Improving fertilizer use efficiency through management practices
Improving fertilizer use efficiency through management practices – China experience
Outline ¾ Importance and problem of fertilizer production and consumption in China
¾ Principles, dissemination and performance of fertilizer best management practices (FBMPs)
Zhang F S, Fan M S, Zhang W F Department of Plant Nutrition China Agricultural University Beijing, 100094, P.R.CHINA
in crop production
¾ Conclusions and perspectives
It took nearly 50 yrs to realize the dream of food sufficiency in China with massive inputs
Million ton
600
Grain demand Grain production
533
500
600
407 305
300
Consumption= production+import-export
640
470
400
200
560
214
100
60
56.8
N Fertilizer consumption （ Million tones nutrient ）
700
China consumed more than 56 million tones of NPK nutrients as inorganic fertilizer in 2006
50
P2O5
40
Total
45.0
K2 O 30.6
30 22.3 20 10.9 10 0
1961 1969 1977 1985 1993 2001 2009 2017 2025 (Data from the Statistic Bureau of China Demand was estimated by using average grain demand of 400 kg/capita/year)
1949
1956
1963
1970
1977
1984
1991
1998
2006
The trends of fertilizers consumption in China from 1949 to 2006
1
Rapid Development of Chinese Fertilizer Industry
25
70
Nutrient (Mt)
Agriculture consumption Production
60 Nutirent (Mt)
More than 60% global new fertilizer production capacity will be in China in the next five years
50 40 30
Phosphate Potash Nitrogen
20 15 10
20
5
10
0
0 1985
1989
1993
1997
2001
2005
World
2009
(Data for 1981-2006, The Statistics Bureau of China Data for 2007-2010, forecasted by industry survey-based model)
Policies stimulate a rapid expansion of the fertilizer enterprises
(World data from IFADATA, data for China from industry survey)
China
Production
Consumption
11000
Nutrient (10000t)
10000 9000 8000 7000
Developed country
6000 5000
Amount of fertilizer（0000 tones nutrient） Grain Planting area (100000 ha)
Consumption
9% of world arable land 21% of world population 35% of world fertilizer consumption
7000
65000 Fertilizer Grain Production Grain Yield Area
6000
Production
China
60000 55000
5000 50000 4000
45000
3000
40000 35000
2000 30000 1000 25000
4000 3000
0
20000 1975
2000
China
1000
Grain procduction（0000 tones） Grain Yield (100g/ha)
1981
1978
1981
1984
1987
1990
1993
1996
1999
2002
2005
Year
Trends of grain yield, production, grain area and fertilizer consumption (1975 – 2006)
0 1961
1967
1973
1979
1985
1991
1997
2003
2009
(Forecast based on the increase rate of recent five years Data from FAO website and Chinese statistics )
• From 1984 to 1994, Fertilizer consumption increased by 90%, but the grain production increased by 9%; • After 1996 no such a relationship can be demonstrated!
2
Low nutrient use efficiency (NUE) ---Low PFP 200
60
175
55
150
50
125
45
100
40
75
35
50
30
PFPN(kg grain/kg N)
Fertilizer application rate (kg/ha)
Partial factor productivity: PFPN = kg harvest product per kg N applied
y = -0.9308x + 1892.1 25
Agronomic efficiency of N fertilizer in rice Philippine
1515-18 kg grain/kg N
China (1958(1958-1963)
1515-20 kg grain/kg N
China ( 19811981-1983)
9.1 kg grain/kg N
China ( 20002000-2004)
3-5 kg grain/kg N
25
2
R = 0.8502 20
0 1980
1985
1990
1995
2000
(Modified from Cassman et al., 1996; Li, 1991)
2005
year
Substantial decrease in PFPN with increased rate of fertilization
Fertilizer Overuse and Misuse Grain yield and N rate of rice crop Country
Grain yield*
N rate
(t ha-1)
(kg ha-1)
China
6.26
~200
Japan
6.42
70
South Korea
6.79
110
*FAO, 2004
3
