Evolution trends of cold dew wind over the recent 40 years and its impact on late rice in Nanning City
[Objective]Three aspects including the spatial and temporal distribution characteristics, the evolution trends of cold dew wind, and its impact on late rice production were studied so as to provide references for fending off cold dew wind and late rice production planning in Nanning.[Method]Tendency rate analysis and sliding t-test analysis were applied to study the above-mentioned three aspects using the average daily temperature statistics during 1970-2011 from eight ground meteorological stations.[Result]The occurrence frequency of cold dew wind in northeast Nanning was higher than other regions.While the overall occurrence frequency of cold dew wind in Nanning reduced from the beginning of the 21st century, mild cold dew wind showed a slightly increasing trend, moderate cold dew wind showed slowly weakening trend and severe cold dew wind showed significantly reducing trend.Compared with ten years before, moderate and severe cold dew wind occurred in Nanning 3 to 6 days earlier, while mild cold dew wind occurrence time was 5 days later.The duration of cold dew wind had no significant relationship with late rice production in Nanning, whereas it had significantly positive correlation with sterile grain rate.[Conclusion]In northeast Nanning with high cold dew wind occurrence frequency, planting areas of late rice should be decreased appropriately, and the varieties with strong stress resistance should be chosen to plant to reduce the influence of cold dew wind.The sowing time of earlier and late rice should be properly arranged according to the characters of cold dew wind in Nanning.The peasants short of labor with large rice-planting area should plant early rice earlier and late rice later; and the farmers with ample labor should plant moderate and late rice later, planting early and late rice later was not inadvisable.
国家科技期刊平台
NSTL
万方数据
维普
