Hostname: page-component-7c8c6479df-p566r Total loading time: 0 Render date: 2024-03-29T00:28:39.935Z Has data issue: false hasContentIssue false

Dissecting biomass dynamics in a large Amazonian forest plot

Published online by Cambridge University Press:  01 September 2009

Renato Valencia*
Affiliation:
Laboratorio de Ecología de Plantas y Herbario QCA, Escuela de Ciencias Biológicas, Pontificia Universidad Católica del Ecuador, Apartado 17-01-2184, Quito, Ecuador
Richard Condit
Affiliation:
Global Forest Observatory Network, Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Balboa, Ancón, Panamá, República de Panamá
Helene C. Muller-Landau
Affiliation:
Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Balboa, Ancon, Panamá, República de Panamá
Consuelo Hernandez
Affiliation:
Laboratorio de Ecología de Plantas y Herbario QCA, Escuela de Ciencias Biológicas, Pontificia Universidad Católica del Ecuador, Apartado 17-01-2184, Quito, Ecuador
Hugo Navarrete
Affiliation:
Laboratorio de Ecología de Plantas y Herbario QCA, Escuela de Ciencias Biológicas, Pontificia Universidad Católica del Ecuador, Apartado 17-01-2184, Quito, Ecuador

Abstract:

Above-ground biomass (AGB) is increasing in most of the Amazon forests. One hypothesis is that forests are responding to widespread and intense human intervention prior to the European conquest (>500 y ago). In this study we confront this hypothesis with changes in AGB over 6.3 y in a large western Amazonian forest plot (>150 000 shrubs and trees and 1100 species with dbh ≥ 10 mm in 25 ha). We examined AGB flux in different habitats and across diameter classes. The forest lost small stems (4.6%), gained large trees (2.6%), and gained biomass (0.7%). The change in AGB stock was due entirely to this upward shift in size leading to more canopy trees and fewer saplings after just 6 y. Across habitats, the biggest increment in biomass was in the secondary-forest patch (3.4% y−1) which we know was cleared about 27 y ago, whereas mature forest on ridges and valleys had small increases (0.10% and 0.09% y−1, respectively). In both censuses, AGB stocks were >50% higher on the ridge than in the valley while relative growth and mortality were higher in the valley. Mean wood specific gravity (WSG) decreased with increasing diameter class; WSG did not change much between censuses in mature forests and did not contribute to the change in AGB stocks. Our forest increased its standing biomass, but far less than the average reported for other Amazonian forests (i.e. 0.30 vs. 0.98 Mg ha−1 y−1). We find no evidence to support the notion that this forest is recovering from long-past human intervention. Instead of a long-term recovery, we believe the forest changed in response to natural fluctuations of the environment (e.g. changes in precipitation, higher CO2), windstorms or other more recent events. The significant differences in AGB stocks between valley and ridge suggest that the terra firme forests are a mosaic of natural habitats, and that this mosaic is in part responsible for the variation in biomass stocks detected in Amazonian terra firme forests.

Resumen: La biomasa aérea de la mayoría de los bosques amazónicos está incrementando. Una hipótesis es que los bosques están respondiendo a un disturbio humano intenso y ampliamente distribuido, anterior a la llegada de los conquistadores europeos (>500 años atrás). En este estudio se confronta esta hipótesis con los cambios en biomasa encontrados en 6.3 años en una parcela de gran escala de la Amazonia occidental (>150.000 arbustos y árboles con diámetro a la altura del pecho ≥10 mm y 1100 especies en 25 ha). Los resultados se examinan por categorías de diámetro y hábitat. En este período el bosque perdió tallos pequeños (4.6%), ganó árboles grandes (2.6%) y ganó biomasa (0.7%). La ganancia en biomasa fue debida enteramente al incremento de árboles de gran tamaño que significó más árboles de dosel y menos juveniles en apenas 6 años. Entre los hábitats, el mayor incremento en biomasa se encontró en un parche de bosque secundario de colina (3.4%/año), cuya edad es de 27 años, mientras el bosque maduro de las colinas y los valles incrementó escasamente (0.10% y 0.09%/año, respectivamente). Tanto al inicio como al final del estudio, el stock de biomasa fue >50% más grande en la colina que en el valle mientras que el crecimiento y la mortalidad relativa fueron mayores en el valle. La media de la gravedad específica de la madera (GEM) fue menor a mayor clase diamétrica; en el bosque maduro, el cambio en la GEM fue insignificante y no contribuyó al aumento en stocks de biomasa. El bosque incrementó la biomasa aérea pero mucho menos que el promedio reportado para otros bosques amazónicos (i.e. 0.30 vs. 0.98 Mg ha−1/año). No se encontró evidencia que apoye la noción de que el bosque se está recuperando de un disturbio de gran escala ocurrido en el pasado. En su lugar, se cree que el bosque cambió en respuesta a fluctuaciones naturales del ambiente (e.g. cambios en precipitación, mayor concentración de CO2), vendavales u otro tipo de eventos más recientes. La diferencia significativa en los stocks de biomasa encontrada entre el valle y la colina sugiere que la tierra firme es un mosaico de hábitats naturales y que este mosaico podría explicar en parte la variación encontrada en los stocks de biomasa de bosques amazónicos de tierra firme.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

