orinoco lowlands, Venezuela

  • J. San José
  • R. Montes
  • N. Nikonova
  • J. Grace
  • C. Buendía
Original Papers
  • 157 Downloads

Abstract

In the Orinoco lowlands, savannas have been often replaced by pastures composed of the C4 grass, Brachiaria decumbens Stapf. We addressed following questions: (1) How does the replacement of the native vegetation affect CO2 exchange on seasonal and annual scales? (2) How do biophysical constraints change when the landscape is transformed? To assess how these changes affect carbon exchange, we determined simultaneously the CO2 fluxes by eddy covariance, and the soil CO2 efflux by a chamber-based system in B. decumbens and herbaceous savanna stands. Measurements covered a one-year period from the beginning of the dry season (November 2008) to the end of the wet season (November 2009). During the wet season, the net ecosystem CO2 exchange reached maximum values of 23 and 10 μmol(CO2) m−2 s−1 in the B. decumbens field and in the herbaceous savanna stand, respectively. The soil CO2 efflux for both stands followed a temperature variation during the dry and wet seasons, when the soil water content (SWC) increased above 0.087 m3 m−3 in the latter case. Bursts of CO2 emissions were evident when the dry soil experienced rehydration. The carbon source/sink dynamics over the two canopies differed markedly. Annual measurements of the net ecosystem production indicated that the B. decumbens field constituted a strong carbon sink of 216 g(C) m−2 y−1. By contrast, the herbaceous savanna stand was found to be only a weak sink [36 g(C) m−2 y−1]. About 53% of the gross primary production was lost as the ecosystem respiration. Carbon uptake was limited by SWC in the herbaceous savanna stand as evident from the pattern of water-use efficiency (WUE). At the B. decumbens stand, WUE was relatively insensitive to SWC. Although these results were specific to the studied site, the effect of land use changes and the physiological response of the studied stands might be applicable to other savannas.

Additional key words

Eddy covariance soil CO2 eflux water-use efficiency 

Abbreviations

APF

apparent photosynthetic flux

Da

humidity mole fraction deficit

F10

soil CO2 efflux at 10°C

Fs

soil CO2 efflux

GPP

gross primary production

LAI

leaf area index

NEE

net ecosystem CO2 exchange

NEF

net ecosystem flux

NEP

net ecosystem production

PPF

photosynthetic photon flux

Qi

photosynthetic photon flux density

Reco

ecosystem respiration

u*

mean friction velocity

WUE

water-use efficiency

αa

apparent quantum yield (i.e., initial slope)

