پهنه‌بندی اقلیمی- احتمالاتی اراضی کشاورزی استان گلستان برای کشت گندم دیم (Triticum aestivum L.)

نوع مقاله : علمی - پژوهشی

نویسنده

دانشگاه آزاد اسلامی واحد گرگان

چکیده

ﺗﺤﻠﯿﻞﻫﺎی اﺣﺘﻤﺎﻻﺗﯽ ﻣﯽﺗﻮاﻧﺪ ﺿﻤﻦ اﻓﺰاﯾﺶ اﻧﻌﻄﺎفﭘﺬﯾﺮی در ﺗﺼﻤﯿﻢﮔﯿﺮیﻫﺎ، ﺿﺮﯾﺐ اﻃﻤﯿﻨﺎن ﺗﺼﻤﯿم­ها را ﻧﯿﺰ افزایش دهد. نقش تأثیرگذار عوامل اقلیمی در پهنه­بندی اراضی برای کشت گیاه از یک سو و طبیعت احتمالاتی متغیرهای اقلیمی از سوی دیگر، موجب عدم قطعیت درجه­بندی تناسب اراضی برای کشت یک گیاه به‌ویژه در شرایط دیم می­شود. برای این منظور در پژوهش حاضر، ابتدا با استفاده از داده­های روزانه بارش و دمای کمینه و بیشینه 33 ایستگاه هواشناسی در استان گلستان، تاریخ مناسب کشت گندم (Triticum aestivum L.) دیم و زمان وقوع مراحل فنولوژیکی مختلف آن برای دوره آماری مشترک 26 ساله تعیین گردید. سپس با برازش توزیع­های احتمالاتی مختلف و انتخاب توزیع منتخب، مقدار این متغیرها در پنج سطح احتمال وقوع 25، 50، 75، 85 و 95 درصد برآورد شد. در ادامه، میانگین دمای هوا، احتمال رخداد دماهای نامطلوب، میزان بارش و نسبت بارش مؤثر به تبخیر- تعرق گندم برای هر یک از مراحل رشد و کل دوره رشد در ایستگاه­های هواشناسی مورد بررسی در سطوح احتمال مختلف محاسبه شد. در نهایت، ضمن تهیه نقشه پهنه­بندی این متغیرها و ویژگی­های ارتفاع، درصد شیب، تیپ اراضی و شوری خاک، با هم‌پوشانی 22 لایه اطلاعاتی برای هر سطح احتمال، پهنه­بندی زراعی- بوم­شناختی اراضی کشاورزی استان گلستان برای کشت گندم دیم در سطوح احتمال مختلف صورت گرفت. نتایج نشان داد که افزایش سطح احتمال وقوع از 25 به 95 درصد به‌دلیل تأخیر در تاریخ کشت مناسب از اواخر پاییز به ابتدای زمستان و تأثیرگذاری آن بر شرایط اقلیمی- محیطی و طول مراحل بعدی رشد گیاه موجب بهبود درجه تناسب اراضی کشاورزی برای کشت گندم دیم از نظر میانگین دمای هوا در مرحله­های گل‌دهی، رسیدگی و کل فصل رشد، احتمال رخداد دمای بیشتر از 14 و کمتر از نه درجه سانتی­گراد به‌ترتیب در مرحله سبز شدن و مرحله­های گل‌دهی و رسیدگی و میزان بارش در مرحله سبز شدن شد، ولی از نظر میانگین دمای هوا در مرحله سبز شدن، احتمال رخداد دمای بیشتر از 25 و 30 درجه سانتی­گراد به‌ترتیب در مرحله گل‌دهی و رسیدگی و میزان بارش و نسبت بارش مؤثر به تبخیر- تعرق پتانسیل در مراحل گل‌دهی، رسیدگی و کل فصل رشد موجب کاهش درجه تناسب گردید. نتایج پهنه­بندی زراعی- بوم­شناختی نشان داد که در سطوح احتمال وقوع 50، 75 و 85 درصد پهنه­های نسبتاً مناسب و مناسب به‌ترتیب بین 56-50 و 50-44 درصد وسعت اراضی کشاورزی را در بر می­گیرد و سطح احتمال وقوع تأثیر معناداری بر پهنه­بندی ندارد، در حالی­که در سطح احتمال وقوع 25 و 95 درصد (به‌ترتیب معادل تاریخ کشت زودهنگام و دیرهنگام) به‌ترتیب حدود 91 و 78 درصد وسعت اراضی کشاورزی استان به‌ترتیب در پهنه مناسب و متوسط قرار گرفت.

