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澳大利亚维多利亚东部山麓的土生桉树林作为永续阔叶材生产林经营,轮伐期至少为80年。关于强度采伐对磷保存的可能影响作了调查,测定了桉树混交林生态系统中的磷分布,估算了锯材和剩余圆材的磷输出量。应用氟化物、酸溶液和有机态磷的等温正吸附以及在适宜的土:水比率与抽提时间下,随后持续抽出的磷水平,以研究土壤磷的有效性。估算出地上部分生物量的含磷量为21.2kg ha~(-1),采伐移出磷量为1.5～3.0kg ha~(-1)(取决于采伐强度),并估算出天然更新火烧迹地残余物损失的磷为8kg ha~(-1),根据在适宜条件下土壤连续抽提的结果,估算出森林长期生长的有效磷为57kg ha~(-1)。这是估算森林中的长期有效磷的新途径,我们用所谓“森林可用磷”来叙述这种估算。由采伐和火烧综合损失的磷占森林可用磷的18％。由此得出结论:在未能确定立地生产力的磷退化之前,这些桉树生态系统至少可强度采伐5个轮伐期。
Native eucalypt forests in the foothills of eastern Victoria, Australia, are managed as perpetually broadleaf forest with a rotation of at least 80 years. The possible impact of intensive harvesting on phosphorus conservation was investigated, the phosphorus distribution in the eucalyptus mixed forest ecosystem was determined, and the phosphorus output of sawn timber and the remaining logs was estimated. The isothermal positive adsorption of fluoride, acid solution and organic phosphorus and subsequent subsequent extraction of phosphorus at suitable ratios of soil to water and extraction time were used to study the effectiveness of soil phosphorus. It is estimated that the aboveground biomass is 21.2kg ha -1 and the phosphorus is 1.5 ~ 3.0kg ha -1 (depending on the harvesting intensity), and the residue of natural renewal is estimated The loss of phosphorus was 8 kg ha ~ (-1). According to the results of continuous soil extraction under suitable conditions, the available phosphorus in long - term forest was estimated to be 57 kg ha ~ (-1). This is a new way to estimate long-term available phosphorus in the forest, and we describe this estimate with the so-called “forest available phosphorus”. The combined loss of phosphorus from harvesting and burning accounts for 18% of the available phosphorus in forests. This concludes that these eucalyptus ecosystems can harvest at least five rotation periods before phosphorus degradation can not be established.