advances in land cover/use changes for biogeochemical and hydrological modeling diógenes s. alves...
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Advances in Land Cover/Use Changes Advances in Land Cover/Use Changes for Biogeochemical and Hydrological for Biogeochemical and Hydrological ModelingModeling
Diógenes S. AlvesDiógenes S. Alves
Instituto Nacional de Pesquisas EspaciaisInstituto Nacional de Pesquisas Espaciais
http://www.dpi.inpe.br/dalves/Diogenes.htmlhttp://www.dpi.inpe.br/dalves/Diogenes.html
3rd LBA Conference3rd LBA Conference
Brasilia, 29 July 2004Brasilia, 29 July 2004
D. Alves, 3rd LBA ConferenceD. Alves, 3rd LBA Conference
RugendasRugendas
A tentative summary of land cover/use changes for biogeochemistry and hydrology:
1. Spatial concentration Pasture-dominated landscapes
2. Annuals in very large farms: soy beans, rice, mayse
3. Secondary vegetation decline; pasture growth4. Crop decline (small farms); pasture growth5. Cattle growing faster than pastures
Alves 2002 I.J.R.S.Alves 2002 I.J.R.S.
Spatial concentration of forest clearing:Spatial concentration of forest clearing:Landscapes increasingly pasture-dominatedLandscapes increasingly pasture-dominated
D. Alves, 3rd LBA ConferenceD. Alves, 3rd LBA Conference
Alves et al 2003 I.J.R.S.Alves et al 2003 I.J.R.S.
Deforestation, abandonment and Deforestation, abandonment and pasture-use intensification: pasture-use intensification: effects of effects of managementmanagement
D. Alves, 3rd LBA ConferenceD. Alves, 3rd LBA Conference
Distributions of cattle densities inDistributions of cattle densities inBrazilian Amazon: 1985-1995/96Brazilian Amazon: 1985-1995/96
Higher cattle densities occurred more frequently in 1995/96Higher cattle densities occurred more frequently in 1995/96
than in 1985. than in 1985. PASTURE INTENSIFICATION TRENDPASTURE INTENSIFICATION TREND
00.10.20.30.40.50.60.70.80.9
1
>=1.5 1.3-1.5
1.1-1.3
0.9-1.1
0.7-0.9
0.5-0.7
<0.5
Stocking rates (head ha-1)
Fre
quen
cy (
cum
)
1985
1995/96
D. Alves, 3rd LBA ConferenceD. Alves, 3rd LBA Conference
Alves in prep.Alves in prep.
Distributions of temporary crops inDistributions of temporary crops inBrazilian Amazon: 1985-1995/96Brazilian Amazon: 1985-1995/96
Crops represented larger fractions of land use in 1985 than in Crops represented larger fractions of land use in 1985 than in
1995/96 – 1995/96 – (almost) BASIN-WIDE RANCHING TREND(almost) BASIN-WIDE RANCHING TREND
D. Alves, 3rd LBA ConferenceD. Alves, 3rd LBA Conference
00.10.20.30.40.50.60.70.80.9
1
<3 3-6 6-9 9-12 12-15 15-18 >=18
Temp crops (% use)
Fre
quen
cy (
cum
)
1985
1995
Alves in prep.Alves in prep.
Alves in prep.Alves in prep.
Alves em prep.Alves em prep.
Crops inside and outside the “soy bean” pocketsCrops inside and outside the “soy bean” pockets
0102030405060708090
100
> 30% 25-30%
20-25%
15-20%
10-15%
5-10% < 5%
Crop area as a fraction of total area in agricultural use
Fra
ctio
n o
f to
tal c
rop
ar
ea (
%cu
m)
85 soy 95 soy
0102030405060708090
100
> 30% 25-30%
20-25%
15-20%
10-15%
5-10% < 5%
Crop area as a fraction of total area in agricultural use
Fra
ctio
n o
f to
tal c
rop
are
a (%
cum
)
85 n soy 95 n soy
0102030405060708090
100
< 100ha 100-200ha 200-500ha 500-1k ha > 1k ha
Size category
Fra
ctio
n o
f 19
95 c
rop
are
a in
siz
e ca
teg
ory
(%
cum
)
95 soy 95 no soy
Soy beans represent largeSoy beans represent largefractions of total land usefractions of total land useSoy bean implies land rotation Soy bean implies land rotation (young fallow or grass ?)(young fallow or grass ?)
D. Alves, 3rd LBA ConferenceD. Alves, 3rd LBA Conference
SummarySummary
D. Alves, 3rd LBA ConferenceD. Alves, 3rd LBA Conference
What follows from pasture use What follows from pasture use intensification ?intensification ?
– What mid/large-scale biogeochemical and What mid/large-scale biogeochemical and hydrological changes follow past use hydrological changes follow past use intensification ?intensification ?
– What will be the life cycle of pastures ?What will be the life cycle of pastures ?
– How pasture use intensification is being How pasture use intensification is being achieved ? (effects on biogeochemistry, run achieved ? (effects on biogeochemistry, run off ...)off ...)
– What are the pathways outside OLD/NEW What are the pathways outside OLD/NEW areas ?areas ?
– What are landscape configurations (forest, What are landscape configurations (forest, crops, sec vegetation, grasses) in soy-bean crops, sec vegetation, grasses) in soy-bean producing areas ?producing areas ?
– Biogeochemical and hydrological changes Biogeochemical and hydrological changes following agriculture intensification ?following agriculture intensification ?
Thank you ...Thank you ...