The relationship between rice yield in East China and ENSO
华东地区水稻产量与厄尔尼诺-南方涛动的关系

摘要

根据1951-2022年华东地区六省一市的年平均水稻产量、同期33个气象站的月平均气温和月降水量以及同期ENSO指数（ONI）资料，以相对气象产量作为研究对象，通过连续小波变换对华东地区水稻相对气象产量（Y）、平均气温、降水量距平（ΔT、ΔR）以及ENSO指数（ONI）的时频变化特征进行多尺度分析，并在此基础上采用交叉小波变换方法分析华东地区气候变化对水稻产量的影响，探讨水稻产量与ENSO事件之间的相关关系。结果表明：（1）Y与ΔT存在4a、8a和16～28a左右尺度的明显周期振荡；与ΔR存在8a、12a和16～28a尺度的明显周期振荡；与ONI存在2～4a和8a尺度的明显周期变化。（2）Y与ΔT在4～8a尺度周期上表现为弱的正相关，在16a尺度上表现为负相关；与ΔR在12a尺度上表现为负相关，在22a尺度上表现为正相关。Y与气温的正相关性不明显，气温异常偏高不利于产量的增加；降水的相关性则表明在干旱少雨的年份水稻减产，同时降水过多易发生洪涝灾害也会造成水稻减产。（3）Y与Nino3.4区海温多年平均滑动距平（ONI）在12a尺度周期上表现为正相关，在22a尺度上表现为负相关；在各异的时频窗口上，华东地区水稻相对气象产量与Nino3.4区海温的相关变化具有多层次的特征。

Abstract

Based on the annual average rice yield, monthly average temperature and precipitation from 33 meteorological stations, as well as ENSO index (ONI) data from 1951 to 2022 in six provinces and one municipality of East China, relative meteorological yield was taken as the research object. Continuous wavelet transform was employed to conduct multiscaling analysis on the time-frequency characteristics of East China's rice relative meteorological yield (Y), average temperature, precipitation anomaly (ΔT, ΔR), and ENSO index (ONI). On this basis, cross-wavelet transform was used to analyze the impact of climate change on rice yield in East China, exploring the correlation between rice yield and ENSO events. The results indicate: (1) Y exhibits significant periodic oscillations with ΔT at approximately 4a, 8a, and 16–28a scales; with ΔR at 8a, 12a, and 16–28a scales; and with ONI at 2–4a and 8a scales. (2) Y shows weak positive correlation with ΔT at 4–8a scales and negative correlation at 16a scales; negative correlation with ΔR at 12a scales and positive correlation at 22a scales. The positive correlation between Y and temperature is not significant, with abnormally high temperatures being unfavorable for yield increase. Precipitation correlation suggests reduced rice yield in drought years with insufficient rainfall, while excessive precipitation leading to floods also causes yield decline. (3) Y and ONI (sliding anomaly of Nino3.4 sea surface temperature) exhibit positive correlation at 12a scales and negative correlation at 22a scales. Across various time-frequency windows, the correlation changes between East China's rice relative meteorological yield and Nino3.4 sea surface temperature display multi-layered characteristics.