عنوان مقاله [English]
Introduction: One of the most important human issues in the world, is the production of more food for the world's growing population. The climate of each region is very important in the agricultural sector and the amount of its production. Iran is one of the world's date-producing countries, which ranks second in the world in terms of date production and exports. This plant has 200 genera and four thousand species, each of which has the ability to adapt to a region of arid regions and can have the highest production and economic efficiency in its proper place. . It is a monocotyledonous plant from the Palmaceae family that needs at least 10 degrees Celsius for continued growth. At temperatures below 10 degrees Celsius, growth will stop and temperatures below 4 degrees Celsius will encounter cold stress. This plant is sensitive to environmental conditions and is not able to live in a qualitative and quantitative way in all hot and dry regions. On the other hand, the palm tree is a plant that lives up to several hundred years and some of its varieties bear fruit up to 200 years old, but their useful and economical life is on average about 50 years. It is noteworthy that this tree did not produce an economic crop until ten years ago. Dates have an important role in currency exchange, job creation, food security and strengthening global competitiveness by providing income from non-oil exports. Therefore, the construction of a palm tree is a risky long-term investment in the country. Dates have different varieties, each capable of adapting to a region of arid regions and can produce the most production and economic efficiency in its proper location. Global warming, its impact on different regions of the Earth in the future, and the response of the living creatures of these regions in the last century, have led planners and scientists of many disciplines, especially climatology researchers, and in particular agricultural climatologists to understand climate conditions and design long-lived sustainable plants that can survive in future environmental conditions and have good economic returns, design programs and awareness algorithms.
Methodology: One of the best is the maximum entropy model (MaxEnt). By applying this algorithm, it can be predicted how the species will exist in different regions based on the presence of the species. The present study was conducted by field method, descriptive and library statistics. The data used include: WordClim site data (bioclimatic variables), presence data of two cultivars of date palm, Gantar and Halawi, daily meteorological data, elevation and land slope based on suitable land slope for palm tree cultivation, high and low temperatures and phonological data. CCSM4 model with quadratic scenarios of 2.6, 4.5, 6.0 and 8.5 was used to predict and estimate different regions of the country in terms of talent for cultivation for two selected date varieties. Due to the higher value of AUC in Scenario 4.5, this scenario was considered as the selected scenario. This study is different from previous studies using CCSM4 climatic model, new diffusion scenarios (RCP) and prediction of date distribution with respect to its cultivars, while previous studies on prediction of date distribution have not paid any attention to it.
Result: The results showed that the distribution and cultivation area of Gantar and Halawi are different and in the future the suitable area of cultivation of Gantar cultivar will decrease and suitable area of cultivation of Halawi cultivar will increase. Jacknife test showed that the model was successful in predicting the potential of cultivation area based on the AUC criterion and temperature-related biological variables (Bio 1, Bio 6, Bio 8 and Bio 10) had the greatest impact on the distribution modeling of cultivars. Therefore, with the rising temperature, parts of the country, especially the foothills of the plains, become more susceptible to cultivation. So that at the present time, when the maximum height for the optimal growth of cultivars is about 700 meters, in the coming decades it will reach about 1200 meters.
At present, Iranshahr city in Sistan and Baluchestan province has the most desirable area of cultivation of Gantar and Halawi cultivar. But in the next decade, the most desirable area of cultivation will be for Gontardar cultivar in Ahvaz city and for Halawi cultivar in Jask city. It was also found that using WorldClim site data for perennial and especially long-lived plants was not sufficient. Because in these data, high and low temperatures that can destroy the plant during its life or shorten its life and reduce the economic fruit of cultivation are not included, and of course gardening and fruit trees are a long-term investment. The risk of investing should not be increased.
AUC: area under the receiver operating curve