WheatWheat-maize rotation system （n =156, six years)
600
90 400
80 70
200
60 0
50 200
300
400
500
600
N rate (kg N/ha) 122 kg N/ha
100
400
90 80 70
200
60 50
0 0
100
200
6
3
450
2001
2002
2003
2004
2005
Decrease N application by 71%
Non-point source pollution
300 150
600
N losses (kg N/ha)
Relative yield (%)
110
Eutrophication
9
0 600 2000
300
N rate (kg N/ha)
400
0 1000
Nitrate-N (kg N/ha)
100
Grain yield (t/ha)
N losses (kg N/ha)
800
100
0
FP
Increase grain yield by 7%
N rate (kg N/ha)
112 kg N/ha
110
Relative yield (%)
FBMPs 12
2000
2001
2002
2003
2004
2005
Reduce residue nitrate-N by 62% 推荐
750
习惯
500 250
0 W-M
W-M
2000
2001 2002 2003 2004 2005
W-M
W-M
W-M
W-M
¾ Four fold increase in N inputs to estuaries since 1980 ¾ Increased N inputs contribute to eutrophication, decreased fish production, and toxic algal bloom (red tides) ¾ The occurrence of red tides increased from 10/yr in the 1960s to 300/yr now (Norse and Zhu,2004)
Fertilized to death Nature 30 October 2003, 425:894 -895
Outline ¾ Importance and problem of fertilizer production and consumption in China
¾ Principles, dissemination and performance of fertilizer best management practices (FBMPs) in crop production
“Countries such as China have no intention of reducing their use of nitrogen”, says Moldan. “In fact they are firmly committed to increasing it. ”
¾ Conclusions and perspectives
4
Principles: 1) Match application to crop requirement, apply when crop is growing fast
Timing of fertilizer application – at time of rapid crop uptake of nutrients Seems obvious – but often ignored!
N uptake intensity
Much was applied before/at planting time! V4
Sowing
V10
V6
V
N rate during 10d after transplanting (kg/ha) (%)
160
N application rates (kg/ha)
140
R6
R2
Tillering
Jiangsu Zhejiang Hunan Guangdong IRRI
120 Mid-Panicle 100 Head 80
240 200 180 200 90
70% 85% 56% 68% 0
60
Problems of farmer’s practice in winter-wheat in north China Fertilization
N uptake
Fertilization
（150kg N/ha)
（150kg N/ha)
N supply from mineral fertilizer
40
Mature Crop N uptake
20 0 0
15
30
45
60
75
90
105 120
Growing stage（day）
Problems of farmer’s practice in rice production
nutrient
water
5
N application in early stage leads to poor growth of maize (right)
Principles: 2) Take all possible sources of nutrient into consideration!
Sources of nutrients
how much nutrient in organic fertilizer! Amount of potential organic fertilizers in China
5000
Fertilizers
Soil Crop residues
Total amount(Million t)
Rain & atmospheric deposition
Farmer (even expert) never knows that
4000 3000 2000 1000
Manure
Irrigation water
Biological N fixation
2000
1998
1995
1997
1996
1994
1993
1990
1992
1989
1991
1988
1987
1986
1985
0
NPK nutrient in potential organic sources in 2000: 2869 104t N, 1510 104tP2O5, 2921 104t K2O
6
Important N source- wet and dry deposition
Large amount of nitrate accumulated in soil
大气氮沉降监测点
Wheat-maize rotation in North China Plain： Annual input (deposition): 80-90 kg N ha-1 Accounting for crop demand of 20-30%
N in 100cm
Rice-wheat along the Yangtze River Basin: Annual input (deposition + BNF): 103-127 kg N ha-1 Accounting for crop demand of 30-40%
384(n=140)
1267(n=140)
651(n=206)
280
329
121
100cm
Crop demand
N accumulation as nitrate in 0-100cm soil layer(kg/ha) in cereal, vegetable and fruit production systems in China Groundwater
Principles:
A gap in yield 25000
85.9 (104 ha)
15000
5000
National average maize yield
0
2002 2005
Record yield of summer maize in China
1987 1990 1993 1996 1999
10000
1978 1981 1984
measures into consideration!
