Climate Characters of Summer Drought in Mountain City and the Effect on Flowers and Trees

[Objective] The aim was to provide references for development of industries engaging in flowers and trees in Beipei area in Chongqing. [Method] The occurring trend, intensity trend of summer drought, relationship of intensity with rainfall and extremely highest temperature, occurring trend during initial period of summer drought and the effects in mountain cities were analyzed, based on information on lasting period, rainfall, average temperature, extremely highest temperature of sum- mer drought in Beipei area in mountain cities during 1981-2010 and, growth condi- tion and phenological phenomena of Michelia champaca during 2005-2007. [Result] The occurring probability of summer drought in mountain cities was 57% and the probabilities of light, moderate, heavy and extreme drought were 30%, 10%, 7% and 10%; intensity of summer drought was none of linear relation with rainfall and ex- tremely highest temperature. In summer drought, daily average rainfall was less than 0.9 ram; extremely highest temperature was 35.0-45.0 ℃ with probability at 30%; initial period of summer drought was from later June to middle August and of extreme drought was later June-later July; the ending period was early September. During drought, when the extremely highest temperature （〉35.0 ℃） occurred in three days within a Hou, flowers and trees were affected by the hot drought and when the extreme temperature （〉40.0 ℃） occurred in three days within a Hou, the plants were seriously affected. [Conclusion] Based on characters of summer drought, pre- cautions can be taken to reduce effects of summer drought on flowers and trees with the help of weather forecast.

Climatic Characteristics of Extreme Cold and Frost Disaster and the Effects on Flowers and Trees in Mountain City in 2010

[Objective] The aim was to explore climatic characteristics of cold and frost disaster and the effects on flowers and trees in mountain city in 2010. [Method] Extremism of cold and frost disaster in temperature and lasting period, and the effects on flowers and trees in 2010 were researched based on information of average ten-day temperatures and extreme lowest temperature in 1951-2010 and Michelia alba DC. growth in a Hou in 2008-2010, as per statistical analysis technique. [Result] Cold and frost disaster in winter of 2010 proved the longest in lasting period, lowest in average temperature, and most serious for flowers and trees, resulting in serious loss of flowers and trees in Beibei area. [Conclusion] Countermeasures in the research would reduce owners’ loss in flowers and trees.