Liu Hong-Bin, Gou Yu, Wang Hong-Ye, Li Hong-Mei, Wu Wei
College of Resources and Environment, Southwest University, Chongqing, 400716, China.
Int J Biometeorol. 2014 Aug;58(6):1021-30. doi: 10.1007/s00484-013-0686-3. Epub 2013 Jun 5.
Knowledge of variability in climatic variables changes and its impact on crop yields is important for farmers and policy makers, especially in southwestern China where rainfed agriculture is dominant. In the current study, six climatic parameters (mean temperature, rainfall, relative humidity, sunshine hours, temperature difference, and rainy days) and aggregated yields of three main crops (rice: Oryza sativa L., oilseed rape: Brassica napus L., and tobacco: Nicotiana tabacum L.) during 1985-2010 were collected and analyzed for Chongqing-a large agricultural municipality of China. Climatic variables changes were detected by Mann-Kendall test. Increased mean temperature and temperature difference and decreased relative humidity were found in annual and oilseed rape growth time series (P<0.05). Increased sunshine hours were observed during the oilseed rape growth period (P<0.05). Rainy days decreased slightly in annual and oilseed rape growth time series (P<0.10). Correlation analysis showed that yields of all three crops could benefit from changes in climatic variables in this region. Yield of rice increased with rainfall (P<0.10). Yield of oilseed rape increased with mean temperature and temperature difference but decreased with relative humidity (P<0.01). Tobacco yield increased with mean temperature (P<0.05). Path analysis provided additional information about the importance and contribution paths of climatic variables to crop yields. Temperature difference and sunshine hours had higher direct and indirect effects via other climatic variables on yields of rice and tobacco. Mean temperature, relative humidity, rainy days, and temperature difference had higher direct and indirect effects via others on yield of oilseed rape.
了解气候变量变化的变异性及其对作物产量的影响，对农民和政策制定者而言至关重要，在中国西南部以雨养农业为主的地区尤为如此。在本研究中，收集并分析了中国大型农业直辖市重庆1985 - 2010年期间的六个气候参数（平均温度、降雨量、相对湿度、日照时数、温差和雨日）以及三种主要作物（水稻：Oryza sativa L.、油菜：Brassica napus L.和烟草：Nicotiana tabacum L.）的总产量。通过曼-肯德尔检验检测气候变量变化。在年尺度和油菜生长时间序列中发现平均温度和温差增加，相对湿度降低（P<0.05）。在油菜生长期间观察到日照时数增加（P<0.05）。在年尺度和油菜生长时间序列中雨日略有减少（P<0.10）。相关性分析表明，该地区所有三种作物的产量都可能受益于气候变量的变化。水稻产量随降雨量增加（P<0.10）。油菜产量随平均温度和温差增加，但随相对湿度降低（P<0.01）。烟草产量随平均温度增加（P<0.05）。通径分析提供了关于气候变量对作物产量的重要性和贡献路径的更多信息。温差和日照时数通过其他气候变量对水稻和烟草产量具有更高的直接和间接影响。平均温度、相对湿度、雨日和温差通过其他因素对油菜产量具有更高的直接和间接影响。