λE

evapotranspiration flux

ΔSc

CO2 storage

SWC

soil water content

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Alvim, M.J., Botrel, M. de A., Verneque, R.da S., Salvati, J.A.: [Nitrogen application in accessions of Brachiaria. 1. Effect on dry matter production.] — Pasturas Tropicales 12: 2–6, 1990. [In Portuguese]Google Scholar
  2. Aubinet, M., Grelle, A., Ibrom, A., et al.: Estimates of the annual net carbon and water exchange of forests: the EUROFLUX methodology. — Adv. Ecol. Res. 30: 113–175, 2000.CrossRefGoogle Scholar
  3. Aubinet, M., Heinesch, B., Longdoz, B.: Estimation of the carbon sequestration by a heterogeneous forest: night flux corrections, heterogeneity of the site and inter-annual variability. — Glob. Change Biol. 8: 1053–1071, 2002.CrossRefGoogle Scholar
  4. Aubinet, M., Heinesch, B., Yernaux, M.: Horizontal and vertical CO2 advection in a sloping forest. — Bound-Lay. Meteorol. 108: 397–417, 2003.CrossRefGoogle Scholar
  5. Baldocchi, D.: A comparative study of mass and energy exchange over a closed (wheat) and an open (corn) canopy: II. Canopy CO2 exchange and water use efficiency. — Agr. Forest Meteorol. 67: 291–321, 1994.CrossRefGoogle Scholar
  6. Baldocchi, D., Meyers, T.: On using eco-physiological, micrometeorological and biogeochemical theory to evaluate carbon dioxide, water vapor and gaseous deposition fluxes over vegetation. — Agr. Forest Meteorol. 90: 1–25, 1998.CrossRefGoogle Scholar
  7. Bégué, A., Desprat, J.F., Imbernon, J., Baret, F.: Radiation use efficiency of pearl millet in the Sahelian zone. — Agr. Forest Meteorol. 56: 93–110, 1991.CrossRefGoogle Scholar
  8. Birch, H.F., Friend, M.T.: Humus decomposition in East African soils. — Nature 178: 500–501, 1956.CrossRefGoogle Scholar
  9. Black, C.C.: Photosynthetic carbon fixation in relation to net CO2 uptake. — Ann. Rev. Plant Phys. 24: 253–286, 1973.CrossRefGoogle Scholar
  10. Boulain, N., Cappelaere, B., Ramier, D., et al.: Towards an understanding of coupled physical and biological processes in the cultivated Sahel — 2. Vegetation and carbon dynamics. — J. Hydrol. 375: 190–203, 2009.CrossRefGoogle Scholar
  11. Bowling, D.R., McDowell, N.G., Bond, B.J., Law, B.E., Ehleringer, J.R.: 13C content of ecosystem respiration is linked to precipitation and vapor pressure deficit. — Oecologia 131: 113–124, 2002.CrossRefGoogle Scholar
  12. Brümmer, C., Papen, H., Wassmann, R., Brüggemann, N.: Fluxes of CH4 and CO2 from soil and termite mounds in South-Sudanian savanna of Burkina Faso (W. Africa). — Global Biogeochem. Cy.: doi:10.1029/2008GB003237, 2009.Google Scholar
  13. Burrows, W.H., Henry, B.K., Back, P.V., et al.: Growth and carbon stock change in eucalypt woodlands in northeast Australia: ecological and greenhouse sink implications. — Glob. Change Biol. 8: 769–784, 2002.CrossRefGoogle Scholar
  14. Chen, X., Eamus, D., Hutley, L.B.: Seasonal patterns of soil carbon dioxide efflux from a wet-dry tropical savanna of northern Australia. — Aust. J. Bot. 50: 43–51, 2002.CrossRefGoogle Scholar
  15. Chen, X., Hutley, L.B., Eamus, D.: Carbon balance of a tropical savanna in northern Australia. — Oecologia 137: 405–416, 2003.CrossRefPubMedGoogle Scholar
  16. Cox, G.W.: Laboratory Manual of General Ecology. Pp. 272. W.O.C., Iowa 1972.Google Scholar
  17. Craine, J.M., Wedin, D.A., Chapin, F.S.: Predominance of ecophysiological controls on soil CO2 flux in a Minnesota grassland. — Plant Soil 207: 77–86, 1999.CrossRefGoogle Scholar
  18. Davidson, E.A., Beck, E., Boone, R.D.: Soil water content and temperature as independent or confound factors controlling soil respiration in a temperature mixed hardwood forest. — Glob. Change Biol. 4: 217–227, 1998.CrossRefGoogle Scholar
