Land-use Changes Alter Energy and Water Balances on an African BrachiariaPasture Replacing a Native Savanna in the Orinoco llanos
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DOI: https://doi.org/10.30564/jasr.v2i2.558
Abstract:The seasonal changes in the energy balance after the substitution of a herbaceous savanna by a Brachiaria field located in the Orinoco lowlands were assessed over an entire year using the eddy covariance technique. Simultaneously, an herbaceous savanna was monitored as a control. This work provides evidence that the vegetation replacement lead to different patterns of energy and water balance. The seasonal trends of the latent heat flux (λE) to available energy (Ra) ratio tended to decrease as senescence increased due to seasonal influence of air humidity mole fraction deficit and soil water content on leaf area index (LAI) and surface conductance (gs). Therefore, the partitioning of the available energy depended on both climatological (i.e., solar radiation, volumetric soil water content and air humidity mole fraction deficit) and biological variables (i.e., conductance behavior and LAI) which were stress-induced. For the wet season, the seasonally averaged daily λE in the Brachiaria field (i.e., 0.8 ± 0.1 mm d-1) was 1.3-fold higher than that in the herbaceous savanna (i.e., 0.6 ± 0.1 mm d-1) (Mann-Whitney U-test). For the dry season, the value was 2.7 ± 0.6 and 2.2 ± 0.4 mm d-1, respectively, these means values were not significantly different. In the Brachiaria and herbaceous savanna stands, the annual evapotranspiration was 731 and 594 mm year-1, respectively, and the annual ratio of evapotranspiration to precipitation was 0.52 to 0.42 respectively. In Brachiaria field, the deep drainage was relatively lower (43% of total precipitation) than that in the herbaceous savanna stand (53%) leaving a similar amount of water to increase soil storage. The current shift in land cover decrease deep drainage and increased λE by water uptake from a pasture with high belowground phytomass and LAI.
References:[1] Grace, J., San Jose, J.J., Meir, P., Miranda, H.S. and Montes, R.A. “Productivity and carbon fluxes of tropical savannas”, J. Biogeogr, 2006, 33: 387-400 [2] Young, M.D. and Solbrig, O.T.. “The world`s Savannas Economic Driving Forces, Ecological Constraints and Policy Options for Sustainable Land Use”. Man and The Biosphere Series, UNESCO. Vol, 12. The Parthenon Publishing Group, UK, 1993. [3] San José, J.J., Montes, R.A., Grace, J., Nikonova, N. and Osio, A.. “Land-use changes alter radiative energy and water vapor fluxes of a tall-grass Andropogon field and a savanna-woodland continuum in the Orinoco lowlands”, Tree Physiol, 2008, 28: 425–435 [4] Loch, D.S.. “Brachiaria decumbens (signal grass). A review with particular reference to Australia”, Trop. Grasslands, 1977, 11: 144-157 [5] Thomas, D. and Grof, B.. “Some pastures species for the tropical savannas of South America”. III. Andropogon gayanus, Brachiaria spp. and Panicum maximum. Herb. Abstr, 1986, 56: 557–565 [6] Humphreys, L.R.. “Tropical Pastures and Fodder Crops”, second ed. Longman, New York, 1987. [7] CIAT.. “Informe anual del programa de pastos tropicales”, (CIAT: Cali, Colombia), 1992. [8] Miles, J.W., Maass, B.L., do Valle, C.B. and Kumble, V.. “Brachiaria: Biología, Agronomía y Mejoramiento”, pp. 312 (CIATEMBRAPA: Colombia), 1998. [9] Pizarro, E.A., do Valle, C.B., Keller-Grein, G., Schultze, R. and Zimmer, A.H.. “Experiencia regional con Brachiaria: Región de América Tropical-Sabanas”, In: Miles, J.W., Maass, B.L., do Valle, C.B., Kumble V. (Eds.), Brachiaria: Biología, Agronomía y Mejoramiento. CIAT–EMBRAPA, Colombia, 1998: 247–269. [10] San José, J.J., Nikonova, N. and Bracho, R.. “Comparison of factors affecting water transfer in a cultivated paleotropical grass (Brachiaria decumbens Stapt.) field and a neotropical savanna during the dry season of the Orinoco lowlands”, J. Appl. Meteorol, 1998, 37: 509–522 [11] Vera, R.A., Hoyos, P. and Moya, M.C.. “Pasture renovation practices of formers in the Neotropical savannahs”, Land Degrad. 