1407.3(104 ha)
1972 1975
yield and reducing nutrient loss
Yield（kg/ha）
3) Take all possible improving
20000
YD13 (1991-2000) YD22(1997-2000)
Year
(Li, 2004; FAO; website:http://www.cornexpert.com, http://www.denghai.com/)
7
Wheat and maize potential and actual yield:
Improving NUE by increasing crop yield
Potential yield: Winter wheat: 9000-11000 kg/ha Summer maize: 11250-15000 kg/ha
FP
Improved management
Actual yield: Winter wheat: 5000 kg/ha
Yield(t/ha)
Summer maize: 6000 kg/ha
N rate (kg/ha) RE (%)
decrease
meta-analysis
increase
model estimates
18
300
889 25-30
15
Crop residues and OM amendment contributed greatly to the SOC Contribution of Agr. Management to SOC
Comparison of model estimates and meta-analysis of SOC change from1980-2000 in Chinese crop land
6
90% 80% 70% 60%
Crop residues and OM ammendment (~76%)
50% 40% 30%
Synthetic fertilizer (~22%)
20% 10%
One third of the croplands with reduced tillage (~2%)
0% 1975
1980
1985
1990 Year
1995
2000
2005
(Huang et al.,2007)
(Huang et al.,2007)
8
Principal and technology of FBMPs Total N＋Splitting in season
N management
PK management
Micronutrient management
Best management practices for highyield crop in the field
Dissemination of FBMPS
Maintenance on balance In middle and long-terms Correction when deficient
Tillage, cultivar selection, planting quality, irrigation, IPM etc.
Dissemination of FBMPS Technical manuals, leaflets and publications for teachers, officers, technicians and farmers
The distribution of 127 experiment and extension bases or stations across 12 cropping systems throughout China
Dissemination of FBMPS In cooperation with fertilizer companies focused on developing new types of fertilizer, investigation of fertilizer market, on-farm surveys of fertilizer application, and training staffs in fertilizer industry and public extension system
FP
FBMPs
9
Dissemination of FBMPs through farmers’ special association at Jianyang base in Sichuan province
Performance of FBMPs Cropping system
N saving (%) Yield increase N recovery increase (%) (%)
N loss decrease (%)
Wheat/Maize rotation
41-59
5-10
12-15
43-69
Rice
22-32
8-12
10-15
40-50
Vegetable
30-50
2-10
5-15
40-65
Cotton
20-30
5-8
10-15
10-30
Oilseed rape
10-30
5-30
8-15
-
Rice/wheat rotation
30-50
8-20
8-30
30-50
Intercropping
20-50
0-10
8-13
20-45
Tobacco
10-30
0-10
7-20
40-50
Apple
10-50
5-15
2-12
-
FBMP treatments on average have saved N by 20-40%, increase yields by 2-12%, increase N recovery rates by 1015%, and decrease N losses by 10-50%
FP
FBMPs
Shandong，2004 Saving N by 30%，Yield increase by 16%
Anqing station, Heilongjiang （05.8.28）
FBMPs
9.0t/ha
8.3t/ha
FP
10
Outline ¾ Importance and problem of fertilizer production and consumption in China
¾ Principles, dissemination and performance of fertilizer best management practices (FBMPs)
Technologically, FBMPs is a feasible solution to tackle or alleviate the problems of fertilizer overuse and misuse in cropping systems.
in crop production
¾ Conclusions and perspectives
Action of The Ministry of Agriculture National Program for Soil Testing and Fertilizer Recommendation
11.7 million tons fertilizer can be saved by the above actions
Soil Testing
Fertilizer production
Fertilizer application
Increase in
65 +22%
60 +13%
55 +5.6%
Farmers’ practice (7.5kg/kg)
Soil testing +23% action (12.5 kg/kg) +15%
+8%
50
Intern. BMPs (20 kg/kg)
45 Fertilizer distribution
Field experiment
+39%
+2.1%
Fertilizer prescription
Aims：
Fertilizer demand（Mt）
70 200 Million RMB￥covers 200 counties in 2005, 500 Million RMB￥covers 600 counties in 2006, and 900 Million RMB￥covers 1200 counties in 2007
Fertilizer use efficiency: 3-5% ; Crop yield ：5%; Recycling rate of organics: 40-50%;
2005 2010 2020 2030 Fertilizer demand as affected by different efficiencies Note: Increased demand of cash crops is not included grain demand is 520 Mt, 580 Mt and 640 Mt in 2010,2020 and 2030 Efficiencies (AE) in three practices are 7.5kg/kg,12.5kg/kg and 20kg/kg
(W Zhang Unpublished)
11
What are the determinants of the use of fertilizers by farmers?
Politically ¾High input and high output policy leads to higher use ¾Modern varieties make it possible to apply more fertilizer ¾Current extension system leads to higher use
Perspectives Change policies : both in agriculture and fertilizer industry –Develop and extend fertilizer saving technologies –Train farmers –Reform current public agricultural extension system
–Make new technology policy: •Encourage the development of fertilizer-sensitive technologies
Acknowledgments 948 of MOA No. 2003-Z53 FAI and IFA
Thanks for your attention !