  19. Du, Y.C., Kawamitsu, Y., Nose, A., et al.: Effects of water stress on carbon exchange rate and activities of photosynthetic enzyme in leaves of sugarcane (Saccharum sp.). — Aust. J. Plant Physiol. 23: 719–726, 1996.CrossRefGoogle Scholar
  20. Eamus, D., Hutley, L.B., O’Grady, A.P.: Daily and seasonal patterns of carbon and water fluxes above a north Australian savanna. — Tree Physiol. 21: 977–988, 2001.CrossRefPubMedGoogle Scholar
  21. Falge, E., Baldocchi, D., Olson, R., et al.: Gap filling strategies for defensible annual sums of net ecosystem exchange. — Agr. Forest Meteorol. 107: 43–69, 2001.CrossRefGoogle Scholar
  22. Frouin, R., Pinker, R.T.: Estimating photosynthetically Active Radiation (PAR) at the Earth’s surface from satellite observations. — Remote Sens. Environ. 51: 98–107, 1995.CrossRefGoogle Scholar
  23. Grace, J., Lloyd, J., Miranda, A.C., Miranda, H., Gash, J.H.C.: Fluxes of carbon and water vapour over a C4 pasture in southwestern Amazonia (Brazil). — Aust. J. Plant Physiol. 25: 519–530, 1998.CrossRefGoogle Scholar
  24. Grace, J., Malhi, Y., Lloyd, J., et al.: The use of eddy covariance to infer the net carbon dioxide uptake of Brazilian rain forest. — Glob. Change Biol. 2: 209–217, 1996.CrossRefGoogle Scholar
  25. Griffiths, E., Birch, H.F.: Microbiological changes in freshly moistened soil. — Nature 189: 424, 1961.CrossRefGoogle Scholar
  26. Hanan, N.P., Kabat, P., Dolman, A.J., Elbers, J.A.: Photosynthesis and carbon balance of a Sahelian fallow savanna. — Glob. Change Biol. 4: 523–538, 1998.CrossRefGoogle Scholar
  27. Hanson, P.J., Wullschleger, S.D., Bohlman, S.A., Todd, D.E.: Seasonal and topographic patterns of forest floor CO2 efflux from an upland oak forest. — Tree Physiol. 13: 1–15, 1993.CrossRefPubMedGoogle Scholar
  28. Hedges, J.I., Clark, W.A., Quay, P.D., et al.: Compositions and fluxes of particulate organic material in the Amazon River. — Limnol. Oceanogr. 31: 717–738, 1986.CrossRefGoogle Scholar
  29. Hipps, L.E., Asrar, G., Kanemasu, E.T.: Assessing the interception of photosynthetically active radiation in winter wheat. — Agr. Meteorol. 28: 253–259, 1983.CrossRefGoogle Scholar
  30. Hunt, J.E., Kelliher, F.M., McSeveny, T.M., Byers, J.N.: Evaporation and carbon dioxide exchange between the atmosphere and a tussock grassland during a summer drought. — Agr. Forest Meteorol. 111: 65–82, 2002.CrossRefGoogle Scholar
  31. IPCC: Climate change: the IPCC Scientific Assessment. — In: Houghton, J.T., Jenkins, G.J., Ephraums, J.J. (ed.): Report by Working Group I Pp. 410. Cambridge University Press, Cambridge, New York, and Melbourne 1990.Google Scholar
  32. IPCC: Intergovermental panel on climate change. climate change 2001. — In: Watson, R.T. and the Core Writing Team (ed.): Synthesis Report. Third Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge Univ. Press, New York 2001.Google Scholar
  33. Jackson, M.L.: Soil Chemical Analysis. Pp. 380. Prentice, New York 1958.Google Scholar
  34. Jackson, R.B., Jobbagy, E.G., Avissar, R., et al.: Trading water for carbon with biological carbon sequestration. — Science 310: 1944–1947, 2005.CrossRefPubMedGoogle Scholar
  35. Kaimal, J.C., Finnigan, J.J.: Atmospheric Boundary Layer Flows. Their Structure and Measurement. Pp. 289. Oxford University Press, Oxford 1994.Google Scholar
  36. Kruijt, B., Elbers. J.A., von Randow, C., et al.: The robustness of eddy correlation fluxes for Amazon rain forest conditions. — Ecol. Appl. 14: S101–S113, 2004.CrossRefGoogle Scholar
