ارزیابی ترسیب کربن و پتانسیل گرمایش جهانی مزارع زعفران (مطالعه موردی: استان خراسان رضوی)

نوع مقاله: پژوهشی

نویسندگان

1 دانشگاه فردوسی مشهد

2 عضو هیات علمی پژوهشکده صنایع غذایی

3 دانشجوی کارشناسی ارشد دانشکده کشاورزی دانشگاه فردوسی مشهد

چکیده

مقدمه
افزایش غلظت دی اکسید کربن در اتمسفر، موجب افزایش توجه به بهبود ذخایر کربن خاک در اگرواکوسیستم‌ها به منظور تخفیف اثرات تغییر اقلیم و گرمای جهانی و بهبود کیفیت خاک شده است. مخازن کربن آلی خاک (SOC) نشاندهنده تعادل پویایی از ورودی‌ها و تلفات کربن است. تبدیل اکوسیستم‌های طبیعی به اگرواکوسیستم‌ها باعث تخلیه مخازن کربن آلی خاک می‌شود. این تلفات در شرایط خروجی کربن بالاتر در مقایسه با ورودی آن و تخریب خاک تشدید می‌شود. اکوسیستم‌های خشکی سهم زیادی در غنی‌سازی دی اکسید کربن اتمسفری دارند.
ترسیب کربن به معنای انتقال دی اکسید کربن اتمسفر به مخازن زنده و حفظ آن برای جلوگیری از تلفات سریع آن است. بنابراین، ترسیب کربن خاک به معنای افزایش مخازن کربن آلی و غیرآلی از طریق عملیات کاربری زمین و مدیریت زراعی توصیه شده می‌باشد.
اهداف این مطالعه تعیین ضرایب تبدیل، وزن خشک، کربن آلی، ترسیب کربن اندام‌های هوایی و زیرزمینی و برآورد انتشار گازهای گلخانه‌ای مزارع زعفران در استان خراسان رضوی بود.
مواد و روش‌ها
این آزمایش در قالب طرح پایه کاملاً تصادفی در سال 1395 انجام شد. نمونه‌برداری به روش تصادفی- سیستماتیک از 10 مزرعه در قالب 30 پلات 5/0 متر مربعی در طول سه ترانسکت 50 متری اجرا گردید. اندام‌های زیرزمینی با استفاده از سیلندر نمونه‌برداری و سپس از خاک به طور کامل جدا شدند. بعد از نمونه‌برداری، اندام‌های هوایی (شامل گل و برگ) از اندام‌های زیرزمینی (شامل فلس و بنه) به ترتیب برای اندازه‌گیری زیست‌توده اندام هوایی و زیرزمینی جدا شدند. اندام‌های هوایی و زیرزمینی به طور کامل برای رسیدن به وزن ثابت خشک و به عنوان وزن ماده خشک ارائه گردید. برای تعیین ضرایب تبدیل اندام‌های هوایی و زیرزمینی از روش احتراق به طور جداگانه استفاده شد. سپس پتانسیل ترسیب کربن اندام‌های هوایی و زیرزمینی زعفران و خاک اندازه‌گیری شد.
در نهایت، پس از محاسبه میزان انتشار گازهای گلخانه‏ای شامل دی‌ اکسید کربن (CO2)، اکسید نیتروژن (N2O) و متان (CH4) با استفاده از ضرایب انتشار، پتانسیل گرمایش جهانی تعیین گردید.
به منظور آنالیز داده‌ها، آنالیز واریانس و مقایسه میانگین با روش روش حداقل اختلاف معنی‌دار با استفاده از نرم‌افزار SAS 9.3 انجام شد.
یافته‌ها
بر اساس نتایج این آزمایش، وزن خشک، محتوی کربن آلی، ضرایب تبدیل و ترسیب کربن اندام‌های هوایی و زیرزمینی زعفران به طور معنی‌داری متفاوت بودند (01/0p≤). میانگین عملکرد اندام‌های زیرزمینی بالاتر از اندام‌های هوایی بود. بالاترین و پایین‌ترین ترسیب کربن اندام‌های هوایی و زیرزمینی به ترتیب برای بنه و گل با 83/5 و 14/0 تن در هکتار محاسبه شد. بیشترین مجموع انتشار گازهای گلخانه‌ای برای سوخت‌های فسیلی 78/39 کیلوگرم معادل دی‌اکسید کربن به ازای یک هکتار و پتانسیل گرمایش جهانی برابر با 21/7 تن معادل دی اکسید کربن به ازای یک هکتار محاسبه گردید.
نتیجه‌گیری
بدین‌ترتیب، مدیریت ارگانیک و مصرف بقایای گیاهی و کودهای دامی و آلی را می‌توان به عنوان راهکارهای اکولوژیک در جهت بهبود پتانسیل ترسیب کربن مزارع زعفران مدنظر قرار داد که از طریق کاهش انتشار گازهای گلخانه‌ای، تخفیف تغییر اقلیم را نیز تحت تأثیر قرار می‌دهد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Evaluating the potential of carbon sequestration and global warming potential for saffron fields (Case study: Khorasan-e Razavi Province)

