Effects of soil water regime and grazing on vegetation diversity and production in a hyperseasonal savanna in the Apure Llanos, Venezuela

Journal of Tropical Ecology

Volumn 20, Issue 2, 2004, Pages 209-220

  Sarmiento, Guillermo ^a,b   Pinillos, Marcela ^a   Da Silva, Marta Pereira ^a   Acevedo, Dimas ^a  

^a UNIVERSIDAD DE LOS ANDES   (Venezuela)

^b FEDERAL UNIVERSITY OF RIO DE JANEIRO   (Brazil)

Author keywords

Cattle grazing; Grasses; Hyperseasonal savanna; Primary production; Seasonal drought; Tropical grassland; Water excess

Indexed keywords

BIODIVERSITY; BIOMASS; GRAZING; PRIMARY PRODUCTION; SAVANNA; SEASONAL VARIATION; SOIL WATER; VEGETATION DYNAMICS;

SOUTH AMERICA; VENEZUELA;

AXONOPUS; AXONOPUS PURPUSII; BOS TAURUS; LEERSIA HEXANDRA; PANICUM; PANICUM LAXUM; PASPALUM; POACEAE;

EID: 1942542351     PISSN: 02664674     EISSN: None     Source Type: Journal    
DOI: 10.1017/S0266467403001299     Document Type: Article

References (34)

