Detection of Interannual Climate Variability in Secondary Forests and Crops Under Traditional and Alternative Shifting Cultivation Using Ikonos Data

HR: 1340h
AN: B43A-0135 [Abstracts]
TI: Detection of Interannual Climate Variability in Secondary Forests and Crops Under Traditional and Alternative Shifting Cultivation Using Ikonos Data
AU: Sa, T
EM: tatiana@cpatu.embrapa.br
AF: EMBRAPA Amazonia Oriental, Tv. Eneas Pinheiro s/n, Belem, PA 66095-100 Brazil
AU: * Guild, L
EM: Liane.S.Guild@nasa.gov
AF: NASA Ames Research Center, Ecosystem Science and Technology Branch, MS 242-4, Moffett Field, CA 94035 United States
AU: Carvalho, C
EM: carvalho@castanha.cpatu.embrapa.br
AF: EMBRAPA Amazonia Oriental, Tv. Eneas Pinheiro s/n, Belem, PA 66095-100 Brazil
AU: Wickel, A
EM: bwickel@uni-bonn.de
AF: University of Bonn, Center of Development Research/ZEF, Department of Ecology and Resource Management, Bonn, D-53113 Germany
AU: Brienza, S
EM: brienza@cpatu.embrapa.br
AF: EMBRAPA Amazonia Oriental, Tv. Eneas Pinheiro s/n, Belem, PA 66095-100 Brazil
AU: Kato, M
EM: skato@cpatu.embrapa.br
AF: EMBRAPA Amazonia Oriental, Tv. Eneas Pinheiro s/n, Belem, PA 66095-100 Brazil
AU: Kato, O
EM: okato@cpatu.embrapa.br
AF: EMBRAPA Amazonia Oriental, Tv. Eneas Pinheiro s/n, Belem, PA 66095-100 Brazil
AU: Leibs, C
EM: cleibs@gmail.com
AF: Aragon High School, 900 Alameda de las Pulgas, San Mateo, CA 94402 United States
AB: Regenerating forests play an important role in long-term carbon sequestration and sustainable landuse as they act as potentially important carbon and nutrient sinks during the shifting agriculture fallow period. The long-term functioning of secondary forests (capoeira) is increasingly threatened by a shortening fallow period during shifting cultivation due to demographic pressures and associated increased vulnerability to severe climatic events. Declining productivity and functioning of fallow forests of shifting cultivation combined with progressive loss of nutrients by successive burning and cropping activities has resulted in declining agricultural productivity. In addition to the effects of intense land use practices, droughts associated with El Nino events are becoming more frequent and severe in moist tropical forests and negative effects on capoeira productivity could be considerable. The principal goal of the research is to determine the extent to which capoeira and agricultural fields are susceptible to extreme climate events (drought) under contrasting landuse/clearing practices. In Igarape-A㎡ (near Belem, Para), we hypothesize that experimental alternative landuse/clearing practices (mulching) may make capoeira and crops more resilient to the effects of agricultural pressures and drought through increased biomass, soil organic matter and associated increase in soil water storage, and nutrient retention. This experimental practice (mechanized chop-and-mulch) has resulted in increased soil moisture during the cropping phase, reduced loss of nutrients and organic matter, and higher rates of secondary-forest biomass accumulation. This project aims to measure water availability and it's relation to secondary forest and crop productivity in the Brazilian Amazon. We have conducted field efforts during two dry seasons (August-December). Field data on water relations were collected during the dry season of 2001 and 2002 in capoeira and crops for both traditional slash-and-burn and alternative chop-and-mulch practices. These data will be used to compare with IKONOS data (2001 and 2002) products for the detection of moisture status differences. Current research includes comparison of IKONOS vegetation indices (NDVI and EVI) and the Tasseled Cap transformation for detection of water stress in capoeira and crops that were measured in the field.
DE: 9360 South America
DE: 1866 Soil moisture
DE: 1615 Biogeochemical processes (4805)
DE: 1640 Remote sensing
DE: 0400 Biogeosciences
SC: Biogeosciences [B]
MN: 2004 AGU Fall Meeting