茶树生长季内云雾变化特征及可能影响

基于气候变暖背景下贵州省茶树生长季内农业气候资源发生了明显变化和云雾是影响茶叶品质的关键气象因子这一科学事实,利用贵州省1961—2010年81个气象台站的地面观测资料,对贵州省不同茶季(春、夏、秋)内云雾的时空变化特征进行了分析。研究结果表明：研究区域春茶季总云量与雾日数百分比的分布特征均表现为由东南向西北减少,夏茶季总云量呈由东南向西北增加,而秋茶季总云量呈由西北向东南递减的趋势；夏茶季总云量最大,其次分别为春茶季和秋茶季,三者的地区间差异均较小；1961—2010年,春、夏、秋茶季总云量均呈减少趋势,减幅最大的是秋茶季(-1.1%/10a),其次分别为夏茶季(-0.5%/10a)和春茶季(-0.17%/10a)。秋茶季雾日数百分比最大,其次分别为春茶季和夏茶季,三者的地区间差异均较大；1961—2010年,春、夏和秋茶季雾日数百分比均呈增加趋势,三者的气候倾向率分别为5.1%/10a、6.9%/10a和7.2%/10a。研究区域茶树生长季内总云量的减少和雾日数的增加,将对贵州省茶树的品种选择、结构调整、茶叶产量和品质等产生相应的影响。

Variation characteristics and possible effect of cloud and fog in growth period of tea plants

Based on the scientific fact that climate resources and agricultural climate resources changed significantly and cloud and fog is the key meteorological factors that influences the quality of tea during tea growing period under the background of climate warming, the temporal and spatial variation of cloud and fog during different tea growing period (spring, summer, autumn) are analyzed by using the ground observation data from 81 meteorological stations from 1961 to 2010 in Guizhou Province. The results indicate that, the distribution of total cloud amount and percentage of the number of fog days in the study area showed a reducing trend from southeast to northwest during spring tea period, the total cloud amount was increased from the southeast to the northwest during summer tea period, while the total cloud amount during autumn tea period was decreasing from the northwest to southeast; The total cloud amount in summer tea period accounts for most in tea growing period, followed by spring tea and autumn tea, and the difference between the regions was generally smaller in these three period; The average of total cloud amount in spring, summer and autumn period all showed a decreasing trend form 1961 to 2010, the biggest decrease period was in autumn tea (-1.1% / 10a), followed by the summer tea (-0.5% / 10a) and spring tea (-0.17% / 10a).The largest percentage of the number of fog days was in autumn tea period, followed by spring and summer tea period, and the regional differences were larger in these three period. The percentage of the number of fog days showed an increasing trend for spring tea, summer tea, autumn tea, and winter tea, the climate trend rate was 5.1% /10a, 6.9%/10a and 7.2%/10a, respectively. Decrease of total cloud amount and the increase of the fog days during tea growing period in the study area will have a corresponding impact on variety screening, structural adjustment, as well as the tea yield and quality etc.