1998, 9: 47–56 [12] Monteith, J.L. and Unworth, M.M.. “Principles of Environmental Physics”, second ed. Edward Arnold, London, 1990. [13] Verhoef, A., Allen, S.J., De Bruin, H.A.R., Jacobs, C.M.J. and Heusinkueld, B.G.. “Fluxes of carbon dioxide and water vapour from a Sahelian savanna”, Agri. Forest Meteorol, 1996, 80: 231–248. [14] Miranda, A.C., Miranda, H.S., Lloyd, J., Grace, J., Francey, R.J., McIntyre, J.A., Meir, P., Riggan, P., Lockwood, R. and Brass, J.. “Fluxes of carbon, water and energy over Brazilian cerrado: an analysis using eddy covariance and stable isotopes”, Plant Cell and Environment, 1997, 20: 315-328. [15] Cook, P.G., Hatton, T., Pidsley, D., Herczeg, A.L., Held, A.A., O`Grady, A.D. and Eamus, D.. “Water balance of a tropical woodland ecosystem, northern Australia: a combination of micro-meteorological, soil physical and groundwater chemical approaches”, J. Hydrol, 1998, 210: 161-177 [16] Eamus, D., Hutley, L.B. and O`Grady, A.P.. “Daily and seasonal patterns of carbon and water fluxes above a northern Australian savanna”, Tree Physiol, 2001, 21: 977-988. [17] Espinoza, J.. “Estudio de las series de suelo y levantamiento agrologico del campo experimental agrícola de sabana de Jusepin”, Escuela de Ingeniería Agronómica, Núcleo Monagas/Jusepin, Universidad de Oriente, 1970: 40. [18] Soil Survey Staff.. “Soil Taxonomy. A basic system of soil classification for making and interpreting soil survey”, USDA Agriculture Handbook No. 436. US Government Printing Office, Washington, 1975. [19] Fermín, M.A.J.. “Algunas relaciones suelo-agua de la Estación Experimental Agrícola de Sabana”, Trabajo de grado, Universidad de Oriente, Jusepin, Monagas, Venezuela, 1971. [20] McKell, C.M., Wilson, A.M. and Jones, M.B. “A flotational method for easy separation of roots from soil samples”, Agron, 1961, 53: 56-57 [21] Moncrieff, J., Monteny, B., Verhoef, A., Friborg, T., Kabat, P., de Bruin, H., Soegaard, H., Jarvis, P.G. and Taupin, J.D.. “Spatial and temporal variations in net carbon flux during HAPEX-Sahel”, J. Hydrol, 1997, 188–189: 563–588. [22] Aubinet, M., Grelle, A., Ibrom, A., Rannik, U., Moncrieff, J., Foken, T., Kowalski, A.S., Martin, P.H., Berbigier, P., Bernhofer, C., Clement, R., Elbers, J., Granier, A., Grünwald, T., Morgenstern, K., Pilegaard, K., Rebmann, C., Snijders, W., Valentini, and R., Vesala, T.. “ Estimates of the annual net carbon and water exchange of forests: the EUROFLUX methodology”, Adv. Ecol. Res, 2000, 30: 113–175. [23] Webb, E.K., Pearman, G.I. and Leuning, R.. “Correction of flux measurements for density effects due to heat and water vapour transfer”, Q. J. Roy. Meteor. Soc, 1980, 106: 85–100. [24] Fuchs, M. and Tanner, C.B.. “Calibration and field test of soil heat flux plates”, Soil Sci. Soc. Am. Pro, 1968, 32: 326-328 [25] Schmid, H.P. and Oke, T.R.. “Estimating the source area of a turbulent flux measurement over a patchy surface”, In: Proceedings of the Conference on Turbulence and Diffusion. American Meteorological Society, San Diego, 1988: 123–126. [26] Schuepp, P.H., Leclerc, M.Y., Macpherson, J.I. and Desjardins, R.L.. “Footprint prediction of scalar fluxes from analytical solutions of the diffusion equation”, Bound-Lay. Meteorol, 1990, 50: 