چکیده [English]

Introduction
Increases in the concentration of CO2 in the atmosphere have prompted renewed interest in enhancing the soil pools of carbon in the agroecosystems to mitigate climate change and global warming and also improve quality of soil. The soil organic carbon (SOC) pool represents a dynamic equilibrium of gains and losses of carbon. Conversion of natural ecosystems to agroecosystems causes depletion of the SOC pools. The depletion is intensified when the output of carbon exceeds the input and when soil degradation is intensity. Terrestrial ecosystems contributed to atmospheric CO2 enrichment.
Carbon sequestration implies transferring atmospheric CO2 into long-lived pools and storing it securely so it is not immediately loosed. Thus, soil carbon sequestration means improving SOC and soil inorganic carbon pools through land use and recommended management practices.
Our purposes were to determine a set of coefficients for calculating conversion coefficients, dry weight, organic carbon and carbon sequestration of above-ground and below-ground tissues for saffron in Khorasan-e Razavi province.

Materials and Methods
A survey experiment was conducted based on a completely randomized design during 2016. Sampling was performed with random-systematic method from 10 fields by using 30 plots of 0.5 m2 and along three transects of 50 m. Below-ground tissues by using cylinder were manually sampled and then separated from the soil. After sampling, the above-ground tissues (such as flower and leaf) were separated from below-ground tissues (including tunic and corm) as to measure the above-ground and below-ground biomasses, respectively. Above-ground and below-ground biomasses were separately dried to constant weight and expressed on a dry matter basis. Conversion coefficients of above- ground and below- ground tissues were determined with combustion method separately. Then, sequestration carbon potential for above- ground and below- ground tissues of saffron and soil were computed.
Final, after the calculation of emission for greenhouse gases including CO2, N2O and CH4 based on emission indices, global warming potential (GPW) were calculated.
For statistical analysis, analysis of variance and least significant difference (LSD) were performed using SAS version 9.3.

Results
The results showed that dry weights, organic carbon contents, conversion coefficients and carbon sequestration for above- ground and below- ground tissues of saffron were significantly different. Biomass of below- ground tissues were higher than above- ground tissues. The highest and lowest carbon sequestration for above- ground and below- ground tissues were calculated for corm and flower with 5.83 and 0.14 t.ha-1, respectively. The highest emission of greenhouse gas was belonged to fossil fuels with 39.78 kg. Equiv. CO2 and GWP was computed 7.21 t Equiv. CO2 per one ha.

Conclusion
It is therefore concluded that organic management and use of crop residues, cow manure and organic fertilizers seems to be a rational ecological approach for sustainable management of saffron agroecosystem with a consequence of reduction in greenhouse gases and mitigation of climate change.

کلیدواژه‌ها [English]

  • Greenhouse emission
  • Climate Change
  • Cow manure
  • Ecological approach
1. Abdi, N., Maadah Arefi, H. and Zahedi Amiri, G. 2008. Estimation of carbon sequestration in Astragalus rangelands of Markazi province (Case study: Malmir rangeland in Shazand region). Iran. J. Range Desert Resour., 15: 2.269-282. (In Persian with English Summary)