12
Outline ¾ Importance and problem of fertilizer production and consumption in China
¾ Principles, dissemination and performance of fertilizer best management practices (FBMPs)
Zhang F S, Fan M S, Zhang W F Department of Plant Nutrition China Agricultural University Beijing, 100094, P.R.CHINA
in crop production
¾ Conclusions and perspectives
It took nearly 50 yrs to realize the dream of food sufficiency in China with massive inputs
Million ton
600
Grain demand Grain production
533
500
600
407 305
300
Consumption= production+import-export
640
470
400
200
560
214
100
60
56.8
N Fertilizer consumption （ Million tones nutrient ）
700
China consumed more than 56 million tones of NPK nutrients as inorganic fertilizer in 2006
50
P2O5
40
Total
45.0
K2 O 30.6
30 22.3 20 10.9 10 0
1961 1969 1977 1985 1993 2001 2009 2017 2025 (Data from the Statistic Bureau of China Demand was estimated by using average grain demand of 400 kg/capita/year)
1949
1956
1963
1970
1977
1984
1991
1998
2006
The trends of fertilizers consumption in China from 1949 to 2006
1
Rapid Development of Chinese Fertilizer Industry
25
70
Nutrient (Mt)
Agriculture consumption Production
60 Nutirent (Mt)
More than 60% global new fertilizer production capacity will be in China in the next five years
50 40 30
Phosphate Potash Nitrogen
20 15 10
20
5
10
0
0 1985
1989
1993
1997
2001
2005
World
2009
(Data for 1981-2006, The Statistics Bureau of China Data for 2007-2010, forecasted by industry survey-based model)
Policies stimulate a rapid expansion of the fertilizer enterprises
(World data from IFADATA, data for China from industry survey)
China
Production
Consumption
11000
Nutrient (10000t)
10000 9000 8000 7000
Developed country
6000 5000
Amount of fertilizer（0000 tones nutrient） Grain Planting area (100000 ha)
Consumption
9% of world arable land 21% of world population 35% of world fertilizer consumption
7000
65000 Fertilizer Grain Production Grain Yield Area
6000
Production
China
60000 55000
5000 50000 4000
45000
3000
40000 35000
2000 30000 1000 25000
4000 3000
0
20000 1975
2000
China
1000
Grain procduction（0000 tones） Grain Yield (100g/ha)
1981
1978
1981
1984
1987
1990
1993
1996
1999
2002
2005
Year
Trends of grain yield, production, grain area and fertilizer consumption (1975 – 2006)
0 1961
1967
1973
1979
1985
1991
1997
2003
2009
(Forecast based on the increase rate of recent five years Data from FAO website and Chinese statistics )
• From 1984 to 1994, Fertilizer consumption increased by 90%, but the grain production increased by 9%; • After 1996 no such a relationship can be demonstrated!
2
Low nutrient use efficiency (NUE) ---Low PFP 200
60
175
55
150
50
125
45
100
40
75
35
50
30
PFPN(kg grain/kg N)
Fertilizer application rate (kg/ha)
Partial factor productivity: PFPN = kg harvest product per kg N applied
y = -0.9308x + 1892.1 25
Agronomic efficiency of N fertilizer in rice Philippine
1515-18 kg grain/kg N
China (1958(1958-1963)
1515-20 kg grain/kg N
China ( 19811981-1983)
9.1 kg grain/kg N
China ( 20002000-2004)
3-5 kg grain/kg N
25
2
R = 0.8502 20
0 1980
1985
1990
1995
2000
(Modified from Cassman et al., 1996; Li, 1991)
2005
year
Substantial decrease in PFPN with increased rate of fertilization
Fertilizer Overuse and Misuse Grain yield and N rate of rice crop Country
Grain yield*
N rate
(t ha-1)
(kg ha-1)
China
6.26
~200
Japan
6.42
70
South Korea
6.79
110
*FAO, 2004
3
WheatWheat-maize rotation system （n =156, six years)
600
90 400
80 70
200