  37. Lal, A., Edwards, G.E.: Analysis of inhibition of photosynthesis under water stress in the C4 species Amaranthus cruentus and Zea mays: electron transport, CO2 fixation and carboxylation capacity. — Funct. Plant Biol. 23: 403–412, 1996.Google Scholar
  38. Lapointe, S.L., Miles, J.W.: Germplasm case study: Brachiaria species. — In: Miles, J.W., Maass, B.L., do Valle, C.B., Kumble, V. (ed.): CIAT Pastures for the Tropical Lowlands: CIAT?s Contribution. Pp 43–55. CIAT, Cali, Colombia, 1992.Google Scholar
  39. Le Roux, X., Mordelet, P.: Leaf and canopy CO2 assimilation in a West African humid savanna during the early growing season. — J. Trop. Ecol. 11: 529–545, 1995.CrossRefGoogle Scholar
  40. Leuning, R., Cleugh, H.A., Zegelin, S.J., Hughes, D.: Carbon and water fluxes over a temperate Eucalyptus forest and a tropical wet/dry savanna in Australia: measurements and comparison with MODIS remote sensing estimates. — Agr. Forest Meteorol. 129: 151–173, 2005.Google Scholar
  41. Lira, M.D., Farias, I., Fernandes, A.D.M., Soares, L.M., Dubeux, J.C.B.: Response stability of signal grass (Brachiaria decumbens Stapf.) with increasing nitrogen and phosphorus levels. — Pesqui. Agropecu. Bras. 29: 1151–1157, 1994.Google Scholar
  42. Liski, J., Ilvesniemi, H., Mäkelä, A., Westman, C.J.: CO2 emissions from soil in response to climate warming are overestimated. The decomposition of old soil organic matter is tolerant of temperature. — Ambio 28: 171–174, 1999.Google Scholar
  43. Liu, X.Z., Wan, S.Q., Su, B., Hui, D.F., Luo, Y.Q.: Response of soil CO2 efflux to water manipulation in a tallgrass prairie ecosystem. — Plant Soil 240: 213–223, 2002.CrossRefGoogle Scholar
  44. Lloyd, C.R.: The CO2 dependence of photosynthesis, plant growth responses to elevated CO2 concentrations and their interaction with soil nutrient status, II. Temperate and boreal forest productivity and the combined effects of increasing CO2 concentrations and increased nitrogen deposition at a global scale. — Funct. Ecol. 13: 439–459, 1999.CrossRefGoogle Scholar
  45. Lloyd, J., Taylor, J.A.: On the temperature dependence of soil respiration. — Funct. Ecol. 8: 315–323, 1994.CrossRefGoogle Scholar
  46. Luo, Y.Q., Jackson, R.B., Field, C.B., Mooney, H.A.: Elevated CO2 increases belowground respiration in California grasslands. — Oecologia 108: 130–137, 1996.CrossRefGoogle Scholar
  47. McKell, C.M., Wilson, A.M., Jones, M.B.: A flotational method for easy separation of roots from soil samples. — Agron. J. 53: 56–57, 1961.CrossRefGoogle Scholar
  48. Meir, P., Grace, J., Lloyd, J., Miranda, A.C.: Soil respiration in a rain forest in Amazonia, and in cerrado in Central Brazil. — In: Gash, J.H.C., Nobre, C.A., Roberts, J.M., Victoria, R.L. (ed.): Amazonian Deforestation and Climate. Pp. 319–329. John Wiley & Sons, UK 1996.Google Scholar
  49. Meyers, T.P.: A comparison of summertime water and CO2 fluxes over rangeland for well watered and drought conditions. — Agr. Forest Meteorol. 106: 205–214, 2001.CrossRefGoogle Scholar
  50. Miles, J.W., Lapointe S.L.: Regional germplasm evaluation: A portfolio of germplasm options for the major ecosystems of tropical America. — In: Miles, J.W., Maass, B.L., do Valle, C.B., Kumble, V. (ed.):. Pastures for the Tropical Lowlands: CIAT?s Contribution. Pp 43–55. CIAT, Cali, Colombia, 1992.Google Scholar
  51. Miles, J.W., Maass, B.L., do Valle, C.B., Kumble, V.: [Brachiaria: Biology, Agronomy and Improvement.]. Pp. 312. CIAT-EMBRAPA, Colombia 1998. [In Spanish]Google Scholar
  52. Miranda, A.C., Miranda, H.S., Lloyd, J., et al..: Fluxes of carbon, water and energy over Brazilian cerrado: an analysis using eddy covariance and stable isotopes. — Plant Cell Environ. 20: 315–328, 1997.CrossRefGoogle Scholar
