Y= 5.42 +0.52X (p
1
0 5 10 15 20 25 0 5 10 15 20 25 Y=5.42+0.52X (p<0.01) 0 1 10 4 2 10 4 3 10 4 4 10 4 5 10 4 1990 Mg N 2 O-N 25% cut 0 1 10 5 2 10 5 3 10 5 0 5 10 7 1 10 8 1.5 10 8 TN-Real TN-STD y = 4030 + 0.000867x R= 0.522 (p<0.01) y = 5100 + 0.000592x R= 0.343 0 5000 1 10 4 1.5 10 4 0 5 10 7 1 10 8 TP-Real TP-STD y = 265 + 6.09e-5x R= 0.482 (p<0.01) y = 259 + 3.72e-5x R= 0.337 (p<0.01) P-load potential N-load potential P in river water (Mg) N in river water (Mg) Reduce to STD condition % of wells excess STD Potential of N leaching (ppm) A C B D 140-19: Evaluation of Japanese Agricultural N and P Management by Integrated Environmental Impact Indicator in 1990 and 2005. S. Mishima and K. Kohyama Nat. Ins. Agro-Env. Sci. Jpn ctor EmissionFa Nflows Oemission N piration Evapotrans n ecipitatio SurplusN leaching N N AvairableP N SurplusP Erosion load N P 2 Pr _ )] , , ( [ _ , 0 400km 1990 (Index) 40 30 20 10 0 400km 2005 (Index) 40 30 20 10 0 400km 2005/1990 (Ratio) 1.6 1.4 1.2 1.0 0.8 IEIin 1990 IEI in 2005 Relative change of IEI B D A C Fig.2 IEI distribution and its change and composition Fig.1 Present state and emission target Agricultural nitrogen (N) and phosphorus (P) use sometimes cause various negative environmental impacts. We set negative impacts as i) N and P load potential to surface water by erosion, ii) risk of ground water pollution by nitrate, and iii) contribution to global warming by nitrous oxide (N 2 O) emission, then estimate each negative impacts (Mishima et al. 2009, Mishima and Kohyama in review a,b). We found out that higher/lower negative impacts is not always caused by higher/lower N and P use or surplus in prefectural basis in Japan. To evaluate total negative impact in regional basis, building up integrated single indicator for environmental impact (IEI) would be necessary. For this purpose, we applied distance to target (DtT) method. In this poster, we indicated distribution of IEI and evaluated cause of regional higher IEI in Japan. Introduction Present state P and N load (P and N indicator), N leaching potential and N 2 O emission was calculated by the formulas listed below. P and N indicator summarized watershed scales were significantly correlated with amount of P and N flow at the water quality monitoring points of the watersheds (Fig 1. A, B, blue dots). N leaching potential in prefectures significantly correlated with % of observation wells that excess water quality standard in the prefecture (Fig 1. C). N 2 O-N emission was estimated to be 48GgN in 1990 (Fig. 1. D) Set the target, weighting each impacts and integration The targets were set as i)2ppm N and 0.1ppm P in river water as tentative target, ii)5.42ppm N that no well will expected to be excess water quality standard (10ppm N) and iii) cut 25% of N 2 O against 1990 by policy aim in each prefecture. Regression coefficients when river water P and N concentration is standardized as above (STD) was smaller than when real river water P and N concentration is set as 61% for P and 68% for N (Fig 1 A, B: purple dots). Weighting factors are 1.6 for P indicator (inversed value of 61%), 1.5 for N indicator (same as P), present potential of N leaching divided in each prefecture by 5.42 on risk of ground water pollution, and 1.3 (inversed value of 75%) for N 2 O emission in each prefecture. Integration as IEI was done in the below formula. Value National or in Value Weight IEI _ 2005 1990 _ _ Method IEI is higher in central Japan in both year (Fig 2 A,B). This trend is not same as N and P surplus. Numbers prefectures increased IEI was larger than reduced (Fig 2 C), although N and P surplus was generally reduced in 2005 than 1990 (Mishima et al. 2009, 2010, submitted a). Composition of IEI is indicated in Fig. 2D. Prefecture where IEI is mainly consisted with risk ground water pollution and N 2 O emission had is basically low IEI value and if prefectures where IEI contains high P and N load potential to river water indicate high IEI. Therefore, increase of IEI might be caused by increase of soil available N and P in 2005 than 1990 in prefectures. Results and discussions 1) High N and P surplus is not always caused high IEI. The other environmental conditions such as erosion potential and precipitation 2) Weight of P and N load potential might be important than risk of ground water pollution and N2O emission and are affected by soil available N and P. Conclusion S. Mishima, A. Endo, K. Kohyama (2009) Recent trend in residual nitrogen on national and regional scales in Japan and its relation with groundwater quality, NUTRIENT CYCLING IN AGROECOSYSTEMS, 83(1), 1-11 S. Mishima, A. Endo, K. Khoyama (2010) Recent trends in phosphate balance nationally and by region in Japan, NUTRIENT CYCLING IN AGROECOSYSTEMS, 86(1), 69- 77 (Residual N) 200 150 100 50 (Residual P) 200 150 100 50 1990 (kgN/ha) 1990 (kgP/ha)
description
140-19: Evaluation of Japanese Agricultural N and P Management by Integrated Environmental Impact Indicator in 1990 and 2005. Results and discussions. Reduce to STD condition. y = 265 + 6.09e-5x R= 0.482 (p
Transcript of Y= 5.42 +0.52X (p
0
5
10
15
20
25
0 5 10 15 20 25
Y=5.42+0.52X(p<0.01)
0
1 104
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Mg
N2O
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1 105
2 105
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0 5 107 1 108 1.5 108
TN-RealTN-STD
y = 4030 + 0.000867xR= 0.522 (p<0.01) y = 5100 + 0.000592xR= 0.343
0
5000
1 104
1.5 104
0 5 107 1 108
TP-RealTP-STD
y = 265 + 6.09e-5xR= 0.482 (p<0.01) y = 259 + 3.72e-5xR= 0.337 (p<0.01)
P-load potential N-load potentialP in
riv
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N in
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Reduce to STD condition
% of wells excess STD
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140-19: Evaluation of Japanese Agricultural N and P Management by Integrated Environmental Impact Indicator in 1990 and 2005.