2. Abdullaer, F. and Espinosa-Agirre, J.J. 2004. Biomedical properties of saffron and itspotential use in cancer therapy and chemoprevention trials cancer detection and prevention.Cancer Detect. Prevn., 23: 426-432.
3. Abrishamchi, P. 2003. Investigatuon about some biochemical changes related to breaking ofdormancy and flower formation in Crocus sativus L. 3rd National Symposium on Saffron.
Proceedings of the 3rd National Symposium on Saffron. Mashhad, Iran, 2-3 December, p. 19-27. (In Persian with English Summary)
4. Afrazeh, Z., Bolandi, M., Khorshidi, M. and Mohammadi Nafchi, A. 2014. Evaluation of antioxidant activity of aqueous and alcoholic extracts (methanol, ethanol) saffron petals.
Saffron Agron. Tech., 2(3): 231-236. (In Persian with English Summary)
5. Arslan, N., Gubruz, B., Đpek, A., Özcan, S., Sarthan, E., Daeshian, A. and Moghaddassi, M.
2006. The effect of corm size and different harvesting time on saffron (Crocus sativus L.)
regeneration. II. International Symposium on Saffron: Proceedings of the 2nd International
Symposium on Saffron Biology and Technology. Mashhad, Iran, 28-30 October, Pp: 113-
117.
6. Azizi Zohan, A.A. and Pasandide, M. 2013. Investigate the causes of the decline in
agricultural production after a period of cultivation of saffron. J. Land Manage. 1: 1. 91-98.
(In Persian with English Summary)
7. Banaeian, N., Omid, M. and Ahmadi, H. 2011. Energy and economic analysis of greenhouse
strawberry production in Tehran province of Iran. Energ. Convers. Manage. 52: 1020-1025.
8. Behniya, M.R. 1991. Saffron. Tehran Univ. Press, 310p. (In Persian)
9. Black, C.A. 1965. Methods of Soil Analysis. (V.I). Am. Soc. Agron. 1572p.
10.Bordbar, S.K. and Mortazavi Jahromi, S.M. 2008. Carbon sequestration potential of
Eucalyptus camaldulensis Dehnh. and Acacia salicina Lindl. plantation in western areas of
Fars province. Agron. J. (Pajouhesh Sazandegi). 70: 95-103. (In Persian with English
Summary)
11.Chambers, J.C. and Brown, R.E. 1983. Methods for vegetation sampling and analysis on
revegetated mined lands. Intermountain Forest and Range Experiment Station. General
Technical Report. Int.
12.Dastan, S., Soltani, A., Noormohamadi, G. and Madani, H. 2014. CO2 emission and global
warming potential (GWP) of energy consumption in paddy field production systems. J.
Agroecol. 6(4): 823-835. (In Persian with English Summary)
13.Dayer, J.A. and Desjardins, R.L. 2003. The impact of farm machinery management on the
greenhouse gas emissions from Canadian agriculture. J. Sustain. Agric. 22: 59-74.
14.Earth System Research Laboratory. 2016. Ed Dlugokencky and Pieter Tans, NOAA/ESRL
(www.esrl.noaa.gov/gmd/ccgg/trends/)
15.Environmental Protection Agency (EPA). 1998. National Air Quality and Emission Trends
Report, Report EPA 454/R-00-003, 2000.
16.Fallahi, H.R., Rezvani-Moghaddam, P., Behdani, M.A., Aghhavani-Shajari, M., Jahedi Pour,
S. and Yari, A. 2015. Principles of Carbon Sequestration. Jihad Daneshgahi of Mashhad.
Press, 351p. (In Persian)
17.Falloon, P.D., Smith1, P., Smith, J.U., Szabó, J., Coleman, K. and Marshall, S. 1998.
Regional estimates of carbon sequestration potential: linking the Rothamsted Carbon Model
to GIS databases. Biol. Fert. Soil., 27: 3.236-241.
18.Follett, R.F., Castellanos, J.Z. and Buenger, E.D. 2005. Carbon dynamics and sequestration
in an irrigated Vertisol in Central Mexico. Soil Till. Res., 83: 148-158.
19.Forouzeh, M.R., Heshmati, G.A., Mesbah, H. and Ghanbarian, G.A. 2008. Effect of
floodwater irrigation on carbon sequestration potential of Helianthemum lippii (L.) Pers.,
Dendrostellera lessertii Van Tiegh. and Artemisia sieberi Besser in the Gareh Bygone plain:
