برآورد انتشار گازهای CH4، N2O و NOدر مزارع گندم و برنج خوزستان (مطالعه موردی: شوش و باغملک)

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشگاه حکیم سبزواری

2 گروه جغرافیا، دانشکده علوم اجتماعی، دانشگاه حکیم سبزواری

3 گروه علوم و مهندسی خاک، دانشکده کشاورزی، دانشگاه شهید چمران اهواز، اهواز، ایران

چکیده

افزایش غلظت گازهای گلخانهای طی چند دهه اخیر باعث ایجاد اثر گلخانهای در جو زمین و گرمتر شدن هوای آن شده است. پژوهش حاضر یک بررسی کاربردی تحلیلی است که با کمک مدلDAYCENT جهت مطالعه شار گازهای متان ( CH4)، نیتروس اکساید (N2O) ونیتریک اکساید ((NO درگندمزارهای شوش و شالیزارهای باغملک در خوزستان استفاده شد. همچنین تغییرات متوسط دمای سالانه هوا( oC1، 5/2 و 2/4) و بارش (2-، 7 و 14٪) جهت بررسینرخ شار گازهای متان، نیتروس اکساید و نیتریکاکساید شبیهسازی گردید. نتایج میانگینشار گاز متان در ایستگاه باغملک، 369/1، اکسید نیتروس 01/0 و اکسید نیتریک 01/0 تن در هکتار  در سال به دست آمد و برای ایستگاه شوش شار متان 106/0، اکسید نیتروس 101/0 و اکسید نیتریک 111/0 تن در هکتار در سالتعیین شد.گاز متان بیش‌ترین مقدار شار را در ایستگاه باغملک داشت. همچنین ایستگاه شوش،شار نیتروس اکساید و نیتریک اکساید بالاتری را نسبت بهایستگاه باغملک نشان داد. در ادامه بر اساس تغییرات دما در ایستگاه باغملک مقدار شار متان تقریباَ به صورت ثابت و مقدار تغییرات شار نیتروس اکساید و نیتریک اکساید بسیار ناچیز بدست آمد. در حالی که در ایستگاه شوش مقدار شار هر سه گاز با افزایش دما تغییر محسوسی را نشان داد. همچنین بر اساس تغییرات بارش در ایستگاه باغملک، شار متان مقدار ثابتی داشت، ولی شار نیتروس اکساید و نیتریکاکساید با زیاد شدن بارش، افزایش یافت. اما در ایستگاه شوش شار هر سه گاز با کاهش بارندگی کم و با افزایش آن زیاد شد. اختلاف بین مزارع برنج و گندم از نظر شار گازها به دلیل وضعیت هوازی و غرقابی بودن آنهاست.

کلیدواژه‌ها


عنوان مقاله [English]

Estimation of CH4, N2O and NO emissions in Khuzestan wheat and rice fields (Case study: Shush and Baghmalek)

نویسندگان [English]

  • nasrin moradimajd 1
  • Gholamabbas Fallah 2
  • Mansour Chatrenour 3
1 department hakim sabzevari university
2 Geomorphology & Meteorology Department, Faculty of Geography & Environmental Sciences, Hakim Sabzevari University, Sabzevar, Iran
3 Department of Soil Science and Engineering, Faculty of Agriculture, Shahid Chamran University of Ahvaz, Ahvaz, Iran
چکیده [English]