60 0
50 200
300
400
500
600
N rate (kg N/ha) 122 kg N/ha
100
400
90 80 70
200
60 50
0 0
100
200
6
3
450
2001
2002
2003
2004
2005
Decrease N application by 71%
Non-point source pollution
300 150
600
N losses (kg N/ha)
Relative yield (%)
110
Eutrophication
9
0 600 2000
300
N rate (kg N/ha)
400
0 1000
Nitrate-N (kg N/ha)
100
Grain yield (t/ha)
N losses (kg N/ha)
800
100
0
FP
Increase grain yield by 7%
N rate (kg N/ha)
112 kg N/ha
110
Relative yield (%)
FBMPs 12
2000
2001
2002
2003
2004
2005
Reduce residue nitrate-N by 62% 推荐
750
习惯
500 250
0 W-M
W-M
2000
2001 2002 2003 2004 2005
W-M
W-M
W-M
W-M
¾ Four fold increase in N inputs to estuaries since 1980 ¾ Increased N inputs contribute to eutrophication, decreased fish production, and toxic algal bloom (red tides) ¾ The occurrence of red tides increased from 10/yr in the 1960s to 300/yr now (Norse and Zhu,2004)
Fertilized to death Nature 30 October 2003, 425:894 -895
Outline ¾ Importance and problem of fertilizer production and consumption in China
¾ Principles, dissemination and performance of fertilizer best management practices (FBMPs) in crop production
“Countries such as China have no intention of reducing their use of nitrogen”, says Moldan. “In fact they are firmly committed to increasing it. ”
¾ Conclusions and perspectives
4
Principles: 1) Match application to crop requirement, apply when crop is growing fast
Timing of fertilizer application – at time of rapid crop uptake of nutrients Seems obvious – but often ignored!
N uptake intensity
Much was applied before/at planting time! V4
Sowing
V10
V6
V
N rate during 10d after transplanting (kg/ha) (%)
160
N application rates (kg/ha)
140
R6
R2
Tillering
Jiangsu Zhejiang Hunan Guangdong IRRI
120 Mid-Panicle 100 Head 80
240 200 180 200 90
70% 85% 56% 68% 0
60
Problems of farmer’s practice in winter-wheat in north China Fertilization
N uptake
Fertilization
（150kg N/ha)
（150kg N/ha)
N supply from mineral fertilizer
40
Mature Crop N uptake
20 0 0
15
30
45
60
75
90
105 120
Growing stage（day）
Problems of farmer’s practice in rice production
nutrient
water
5
N application in early stage leads to poor growth of maize (right)
Principles: 2) Take all possible sources of nutrient into consideration!
Sources of nutrients
how much nutrient in organic fertilizer! Amount of potential organic fertilizers in China
5000
Fertilizers
Soil Crop residues
Total amount(Million t)
Rain & atmospheric deposition
Farmer (even expert) never knows that
4000 3000 2000 1000
Manure
Irrigation water
Biological N fixation
2000
1998
1995
1997
1996
1994
1993
1990
1992
1989
1991
1988
1987
1986
1985
0
NPK nutrient in potential organic sources in 2000: 2869 104t N, 1510 104tP2O5, 2921 104t K2O
6
Important N source- wet and dry deposition
Large amount of nitrate accumulated in soil
大气氮沉降监测点
Wheat-maize rotation in North China Plain： Annual input (deposition): 80-90 kg N ha-1 Accounting for crop demand of 20-30%
N in 100cm
Rice-wheat along the Yangtze River Basin: Annual input (deposition + BNF): 103-127 kg N ha-1 Accounting for crop demand of 30-40%
384(n=140)
1267(n=140)
651(n=206)
280
329
121
100cm
Crop demand
N accumulation as nitrate in 0-100cm soil layer(kg/ha) in cereal, vegetable and fruit production systems in China Groundwater
Principles:
A gap in yield 25000
85.9 (104 ha)
15000
5000
National average maize yield
0
2002 2005
Record yield of summer maize in China
1987 1990 1993 1996 1999
10000
1978 1981 1984
measures into consideration!