S. Mishima and K. KohyamaNat. Ins. Agro-Env. Sci. Jpn
ctorEmissionFaNflowsOemissionN
pirationEvapotransnecipitatio
SurplusNleachingN
NAvairablePNSurplusPErosionloadNP
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Pr_
)],,([_,
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1. 61. 41. 21. 00. 8
IEIin 1990 IEI in 2005
Relative change of IEI
B
D
A
C
Fig.2 IEI distribution and its change and composition
Fig.1 Present state and emission target
Agricultural nitrogen (N) and phosphorus (P) use sometimes cause various negative environmental impacts. We set negative impacts as i) N and P load potential to surface water by erosion, ii) risk of ground water pollution by nitrate, and iii) contribution to global warming by nitrous oxide (N2O) emission, then estimate each negative impacts (Mishima et al. 2009, Mishima and Kohyama in review a,b). We found out that higher/lower negative impacts is not always caused by higher/lower N and P use or surplus in prefectural basis in Japan. To evaluate total negative impact in regional basis, building up integrated single indicator for environmental impact (IEI) would be necessary. For this purpose, we applied distance to target (DtT) method. In this poster, we indicated distribution of IEI and evaluated cause of regional higher IEI in Japan.
Introduction
Present state
P and N load (P and N indicator), N leaching potential and N2O emission was calculated by the formulas listed below. P and N indicator summarized watershed scales were significantly correlated with amount of P and N flow at the water quality monitoring points of the watersheds (Fig 1. A, B, blue dots). N leaching potential in prefectures significantly correlated with % of observation wells that excess water quality standard in the prefecture (Fig 1. C). N2O-N emission was estimated to be 48GgN in 1990 (Fig. 1. D)
Set the target, weighting each impacts and integrationThe targets were set as i)2ppm N and 0.1ppm P in river water as tentative target, ii)5.42ppm N that no well will expected to be excess water quality standard (10ppm N) and iii) cut 25% of N2O against 1990 by policy aim in each prefecture. Regression coefficients when river water P and N concentration is standardized as above (STD) was smaller than when real river water P and N concentration is set as 61% for P and 68% for N (Fig 1 A, B: purple dots). Weighting factors are 1.6 for P indicator (inversed value of 61%), 1.5 for N indicator (same as P), present potential of N leaching divided in each prefecture by 5.42 on risk of ground water pollution, and 1.3 (inversed value of 75%) for N2O emission in each prefecture. Integration as IEI was done in the below formula.
ValueNational
orinValueWeightIEI
_
20051990__
Method
IEI is higher in central Japan in both year (Fig 2 A,B). This trend is not same as N and P surplus. Numbers prefectures increased IEI was larger than reduced (Fig 2 C), although N and P surplus was generally reduced in 2005 than 1990 (Mishima et al. 2009, 2010, submitted a). Composition of IEI is indicated in Fig. 2D. Prefecture where IEI is mainly consisted with risk ground water pollution and N2O emission had is basically low IEI value and if prefectures where IEI contains high P and N load potential to river water indicate high IEI. Therefore, increase of IEI might be caused by increase of soil available N and P in 2005 than 1990 in prefectures.
Results and discussions
1) High N and P surplus is not always caused high IEI. The other environmental conditions such as erosion potential and precipitation2) Weight of P and N load potential might be important than risk of ground water pollution and N2O emission and are affected by soil available N and P.
Conclusion
S. Mishima, A. Endo, K. Kohyama (2009) Recent trend in residual nitrogen on national and regional scales in Japan and its relation with groundwater quality, NUTRIENT CYCLING IN AGROECOSYSTEMS, 83(1), 1-11S. Mishima, A. Endo, K. Khoyama (2010) Recent trends in phosphate balance nationally and by region in Japan, NUTRIENT CYCLING IN AGROECOSYSTEMS, 86(1), 69-77
( Resi dual N)
200150100 50
( Resi dual P)
200150100 50
1990 (kgN/ha) 1990 (kgP/ha)