Introduction: Increasing concentration of greenhouse gases in recent decades has caused a greenhouse effect on the Earth's atmosphere and warmer air. One of  the main causes of global climate change and biodiversity is emission of greenhouse gases from various sources, especially from agricultural sector. Use of chemical fertilizers and pesticides, fossil fuels, crop soil management, livestock manure management in farms and incineration of organic residues are the most important sources of greenhouse gas emissions in agricultural sector. The most important of these gases are methane (CH4), nitrous oxide (N2O) and nitric oxide (NO). Aim of this study was to determine rate of emission of greenhouse gases in Shush wheat fields and Baghmalek paddy fields in Khuzestan province using DAYCENT model. Also, mean annual temperature changes (1, 2.5 and 4.2 oC) and precipitation (-2, 7 and 14%) were simulated to investigate emission rates of methane, nitrous oxide and nitric oxide.
Materials and methods: In this study, using existing data and documented sources, we retrieved history information in both study areas. Then, according to agricultural history, each area was written into agricultural daily events program for major land cultivation and both crops. As a result, several DAYCENT application files were created. DAYCENT model program is written in FORTRAN and C programming language and is used with UNIX / Linux platform.
Results and discussion: Results and Discussion: Using DAYCENT model, emission rates of methane, nitrous oxide and nitric oxide were simulated in both Baghmalek and Shousha stations. Simulated methane flux results of Baghmalek station, mean, minimum and maximum were 1.369, 0.805 and 1.701 tons per hectare per year, respectively. Percentage of change coefficient for methane emission in Baghmalek station was 3.6. Results of emitted nitrous oxide gas at Baghmalek station, mean, minimum and maximum were determined to be 0.01, 0.001 and 0.015 tons per hectare per year, respectively. Percentage of change coefficient for nitrous oxide emission in Baghmalek station was 1.2. Results of emitted nitric oxide gas at Baghmalek station were average, minimum and maximum of 0.01, 0.001 and 0.011 tons per hectare per year, respectively. Percentage change coefficient for nitric oxide emission in Baghmalek station was 0.5. Results of simulated methane emissions at Shush station, mean, minimum and maximum were determined to be 0.106, 0.043 and 0.101 tons per hectare per year, respectively. Percentage change coefficient for methane emission at Shush station was 3.9. Results of simulated nitrous oxide gas emission at Shush station were average, minimum and maximum of 0.101, 0.070 and 0.200 tons per hectare per year, respectively. Percentage change coefficient for nitrous oxide emission at Shush station was 67.3. Results of simulated nitric oxide gas emission at Shush station were determined as average, minimum and maximum of 0.111, 0.085 and 0.242 tons per hectare per year, respectively. Percentage change coefficient for nitric oxide emission at Shush station was 56.5. Results of the average methane emission at Baghmalek station (1.369 tons per hectare per year) were higher than Shush station (0.106 tons per hectare per year). For Baghmalek station, average emission of nitrous oxide and nitric oxide gas was equal (0.01 tons per hectare per year) and less than Shush station. Difference between rice and wheat fields in terms of emissions of studied gases is due to their aerobic status and flooding. Then, based on average, minimum and maximum emissions of methane, nitrous oxide and nitric oxide, with increasing average annual temperature of 1, 2.5 and 4.2 oC in Baghmalek paddy fields, trend of methane emissions was determined to be almost constant. And trend of nitrous oxide and nitric oxide emission changes was very small. Also, based on average, minimum and maximum emissions of methane, nitrous oxide and nitric oxide with increasing the average annual temperature of 1, 2.5 and 4.2 oC in Shush wheat fields, emission trend of all three gases changes significantly with increasing temperature. This trend reaches a maximum in increasing temperature by 4.2 oC and has an increasing trend. Then, based on average, minimum and maximum emissions of methane, nitrous oxide and nitric oxide with changes in precipitation of 2-, 7 and 14% in Baghmalek paddy fields with a change in precipitation, amount of methane emissions has a constant trend. And emissions of nitrous oxide and nitric oxide increase with increasing precipitation. Also, based on average, minimum and maximum emissions of methane, nitrous oxide and nitric oxide with changes in precipitation of 2-, 7 and 14% in Shush wheat fields with a change of -2%, we have a decrease in methane emissions. This trend increases with increasing rainfall by 7 and 14%. Also, emission of nitrous oxide and nitric oxide increases with decreasing rainfall and increases with increasing.
Conclusions: Based on comparison results of wheat and rice, the highest amount of methane was emitted in Baghmalek station (rice), the highest amount of nitrous oxide and nitric oxide was obtained from Shush station (wheat). According to results obtained from other studies difference between rice and wheat fields in terms of gas emissions is due to their aerobic status and flooding. In rice cultivation field with anaerobic conditions for a long time, it was observed that we have a high methane emission rate. Baghmalek rice paddies prevent release of nitrous oxide and nitric oxide because they are flooded. In these fields, because water content in the soil is higher than soil capacity, nitrous oxide is reduced to nitrogen. Nitric oxide is also released in rice paddy fields in form of pulses after fertilization and heavy rains. For these reasons, flux rates of nitrous oxide and nitric oxide were higher in wheat fields of Susa. Also, results of Shush wheat fields are consistent with results of other researchers.

