关键词: 连阴雨, 时空变化, 多尺度, 小波分析, 产量

Abstract: Continuous rain is a major factor affecting the yield and quality of grape in Shaanxi Province. Developing a continuous rain index for vineyard and investigating its spatiotemporal characteristics and impacts on the grape yield were important for disaster prevention and mitigation. For this purpose, we used statistical methods including Mann-Kendall (M-K) trend test, abrupt detection, bivariate and multivariate wavelet analysis to analyze the meteorological data from 1961-2018 and grape yield data from 1978-2018 in Shaanxi Province. The results showed that the yield per hectare, planting area and total yield of grape were increased significantly from 3166 to 15604 kg·hm^-2, 600 to 46680 hm², and 1.9 to 728.4 thousand tons from 1978 to 2018, respectively. 2009, 2011, 2014 and 2015 were typical years with continuous rain disaster for vineyard. Spatially, the frequency, cumulative time and cumulative rainfall of continuous rain, light continuous rain and severe continuous rain for vineyard increased from the north to the south of Shaanxi. Temporally, the cumulative time, cumulative rainfall and frequency of continuous rain and severe continuous rain for vineyard showed a decreasing trend, while the cumulative time, cumulative rainfall and frequency of light continuous rain for vineyard showed an increasing trend from 1961 to 2018. The meteorological yield of grape showed a dominating period of 8-10 years from 1978 to 2007 and a dominating period of 4-6 years after 2008. The meteorological yield of grape was significantly correlated with continuous rain.

Key words: continuous rain, spatiotemporal characteristics, multi-time scales, wavelet analysis, yield.