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为了解山东毛白杨在我圃年生长规律及其特性,81年我们对其作了定期定株观察调查,以便日后对该种苗木人工调控管理提出一些参考依据。一、圃地自然环境及育苗措施简介我校苗圃地势平坦,土层深厚为川地褐土,地下水位3米左右,土壤含速效磷5.8ppm,含 N 量0.086％,有机质1.127％,PH 值7.5,年平均气温9.8℃,气温稳定通过10℃的多年平均积温值为3426℃,一般终霜期在4月中旬,初霜期在10月上旬,无霜期
In order to understand the law and characteristics of annual growth of Populus tomentosa in our country, we made regular observation of its growth in 81 years so as to provide some references for the artificial regulation and control of the seedlings in the future. First, the garden of natural environment and nursery measures Brief introduction Our school nursery flat, deep soil for the Cinnamon soil, groundwater level of about 3 meters, the soil containing available phosphorus 5.8ppm, N content 0.086%, organic matter 1.127%, PH value 7.5, the average annual temperature of 9.8 ℃, the average temperature through the 10 ℃ for many years the average accumulated temperature of 3426 ℃, the general end of frost in mid-April, the first frost in early October, frost-free period