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一、立地条件 乌鲁木齐市自一九七五年开始引种,进行直播留苗建园。现将引种生长表现及结实情况概述如下: 引种试验地位于乌鲁木齐北郊四宫种苗场的西北角,面积七十八亩。一九七五年春季直播造林,建立试验园。 引种区为自然特点:夏季酷热,冬季严寒温差变幅大。极端温度分别达±40℃,年平均气温5.6℃,一般五个月在零度C以下,初霜期十月上旬,终霜期五月上旬,全年无霜期153天,总日照2818.4小时,年降水量194.6毫米,年蒸发量2570毫米,蒸发量超过降水量的13倍,相对湿度61％。土壤系属戈壁砾土。土层厚度20～100厘米,下为砾石层,上部土层有
First, the site conditions Urumqi since 1975 introduction, live Liumiao built Park. Now the introduction of growth performance and seed conditions are summarized as follows: The introduction of the test site is located in the northern suburb of Urumqi, Gong Gong seedling field northwest corner, an area of seventy-eight acres. In the spring of 1975, afforestation was broadcast live and a test garden was established. The introduction of the natural characteristics of the region: hot in the summer, cold winter temperature range amplitude large. The extreme temperatures are respectively ± 40 ℃ and the annual average temperature is 5.6 ℃. Generally five months are below zero C, the first frost period is in early October, the last frost season is early May, the annual frost-free period is 153 days, the total sunshine duration is 2818.4 hours and the annual precipitation is 194.6 Mm, the annual evaporation of 2570 mm, the evaporation of more than 13 times the precipitation, the relative humidity of 61%. Gobi soil tied to the soil. Soil thickness of 20 to 100 cm, the next gravel, the upper soil there