Supplement:

To further clarify what kind of methods, soils, experimental methods derived from the database of this study, we compiled a list of the source data from peer-reviewed journals. S1 showsa list citation of the references with their respective measurement season, site, and method. S2 shows the detail of soil characteristics of experimental sites mentionedabove in the TaihuLake region.

S1: A list citation of the source data with their respective measurement season, site, and method.

Item / Season / Site / Method / Reference
Yield
1998-2002 / Changshu / Monolith Lysimeter / Wang et al.(2007)
1998-2001 / Xiqiao / Field experiments / Wang et al.(2004)
1994 / Nanjing / Field experiments / Cai et al.(1997)
1995-1998 / Jurong
Wuxi / Field experiments / Roelcke et al.(2004)
1996-1997 / Wuxi / Field experiments / Cui et al.(1998)
2002-2003 / Changshu / Field experiments / Fan et al.(2005)
2003-2005 / Yixing / Field experiments / Ma(2008)
Leaching
2003-2005 / Changshu / Monolith Lysimeter / Xie et al.(2007)
1998-2002 / Changshu / Monolith Lysimeter / Wang et al.(2007)
1996-1997 / Wuxi / Field experiments / Cui et al.(1998)
2005-2006 / Changshu / Monolith Lysimeter / Zhang et al.(2008a)
2004 / Jiading / Field experiments / Huang et al.(2007)
2003-2006 / - / Field experiments / Ju et al.(2009)
2006 / Changshu / Monolith Lysimeter / Zhang et al.(2008b)
2003 / Changshu / Monolith Lysimeter / Zhao et al.(2009)
Runoff
1998-2002 / Changshu / Monolith Lysimeter / Wang et al.(2007)
2002-2003 / Changshu / field experiments / Tian et al.(2007)
2003-2005 / Jiaxing / field experiments / Liang et al.(2007)
2004 / Wujiang / field experiments / Jiao et al.(2007)
2003 / Jiading / field experiments / Lu et al.(2006)
NH3
1998-2002 / Changshu / Monolith Lysimeter / Wang et al.(2007)
2003 / Changshu / Monolith Lysimeter / Zhao et al.(2009)
2003-2005 / Jiaxing / field experiments / Liang et al.(2007)
2003-2006 / - / Field experiments / Ju et al.(2009)
2002-2003 / Changshu / Field experiments / Tian et al.(2007)
2003-2004 / Changshu / Field experiments / Deng et al.(2006)
N2O
1994 / Nanjing / Field experiments / Cai et al.(1997)
2003 / Changshu / Monolith Lysimeter / Zhao et al.(2009)
2003-2005 / Yixing / Field experiments / Ma(2008)
2002-2003 / Nanjing / Field experiments / Zou et al.(2005)
2000-2001 / Nanjing / Field experiments / Zou et al.(2003)
2001-2003 / Wuxi / Field experiments / Zheng et al.(2004)
1993-1994 / Suzhou / Field experiments / Xing and Zhu(1997)
1994-1997 / Suzhou / Field experiments / Zheng et al.(2000)
Site / Organic
C (%) / Total
N (%) / CEC (c mol kg-1) / pH / Location
JiaDing / 2.73 / 0.16 / 15.54 / 6.35 / 31°.40´N,121°.24´E
Xiqiao / 2.78 / 0.18 / 15.0 / 5.5 / 31°.43´N,120°.44´E
Jiaxing / 2.32 / 0.19 / 15.15 / 6.3 / 30°.77´N,120°.76´E
Changshu / 2.0 / 0.18 / 20.2 / 7.36 / 32°.33´N,118°.42´E
Nanjing / 1.85 / 0.12 / - / 7.99 / 32°.00´N,118°.48´E
Jurong / 0.89 / 0.10 / - / 6.3 / 32°.00´N,119°.10´E
Wuxi / 1.66 / 0.17 / - / 6.8 / 31°.37´N,120°.28´E
Yixing / 1.26 / 0.13 / - / 6.23 / 31°.17´N,119°.54´E
Wujiang / 1.89 / 0.16 / 11.6 / 5.6 / 31°.32´N,120°.56´E
Suzhou / 4.46 / 0.27 / 26.4 / 7.15 / 31°.16´N,120°.38´E

S2. Soil characteristics of experimental sites in TaihuLake region

References:

Cai, Z., G. Xing, X. Yan, H. Xu, H. Tsuruta, K. Yagi, and K. Minami. 1997. Methane and nitrous oxide emissions from rice paddy fields as affected by nitrogen fertilizers and water management. Plant and Soil 196:7-14.

Cui, Y.T., X. Cheng, C.R. Han, and R.G. Li. 1998. Rice nitrogen utilization efficiency and nitrogen leaching amount in Taihu Lake watershed of south Jiangsu Province. Journal of China Agricultural University 3:51-54 (in Chinese).

Deng, M.H., B. Yin, S.L. Zhang, Z.L. Zhu, and S.X. J. 2006. Effects of rate and method of N application on ammonia volatilization in paddy fields. Soils 38:263-269 (in Chinese).

Fan, X.H., Y.S. Song, D.X. Lin, L.Z. Yang, and J.M. Zhou. 2005. Ammonia volatilization losses from urea applied to wheat on a paddy soil in Taihu region, China. Pedosphere 15:59-65.

