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一、观察区的自然概况观察区设在辽阳县唐马乡林场。该场土壤为黑粘土,春季多风干旱,夏季多雨,年平均降雨量700—800毫米,地下水位在1.3米左右,年平均温度7.5—9.5℃,无霜期为160天左右,冰冻期3—4个月。标准地设在2年生北京杨用材林地,平均树高2.3米,平均胸径1.5厘米,林下间种大豆。二、分布及寄主杨黑点叶蜂(Pristiphora conjugata Dahlb)国内主要分布于辽宁、内蒙等地。我们在辽阳地区调查为害寄主有:北京杨、小叶杨、健杨、加拿大杨等二十五种杨树。
First, the natural observation area observation area is located in Liaoyang County Tangma Township forest farm. The soil is black clay, windy and dry in spring, rainy in summer, with an average annual rainfall of 700-800 mm, groundwater level of about 1.3 meters, the annual average temperature of 7.5-9.5 ℃, frost-free period of about 160 days, frozen 3-4 Months. Standard two-year Beijing Yang timber timberland, the average height of 2.3 meters, an average diameter of 1.5 cm, the understory of soybean. Second, distribution and host Yang black point leaf bee (Pristiphora conjugata Dahlb) mainly distributed in China, Liaoning, Inner Mongolia and other places. We Liaoyang area victimized host investigation are: Beijing Yang, Populus, Jian Yang, Canada Yang and other 25 kinds of poplar.