An investigation of relation between CO2 emissions and yield of tea production in Guilan province of Iran

This paper examines the CO2 emissions patterns and the relationship between CO2 input and yield for tea production in Lahijan city of Guilan province. Data from 30 farmers were collected using a face-to-face questionnaire method. The results showed that the average of total CO2 emissions in tea production was 935.98 kgCO2eq. ha-1 where the nitrogen with about (26.32%) and diesel fuel with about (26.32%) were the major CO2 emitter, respectively. Based on three farms size level results, the medium and small farms had the best and worst condition from CO2 emissions and tea yield point of view. The CO2 ratio of small, medium, large and total farms was computed as 0.113, 0.079, 0.105 and 0.089 kgCO2eq. kg-1, respectively. In this study, the Cobb-Douglass production function was applied for modeling of CO2 inputs on tea yield. Econometric assessment results revealed that the CO2 inputs of phosphate and nitrogen had significant influence on the yield. The impact of phosphate (-2.60) and nitrogen (2.50) were found at the highest among the other input parameters in decreasing and increasing of yield, respectively. Sensitivity analysis indicated that the MPP value of CO2 inputs was between -24.17 and 66.91. Also the MPP value of nitrogen was the highest among all CO2 emitter inputs.