355–373. [27] Richards, L.A.. “Methods of measuring soil moisture tension”, Soil Sci, 1949, 68: 95–112. [28] Falge, E., Baldocchi, D., Olson, R.J., Anthoni, P., Aubinet, M., Bernhofer, C., Burba, G., Ceulemans, R., Clement, R., Dolman, H., Granier, A., Gross, P., Grünwald. T., Hollinger, D., Jensen, N.O., Katul, G., Keronen, P., Kowalski, A., Ta Lai, C., Law, B.E., Meyers, T., Moncrieff, J., Moors, E., Munger, J.W., Pilegaard, K., Rannik, Ü., Rebmann, C., Suyker, A., Tenhunen, J., Tu, K., Verma, S., Vesala, T., Wilson, K. and Wofsy, S.. “Gap filling strategies for defensible annual sums of net ecosystem exchange”, Agri. Forest Meteorol, 2001, 107: 43–69. [29] Reichstein, M., Falge, E., Baldocchi, D., Papale, D., Aubinet, M., Berbigier, P., Bernhofer, C., Buchmann, N., Gilmanov, T., Granier, A., Grünwald, T., Havránková, K., Ilvesniemi, H., Janous, D., Knohl, A., Laurila, T., Lohila, A., Loustau, D., Matteucci, G., Meyers,T., Miglietta, F., Ourcival, J.M., Pumpanen, J., Rambal, S., Rotenberg, E., Sanz, M., Tenhunen, J., Seufert, G., Vaccari, F., Vesala, T., Yakir, D. and Valentini, R.. “On the separation of net ecosystem Exchange into assimilation and ecosystem respiration: review and improved algorithm”, Glob. Change Biol, 2005, 11: 1424–1439 [30] Reifsnyder WE, McNaughton KG. and Milford, J.R.. “Symbols, units, notation. A statement of journal policy”, Agri. Forest Meteorol, 1991, 54: 389–397. [31] Adams, R.S., Black, T.A. and Fleming, R.L.. “Evaporation and surface conductance in a high elevation, grass-covered forest clear cut”, Agr. Forest Meteorol, 1991, 56: 173-193. [32] Koenker, R. and Park, B.J.. “An interior point algorithm for nonlinear quantile regression”, J. Econometrics, 1994, 71: 265-283. [33] Code, B.S. and Noon, B.R.. “A gentle introduction to quantile regression for ecologist” Front. Ecol. Environ, 2003, 1: 412-420. [34] Thom, A.S.. “Momentum, mass and heat exchange of vegetation”, Q.J. Roy. Meteir. Soc, 1972, 98: 124-134. [35] Verma, S.B.. “Aerodynamic resistances to transfer of heat, mass and momentum”, in: Black, T.A., Splittelhouse, D.L., Novak, M.D., Price, D.T. (Eds.), Estimation of Areal Evapotranspiration. International Association of Hydrological Science, Wallingford, UK, 1989: 13–20 [36] Paulson, C.A.. “The mathematical representation of wind speed and temperature profiles in the unstable atmospheric surface layer”, J. Appl. Meteorol, 1970, 9: 857–861. [37] Garratt, J.R. and Hicks, B.B.. “Momentum, heat and water vapour transfer to and from natural and artificial surfaces”, Q. J. Roy. Meteor. Soc, 1973, 99: 680-687. [38] Kelliher, F.M., Leuning, R.and Schulze, E.D.. “Evaporation and canopy characteristics of coniferous forest and grasslands”, Oecology, 1993, 95: 153-163. [39] Kelliher, F.M., Leuning, R., Raupauch, M.R. and Schulze, E.D.. “Maximum conductances for evaporation from global vegetation types”, Agri. Forest Metorol, 1995, 73: 1-16. [40] McNaughton, K.G. and Jarvis, P.G.. “Predicting the effects of vegetation changes on transpiration and evaporation”. In: Kozlowski, T.T. (Ed.), Water Deficits and Plant Growth, Vol VII. Academic Press. New York, 1983: 1–47. [41] Jarvis, P.G. and McNaughton, K.G.. “Stomatal control of transpiration: scaling up from leaf to region”, Adv. Ecol. Res, 1986, 15: 1-49. [42] Stewart, J.B.. “Modelling surface conductance of pine forest”, Agri. Forest Meteorol, 1988, 43: 19–35 [43] Gash, J.H.C., Wallace, J.S., Lloyd, C.R., Dolman, A.J., Sivakumar, M.V.K. and Renard, C,. “Measurements of evaporation from fallow Sahelian savannah at the start of the dry season”, Q. J. Roy. Meteor. Soc, 1991, 117: 745-760 [44] Montgomery, D.C. and Peck, E.A.. “Introduction