Rainfall and temperature are essential climate parameters that determine crop yield variability at a regional level. The purpose of this study is to analyse the impacts of climate variability on the Kharif rice crop in the Punjab regions, Pakistan for the period of 1979–2018. Skewness and kurtosis, standardization, and Mann–Kendall methods were used to measure the effects of climate variability on Kharif rice yield over the Punjab regions, Pakistan. As compared to other regions, high variability in rice yield is found in the Sargodha region. Results revealed that high maximum and minimum temperatures were noticed in all investigated regions of Punjab. More variation in minimum temperature is detected than the maximum temperature in the Central region. The regions in Southern and Western Punjab were mostly influenced by maximum temperature. Mean temperature shows a significant negative relationship to rice yield during a vegetative phase in the Gujranwala and Rawalpindi regions. The maximum temperature has a negative significant effect on the plant establishment resulting in a reduction in the number of rice plants during the tillering and stem elongates stages in Bahawalpur and Sargodha regions. In the Gujranwala and Multan regions, high maximum temperature increases the floral initiation in the rice plant which reduces the rice grain weight in the heading and flowering stages. The minimum temperature declares a significant negative effect on the Kharif yield of rice in the Gujranwala, Faisalabad, and Multan zones during the re-plantation stage. Rainfall has a significant positive impact on rice yield during the re-plantation and tillering stages in the Lahore, Sargodha, and D.G. Khan regions, respectively. In other regions, rainfall indicates an insignificant effect in the re-plantation stage. Overall, rainfall indicates significant effects in re-plantation and tillering stages in the Lahore, Sargodha, and D.G. Khan zones. The outcomes of the research indicate how the regional variability in rainfall and temperature affects Kharif rice yield in Punjab, Pakistan.

中文翻译：

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分析气候变化对巴基斯坦旁遮普省 Kharif 水稻产量的影响

降雨和温度是决定区域层面作物产量变异性的重要气候参数。本研究的目的是分析 1979-2018 年期间气候变化对巴基斯坦旁遮普地区Kharif水稻作物的影响。偏度和峰度、标准化和 Mann-Kendall 方法用于测量气候变率对Kharif的影响巴基斯坦旁遮普地区的水稻产量。与其他地区相比，Sargodha 地区的水稻产量差异很大。结果表明，在旁遮普邦的所有调查地区都发现了最高和最低温度。检测到的最低温度变化大于中部地区的最高温度。南部和西部旁遮普地区主要受最高温度的影响。在古吉兰瓦拉和拉瓦尔品第地区，平均温度与营养阶段的水稻产量呈显着负相关。最高温度对植物的建立有显着的负面影响，导致在 Bahawalpur 和 Sargodha 地区分蘖和茎伸长阶段水稻植株数量减少。在 Gujranwala 和 Multan 地区，较高的最高温度会增加水稻植株的开花期，从而降低抽穗期和开花期的水稻粒重。最低温度宣布了显着的负面影响Gujranwala、费萨拉巴德和木尔坦地区在重新种植阶段的水稻产量。在拉合尔、萨戈达和 DG Khan 地区，降雨分别对重新种植和分蘖阶段的水稻产量产生了显着的积极影响。在其他地区，降雨表明重新种植阶段的影响微不足道。总体而言，降雨表明拉合尔、萨戈达和 DG Khan 地区的重新种植和分蘖阶段有显着影响。研究结果表明降雨和温度的区域变化如何影响巴基斯坦旁遮普省的Kharif水稻产量。