کلیدواژه‌ها


عنوان مقاله [English]

Zoning of Golestan Province Agricultural Land for Rainfed Wheat (Triticum aestivum L.) Based on Climatic- Stochastical Analysis

نویسنده [English]

  • Kami Kaboosi
چکیده [English]

Introduction
Stochastical analysis can increase decision-making reliability, meanwhile increasing the flexibility of decisions. The critical role of climatic factors in land zoning on the one hand and the stochastical nature of climatic variables, on the other hand, causes the uncertainty of land suitability grading for plant cultivation, especially in dryland conditions. Golestan province has the third rank among the Iran provinces with about 400,000 hectares of cultivated land and production of more than one million tons of wheat, of which about 57 and 50 percent are allocated to rainfed cultivation, respectively. The present study was conducted to examine changes in various climate variables affecting wheat growth under the influence of different occurrence probabilities and zoning agricultural land in Golestan province for the rainfed wheat cultivation under these conditions.
 
Materials and Methods
 First, dates of planting and occurrence of each phenological stage of rainfed wheat were determined by daily data of precipitation and minimum and maximum temperatures for 33 weather stations in Golestan province in a 26-year typical statistical period. Then, by fitting different probability distribution functions and selecting the best distribution, the values of these variables were estimated at five occurrence probability levels of 25, 50, 75, 85, and 95 percent. Next, the average air temperature, the possibility of occurrence of adverse temperatures, precipitation and ratio of effective precipitation to potential evapotranspiration of wheat for each growth stage and total growth period were calculated for whole weather stations at different occurrence probability levels. Finally, by providing zoning maps of these variables and other features including elevation, land slope, land type, soil salinity and overlaying 22 layers for each occurrence probability level, agro-ecological zoning of agricultural lands of Golestan province for rainfed wheat cultivation at different occurrence probability levels was performed.
 
Results and Discussion
 Results showed that increasing occurrence probability level from 25 to 95 percent due to delaying suitable planting date from late autumn to early winter and its effect on the climatic-environmental conditions and the length of the plant growth stages improved the degree of land suitability grade for rainfed wheat cultivation in terms of mean air temperature in stages of flowering, maturity and total growth season, the occurrence possibility of temperatures higher than 14 and less than 9 °C in germination and flowering and maturity stages, respectively, and the amount of precipitation in the germination stage. Adversely, it resulted in degradation in the degree of land suitability in term of mean air temperature in the germination stage, the occurrence possibility of temperatures higher than 25 and 30 °C in flowering and maturity stages, respectively, and the amount of precipitation and ratio of effective precipitation to potential evapotranspiration in stages of flowering and maturity and the entire season. The results of agro-ecological zoning showed that the extent of suitable and moderate zones was between 50-56 and 44-50 percent of the agricultural land, respectively, for the occurrence probability levels of 50, 75 and 85 percent and the occurrence probability did not have a significant effect on zoning. In comparison, at the occurrence probability levels of 25 and 95 percent (equal to the early and late planting dates, respectively), about 91 and 78 percent of the province's agricultural land was located in a suitable and moderate zone, respectively. These results are accordant with the findings of Hoseini et al. (2018), who showed that the maximum extent of suitable land for cotton cultivation in Southern Khorasan province occurred in the early planting date. Considering the majority of agricultural land of Golestan province is located in the middle strip of the province, most changes of zoning maps by occurrence probability level have also occurred in this region.
 
