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为了对不同生态条件下,根据表型选出的水杉优树的优劣程度进行初步鉴别,从中选出优良类型,淘汰一些优点不突出的优树。同时为减轻今后有性鉴定的工作量提供依据,我们对17个水杉无性系进行了初步当代鉴定,现将情况小结于下: 种子园自然条件 水杉种子园地处江汉平原潜江县汉江南岸蚌湖林场,年平均气温17℃,年降雨量1000毫米以上。该处1972年前为农业用地,地势平坦,地下水位较高,土壤肥力中等,PH值7.2～7.8,微碱性,解放前由于溃堤,园地曾被泥沙堆积,因此表土层50厘米下,一般有较厚的沙层。
In order to differentiate the superiority and inferiority of the optimal tree of Metasequoia glyptostroboides selected under different ecological conditions, select the good type from which, and eliminate some superior trees with less prominent advantages. At the same time in order to reduce the workload of the future identification of the basis for the provision of 17 Metasequoia clones preliminary preliminary identification of the current situation is summarized below: Seed orchard Natural conditions Metasequoia seed orchard is located in Jianghan Plain Qianjiang Xian Han River south shore Bang Lake Forest farm, the annual average temperature of 17 ℃, the annual rainfall of 1000 mm above. The area before 1972 for agricultural land, flat, high groundwater level, soil fertility, PH value of 7.2 to 7.8, slightly alkaline, due to the embankment before the liberation, the park had been sediment accumulation, so topsoil 50 cm , Generally have a thick layer of sand.