A case study. Agron. J. (Pajouhesh Sazandegi). 78: 11-19. (In Persian with English
Summary)
20.Ghanbariyan, G., Hasan Li, A. and Rajabi Nooghab, V. 2015. Comparing potential carbon
sequestration of different parts of mountain almond and grape plants and soil in Fars
province. J. Nat. Environ. 68(2): 257-265. (In Persian with English Summary)
21.Ghorbani, R. and Koocheki, A. 2006. Organic saffron in Iran: prospects challenges.
Proceedings of the 2nd International Symposium on Saffron Biology and Technology.
Mashhad, Iran, 28-30 October, Pp: 369-374.
22.Gioccio, M. 2004. Crocetin from saffron: an active component of an ancient spice. Crit. Rev.
Food Sci. Nutr. 44: 155-172.
23.Guillou, C.L., Angers, D.A., Leterme, P. and Menasseri-Aubry, S. 2011. Differential and
successive effects of residue quality and soil mineral N on water-stable aggregation during
crop residue decomposition. Soil Biol. Biochem. 43: 1955-1960.
24.Hasannezhad, M., Tamartash, R. and Tatiyan, M.R. 2014. Comparison of carbon
sequestration of Astragalus gossypinus and Dactylis glomerata species in Hezarjarib
mountainous rangelands, Behshahr. J. Environ. Stud. 40: 1. 29-38. (In Persian with English
Summary)
25.Heinemann, A.B., Maia, H.N., Dourado-Neto, A.D., Ingram, K.T. and Hoogenboom, G.
2005. Soybean (Glycine max L. Merr.) growth and development response to CO2 enrichment
under different temperature regimes. Eur. J. Agron. 24: 52-61.
26.Hill, M.J., Braaten, R. and McKeon, G.M. 2003. A scenario calculator for effects of grazing
land management on carbon stocks in Australian rangelands. Environ. Model. Soft. 18: 7.
627-644.
27.IPCC. 2006. IPCC Guidelines for National Greenhouse Gas Inventories. Intergovernmental
panel on climate change. Greenhouse Gas Inventory Reference Manual, Vol. 4.
28.IPCC. 2007. Summary for Policy Makers. Climate Change 2007: The Physical Science
Basis. Contribution of Working Group I to the Fourth Assessment Report. Cambridge
University Press, Cambridge.
29.Jafarian, Z. and Tayefeh Seyyed Alikhani, L. 2013. Carbon sequestration potential in dry
farmed wheat in Kiasar region. Agric. Knowl. Sustain. Prod. 23: 1. 31-41. (In Persian with
English Summary)
30.Jihad Keshavarzi Khorasan Razavi. 2015. Statistical Year book of agriculture. Jihad
Keshavarzi Khorasan Razavi. Mashhad, Iran. (In Persian)
31.31-Kaltsas, A.M., Mamolos, A.P., Tsatsarelis, C.A., Nanos, G.D., and Kalburtji, K.L. 2007.
Energy budget in organic and conventional olive groves. Agric. Ecosyst. Environ. 122(2):
243-251.
32.Khorramdel, S. and Gholizadegan Ehsanabad, A. 2015. Study greenhouse gas emissions and
global warming potential production systems potatoes. The first international and the fourth
notional conference of IRANs Environmental and Agricultural Research. Hamedan, Iran, 26
November 2015. http://www.civilica.com/Paper-NCER04-NCER04_062.html. (In Persian)
33.Khorramdel, S., Rezvani Moghaddam, P. and Jafari, L. 2016. Evaluating the potential of
carbon sequestration for canola fields under Khorasan Razavi. Sci. Nat. Resour. 9(3): 22-43.
(In Persian with English Summary)
34.Khorramdel, S., Shabahang, J., Amin Ghafori, A. and Gholizadegan Ehsanabad, A. 2015.
Evaluating the greenhouse gas emissions in Pistachio production (Case study: Khorasan).
First international congress of Healthy Agriculture, Healthy Nutrient and San Society.
Tehran, Iran, July. (In Persian)
35.Khorramdel, S., Koocheki, A. and Rezazadeh, M. 2014. The effects of climate change and
global warming potential on biodiversity. National Conference on Climate Change and
Engineering Agric. Natural Resources. Hamedan, Iran, 26 June 2014.
http://www.civilica.com/Paper-CCASD01-CCASD01_255.html (In Persian)
