论文部分内容阅读
为了改变我县的树种单一问题,从一九六四年到一九七九年,全县引种樟子松一万三千亩。目前,最大的已达十八年生,最小的为三年生。都表现了耐瘠薄、耐干旱、抗风沙、生长快而稳定的特点。最近调查表明。1.高生长:东岭林场院内的十八年生的樟子松平均高7.2米,每年平均生长40厘米。最高的10.5米。东岭营林区九年生的平均高3.36米,年平均生长37.3厘米,最近三年高生长均超过45厘米,最高的达4.88米,2.直径生长:十八年生的樟子松平均胸径20.8厘米,年平均生长1.15厘米。九年生的地径生长6.6厘米,最粗7厘米。3.材积生长:十八年生的平均胸高20.8厘米,单株材积0.150立米。每公顷按六百株
In order to change the single tree species problem in our county, from 1964 to 1979, the county introduced 13,000 acres of Scotch Pine. At present, the largest is eighteen years old, the youngest is three years old. Have shown resistance to infertility, drought, wind sand, fast and stable growth characteristics. A recent survey shows. 1. High Growth: The eighteen-year-old Pinus sylvestris in Dongling Forest Farm has an average height of 7.2 meters and grows an average of 40 centimeters per year. The highest 10.5 meters. The average annual height of nine-year-olds in Donglingying forest area is 3.36 meters and the annual average growth rate is 37.3 centimeters. In the recent three years, the height growth is more than 45 centimeters and the highest is 4.88 meters. 2. Diameter growth: 18-year-old Pinus sylvestris average diameter 20.8 Cm, the average annual growth of 1.15 cm. Nine-year-old diameter growth of 6.6 cm, the most coarse 7 cm. Volume growth: Eighteen-year-old average chest height of 20.8 cm, single plant volume of 0.150 cubic meters. Six hundred plants per hectare