Impacts of pricipitation and temperature variability on rice production in Mitole Epa Chikwawa

Background: Rainfall and temperature variability are a threat to sustainable agricultural production in Malawi. Main crops which include rice are highly affected due to climate variability since this crop is grown during wet season. A study was therefore conducted in one EPA named Mitole in Chikwawa district in southern Malawi to determine the impacts of precipitation and temperature variability on rice production. Method: Secondary data of climate variables and rice data was used for a period of 16 years which was obtained from Department of Climate Change and Meteorological Services (DCCMS) in Blantyre and Mitole EPA in Chikwawa respectively. Before data analysis data quality control was done where outliers were manually corrected and also errors were corrected using homogeneity test in which single mass curve for each data were plotted. In data analyses; excel and R was used to do trend analysis. Mann Kendall test was used to test if there were significant trend of data or not. To determine the relationship between climate parameters and rice production correlation analysis tested. Regression analysis was also used to predict the results if the climate variables keep varying. Result: The results showed that only minimum temperature had a negative significant trend and other variables had trends which were not significant. Correlation analysis showed non-significant relationship between climate parameters and rice production and also the results of regression analysis had non-significant relation therefore there was enough evidence to predict the results in future. Conclusion: Since the results did not provide enough evidence that climate variables specifically rainfall and temperature affect rice production in the area, it was recommended that more research must be done to discover the way farmers must follow to maximize the production.

背景：降雨与气温变异性是马拉维可持续农业生产面临的显著威胁。包括水稻在内的当地主要作物受气候变异性影响严重，因该作物的种植周期恰好处于雨季。为此，研究团队在马拉维南部奇夸瓦区名为米托莱的农业推广规划区（Extension Planning Area, EPA）开展了本研究，旨在探明降水与气温变异性对水稻生产的影响。
方法：本研究采用了16年时长的气候变量与水稻生产二手数据，数据分别取自布兰太尔的气候变化与气象服务部（Department of Climate Change and Meteorological Services, DCCMS）以及奇夸瓦区的米托莱EPA。数据分析前，研究团队开展了数据质量管控工作：对异常值进行手动修正，并通过齐性检验修正数据误差，该检验会绘制各数据集的单质量曲线。数据分析阶段，研究人员采用Excel与R语言开展趋势分析，并通过曼-肯德尔检验（Mann Kendall test）判断数据是否存在显著趋势。为探究气候参数与水稻生产之间的关联，研究开展了相关性分析；此外还采用回归分析，以预测气候变量持续变化时的水稻生产结果。
结果：研究结果显示，仅最低气温呈现显著负向趋势，其余变量的趋势均不显著。相关性分析结果表明，气候参数与水稻生产之间无显著关联；回归分析结果同样显示二者无显著相关关系，因此有足够依据对未来的水稻生产结果进行预测。
结论：鉴于本研究结果未提供足够证据证明该区域的气候变量（尤其是降雨与气温）会对水稻生产产生影响，因此建议开展更多相关研究，以探索农户可遵循的水稻生产最大化路径。