تحليل ارتباط بين تغييرپذيري‌هاي اقليم، عملكرد و ريسك توليد محصولات كشاورزي؛ مطالعه گندم ديم استان فارس

The Investigation of Climate Change Effect on Agricultural Production Risk; the Case of Wheat in Fars Province

اين بررسي با هدف پاسخگويي به اين پرسش بود كه آيا پديده تغييرپذيري اقليم افزون بر عملكرد محصولات كشاورزي بر خطرپذيري (ريسك) عملكرد نيز تاثيرگذار است يا خير، طرح ­ريزي شد. بدين منظور محصول گندم ديم به عنوان يك كالاي اساسي و نيز تأثيرپذير از اقليم در استان فارس گزينش شد. با استفاده از تابع توليد تصادفي جاست و پاپ و رهيافت كمينه مربعات تعميم­ يافته قابل دسترس، اثرگذاري متغيرهاي اقليمي و غيراقليمي در شش شهرستان آباده، اقليد، مرودشت، شيراز، لارستان و لامرد در سال­هاي 1374-1395 بر ميانگين و ريسك عملكرد ارزيابي شد. نتايج نشان داد كه بارندگي به عنوان يكي از عامل­ هاي اصلي پديده تغيير اقليم رابطه ­ي مستقيم با عملكرد گندم ديم دارد، طوريكه اين متغير 61/1 درصد از تغييرپذيري عملكرد را پيش­بيني كرده ­است. افزون بر اين، بارندگي و دما به عنوان نهاده ­هاي ريسك­ كاهنده در توليد محصول گندم ديم استان فارس اثرگذار بوده ­اند. در نهايت، تغييراقليم، شرايطي را فراهم مي­آورد تا ميانگين دما توانمندي لازم براي جبران زيان ناشي از كاهش بارندگي را دارا باشد. با توجه به يافته­ هاي پژوهش، تاكيد مي­ شود تا سياست­هاي لازم، تامين و استفاده از بذرهاي گندم مقاوم به گرما و مكانيزه كردن كشت، براي سازگاري با تغييراقليم صورت پذيرد.

Introduction Wheat is one of the main strategic agricultural product. It is common human food source in developing countries such as Iran. Therefore, wheat production has indispensable role on food security in Iran. More than half cereals’ farms have been dedicated to wheat farming in Iran. This study intents to investigate the raised question “how does climate change affect wheat yield?” particularly in rain-fed wheat’s farms as a sensitive crop to climatic aspects as the study purpose. Materials and Method Random function of the Just and Pope (1978, 1979) base on Feasible Generalize List Square approach (FGLS) was utilized to examine the role of climatic and non-climatic factors on variance of rain-fed wheat yield in six regions including Abadeh, Eqlid, Marvdasht, Shiraz, Larestan and Lamerd through a period of 22 years (1995_2015). The data of temperature and precipitation were predicted through four-time period contains 2011-2030, 2031-2050, 2051-2070, and 2071-2090. Four scenarios including RCP 4.5 and RCP 8.5 relying on GFDL-CM3 model were developed to forecast climatic variables. Finally yield and its risk were analyzed. Results and discussion The results demonstrated precipitation as one of the most important factors with significance positive effect on rain-fed wheat’s yield, it predicted 1.61 percent of variation of rain-fed wheat’s yield. Moreover, the precipitation and temperature were found as reducing risk inputs on rain-fed wheat’s yield of Fars province. Findings illustrated that climate change will change temperature to be able to compensate loss due to reduced precipitation effect, because of both positive effect of temperature and precipitation. Suggestion According to study findings, some suggestions were presented to policy makers in designing mitigation and adaptation strategies for rain-fed wheat’s farmers in response to climate change. Our suggestions contain using heat resistant seed and using mechanical machines during wheat cultivation in order to cope negative effects of seed and labor on yield in recently years. JEL Classification: C23, C53, C87, Q57