桉树生物质能源的优势、现状和潜力

桉树是我国南方最重要的速生商品林树种,也是优良的能源树种.桉树因为有高效的光合作用机制,因此其人工林是世界上生长最快、生物量最大的一种人工林生态体系.桉树是有一种水分适应机制,为其提供很强的抗旱能力且能够通过树叶减少每单位叶面积的养分分配来适应恶劣环境;它还是一种典型的外生菌根植物, 因此桉树耐贫瘠能力强.桉树的天然分布区澳大利亚的自然条件多种多样,因此桉树有适应各种不同气候和地理条件的繁多种类,包括抗盐碱、耐水浸、抗风和耐寒性等特点.作为能源树种,桉树还具有以下优点:易于管理,养护成本低,易繁殖, 其大量的宿芽构成了强大的萌蘖能力,富含芳香油,抗病,抗虫.桉树能源利用的方式主要有:桉叶油,生物柴油;桉树全树的热值均高,是能源的好材料;炭化利用;液化利用.目前我国桉树人工林已达180万公顷,且每年以大于 10 % 的速度在增长.桉树的迅速发展,无论在科研、生产技术上以及产业等各方面均成熟;本文还重点介绍了澳大利亚桉树生物质能源利用的现状,在此基础上判断,我国桉树生物质能的利用条件也已经成熟.

Superiority, Situation and Potential of Eucalyptus for Bioenergy

Eucalyptus is not only one of the most important high-yield commercial forest species,but also an excellent species of energy resources. Eucalyptus plantation is the fastest growing with the largest biomass among man-made forests of the world because of its highly effective photosynthesis mechanism. Thanks to the good mechanism of water-adaptability, eucalyptus is strongly drought-resistant. Eucalyptus can also reduce nutrient distribution of per specific leaf area to adapt to adverse environment. Eucalyptus is widely adaptable to the poor and lean lands because it is a typical mycorrhizal tree. In Australia, it is easy to find many special varieties including those possessing the characteritics of good salinity-tolerance, waterlogging-tolerance, cold-tolerance or wind-resistance because eucalyptus trees are widely distributed in various types of climatical and geological environments in Australia. The advantages of eucalyptus as bioenergy resource are; easy management and low maintaining costs; easy propagation; the large amount of buds under the bark lead to strong germinating ability; resistance to disease and pest because of its abundant essential oils. The ways for utilizing eucalyptus as bioenergy resource are: transfer of essential oils to diesel oil; The whole tree is a good fuel material because of the high caloric value; Carbonization as charcoal and activated carbon; Liquefied fuels. It is estimated that currently there are 1. 8 millions hm2 eucalypt plantation in China, which continue to increase at the rate up to 10 % per year. Thanks to the quick development of the plantation, the techniques for production and utilization of eucalyptus have been well developed. This paper introduced also the present status of eucalyptus bioenergy production in Australia. Similarly, the time is ripe to produce bioenergy through eucalyptus in China.