36.Khorramdel, S., Mollafilabi, A. and Gholizadegan Ehsanabad, A. 2015. Evaluating the
global warming potential in saffron production (Case study: Khorasan). International
conference on sustainable development with a focus on agriculture, environment and
tourism. Tabriz, Iran, 16-17 September 2015. http://www.civilica.com/Paper-ICDAT01-
ICDAT01_068.html. (In Persian)
37.Koocheki, A., Ganjeali, A. and Abbassi, F. 2006. The effect of duration of incubation and
photoperiod on corm and shoot characteristics of saffron plant (Crocus sativus L.).
Proceedings of the 2nd International Symposium on Saffron Biology and Technology.
Mashhad, Iran, 28-30 October. Pp: 61-70.
38.Koocheki, A., Tabrizi, L., Jahani, M. and Mohamad Abadi, A.A. 2011. The effect of high
density and depth of planting on agronomic characteristic of saffron (Crocus sativus L.) and
corms behavior. Agroecol. 3: 36- 40. (In Persian with English Summary)
39.Kukal, S.S., Rasool, R. and Benbi, D.K. 2009. Soil organic carbon sequestration in relation
to organic and inorganic fertilization in rice–wheat and maize–wheat systems. Soil Till. Res.
102: 87–92.
40.Lal, R. 2003. Global potential of soil carbon sequestration to mitigate the greenhouse effect,
Crit. Rev. Plant Sci., 22: 2. 151-184.
41.Lal, R. and Kimble, J.M. 1997. Conservation tillage for carbon sequestration. Nutr. Cycl.
Agroecosys. 49(1-3): 243-253.
42.Lal, R. 2004. Soil carbon sequestration to mitigate climate change, Geoderma. 123: 1-22.
43.Ma, Z. 1999. Carbon sequestration by switchgrass. PhD Thesis of Graduated Faculty of
Auburn, University, Alabama. 124p.
44.McCarty, G.W. and Ritcher, J.C. 2000. Impact of soil movement on carbon sequestration in
agricultural ecosystems. Advances in Terrestrial Ecosystem Carbon Inventory,
Measurements, and Monitoring Conference. In Raleigh, North Carolina 3-5.
45.Meteorological Organization of Khorasan Razavi. http://www.razavimet.ir/fa/node/38. (In
Persian)
46.Mohammad Abadi, A.A., RezvaniMoghaddam, P. and Sabori, A. 2006. Effect of plant
distance on flower yield and qualitative and quantitative characteristics of forage production
of saffron (Crocus sativus L.) in Mashhad conditions. Proceedings of the 2nd International
Symposium on Saffron Biology and Technology. Mashhad, Iran, 28-30 October. Pp: 151-
153.
47.Moradi, M. 2008. Economic and environmental study Iran's Zagros forests (Case study:
Kohgiluyeh and Boyer Ahmad). Ph.D. Thesis of Islamic Azad University, Science and
Research Branch of Tehran. 299p. (In Persian with English Summary)
48.Mortenson, M. and Schuman, G. 2002. Carbon sequestration in rangeland interseeded with
yellow-flowering alfalfa (Medicago sativa Spp. Falcata) USDA Symposium on Natural
Resource Management to Offset Greenhouse Gas Emission in University of Wyoming.
49.Najmoddini, N. 2013. Effects of mechanical structural operations to improve watershed
management in carbon sequestration for climate change mitigation (Case Study: Watershed
Gavdareh in Kurdistan province). The 2nd National Conference on Climate Change and
Agriculture, August 23, Urmia, Iran. (In Persian)
50.Nassiri Mahallati, M., Koocheki, A., Mansoori, H. and Moradi, R. 2015. Long term
estimation of carbon dynamic and sequestration for Iranian agro-ecosystem: I- Net primary
productivity and annual carbon input for common agricultural crops. J. Agroecol. 6(4): 741-
752. (In Persian with English Summary)
51.Nobakht, A., Pourmajidian, M., Hojjati, S.M. and Fallah, A. 2011. A comparison of soil
carbon sequestration in hardwood and softwood monocultures (Case study: Dehmian forest
management plan, Mazindaran). Iran. J. Forest. 3: 1. 13-23. (In Persian with English
Summary)
52.Nosetto, M.D., Jobbagy, E.G. and Paruelo, J.M. 2006. Carbon sequestration in semi-arid