1. BELSKY, A. J. 1986. Does herbivory benefit plants? A review of the evidence. American Naturalist 127:870-892.
2. BELSKY, A. J. 1987. The effects of grazing: confounding of ecosystem, community, and organism scales. American Naturalist 129:777-783.
3. BLYDENSTEIN, J. 1967. Tropical savanna vegetation of the Llanos of Colombia. Ecology 48:1-15.
4. BONHAM, C. D. 1989. Methods of vegetation analysis. John Wiley & Sons, New York. 327 pp.
5. BULLA, L., PACHECO, J. & MIRANDA, R. 1980. Ciclo estacional de la biomasa verde, muerta y raices en una sabana inundada de estero en mantecal (Venezuela). Acta Científica Venezolana 31:339-344.
6. BULLOCK, J. M., FRANKLIN, J., STEVENSON, M. J., SILVERTOWN, J., COULSON, S. J., GREGORY, S. J. & TOFTS, R. 2001. A plant trait analysis of responses to grazing in a long-term experiment. Journal of Applied Ecology 38:253-267.
7. BURKE, I. C., LAUENROTH, W. K. & MILCHUNAS, D. G. 1996. Biogeochemistry of managed grasslands in the Central Grasslands of the U.S. Pp. 85-101 in Paustian. P. E. & Elliot, E. T. (eds). Organic Matter in U.S. Agroecosystems. CRC Press, Boca Raton, FL.
8. BURKE, I. C., LAUENROTH, W. K., RIGGLE, R., BRANNEN, P., MADIGAN, B. & BEARD, S. 1999. Spatial variability of soil properties in the shortgrass steppe: the relative importance of topography, grazing, microsite, and plant species in controlling spatial patterns. Ecosystems 2:422-438.
9. ECOSA. 1980. Estudio agrológico de gran visión: Estado Apure. Informe general. Ministerio del ambiente y de los Recursos Naturales Renovables, Caracas. 241 pp.
10. ETTER, A. 1998. Mapa general de ecosistemas de Colombia. Escala 1:2.000.000. Instituto Alexander Von Humboldt. Bogotá.
11. FAO. 1964. Reconocimiento edafológico de los Llanos Orientales, Colombia. II. La vegetación natural y la ganadería en los Llanos Orientales. FAO, Rome. 233 pp.
12. GILLON, D. 1983. The fire problem in tropical savannas. Pp. 617-641 in Bourlière, F. (ed). Ecosystems of the World. 13. Tropical savannas. Elsevier, Amsterdam.
13. GONZÁLEZ JIMÉNEZ, E. 1979. Primary and secondary productivity in flooded savannas. Pp. 620-625 in Tropical grazing land ecosystems. UNESCO, Paris.
14. KNAPP, A. K., BRIGGS, J. M. & KOELLIKER, J. K. 2001. Frequency and extent of water limitation to primary production in a mesic temperate grassland. Ecosystems 4:19-28.
15. LAMOTTE, M. 1982. Consumption and decomposition in tropical grassland ecosystems at Lamto, Ivory Coast. Pp. 415-429 in Huntley, B. J. & Walker, B. H. (eds). Ecology of tropical savannas. Springer-Verlag, Berlin.
16. LAUENROTH, W. K. 2000. Methods of estimating belowground net primary production. Pp. 58-71 in Sala, O. E., Jackson, R. B., Mooney. H. A. & Howarth, R. W. (eds). Methods in ecosystem science. Springer-Verlag, New York.
17. LAUENROTH, W. K., DODD, J. L. & SIMS, P. L. 1978. The effects of water and nitrogen induced stresses on plant community structure in a semiarid grassland. Oecologia 36:211-222.
18. LERICHE, H., LEROUX, X., GIGNOUX, J., TUZET, A., FRITZ, H., ABBADIE, L. & LOREAU, M. 2001. Which functional processes control the short-term effect of grazing on net primary production in grasslands? Oecologia 129:114-124.
19. MCNAUGHTON, S. J. 1979. Grazing as an optimization process: grass-ungulate relationships in the Serengeti. American Naturalist 113:691-703.
20. MCNAUGHTON, S. J. 1984. Grazing lawns: animals in herds, plant form, and coevolution. American Naturalist 124:863-886.
21. MCNAUGHTON, S. J. 1986. On plants and herbivores. American Naturalist 128:765-770.
22. MILCHUNAS, D. G. & LAUENROTH, W. K. 1993. Quantitative effects of grazing on vegetation and soils over a global range of environments. Ecological Monographs 63:327-366.
23. MILCHUNAS, D. G., SALA, O. E. & LAUENROTH, W. K. 1988. A generalized model of the effects of grazing by large herbivores on grassland community structure. American Naturalist 132:87-105.
24. PARUELO, J. M., LAUENROTH, W. K., BURKE, I. C. & SALA, O. E. 1999. Grassland precipitation-use efficiency varies across a resource gradient. Ecosystems 2:64-68.
25. PEARSON, C. J. & ISON, R. L. 1987. Agronomy of grassland systems. Cambridge University Press, Cambridge. 169 pp.
26. SARMIENTO, G. 1983. The savannas of tropical America. Pp. 245-288 in Bourlière, F. (ed.). Ecosystems of the World. 13. Tropical savannas. Elsevier, Amsterdam.
27. SARMIENTO, G. 1984. The ecology of neotropical savannas. Harvard University Press, Cambridge. 235 pp.
28. SARMIENTO, G. 1990. Ecología comparada de ecosistemas de sabanas en América del Sur. Pp. 15-56 in Sarmiento, G. (ed.). Las sabanas americanas. Aspectos de su biogeografía, ecologia y utilización. Fondo Editorial Acta Científica Venezolana, Caracas.
29. SARMIENTO, G. 1996. Biodiversity and water relations in tropical savannas. Pp. 61-75 in Solbrig, O. T., Medina, E. & Silva, J. F. (eds). Biodiversity and savanna ecosystem processes. A global perspective. Springer, Berlin.
30. SARMIENTO, G. & PINILLOS, M. 2000. A conceptual model relating ecological constraints to livestock production in tropical American seasonal savannas. Pp. 295-314 in Mander, U. & Jongman, R. H. G. (eds). Consequences of land use changes. WIT Press, Southampton.
31. SARMIENTO, G. & PINILLOS, M. 2001. Patterns and processes in a seasonally flooded tropical plain: the Apure Llanos, Venezuela. Journal of Biogeography 28:985-996.
32. SARMIENTO, G. & VERA, M. 1979. Composición, estructura, biomasa y producción primaria de diferentes sabanas en los Llanos Occidentales de Venezuela. Boletín Sociedad Venezolana de Ciencias Naturales 136:5-41.
33. SCHARGEL, R. & GONZÁLEZ, R. A. 1972. Estudio Agrológico Preliminar. Sectores Bruzual y Mantecal, Estado Apure. MOP, Venezuela. 144 pp.
34. WESTOBY, M. 1986. Mechanisms influencing grazing success for livestock and wild herbivores. American Naturalist 128:940-941.