LITERATURE CITED

ALVES, D. S., SOARES, J. V., AMARAL, S., MELLO, E. M. K., ALMEIDA, S. A. S., FERNANDES, DA, SILVA, O. & SILVEIRA, A. 1997. Biomass of primary and secondary vegetation in Rondônia, Western Brazilian Amazon. Global Change Biology 3:451461.Google Scholar
BAKER, T. R., PHILLIPS, O. L., MALHI, Y., ALMEIDA, S., ARROYO, L., DI FIORE, A., ERWIN, T., HIGUCHI, N., KILLEEN, T. J., LAURENCE, S. G., LAURENCE, W. F., LEWIS, S., MONTEAGUDO, A., NEILL, D. A., NÚÑEZ, P., PITMAN, N. C. A., SILVA, J. N. M. & VÁSQUEZ, R. 2004. Increasing biomass in Amazonian forest plots. Philosophical Transactions of the Royal Society B 359:353365.Google Scholar
BROWN, S. & LUGO, A. 1990. Tropical secondary forests. Journal of Tropical Ecology 6:132.Google Scholar
BUSH, M. & SILMAN, M. 2007. Amazonian exploitation revisited: ecological asymmetry and the policy pendulum. Frontiers in Ecology and Environment 5:457465.Google Scholar
CHAVE, J., ANDALO, C., BROWN, S., CAIRNS, M. A., CHAMBERS, J. Q., EAMUS, D., FÖLSTER, H., FROMARD, F., HIGUCHI, N., KIRA, T., LESCURE, J.-P., NELSON, W., OGAWA, H., PUIG, H., RIÉRA, B. & YAMAKURA, T. 2005. Tree allometry and improved estimation of carbon stocks and balance in tropical forests. Oecologia 145:8799.Google Scholar
CHAVE, J., CONDIT, R., MÜLLER-LANDAU, H. C., THOMAS, S. C., ASHTON, P. S., BUNYAVEJCHEWIN, S., CO, L. L., DATTARAJA, H. S., DAVIES, S. J., ESUFALI, S., EWANGO, C. E. N., FEELEY, K. J., FOSTER, R. B., GUNATILLEKE, N., GUNATILLEKE, S., HALL, P., HART, T. B., HERNÁNDEZ, C., HUBBELL, S. P., ITOH, A., KIRATIPRAYOON, S., LAFRANKIE, J. V., LOO, DE, LAO, S., MAKANA, J.-R., NOOR, M. N. S., RAHMAN KASSIM, A., SAMPER, C., SUKUMAR, R., SURESH, H. S., TAN, S., THOMPSON, J., TONGCO, M. D. C., VALENCIA, R., VALLEJO, M., VILLA, G., YAMAKURA, T., ZIMMERMAN, J. K. & LOSOS, E. C. 2008. Assessing evidence for a pervasive alteration in tropical tree communities. PLOS Biology 6:455462.CrossRefGoogle Scholar
CONDIT, R. 1998. Tropical forest census plots. Springer-Verlag, Berlin. 211 pp.Google Scholar
CONDIT, R., HUBBELL, S. P. & FOSTER, R. 1995. Mortality rates of 205 neotropical tree and shrub species and the impact of a severe drought. Ecological Monographs 65:419439.Google Scholar
CONDIT, R., SALOMON, A., HERNÁNDEZ, A., PÉREZ, R., LAO, S., ANGEHR, G., HUBBELL, S. P. & FOSTER, R. B. 2004. Tropical forest dynamics across a rainfall gradient and the impact of an El Niño dry season. Journal of Tropical Ecology 20:5172.Google Scholar
FICHTLER, E., CLARK, D. A. & WORBES, M. 2003. Age and long-term growth of trees in an old-growth tropical rain forest based on analyses of tree rings and 14C. Biotropica 35:306317.Google Scholar
GRACE, J., LLOYD, J., McINTYRE, J., MIRANDA, A. C., MEIR, P., MIRANDA, H. S., NOBRE, C., MONCRIEFF, J., MASSHEDER, J., MALHI, Y., WRIGHT, I. & GASH, J. 1995. Carbon dioxide uptake by an undisturbed tropical rain forest in southwest Amazonia 1992 to 1993s. Science 270:778780.Google Scholar
HECKENBERGER, M. J., CHRISTIAN RUSSELL, J., TONEY, J. R. & SCHMIDT, M. J. 2007. The legacy of cultural landscapes in the Brazilian Amazon: implications for biodiversity. Philosophical Transactions of the Royal Society B 362:197208.Google Scholar
