论文部分内容阅读
夏威夷桉树人工林生长快,但许多地方缺氮。由于合成氮肥成本高,故一般采用合欢木与其它树种混交来补充氮。我们在夏威夷岛上哈马夸海岸的潮湿地带进行试验,试验设计采用五种随机配置方法,反复四次,以便比较。在48个月时得出总的干产量,合欢木纯林是109吨/公顷,合欢木占11％的林分是67吨/公顷,合欢木占34—66％的混交林是103—105吨/公顷,而施肥的桉树纯林是94吨/公顷。同时,混交林和合欢木纯林内土壤氮的总量比施肥的桉树纯林要高。因此,对于高产的人工林采用这种混交方法,合欢木能为桉树提供所需要的氮。
Hawaii Eucalyptus plantations grow fast, but many places lack nitrogen. Due to the high cost of synthetic nitrogen fertilizer, it is generally used Acacia wood mixed with other species to supplement nitrogen. We experimented in the wetlands of the Hamakua coast on the Hawaiian island using five random configurations, repeated four times for comparison. The total dry yield at 48 months was 109 tons / hectare for Acacia wood pure forest, 67 tons / ha for Acacia wood 11%, and 34-66% for Acacia wood 103-105 Tonne / hectare, while the fertilized eucalyptus pure forest is 94 tons / hectare. At the same time, the total amount of soil nitrogen in mixed forest and Acacia wood pure forest was higher than that of fertilized Eucalyptus pure forest. As a result, Acacia can provide the eucalyptus with the nitrogen it needs for this high-yielding plantation.