Landuse transitions and their implications for...
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Land use transitions and their implications for ecosystem services LI Xiubin (CAS - IGSNRR) International Conference on Science and Technology for Sustainability 2011: Building up regional to global sustainability-Asia vision. 14-16 September 2011, Kyoto
Transcript of Landuse transitions and their implications for...
国家自然科学基金委员会地球科学部
中国水利水电科学研究院
Land use transitions and their implications for ecosystem services
LI Xiubin (CAS - IGSNRR)
International Conference on Science and Technology for Sustainability 2011: Building up regional to global sustainability-Asia vision. 14-16 September 2011, Kyoto
Trilemma in land use policy
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Food security
Ecological security
Urban development
PolicyTrade-off
Land for nature = Total land area – (Agricultural area + Settlements)
Land use Transition or Forest Transition (FT) ——A. Mather
The passage, in modern times, from net deforestation to net
reforestation in a defined area, usually a country.
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France
Forest transition started from 1800, e.g:
Denmark——early 19 century；France——mid 19 century；Portugual——1870s；
Northeast US——early 20 century；
Japan——probably18 century
Forest transition in emerging economies
Some developing countries have recently achieved a land use transition with a simultaneous increase in food production and forest cover.
4Data sources: Lambin and Meyfroidt PNAS | March 1, 2011 | vol. 108 | no. 9 | 3469
Others include:
India, Bhutan, Chile,Western Honduras, Puerto Rico, Southern and Central Mexico
Forest transition in Asia
Asia ushered its forest transition in the turn of the century thanks to the slowdown of deforestation in southeast Asia.
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Data sources: FAO/FRA2010
560
565
570
575
580
585
590
595
600
1990 2000 2005 2010
Area/
million
ha
Asia
270280290300310320330
1990 2000 2005 2010
Area/
million
ha
South and South-east Asia
170
190
210
230
250
270
1990 2000 2005 2010
Area/
million
ha
East Asia
40
41
42
43
44
1990 2000 2005 2010
Area/
million
ha
Western and Central Asia
Driving forces: Two paths of FT
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Barbier, E. B. et al, Land Use Policy 27 (2010) 98–107Rudel, et al. 2005
Economic development path
Forestscarcity path
The economic development path: farmland marginalization
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Intensification
of fertile landsCrowding-out effect
Farmland
marginalization or
abandonmentagricultural
labor force
drain out
Technology
Urbanization
Macro-scope
Reasons for farmland marginalization/abandonment:
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Rise of labor wage in
urban sectors
Rise of opportunity labor
cost in rural sectors
Urbanization and
slowing down pop.
growth
Decline in farmland
rent
Marginalization of
remote sloping or
arid farmland
Micro-scope
Farmland abandonment
Cramer and Hobbs (Ed.), 2007, Old Fields: Dynamics and Restoration of Abandoned Farmland
Forest and farmland transitions in China
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70
80
90
100
110
120
130
140
150
1955
1960
1965
1970
1975
1980
1985
1990
1995
2000
2005
2008
Cu
ltiv
ated
lan
d /
mill
ion
ha
Forest area Cultivated land
5000.00
7000.00
9000.00
11000.00
13000.00
15000.00
17000.00
19000.00
1973-1976
1977-1981
1984-1988
1989-1993
1994-1998
1999-2003
2004-2008
Area/
ten th
ou
sand
ha
China ushered its forest and farmland transitions in the 1980s.
The rising trend of ‘floating’ labor ‘s wage in recent years
蔡昉：农民工实际工资增长率，2004-2007年一直保持在7%以上，金融危机的2008年达到19.6%（该值在2002年之前几乎没有增长，2002年为2-3%，2003为5-6%），说明刘易斯拐点已经到来。
蔡舫，南方周末，2010-3-24
Slowing down population growth
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Replacement level
One-child policy
Low fertility trap
China became a very low fertility society in 1990
Labor force in China will reach its peak soon
Proportion of laborTotal dependency ratio
中国劳动力人口将在2015年迎来拐点
——Renmin University of China, 2010(http://ier.ruc.edu.cn/xszy.asp)
Rapid urbanization (as projected with Northam’s S-curve)
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0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0 19
50
1955
1960
1965
1970
1975
1980
1985
1990
1995
2000
2005
2010
2015
2020
2025
2030
2035
2040
2045
2050
2055
2060
2065
2070
2075
2080
Accelerating stage
Data sources：UNDESA，World Urbanization Prospects: The 2007 Revision
Now 49.68%
2050：73.23%
Changes in forest carbon stock
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——Fang et al. 2001; Guo et al. 2010; Li et al. 2011
上
游
地
区
上
游
地
区
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
1973-1976 1977-1981 1984-1988 1989-1993 1994-1998 1999-2003 2004-2008
Car
bo
n s
tock
/Tg
Changes in forest cover in major soil erosion area :
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——Forest inventory data
南方红黄壤丘陵区
近20年提高迅速
南方红黄壤丘陵区 黄河中上游地区 长江上游地区
上
游
地
区
上
游
地
区
0
5
10
15
20
25
30
35
40
45
5019
77-1
981
1984
-198
8
1989
-199
3
1994
-199
8
1999
-200
3
2004
-200
8
1977
-19
81
1984
-19
88
1989
-199
3
1994
-199
8
1999
-200
3
2004
-200
8
1977
-19
81
1984
-19
88
1989
-199
3
1994
-199
8
1999
-200
3
2004
-200
8
Wild lives is expanding their territory ——Wild boar disaster
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2000~2010年浙江省野猪数量从29,000只增加到150,000只。10年间增长了4倍。
Wild pig invasion of the West Lake scenic area
——Nanfang Weekend, Sept.22, 2010
Conclusions and implications
National or continent-wide FT provide a valuable perspective
for ecologically sustainable development;
Major driving forces are unbanisation and cropland
marginalisation;
But the possibility of a global FT is still questionable.
Shrinkage of grain farming
Low-end marginalization
High-end marginalization