کلیدواژه‌ها [English]

  • Baghmalek
  • Shush
  • Greenhouse Gases
  • DAYCENT model
  1. Ashtari, F., Sharififard, H., Shabankari, M., Kikavousi, A., Hashemifard, A., Afshan, A., Darvishi, N., 2014, Khuzestan Provincial, Green Book. (In persian)
  2. Bakht Firooz, A., Raeini Sarjaz, M., 2017, The effect of paddy drainage systems on methane emission reduction in greenhouse gas, Iranian Soil and Water Research, 44 (1): 1-10. (In persian)
  3. Fitton, N.,  Bindi, M., Brilli, L., Chicota, R., Dibari, C., Fuchs, K., Huguenin-Elie, O., Klumpp, K., Lieffering, M., Lüscher, A., Martin, R., McAuliffe, R., Merbold, L., Newton, P., Rees, R. M.,  Smith, P., Topp, C.F.E., Snow, V., 2019, Modelling biological N fixation and grass-legume dynamics with process-based biogeochemical models of varying complexity, European Journal of Agronomy,106:58-66.
  4. Hartman, M., Merchant, E.R., Parton, W.J., Gutmann, M.P., Lutz, S., Williams, S. A., 2011, Impact of historical land-use changes on greenhouse gas exchange in the U.S. Great Plains, 1883–2003, Ecological applications, 21(4):1105–1119.
  5. Hartman,  M. D. , Parton, W.J. , Del Grosso , S. J., Easter, M., Hendryx , J. , Hilinski ,T., Kelly, R., Keough, C.A. , Killian, K., Lutz, S., Marx, E., McKeown, R.,  Ogle, S., Ojima, D.S. , Paustian , K., Swan, A.  W. S., 2016, DayCent Ecosystem Model. Colorado State University.
  6. Intergovernmental Panel on Climate Change (IPCC), 2001, Climate Change 2001: Impacts, Adaptation, and Vulnerability(Eds J.J. McCarthy, O.F. Canziani, N.A. Leary, D.J. Dokken and K.S. White) 1032 pp. Cambridge University Press, Cambridge, UK.
  7. Intergovernmental Panel on Climate Change (IPCC), 2007, Summary for Policy Makers. The Physical Science Basis. Camb. Univ. Press. ISBN 0-444-42753-8, 7: 165-177.
  8. MAJ (Ministry of Agriculture of the IR of Iran), 2014, Planning and Economics Department, Statistics Bank of Iranian Agriculture.
  9. Malone, L. S., Keough, C., Staudhammer, C.L., Ryan, M. G., Parton, William J., Olivas, P., Oberbauer, S.F., Schedlbauer, J., Gregory, S. 2015. Ecosystem resistance in the face of climate change: a case study from the freshwater marshes of the Florida Everglades, Ecosphere, 6(4):1-23.

10. Mitchell, T.D., 2003, Pattern scaling: An Examination of the accuracy of the technique for describing future climates. Climatic Change, 60: 217-242.

11. Moradi, R., Pour Ghasemiyan, N., 2018, Investigation of greenhouse gas emissions and global warming potential due to the use of chemical inputs in the cultivation of important crops in Kerman province: - Cereals, Journal of Agricultural Ecology, 9 (2): 405-389. (In persian)

12. Safari, M., Abdi, R., 2016, Comparison of biogas production from rapeseed and wheat residues in combination with livestock manure, Journal of Agricultural Machinery, 6 (2): 476-487. (In persian)

13. Weiler, D. A.,  Tornquist, C. G., Zschornack, T.,  Ogle, S. M.,  Carlos, F. S.,  Bayer, C., 2018, Daycent Simulation of Methane Emissions, Grain Yield, and Soil Organic Carbon in a Subtropical Paddy Rice System, Revista Brasileira de Ciência do Solo, vol.42, ISSN 1806-9657.

14. Yao, Z., Zheng, X., Xie, B., Mei, B., Wang, R., Butterbach-Bahl, K., Zhu, J., and Yin, R., 2009, Tillage and crop residue management significantly affects N-trace gas emissionsduring the non-rice season of a subtropical rice-wheat rotation. Soil Biology and Biochemistry 41: 2131–2140.

15. Yue, Q., Cheng, K., Ogle, S., Hillier, J., Smith, P., Abdalla, M., Ledo, A., Sun, J. and Pan, G. 2019. Evaluation of four modelling approaches to estimate nitrous oxide emissions in China's cropland. Sci Total Environ., 20(652):1279-1289.