to Linear Regression Analysis”, John Wiley and Sons, New York, 1982. [45] Chow, V.T. and Kareliotis S.J.. “Analysis of stochastic hydrologic systems”, Water Resour. Res, 1970, 6: 1569-1582. [46] Sokal, R.R. and Rohlf, F.J.. “Biometry: the principles and practice of statistics” in biological research. Fourth ed. W.H. Freeman and Co. New York, 1995. [47] Meek, D.W. and Prueger, J.H.. “Solutions for three regression problems commonly found in meteorological data analysis”, In: Proceeding of the 23rd Conference on Agricultural Forest Meteorology. 1998: 141-145. (American Meteorological Society: Albuquerque) [48] Denmead, D.T. and Shaw, R.J.. “Availability of soil water to plants as affected by soil moisture content and meteorological conditions”, Agron. J, 1962, 54: 385-390. [49] Keenan, T., Rutledge, S., Carbone, R., Wilson, J., Takanashi, T., May, P., Tapper, N.J., Platt, M., Hacker, J., Skelsky, S., Moncrieff, M.W., Saito, K., Holland, G.J., Crook, A. and Cage, K.. “The marine continent thunderstorm experiment (MCTEX): overview and some results”, B. Am, Meteorol. Soc, 2000, 81: 2433-2455. [50] Xinmei, H., Lyons,T.J. and Smith, C.G.. “Meteorological impact of replacing native perennial vegetation with annual agricultural species”, Hydrological Processes, 1995, 9: 645-654. [51] Beringer, J., Hutley, L.B., Tapper, N.J., Coutts, A., Kerley, A and, O`Grady, A.P.. “Fire impacts on surface heat, moisture and carbon fluxes from a tropical savanna in north Australia”, Inter. J. Wildland Fire, 2003, 12: 333-340. [52] Maitelli, G.T. and Miranda, A.C.. “Evapotranspiracao e fluxos de energía no cerrado - estação chuvosa”, An. Acad. Bras. Cienc, 1991, 63: 265–272. [53] Miranda, A.C., Miranda, H.S., Lloyd, J., Grace, J., McIntyre, J.A., Meir, P., Riggan, P., Lockwood, R. and Brass, J.. “Carbon Dioxide Fluxes over a Cerrado sensu stricto in Central Brazil”, In: Gash, J.H.C., Nobre, C.A., Roberts, J.M., Victoria, R. (Eds.), In Amazonia Deforestation and Climate. John Wiley & Sons, Chichester, 1996: 353-363. [54] Santos, A.J., Silva, G.T., Miranda, H.S., Miranda, C. and Lloyd, J.. “Effects of fire on surface carbon, energy and water vapour fluxes over campo sujo savanna in Central Brazil”, Funct. Ecol, 2003, 17: 711–719. [55] Oliveira, R.S., Bezerra, L., Davidson, E.A., Pinto, F., Klink, C.A., Nepstad, D.C. and Moreira, A.. “Deep root function in soil water dynamics in cerrado savannas of Central Brazil”. Funct. Ecol, 2005, 19: 574–581. [56] Giambelluca, T.W., Scholz, F.G., Bucci, S.J., Meinzer, F.C., Goldstein, G., Hoffmann, W.A.,Franco, A.C. and Buchert, M.P.. “Evapotranspiration and energy balance of Brazilian savannas with contrasting tree density”, Agri. Forest Meteorol, 2009, 149: 1365-1376. [57] Santos, A.J., Quesada, C.A., da Silva, G.T., Maia, J.F., Miranda, H.S., Miranda, A. and Lloyd, L.. “High rates of net ecosystem carbon assimilation by Brachiaria pasture in the Brazilian cerrado”, Glob. Change Biol, 2004, 10: 877-885. [58] Hutley, L., O´Grady, A. and Eamus, D.. “Evapotranspiration from Eucalypt open-forest savanna of Northern Australia”, Funct. Ecol, 2000, 14: 183-194. [59] Bucci, S.J., Scholz, F.G., Goldstein, G., Hoffman, W.A., Meinzer, F.C. Franco, A.C., Giambelluca, T. and Miralles-Wilhelm F.. “Controls on stand transpiration and soil water utilization along a tree density gradient in a Neotropical savanna”, Agr. Forest Meteorol, 2008, 148: 839-849. [60] Baldocchi, D.D., Xu, L. and Kiang, N.Y.. “How plant functional-type, weather, seasonal drought, and soil physical properties alter water and energy fluxes of an oak-grass savanna and an annual grassland”, Agr. Forest Meteorol, 2004, 123: 13-39. [61] Lewis, D.C.. “Annual hydrologic response to watershed conversion from oak woodland to annual grassland”, Water Resour. Res, 1968, 4: 59-72. [62] Ramier, D., Boulan, N., Cappelaere, B., Timouk, F., Rabanit, M., Lloyd, C.R., Boubkraoui, S., Metayer, F., Descroix, L. and Wawrzyniak, V.. “Toward an understanding of coupled physical and biological processes in the cultivated Sahel. 