HUGHES, R. F., KAUFFMAN, J. & JARAMILLO, V. J. 1999. Biomass, carbon, and nutrient dynamics of secondary forests in a humid tropical region of Mexico. Ecology 80:18921907.Google Scholar
JOHN, R., DALLING, J. W., HARMS, K. E., YAVITT, J. B., STALLARD, R. F., MIRABELLO, M., HUBBELL, S. P., VALENCIA, R., NAVARRETE, H., VALLEJO, M. & FOSTER, R. B. 2007. Soil nutrients influence spatial distributions of tropical species. Proceedings of the National Academy of Sciences 104:864869.Google Scholar
LEWIS, S. L., MALHI, Y. R. & PHILLIPS, O. L. 2004. Fingerprinting the impacts of global change on tropical forests. Philosophical Transactions of the Royal Society B 359:437462.Google Scholar
NETHERLY, P. 1997. Loma y ribera: patrones de asentamiento prehistórico en la Amazonía ecuatoriana. Fronteras de la Ciencia 1:354.Google Scholar
NEWSON, L. 1996. The population of the Amazon basin in 1492: a view from the Ecuadorian headwaters. Transactions of the Institute of British Geographers, New Series 21:526.Google Scholar
PHILLIPS, O. L., MALHI, Y., HIGUCHI, N., LAURENCE, W. F., NUÑEZ, P. V., VASQUEZ, R. M., LAURENCE, S. G., FERREIRA, L. V., STERN, M., BROWN, S. & GRACE, J. 1998. Changes in the carbon balance of tropical forests: evidence from long-term plots. Science 282:439442.Google Scholar
ROMOLEROUX, K., FOSTER, R., VALENCIA, R., CONDIT, R., BALSLEV, H. & LOSOS, E. 1997. Especies leñosas (dap ≥1 cm) encontradas en dos hectáreas de un bosque de la Amazonía ecuatoriana. Pp. 189215 in Valencia, R. & Balslev, H. (eds.). Estudios Sobre Diversidad y Ecología de Plantas. Pontificia Universidad Católica del Ecuador, Quito.Google Scholar
ROOSEVELT, A. C., HOUSLEY, R. A., IMAZIO, DA, SILVEIRA, M., MARANCA, S. & JONHNSON, R. 1991. Eight millennium pottery from prehistoric shell midden in the Brazilian Amazon. Science 254:16211624.Google Scholar
SCATENA, F. N., MOYA, S., ESTRADA, C. & CHINEA, J. D. 1996. The first five years in the reorganization of aboveground biomass and nutrient use following hurricane Hugo in the Bisley Experimental Watersheds, Luquillo Experimental Forest, Puerto Rico. Biotropica 28:424440.Google Scholar
STEININGER, M. 2000. Secondary forest structure and biomass following short and extended land-use in central and southern Amazonia. Journal of Tropical Ecology 16:689708.Google Scholar
TUOMISTO, H., POULSEN, A. D., RUOKOLAINEN, K., MORAN, R. C., QUINTANA, C., CELI, J. & CAÑAS, G. 2003. Linking floristic patterns with soil heterogeneity and satellite imagery in Ecuadorian Amazonia. Ecological Applications 13:352371.Google Scholar
VALENCIA, R., FOSTER, R., VILLA, G., CONDIT, R., SVENNING, C. J., HERNÁNDEZ, C., ROMOLEROUX, K., LOSOS, E., MAGAARD, E. & BALSLEV, H. 2004. Tree species distributions and local habitat variation in the Amazon: a large forest plot in eastern Ecuador. Journal of Ecology 92:214229.Google Scholar
WRIGHT, S. J. 2005. Tropical forests in a changing environment. Trends in Ecology and Evolution 20:553560.Google Scholar