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沙棘是经济价值很高的灌木树种。据测定,一亩沙棘林可固氮24斤,相当于50斤尿素。6年生的沙棘林内,土壤有机质含量为2.13%,土壤含氮量为0.118%,枯枝落叶层达3厘米厚,能有效地改善土壤理化性质,提高土壤肥力,促进树木生长。因而是营造混交林的优良伴生树种。据了解,沙棘与杨树混交后,杨树生长量提高1—2倍,土壤有机质含量增加1倍以上,与油松混交可提高油松的树高、胸径生长1.5倍以上。吉县红旗林场1969年春季,在海拔1200—
Seabuckthorn is a shrub species of high economic value. According to the determination, acre seabuckthorn forest nitrogen fixation 24 pounds, equivalent to 50 kg of urea. Six-year-old seabuckthorn forest soil organic matter content of 2.13%, soil nitrogen content of 0.118%, litter layer of up to 3 cm thick, can effectively improve soil physical and chemical properties, improve soil fertility and promote tree growth. Thus is to create an excellent associated tree species mixed forest. It is understood that the seabuckthorn mixed with poplar, poplar growth increased by 1-2 times the soil organic matter content increased by more than 1 times, mixed with Pinus tabulaeformis can increase Pinus tabulaeformis tree height, diameter growth of 1.5 times more. Ji County Red Flag Forest 1969 spring, at an altitude of 1200-