Huang, M.W., M. Liu, M. Lu, L.J. Hou, D.N. Ou, and X. Lin. 2007. Study on the nitrogen leaching in the paddy-wheat rotation agroecosystem. Acta Scientiae Circumstantiae 27:629-636 (in Chinese).

Jiao, S.J., X.M. Hu, G.X. Pan, H.J. Zhou, and X.D. Xu. 2007. Efects of fertilization on nitrogen and phosphorus run-of loss from Qingzini paddy soil in Taihu Lake region during rice growth season. Chinese Journal of Ecology 26:495-500 (in Chinese).

Ju, X.T., G.X. Xing, X.P. Chen, S.L. Zhang, L.J. Zhang, X.J. Liu, Z.L. Cui, B. Yin, P. Christie, and Z.L. Zhu. 2009. Reducing environmental risk by improving N management in intensive Chinese agricultural systems. Proceedings of the National Academy of Sciences 106:3041-3046.

Liang, X.Q., Y.X. Chen, H. Li, G.M. Tian, W.Z. Ni, M.M. He, and Z.J. Zhang. 2007. Modeling transport and fate of nitrogen from urea applied to a near-trench paddy field. Environmental Pollution 150:313-320.

Lu, M., M. Liu, M.W. Huang, and G.F. Mao. 2006. Field Study of Nitrogen Loss in Soil with Rice- wheat Rotation System. Journal of Agro-Environment Science 25:1234-1239(in Chinese).

Ma, J. 2008. Effect of straw and nitrogen fertiliser on CH4 and N2O emissions from rice fields, Chinese Academy of Sciences, Nanjing.

Roelcke, M., Y. Han, K.H. Schleef, J.G. Zhu, G. Liu, Z.C. Cai, and J. Richter. 2004. Recent trends and recommendations for nitrogen fertilization in intensive agriculture in eastern China. Pedosphere 14:449-460.

Tian, Y.H., F.Y. He, B. Yin, and Z.L. Zhu. Ammonia volatilization from paddy fields in the Taihu Lake Region as affected by N and P combination in fertilization. Acta Pedologica Sinica 44:893-900.

Tian, Y.H., B. Yin, L.Z. Yang, S.X. Yin, and Z.L. Zhu. 2007. Nitrogen runoff and leaching losses during Rice-Wheat rotations in Taihu Lake Region, China. Pedosphere 17:445-456.

Wang, D.J., Q. Liu, J.H. Lin, and R.J. Sun. 2004. Optimum nitrogen use and reduced nitrogen loss for production of rice and wheat in the Yangtse Delta region. Environmental Geochemistry and Health 26:221-227.

Wang, X.Z., J.G. Zhu, R. Guo, H. Yasukazu, and K. Feng. 2007. Nitrogen cycling and losses under Rice-Wheat rotations with coated urea and urea in the Taihu Lake Region. Pedosphere 17:62-69.

Xie, Y.X., Z.Q. Xiong, G.X. Xing, G.Q. Sun, and Z.L. Zhu. 2007. Assessment of nitrogen pollutant sources in surface waters of Taihu lake region. Pedosphere 17:200-208.

Xing, G.X., and Z.L. Zhu. 1997. Preliminarystudies on N2O emission fluxes from upland soils and paddysoils in China. Nutrient Cycling in Agroecosystems 49:17-22.

Zhang, J., D.J. Wang, and C. Wang. 2008a. On nutrient leaching amount of Rice-Wheat rotation field with monolith lysimeter in Taihu Lake Area. Soil 40:591-595 (in Chinese).

Zhang, J., D.J. Wang, and C. Wang. 2008b. Nitrogen and phosphorus balance under paddy field irrigation-drainage system in south Jiangsu Plain. Acta Pedologica Sinica 45:657-662 (in Chinese).

Zhao, X., Y. Xie, Z. Xiong, X. Yan, G. Xing, and Z. Zhu. 2009. Nitrogen fate and environmental consequence in paddy soil under rice-wheat rotation in the Taihu Lake region, China. Plant and Soil 319:225-234.

Zheng, X., S. Han, Y. Huang, Y. Wang, and M. Wang. 2004. Re-quantifying the emission factors based on field measurements and estimating the direct N2O emission from Chinese croplands. Global Biogeochemical Cycles 18:1-19.

Zheng, X.H., M.X. Wang, Y.S. Wang, R.X. Shen, J. Gou, J. Li, J.S. Jin, and L.T. Li. 2000. Impacts of soil moisture on nitrous oxide emission from croplands: a case studyon rice based agro-ecosystem in Southeast China. Chemosphere 2:207-214.

Zou, J.W., Y. Huang, Y. Lu, X.H. Zheng, and Y.S. Wang. 2005. Direct emission factor for N2O from rice–winter wheat rotation systems in southeast China. Atmospheric Environment 39:4755-4765.

Zou, J.W., Y. Huang, L.G. Zong, J.Y. Jiang, X.H. Zheng, and Y.S. Wang. 2003. Effects of water regime and straw application in paddyrice season on N2O emission from following growing season. Agricultural Science in China 2:68-74.