1407.3(104 ha)
1972 1975
yield and reducing nutrient loss
Yield（kg/ha）
3) Take all possible improving
20000
YD13 (1991-2000) YD22(1997-2000)
Year
(Li, 2004; FAO; website:http://www.cornexpert.com, http://www.denghai.com/)
7
Wheat and maize potential and actual yield:
Improving NUE by increasing crop yield
Potential yield: Winter wheat: 9000-11000 kg/ha Summer maize: 11250-15000 kg/ha
FP
Improved management
Actual yield: Winter wheat: 5000 kg/ha
Yield(t/ha)
Summer maize: 6000 kg/ha
N rate (kg/ha) RE (%)
decrease
meta-analysis
increase
model estimates
18
300
889 25-30
15
Crop residues and OM amendment contributed greatly to the SOC Contribution of Agr. Management to SOC
Comparison of model estimates and meta-analysis of SOC change from1980-2000 in Chinese crop land
6
90% 80% 70% 60%
Crop residues and OM ammendment (~76%)
50% 40% 30%
Synthetic fertilizer (~22%)
20% 10%
One third of the croplands with reduced tillage (~2%)
0% 1975
1980
1985
1990 Year
1995
2000
2005
(Huang et al.,2007)
(Huang et al.,2007)
8
Principal and technology of FBMPs Total N＋Splitting in season
N management
PK management
Micronutrient management
Best management practices for highyield crop in the field
Dissemination of FBMPS
Maintenance on balance In middle and long-terms Correction when deficient
Tillage, cultivar selection, planting quality, irrigation, IPM etc.
Dissemination of FBMPS Technical manuals, leaflets and publications for teachers, officers, technicians and farmers
The distribution of 127 experiment and extension bases or stations across 12 cropping systems throughout China
Dissemination of FBMPS In cooperation with fertilizer companies focused on developing new types of fertilizer, investigation of fertilizer market, on-farm surveys of fertilizer application, and training staffs in fertilizer industry and public extension system
FP
FBMPs
9
Dissemination of FBMPs through farmers’ special association at Jianyang base in Sichuan province
Performance of FBMPs Cropping system
N saving (%) Yield increase N recovery increase (%) (%)
N loss decrease (%)
Wheat/Maize rotation
41-59
5-10
12-15
43-69
Rice
22-32
8-12
10-15
40-50
Vegetable
30-50
2-10
5-15
40-65
Cotton
20-30
5-8
10-15
10-30
Oilseed rape
10-30
5-30
8-15
-
Rice/wheat rotation
30-50
8-20
8-30
30-50
Intercropping
20-50
0-10
8-13
20-45
Tobacco
10-30
0-10
7-20
40-50
Apple
10-50
5-15
2-12
-
FBMP treatments on average have saved N by 20-40%, increase yields by 2-12%, increase N recovery rates by 1015%, and decrease N losses by 10-50%
FP
FBMPs
Shandong，2004 Saving N by 30%，Yield increase by 16%
Anqing station, Heilongjiang （05.8.28）
FBMPs
9.0t/ha
8.3t/ha
FP
10
Outline ¾ Importance and problem of fertilizer production and consumption in China
¾ Principles, dissemination and performance of fertilizer best management practices (FBMPs)
Technologically, FBMPs is a feasible solution to tackle or alleviate the problems of fertilizer overuse and misuse in cropping systems.
in crop production
¾ Conclusions and perspectives
Action of The Ministry of Agriculture National Program for Soil Testing and Fertilizer Recommendation
11.7 million tons fertilizer can be saved by the above actions
Soil Testing
Fertilizer production
Fertilizer application
Increase in
65 +22%
60 +13%
55 +5.6%
Farmers’ practice (7.5kg/kg)
Soil testing +23% action (12.5 kg/kg) +15%
+8%
50
Intern. BMPs (20 kg/kg)
45 Fertilizer distribution
Field experiment
+39%
+2.1%
Fertilizer prescription
Aims：
Fertilizer demand（Mt）
70 200 Million RMB￥covers 200 counties in 2005, 500 Million RMB￥covers 600 counties in 2006, and 900 Million RMB￥covers 1200 counties in 2007
Fertilizer use efficiency: 3-5% ; Crop yield ：5%; Recycling rate of organics: 40-50%;
2005 2010 2020 2030 Fertilizer demand as affected by different efficiencies Note: Increased demand of cash crops is not included grain demand is 520 Mt, 580 Mt and 640 Mt in 2010,2020 and 2030 Efficiencies (AE) in three practices are 7.5kg/kg,12.5kg/kg and 20kg/kg
(W Zhang Unpublished)
11
What are the determinants of the use of fertilizers by farmers?
Politically ¾High input and high output policy leads to higher use ¾Modern varieties make it possible to apply more fertilizer ¾Current extension system leads to higher use
Perspectives Change policies : both in agriculture and fertilizer industry –Develop and extend fertilizer saving technologies –Train farmers –Reform current public agricultural extension system
–Make new technology policy: •Encourage the development of fertilizer-sensitive technologies
Acknowledgments 948 of MOA No. 2003-Z53 FAI and IFA
Thanks for your attention !
12
