Correlation of Teleconnection Patterns with Temperature Series and Productivity of Barberry in Ghaenat Basin

Barberry is one of the healthy and organic products of the country. This product can make an important contribution to the export of the country's agricultural sector with systematic planning and infrastructure creation. Barberry is one of the crops that require little water and is recommended for optimal use of water and soil resources and replacement with plants with high water consumption. Seedless barberry is one of the valuable native plants that is grown only in Iran as a garden product. Due to its high resistance in the conditions of water shortage and desert weather, it is a strategic product for many people in desert areas and especially in South Khorasan. This agricultural product is one of the strategic agricultural products in the province and Iran and plays a high role in creating wealth for the livelihood of villagers. Therefore, investigating the characteristics and growth conditions of this product is of great importance. One of the things that should be studied for this product is the effect of climatic parameters and especially temperature changes on the growth and yield of this type of plant.

To conduct this research, the monthly data of minimum temperature, maximum temperature, average temperature, absolute maximum temperature and absolute minimum temperature of Qain and Gonabad stations during the period of 1989-2021 have been used. Also, the data of 16 teleconnection patterns at the same time as the mentioned period were used to measure the relationship between the studied parameters and teleconnection patterns. These patterns were extracted and used from the Noa site. Correlation and linear regression tests will be used in order to investigate the relationship between teleconnection patterns and studied temperature parameters and the amount of barberry production and yield. In this way, the existence of correlation and connection between the studied parameters will be identified.

The results of the correlation between the average temperature of the studied basin and teleconnection patterns showed that in Qain station, the average temperature parameter is more correlated with TNA, AMO, and AMOS patterns. The correlations occurred mostly in the second half of the year during the months of June to December, and in the first half of the year, almost all indicators were without correlation. In the minimum temperature parameter, TNA, AMO, NTA, AMOS have shown more correlation than other indices. In this parameter, more correlations have been observed in the second half of the year. In terms of time, in the two months of September and November, more indicators have been correlated with the minimum temperature. In the maximum temperature parameter, EA.WR, NTA and AMOS indicators have shown more correlation with the maximum temperature of Qain than other indicators. The correlations occurred mostly during the months of March to December. The NAO, Nino1.2, and TNI indices did not show any correlation with the maximum temperature of Qain in any of the months. The absolute maximum temperature of Qain station in July has shown a correlation with the teleconnection indices. In the months of June, September to December, it has not shown any correlation with any of the link patterns. The absolute minimum temperature of Qain station in January has shown more correlation with the link patterns than other months. AMOS, AMO and NTA models have more correlation with this parameter than other models. Correlation between teleconnection indices and barberry production and yield showed that the Nino3 index had a 99% significant inverse correlation with the barberry production and the AO index had an inverse correlation with the barberry yield at a 95% significance level. The correlation between the studied temperature parameters and the amount of barberry production and yield during the studied period showed that there was no correlation between them.

In total, the results of the obtained correlations indicate that the correlations occurred mostly in the second half of the year. Also, respectively, AMOS, AMO and TNA indices have been correlated more than other indices with the studied temperature series. Nino indices were also uncorrelated in almost all temperature series in both Qain and Gonabad stations. In terms of time, average temperature, minimum temperature and maximum temperature in the months of July and October and the absolute maximum temperature in July more than other months have shown a correlation with the link indices. The absolute minimum temperature at Qain station in January and October and at Gonabad station in January and September were more correlated with the teleconnection indices. The results of the analysis of variance also showed that two patterns, AMO and AMOS, had more influence on the studied temperature series than other patterns. According to the results of the correlation between teleconnection patterns and barberry crop efficiency, the Nino3 index has shown an inverse correlation with the barberry production rate at a 99% significance level, and the AO index has shown an inverse correlation with the crop performance at a 95% significance level. According to these results, it can be stated that the indices related to the Atlantic Ocean have a direct correlation and a greater impact on the temperature series of the studied area. These patterns affect Iran through the influence on the Mediterranean and Azores subtropical high pressure systems. The indices related to the Pacific Ocean have also been inversely correlated with the yield of the crop and the tropical Pacific indices with the amount of barberry production.