1. Energy and water”, J. Hydrol, 2009, 375: 204–216. [63] Mattos, J.L., Gomide, J.A., Martinez, J. and Huaman, C.A.. “Crescimento de species do genero Brachiaria, sob déficit hídrico, em casa de vegetação”, Rev. Bras. Zootecn, 2005, 34: 746-754. [64] Bittman, S. and Simpson, G.M.. “Drought effects on water relations of three cultivated grasses”, Crop Sci, 1989, 29: 992-999. [65] Bagayoko, F., Yonkeu, S., Elbers, J. and Van de Griese, N.. “Energy partitioning over the West African savanna: Multi-year evaporation and surface conductance measurements in Eastern Burkina Faso”, J. Hydrol, 2007, 334: 545-559. [66] Fonseca, A.S.. “Identificación de los cuerpos silicosos de las gramíneas de la sabana de Trachypogon de los llanos Altos Centrales”, Bol. Soc. Venez. Ci. Nat, 1983, 141: 17-83. [67] Baruch, Z., Ludlow, M.M. and Davis, R.. “Photosynthetic responses of native and introduced C4 grasses from Venezuelan savannas”, Oecologia, 1985, 67: 288-293. [68] Eamus, D. and Cole, S.. “Diurnal and seasonal comparisons of assimilation, phyllode conductance and water potential, of three Acacia and one Eucalyptus species in the wet-dry tropics of Australia”, Aust. J. Bot, 1997, 45: 275-290. [69] Prior, L.D., Eamus, D. and Duff, G.. “Seasonal and diurnal patterns of carbon assimilation, stomatal conductance and leaf water potential” in Eucalyptus tetrodonta saplings in a wet-dry savanna in northern Australia, Aust. J. Bot, 1997, 45: 241–258. [70] Eamus, D., Myers, B., Duff, G. and Williams, D.. “Seasonal changes in photosynthesis of eight savanna tree species”, Tree Physiol, 1999, 19: 665–671. [71] Whitley, R., Taylor, D., Macinnis-Ng, C., Zeppel, M., Yunusa, I., O'Grady, A., Froend, R., Medlyn, B. and Eamus, D.. “Developing an empirical model of canopy water flux describing the common response of transpiration to solar radiation and VPD across five contrasting woodlands and forests”, Hydrol. Process, 2012. DOI: https://doi.org/10.1002/hyp.9280 [72] San José, J.J., Montes, R.. “Management effects on stocks and fluxes across the Orinoco savannas”, Forest Ecol. Manag, 2001, 150: 293-311. [73] Sellers, P.J., Randall, D.A., Collatz, G.J., Berry, J.A., Field, C.B., Dazlich, D.A., Zhang, C., Collelo, G.D. and Bounoua, L.. “A revised land surface parameterization (SiB2) for atmospheric GCMs. Part I: Model formulation”, J. Climate, 1996, 9: 676–705. [74] Ham, J.M. and Knapp, A.K.. “Fluxes of CO2, water vapour, and energy from a prairie ecosystem during the seasonal transition from carbon sink to carbon source”, Agri. Forest Meteorol, 1998, 89: 1-14. [75] Zeng, N. and Neelin, J.D.. “The role of vegetation-climate interaction and interannual variability in shaping the African savanna”, J. Climate, 2000, 13: 2665–2669. [76] Schaeffer, M., Eickhout, B., Hoog Wijk, M., Strengers, B., van Vuuren, D., Leemans, R. and Opteegh, T.. “CO2 and albedo climate impacts of extratropical carbon and biomass plantations”, Glob. Biogeochem. Cy. 20, GB2020, 2006. DOI: https://doi.org/10.1029/2005GB002581 [77] Joffre, R. and Rambal, S.. “How tree cover influences the water balance of Mediterranean rangelands”, Ecology, 1993, 74: 570-582. [78] Hoffmann, W.A. and Jackson, R.B.. “Vegetation-climate feedbacks in the conversion of tropical savanna to grassland”, J. Climate, 2000, 13: 1593-1602.