Conclusion
A low reduction in cultivation risk (increasing the occurrence probability from 25 to 50 percent) significantly degraded the land suitability for rainfed wheat in Golestan province while more reduction in the farming risk (increasing the occurrence probability up to 85 percent) led to no significant effect on land suitability. However, if the minimum risk (95% probability) be selected as a management decision for rainfed wheat farming, the lowest land suitability for rainfed wheat cultivation will occur.

 

کلیدواژه‌ها [English]

  • Agro-ecology
  • Air Temperature
  • Evapotranspiration
  • Land suitability
  • Occurrence probability
  • Precipitation
Ahmadali, K., Hosseini Pajouh, N., and Liaghat, A.M., 2016. Determination of optimal planting date of rainfed wheat in Kurdistan province, Iran. Agronomy Journal (Pajouhesh and Sazandegi) 108: 9-18. (In Persian with English Summary)
Amirikia, F., and Naji Domirani, S., 2017. Land suitability evaluation for dryland wheat production in Fars province based on climatic and physiographic factors and integrated TOPSIS-AHP model in GIS environment. Journal of Applied Research in Field Crops 30(4): 74-92. (In Persian with English Summary)
Anonymous., 2016. Agricultural Statistical Book (2014-2015). Available online: www.maj.ir. (In Persian)
Anonymous., 1999. SMADA for window (stormwater management and design aid). Available online: University of Central Florida.
Baniaghil, A.S., Rahemi Karizki, A., Biabani, A., and Faramarzi, H., 2017. Potential climatic zoning of wheat (Triticum aestivum L.) Golestan province. Journal of Agroecology 9(3): 821-833. (In Persian with English Summary)
Biabani, A., Ahansaz, S., Kamkar, B., and Roumani, A., 2017. Assessment of land suitability of Gorganrood watershed for wheat cultivation by GIS. Research Achievement for Improvement Crop Production 3(1): 83-101. (In Persian with English Summary)
Bidadi, M.J., Kamkar, B., Abdi, O., and Kazemi, H., 2015. Land suitability analysis on rainfed wheat cropping using geospatial information systems (A case study: Qaresoo basin). Journal of Sustainable Agriculture and Production Science 25(1): 131-143. (In Persian with English Summary)
FAO., 1998. Crop Evapotranspiration (Guidelines for Computing Crop Water Requirements). FAO Irrigation and Drainage Paper, Italy.
FAO., 2019. FAOSTA. http://www.fao.org/faostat/en/#home
Hoseini, S.S., Behdani, M.A., and Khashei Siuki, A., 2018. Spatial and temporal zoning of suitable lands for cotton cultivation using analytical hierarchy process (Case study: South Khorasan province). Journal of Agroecology 9(4): 1136-1148. (In Persian with English Summary)
Kaboosi, K., and Majidi, O., 2019. Determination and zoning of suitable planting date of rainfed wheat in Golestan province based on different levels of occurrence probability of autumn rainfall. Journal of Agroecology 11(1): 217-229. (In Persian with English Summary)
Kaboosi, K., and Majidi, O., 2017 a. Agro-ecological zoning of rainfed wheat in Golestan province based on meteorology, agronomy, soil and land properties. Journal of Agroecology 7(2): 134-154. (In Persian with English Summary)
Kaboosi, K., and Majidi, O., 2017 b. Zoning of planting and harvesting dates and length of growth stages of rainfed wheat based on precipitation and temperature data in Golestan province. Iranian Journal of Dryland Agriculture 6(1): 103-120. (In Persian with English Summary)
Kaviani, M.R., Hosseini Abri, S.H., and Asadi Broujeny, E., 2002. Probability of occurrence and return period of minimal temperature in almond orchards at Semnan region during March, April and May. Journal of Agricultural Sciences and Natural Resources 9(3): 49-57. (In Persian with English Summary)