rangelands: comparison of Pinus ponderosa plantations and grazing exclusion in NW
Patagonia. J. Arid Environ., 67: 142-156.
53.Polidori, A., Turpin, B.J., Davidson, C.I., Rodenburg, L.A. and Maimone, F. 2008. Organic
PM 2.5: fractionation by polarity, FTIR spectroscopy, and OM/OC ratio for the Pittsburgh
aerosol. Aerosol. Sci. Technol., 42: 233-246.
54.Poor Asghar Sangachin, F. 2007. Look at the state of forest destruction in Iran and the world.
J. Sustain. Dev. Environ., 1: 3. 36-69. (In Persian with English Summary)
55.Prior, S.A., Torbert, H.A., Runion, G.B., Rodgers, H.H., Wood, C.W., Kimball, B.A.,
LaMorte, R.L., Pinter, P.J. and Wall, G.W. 1997. Free- air carbon dioxide enrichment of
wheat: soil carbon and nitrogen dynamics. J. Environ. Qual., 26: 1161-1166.
56.Rodhe, H. 1990. A comparison of the contribution of various gases to the greenhouse. Sci.
248: 1217-1219.
57.Roozi Talab, M.H. 2007. Effects of climate change on agriculture and stability of arid and
semiarid soils in Iran and the world. Tenth Congress of Soil Science. Karaj, Iran, 26-28
August. (In Persian)
58.Schimel, D.S. 1995. Terrestrial ecosystems and the carbon cycle. Glob. Change Biol., 1: 1.
77–91.
59.Smit, B. and Skinner, M.W. 2002. Adaptation options in agriculture to climate change: a
typology. Mitig. Adapt. Strat. Glob. Chang., 7: 85–114.
60.Smith, P. and Fang, C.M. 2010. Carbon cycle: a warm response by soils. Nature. 464: 499–
500.61.Smith, W.N., Grant, B., Desgardins, R.L., Lemke, R. and Li, C. 2004. Emission of the interannual N2O emission from agricultural soils in Canada. Nutr. Cycl. Agroecosys. 68: 37-45.62.Snyder, C.S., Bruulsema, T.W., Jensen, T.L. and Fixen, P.E. 2009. Review of greenhousegas emissions from crop production systems and fertilizer management effects. Agric.Ecosys. Environ., 133: 247-266.سرور خرمدل و همکاران2963.Tamartash, R., Tatian, M.R. and Yousefian, M. 2012. The ability of different vegetativeforms to carbon sequestration in plain rangeland of Miankaleh. J. Environ. Stud., 38: 62. 45-54. (In Persian with English Summary)64.Tarkalson, D.D., Brown, B., Kok, H. and Bjorneberg, D.L. 2009. Irrigated small-grainresidue management effects on soil chemical and physical properties and nutrient cycling.Soil Sci. 174: 303-311.65.Tzilivakis, J., Warner, D.J., May, M., Lewis, K.A. and Jaggard, K. 2005. An assessment ofthe energy inputs and greenhouse gas emissions in sugar beet (Beta vulgaris) production inthe UK. Agric. Syst., 85: 101-119.66.Walkley, A. and Black, I. 1934. An examination of the Degtjareff method for determiningsoil organic matter and a proposed modification of the chromic acid titration method. SoilSci. Soc. Am. J. 37: 29-38.67.Wiesmeier, M., Hübner, R., Spörlein, P., Geuß, U., Hangen, E., Reischl, A., Schilling, B.,Lützow, M. and Kögel-Knabner, I. 2014. Carbon sequestration potential of soils in southeastGermany derived from stable soil organic carbon saturation. Glob. Change Biol. 20: 2. 653–665.68.Wood, S. and Cowie, A. 2004. A review of greenhouse gas emission factors for fertilizerproduction. Research and Development Division, State Forests of New South Wales.Cooperative Research Center for Greenhouse Accounting.69.Yousefi, M., Mahdavi Damghani, A.M. and Khorramivafa, M. 2014. Energy consumption,greenhouse gas emissions and assessment of sustainability index in corn agroecosystems ofIran. Sci. Total Environ. 493: 330–335.70.Zhang, L., Zhuang, Q., He, Y., Liu, Y., Dongsheng, Y., Zhao, Q., Shi, X., Xing, S. andWang, G. 2016. Toward optimal soil organic carbon sequestration with effects of agriculturalmanagement practices and climate change in Tai-Lake paddy soils of China. Geoderma. 275:28–39.