Characterization and Performance of Amazonian Dark Earths –
Opportunities for Future Soil Management
Johannes LehmannJohannes LehmannDepartment of Crop and Soil Sciences, Cornell UniversityDepartment of Crop and Soil Sciences, Cornell University
Upland soils in the Amazon Basin
Constraints:Constraints:Rapid nutrient leaching andRapid nutrient leaching andmineralizationmineralization of organic matterof organic matter
PP--fixation to Fefixation to Fe--, Al, Al--oxidesoxides
Low total K, Ca, Mg contentsLow total K, Ca, Mg contents
Al toxicity possible through low pHAl toxicity possible through low pH
Extremely fertile soils in the midst of infertile Oxisols
Oxisol
© G
lase
r
“Terra Preta de Indio”
Amazonian Dark Earths – soil fertility
High soil fertilityHigh soil fertility
© J.
Maj
or, 2
003
“Terra Preta de Indio”Oxisol
Amazonian Dark Earths – highly valued resource
© W
oods
FarmingOrnamentals
Amazonian Dark Earths– soil fertility
High organic matter contents (to 150 mg C gHigh organic matter contents (to 150 mg C g--11))High nutrient availability (e.g., P (>300 mg kgHigh nutrient availability (e.g., P (>300 mg kg--
11) and Ca) ) and Ca) HighHigh cationcation exchange capacity (CEC)exchange capacity (CEC)
Amazonian Dark Earths– nutrient contents
Cluster A
Cluster B
Terra PretaNon-anthropogenic soil
Cluster A
Cluster B
Terra PretaNon-anthropogenic soil
Cluster A
Cluster B
Terra PretaNon-anthropogenic soil
Cluster A
Cluster B
ADE soilNon - anthropogenic soil
Cluster A
Cluster B
Terra PretaNon-anthropogenic soil
Cluster A
Cluster B
Terra PretaNon-anthropogenic soil
Cluster A
Cluster B
Terra PretaNon-anthropogenic soil
Cluster A
Cluster B
ADE soilNon - anthropogenic soil
ADE soil Non-ADE soil
Madari et al., 2003, in: Amazonian Dark Earths (Lehmann, Kern, Glaser, Woods, eds.) Kluwer Ac, pp. 407-432.
Amazonian Dark Earths– nutrient contents
Greater increase Greater increase in available in available nutrients than nutrients than total nutrientstotal nutrients
Diff
eren
ce fr
om a
djac
ent F
erra
lsol
[log
%]
100
1000
10000
100000Total nutrientsAvailable nutrients
N[1]
N N[2]
P P P P P[2]
P P[3]
P[4]
P P P[5]
S S S[1]
Ca Ca[2]
nd nd nd
Lehmann et al., 2003, in: Amazonian Dark Earths (Lehmann, Kern, Glaser, Woods, eds.) Kluwer Ac, pp. 105-124.
Amazonian Dark Earths– nutrient contents
Diff
eren
ce fr
om a
djac
ent F
erra
lsol
[%]
0
100
200
300
400
500
600
700
Total nutrientsAvailable nutrients
K K[3]
Mg Mg[3]
Fe Fe[3]
Zn Zn[3]
Mn Mn[3]
Cu Cu[3]
ndnd
Lehmann et al., 2003, in: Amazonian Dark Earths (Lehmann, Kern, Glaser, Woods, eds.) Kluwer Ac, pp. 105-124.
Amazonian Dark Earths– N availability
Incubation [days]0 20 40 60 80 100 120 140 160C
umul
ativ
e N
min
eral
izat
ion
[mg
N g
-1 N
]
0
20
40
60
80
100sandy Amazonian Dark Earthsandy Ferralsolclayey Amazonian Dark Earthclayey Ferralsol
14.7
15.4
15.3
10.3
C/N ratioLow N availabilityLow N availability
Glaser, 1999, in Lehmann et al., 2003, in: Amazonian Dark Earths (Lehmann, Kern, Glaser, Woods, eds.) KluwerAc, pp. 105-124.
Amazonian Dark Earths– Biological N2Fixation (Central Amazonia)
Low N availabilityLow N availabilityHigh P, Ca, and micronutrient availabilityHigh P, Ca, and micronutrient availability
Parameter ADE Ferralsol
Leguminosae (% of all trees) 14 4
Foliar N conc. (mg g-1) 26 29
Foliar δ15N (‰) 1.75 3.59
N and N isotopes from potentially N2-fixing trees Gehring, 2003, PhD thesis, annex 9.