  53. Moncrieff, J.B., Monteny, B., Verhoef, A., et al.: Spatial and temporal variations in net carbon flux during HAPEX-Sahel. — J. Hydrol. 189: 563–588, 1997.CrossRefGoogle Scholar
  54. Monteiro, J.M.: [CO2 fluxes in a cerrado sensu stricto.] — Master Dissertation, Univ. Brasilia, Brasilia 1995. [In Portuguese]Google Scholar
  55. Monteny, B.A., Lhomme, J.P., Chehbouni, A., et al.: The role of the Sahelian biosphere on the water and the CO2 cycle during the HAPEX-Sahel Experiment. — J. Hydrol. 189: 516–535, 1997.CrossRefGoogle Scholar
  56. Mullenax, C.: [Adequacy and management of natural grasslands in the high plains of the Eastern Plains of Colombia.] — Carta Agraria 278: 2, 1979. [In Spanish]Google Scholar
  57. Parsons, J.J.: Spread of African grasses to the American tropics. — J. Range Manage. 25: 12–17, 1972.CrossRefGoogle Scholar
  58. Pla Sentís, I.: [Methodology for the physical characterization to diagnose problems in management and conservation of soils in tropical conditions.] — Graduate course in Soil Science, UCV. Pp 112. Maracay 1977. [In Spanish]Google Scholar
  59. Raich, J.W., Schlesinger, W.H.: The global carbon dioxide flux in soil respiration and its relationship to vegetation and climate. — Tellus B 44: 81–99, 1992.CrossRefGoogle Scholar
  60. Rao, I.M., Kerridge, P.C., Macedo, M.C.M.: [Nutritional requirements and adaptation to acid soils Brachiaria species.] — In: Miles, J.W., Maass, B.L., do Valle, C.B., Kumble, V. (ed.): [Brachiaria: Biology, Agronomy and Improvement]. Pp. 58–78. CIAT, EMBRAPA, Colombia 1998. [In Spanish]Google Scholar
  61. Reichstein, M., Falge, E., Baldocchi, D., et al.: On the separation of net ecosystem exchange into assimilation and ecosystem respiration: review and improved algorithm. — Glob. Change Biol. 11: 1424–1439, 2005.CrossRefGoogle Scholar
  62. Ribeiro, J.P., Walter, B.M.: [Vegetation physiognomies of the Cerrado biome]. — In: Sano, S.M., de Almeida, S.P. (ed.): [Cerrado: Environment and Flora.] Pp. 89–168. EMBRAPACPAC, Planaltina, Brazil 1998. [In Portuguese]Google Scholar
  63. Ruimy, A., Jarvis, P.G., Baldocchi, D.D., Saugier, B.: CO2 fluxes over plant canopies and solar radiation: a review. — Adv. Ecol. Res. 26: 1–68, 1995.CrossRefGoogle Scholar
  64. San José, J.J.: Mass and energy transfer within and between burned and unburned savanna environments.— Int. J. Wildland Fire 2: 153–160, 1992.CrossRefGoogle Scholar
  65. San José, J.J.: Contribution of rangelands to animal production in the tropics. — In: Sotomayor-Rios, A., Pitman, W.D. (ed.): Tropical Forage Plants: Development and Use. Pp. 269–294. CRC Press, New York 2001.Google Scholar
  66. San José, J.J., Bracho, R., Montes, R., Nikonova, N.: Comparative energy exchange from cowpeas [Vigna unguiculata (L.) Walp cvs. TC-9-6 and M-28-6-6] with differences in canopy architectures and growth durations at the Orinoco llanos. — Agr. Forest Meteorol. 116: 197–219, 2003.CrossRefGoogle Scholar
  67. San José, J.J., Montes, R.: Resource apportionment and net primary production outcome across the Orinoco savanna-woodland continuum. — Acta Oecol. 32: 243–253, 2007.CrossRefGoogle Scholar
  68. San José, J.J., Montes, R., Grace, J., Nikonova, N.: Land-use changes alter CO2 flux patterns of a tall-grass Andropogon field and a savanna-woodland continuum in the Orinoco lowlands. — Tree Physiol. 28: 437–450, 2008.CrossRefPubMedGoogle Scholar
  69. Santos, A.J.B.: [Fluxes of energy, carbon and water in a vegetation of campo sujo.] — Master Dissertation, Univ. Brasilia, Brasilia 1999. [In Portuguese]Google Scholar
