| Based on beginning dates of 10℃ temperature in 39 stations on Loess Plateau of Gansu from 1971 to 2004 and data of apple growth period of agrometeorological experimentation station in Xifeng, the climate characteristic and its influence on apple growth period were analyzed.The result indicated as follows: on loess plateau of Gansu there are 3 areas in which daily average temperature of 10℃ early begins, they are located in Beidao, Lanzhou, and Jingchuan, respectively;3 areas in which daily average temperature of 10℃ late begins are located nearby Huajialing, Dongxiang, and Min county;The earliest date is on April 14 in Beidao, the latest date is on June 5 in Huajialing;Its spatial distribution characteristic is that Dingxi and Linxia are late, Tianshui, Pingliang and Qingyang are early, the northeast part of Baiyin also is early;the daily average temperature of 10℃ begins earlier and earlier, specially since the 90's, the early tendency is more obvious;In 70's major areas were late, in 80's north areas were early, south areas were late, in 90's Dingxi and Linxia were late, other areas were early.In 3 years in which beginning date of 10℃ was early, the accumulated temperature was high, sunshine was sufficient, average growth period of apple began more than 4d earlier, leaf unfolding prime and blossom telophase began 6 to 8 d earlier, every growth period in the most early year 2004 was 13 d earlier than the latest year 1993, especially the bud opening and blossoms telophase were 21 to 25 d earlier.The earliest time of bud opening, leaf unfolding prime and blossom prime was on March 20, 2004, April 8, 2001 and April 16, 2001, the latest was on April 25, April 30, and May 10, 1996, respectively.The earliest and the latest year had 36 d, 22 d, and 24 d difference.In 1984 it was early, in 1985 it was late, in 1986 it suddenly changed to be early, in 1987 it suddenly changed to be late, in 1988 to 1992 it was early, in 1993 it was late, 1994 later it continually change to be early. |