Amazonian Dark Earths– nutrient leaching
Days10 20 30 40 50
Cal
cium
cum
ulat
ive
leac
hing
[kg
ha-1
]
0
2
4
6
8
10
12
Ferralsol
Terra Preta
Ca15
33
Available Ca:(Mehlich-3)
Lehmann et al., 2003, Plant and Soil 249: 343-357
High nutrient High nutrient availability at availability at very low very low leaching!leaching!
Amazonian Dark Earths–production potential
AmazonianDark Earths
LRN*LRN
LRNRPE*
LRN NA RULRN
LRNLRN RU
LRN NA RULRN
LRNLRN
LRN
Yie
ld [g
pot
-1]
020406080
100120140160180200
0 0 0
Transitional Soils
Ferralsols
a ab
b
German, 2002, in Lehmann et al., 2003, in: Amazonian Dark Earths (Lehmann, Kern, Glaser, Woods, eds.) Kluwer Ac, pp. 105-124.
Higher maize Higher maize yields in ADE yields in ADE than adjacent than adjacent soils soils -- but large but large variabilityvariability
(N=3)
Crop yields are higher on Amazonian Dark Earths than adjacent soils.
Amazonian Dark Earths–production potential
Crop Location ADE Ferralsol--------------[Mg ha-1]------------
Rice Apui 1.9-3.4 1.5-1.8
Beans Apui 0.1-1.9 0.3-0.8
Corn Apui 2.2-4.7 3.5
Martins, unpubl., in Lehmann et al., 2003, in: Amazonian Dark Earths (Lehmann, Kern, Glaser, Woods, eds.) Kluwer Ac, pp. 105-124.
Opportunities for Science
Life in preLife in pre--ColumbianColumbian AmazoniaAmazonia
Basic biogeochemistry of soilsBasic biogeochemistry of soils
Soil managementSoil management
Amazonian Dark Earths– Black CarbonLarge proportion of Black-Carbon in soil organic matter of ADE
0
20
40
60
80
100
0 100 200 300
Black carbon [g kg-1 C]
Terra Preta
Ferralsol
Glaser et al., 2001, Naturwissenschaften 88, 37-41
Dep
th [
cm]
Amazonian Dark Earths– Black Carbon
What is Black Carbon?What is Black Carbon?
What does Black Carbon?What does Black Carbon?
Amazonian Dark Earths–Black Carbon
Schmidt and Noack, 2000, Global Biogeochemical Cycles 14, 777-793
From charcoal to graphite
Amazonian Dark Earths– Black Carbon
Large portion of Carbon and Black Carbon in “light organic matter” fractions of Terra PretaFraction Density Terra Preta Ferralsol
[g cm-3] --------------------[%]--------------------
CarbonLight <2 35 28Medium 2-2.4 36 25Heavy >2.4 29 48
Black carbonLight <2 72 32Medium 2-2.4 12 22Heavy >2.4 16 46
(N=5) Glaser et al., 2000, Org Geochem 31, 669-678
Functions of biomass-derived Black Carbon (=charcoal)
Improving nutrient retention?Improving nutrient retention?Increasing nutrient availability and Increasing nutrient availability and
crop yields?crop yields?Enhancing carbon sequestration?Enhancing carbon sequestration?
…as in ADE?
Black Carbon Management Systems
…evidence so far:
Better nutrient retention.Better nutrient retention.Greater nutrient availability and crop Greater nutrient availability and crop
yields at high application rates or with yields at high application rates or with additional fertilization.additional fertilization.
Reduced greenhouse gas emissions.Reduced greenhouse gas emissions.
Black Carbon Management Systems
Black carbon additions [Mg C ha-1]0 50 100 150 200Pl
ant b
iom
ass
prod
uctio
n [%
of c
ontro
l]
0
100
200
300
400
500
Lehmann and Rondon, submitted
Black Carbon Management Systems
23
45
67
0 50 100Charcoal rate (g/kg soil)
(g/p
ot)
Optimum response curve
Biomass production of common beans (Phaseolus vulgaris L.) (N=4)Rondon et al., in prep.
Nitr
ogen
sou
rce
(mg
pot-1
)
0
20
40
60
80
100
120
NdfSNdfA
Charcoal applied (g kg-1)
0 30 60 90
Nitr
ogen
sou
rce
(%)
0
20
40
60
80
100
c b aab
c ab
bc
a
a ab
a
ab cbc
Black Carbon Management Systems – BNF
BNF of common beans (Phaseolus vulgaris L.)determined by isotope dilution (N=4)
Rondon et al., in prep.
Black Carbon Management Systems
Multiple environmental and agricultural benefits
Sustainability of soil amelioration
Accountability of carbon sequestration
Combination with existing land management systems (e.g. slash-and-burn) as well as charcoal and energy production systems