  70. Santos, A.J.B., Da Silva, G.T., Miranda, H.S., Miranda, A.C., Lloyd, J.: Effects of fire on surface carbon, energy and water vapour fluxes over campo sujo savanna in Central Brazil. — Funct. Ecol. 17: 711–719, 2003.CrossRefGoogle Scholar
  71. Santos, A.J.B., Quesada, C.A., Da Silva, et al.: High rates of net ecosystem carbón assimilation by Brachiaria pasture in the Brazilian cerrado. — Glob. Change Biol. 10: 877–885, 2004.CrossRefGoogle Scholar
  72. Schuepp, P.H., Leclerc, M.Y., MacPherson, J.I., Desjardin, R.L.: Footprint prediction of scalar fluxes from analytical solutions of the diffusion equation. — Bound.-Lay. Meteorol. 50: 353–373, 1990.CrossRefGoogle Scholar
  73. Sotta, E.D., Meir, P., Malhi, Y., Nobre, A.D., Hodnett, M.: Soil CO2 efflux in a tropical forest in the central Amazon. — Glob. Change Biol. 10: 601–617, 2004.CrossRefGoogle Scholar
  74. Stewart, W.M.: Balanced fertilization increases water use efficiency. News and views. A regional newsletter published by Potash & Phosphate Institute (PPI). Pp. 2, www.ppi-far.org. Lubbocks, Texas 2001.Google Scholar
  75. Tohmé, J., Palacios, N., Lenis, S., Roca, W.: [Applications of biotechnology to Brachiaria genus.] — In: Miles, J.W., Maass, B.L., do Valle, C.B., Kumble, V. (ed.): [Brachiaria: Biology, Agronomy and Improvement.] Pp. 216–225. CIATEMBRAPA, Cali, Colombia 1998. [In Spanish]Google Scholar
  76. Veenendaal, E.M., Kolle, O., Lloyd, J.: Seasonal variation in energy fluxes and carbon dioxide exchange for a broad-leaved semi-arid savanna (Mopane woodland) in Southern Africa. — Glob. Change Biol. 10: 318–328, 2004.CrossRefGoogle Scholar
  77. Veenendaal, E.M., Shuschu, D.D., Scurlock, J.M.O.: Responses to shading of seedling of savanna grasses (with different C4 photosynthetic pathway) in Botswana. — J. Trop. Ecol. 9: 213–229, 1993.CrossRefGoogle Scholar
  78. Verhoef, A., Allen, S.J., Lloyd, C.R.: Seasonal variation of surface energy balances over two Sahelian surfaces. — Int. J. Climatol. 19: 1267–1277, 1999.CrossRefGoogle Scholar
  79. Vourlitis, G., Priante, N., Hayashi, M.M.S., et al.: Seasonal variations in the net ecosystem CO2 exchange of a mature Amazonian transitional tropical forest (cerradao). — Funct. Ecol. 15: 388–395, 2001.CrossRefGoogle Scholar
  80. Walkley, A.: A critical examination of a rapid method for determining organic carbon in soils-effect of variations in digestion conditions and of inorganic soil constituents. — Soil Sci. 63: 251–264, 1947.CrossRefGoogle Scholar
  81. Williams, C.A., Albertson, J.D.: Soil moisture controls on canopy-scale and carbon fluxes in an African savanna. — Water Resour. Res. doi:10.1029/2004WR003208, 2004.Google Scholar
  82. Wilsey, B.: Clonal plants in a spatially heterogeneous environment: effects of integration on Serengeti grassland response to defoliation and urine-hits from grazing mammals. — Plant Ecol. 159: 15–22, 2002.CrossRefGoogle Scholar
  83. Zepp, R.G., Miller, W.L., Burke, R.A., Parsons, D.A.B., Scholes, M.C.: Effects of moisture and burning on soil-atmosphere exchange of trace carbon gases in a southern African savanna. — J. Geophys. Res.-Atmos. 101: 23699–23706, 1996.CrossRefGoogle Scholar

Copyright information

© The Institute of Experimental Botany 2014

Authors and Affiliations

  • J. San José
    • 1
  • R. Montes
    • 2
  • N. Nikonova
    • 1
  • J. Grace
    • 3
  • C. Buendía
    • 1
  1. 1.Ecology CenterVenezuelan Institute for Scientific ResearchCaracasVenezuela
  2. 2.Environment Studies DepartamentSimón Bolívar UniversityCaracasVenezuela
  3. 3.School of GeoSciencesThe University of EdinburghEdinburghUK

Personalised recommendations