Kazemi, H., Tahmasebi Sarvestani, H., Kamkar, B., Shataei, S., and Sadeghi, S., 2013. Agro-ecological zoning of Golestan province lands for soybean cultivation using geographical information system (GIS). Journal of Sustainable Agriculture and Production Science 23(4): 21-40. (In Persian with English Summary)
Khoshal Dastjerdi, J., Nazari, A., Ghangharmeh, A., and Fallahi, H.A., 2015. Predicting isometropia- rainfall in dry wheat implantation and cultivation in Gonbad Kavoos province. Geographical Planning of Space 5(16): 169-184. (In Persian with English Summary)
Khosravi, R., Hemami, M.R., and Malekian, M., 2014. Comparison of geostatistical methods to determine the best bioclimatic data interpolation method for modelling species distribution in central Iran. Iranian Journal of Applied Ecology 3(8): 55-68. (In Persian with English Summary)
Mehdizadeh, S., Behmanesh, J., and Nikbakht, J., 2011. Estimation of reference evapotranspiration with various occurrence probability levels (Case study: Urmia). Water and Soil Science 20(4): 171-183. (In Persian with English Summary)
Mohammadi, H., 2005. The determining suitable dry farming wheat time in Ilam provience. Geographical Research. 37(51): 15-31. (In Persian with English Summary)
Nasrollahi, N., Kazemi, H., Kamkar, B., and Sadeghi, S., 2016. Agroecological evaluation of Aq-Qala township (Golestan province) for Dryland wheat cultivation using geographical information system (GIS). Journal of Applied Field Crops Research 29(1): 83-94. (In Persian with English Summary)
Nekahi, M.Z., Soltani, A., Siahmarguee, A., and Bagherani, N., 2014. Yield gap associated with crop management in wheat (Case study: Golestan province- Bandargaz). Crop Production 7(2): 135-156. (In Persian with English Summary)
Nikbakht, J., and Mir Latifi, S.M., 2002. Effects of ET0 computing method, probability level and length of peak water requirement period on daily reference evapotranspiration. Iranian Journal of Soil and Waters Sciences 16(2): 222-230. (In Persian with English Summary)
Noohi, K., 2005. Rainfall analysis of Karaj for determination of rainfed wheat sowing date. Nivar 58: 95-103. (In Persian with English Summary)
Rahimi, J., Bazrafshan, J., and Khalili, A., 2013. A comparative study on empirical methods for estimating effective rainfall for rainfed wheat crop in different climates of Iran. Physical Geography Research 45(3): 31-46. (In Persian with English Summary)
Sharifi Bonab, S.S., Nazemi, A.H., Ashraf Sadraddini, A., Fakheri Fard, A., and Salmasi, F., 2015. Estimation of irrigation water requirement using probability distribution functions. Iranian Journal of Irrigation and Drainage 5(9): 720-730. (In Persian with English Summary)
Sobhani, B., Ganji, M., and Goldoust, A., 2017. Determination and investigation about beginning and end dates of early and late freezes and possibility of its continuity, intensity and succession in Ardabil province. Physical Geography Research Quarterly 49(1): 39-53. (In Persian with English Summary)
Sys, I.C., Van Ranst, E., and Debaveye, J., 1991. Land evaluation- part I: Principle in land evaluation and crop production calculations. General Administration for Development Cooperation, Agricultural Publication No. 7, Brussels, Belgium, 274 pp.
Torabi, B., Soltani, A., Galeshi, S., and Zeinali, E., 2012. Documenting the process of wheat production in Gorgan. Journal of Plant Production 19(4): 19-42. (In Persian with English Summary)
Yousefi Moghaddam, R., Khoramdel, S., Bannayan Aval, M., and Nassiri Mahallati, M., 2018. Comparison of old and new dryland wheat cultivars in response to different planting dates. Applied Research in Field Crops 31(2): 46-72. (In Persian with English Summary)
Ziaee, A.R., Kamgar-Haghighi, A.A., Sepaskhah, A.R., and Ranjbar, S., 2006. Development of Fars province probable minimum temperature atlas using meteorological data. Journal of Water and Soil Science (Journal of Science and Technology of Agriculture and Natural Resources) 10(3): 13-27. (In Persian with English Summary)