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51.
桉树给人类带来了不可估量的生态效益和经济效益。本文就桉树人工林的现状及生态问题展开详细论述,并就如何健康发展桉树产业提出合理的建议。 相似文献
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本文对15种桉树在广西桂北区引种适应性进行了比较。苗期研究结果表明：粉绿桉、白皮桉、史密斯桉、毛皮桉、溪谷桉、高桉、辐射桉7种桉树在苗期出芽率、成苗质量上表现较差。对邓恩桉、柳桉、本沁桉、巨桉、赤桉、粗皮桉、丰桉、辐射桉、白皮桉、大花序桉10种桉树进一步造林试验,结果表明：2a生的平均保存率以丰桉最高,达84.5％,其次是柳桉、粗皮桉、邓恩桉、赤桉、巨桉,较差的为本沁桉、辐射桉、白皮桉三种。树高生长情况来看邓恩桉、丰桉、巨桉、本沁桉、赤桉、柳桉具有很好适应性,白皮桉、粗皮桉、大花序桉表现一般,辐射桉最差。胸径生长上,邓恩桉、本沁桉、巨桉和柳桉为生长比较大一类,表现一般的赤桉、粗皮桉和丰桉,较差的为白皮桉、大花序桉、辐射桉。同样2a和2.5a蓄积量上比较,邓恩桉、本沁桉、巨桉比平均值高,丰桉、柳桉、赤桉、粗皮桉、大花序桉、白皮桉均低于平均值。聚类分析可分三类：邓恩桉、本沁桉、巨桉、丰桉适应性强、速生的品种,而赤桉、粗皮桉、柳桉、白皮桉表现一般、大花序桉较差;其中邓恩桉最突出。不同桉树适应性与其抗寒性有关。 相似文献
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海南岛西部地区桉树速生丰产林优化栽培模式研究 总被引：4，自引：0，他引：4
对在海南岛儋州林场实施的桉树速生丰产林栽培模式研究进行了总结。尾叶桉、刚果号桉施肥与株行距配置试验结果表明:施肥对幼林期尾叶桉、刚果号桉生1212长均有极显著的差异影响,不同的施肥配比和施肥量对尾叶桉生长的施肥效果是:B2 N0P150K160> B4 N90P200K160 >B3 N90P150K160> B1 N0P0K0(对照);对刚果号桉的效应是:12A3 N90P150K160> A4 N90P200K160> A2 N0P150K160> A1 N0P0K0;在相同的密度下不同的株行距配置方式对尾叶桉、刚果号桉的生长无影响,差异不显著。年生刚果号桉整地、密12312度与施肥试验结果表明:整地、施肥对家系和无性系的树高、胸径生长和胸径生长有影响,且差异极显著;密度仅对刚果号桉无性系胸径生长有影响且差异显著。三因素对12刚果号桉生长的影响程度为:整地>施肥>密度。—年生的四种人工林优化栽培模1236式分析结果表明:在同一立地类型,相同的栽培抚育管理措施下,选择适宜的良种是确保人工林实现丰产的关键;同一立地类型相同的栽培抚育措施下,刚果号桉行间间种12绢毛相思比间种大叶桃花心木生长量高;粗果相思在海南岛西北部的儋州地区发展潜力比马占相思大。 相似文献
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中国桉树研究现状与科学经营 总被引：4，自引：0，他引：4
本文从三个方面进行阐述,首先简要说明桉树的用途(纸浆材、锯材、桉油的加工利用、园林绿化、桉树生态林)；重点论述了当前桉树研究现状和成果(包括纸浆材、桉树珍贵树种及大径材培育、耐寒桉树、材性及加工、桉树与环境、桉树育种新技术及现代化育苗技术等)；并提出了科学经营的措施(确定一个目标,选好两个基础,抓住五大要素),为桉树的研究与生产提供科学的依据。 相似文献
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We have developed a convenient new method of ageing grasstrees (Xanthorrhoea) and determining their fire history over the last 250 years or more. Grinding off the charred leafbases reveals alternating cream and brown bands that we equate with annual growth cycles and occasional black bands that we equate with the passage of fire. The new method was employed on 159 grasstrees at 50 sites distributed throughout the dry eucalypt forest region of southwestern Australia. In the 80 years prior to European settlement in 1829, and for the next 40 years, fires were recorded on grasstrees at 3–5 year intervals. The ensuing decline in mean fire frequencies and increased variability corresponded with demise of the aboriginal inhabitants and onset of intense wildfires associated with unrestrained logging. Our data show that from 1920 attempts at fire exclusion followed later by prescribed burning programs were only partly successful. Currently recorded intervals on individual trees of 10–20 years are consistent with further changes in fire management practices. Both extremes would have had significant impacts on the biota. 相似文献
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An important challenge for riparian management is to determine the extent to which landscape context influences the faunal assemblages of riparian habitats. We examined this challenge in the variegated landscapes of southeastern Queensland, Australia where riparian vegetation is surrounded by both extensive grazing and intensive cropping. We investigated whether riparian habitats adjacent to different landuses support similar bird assemblages. Three types of riparian habitat condition were sampled (uncleared ungrazed; uncleared grazed; cleared grazed) in four different land-use contexts (ungrazed woodland; grazed woodland; native pasture; crop) although only six of the 12 possible treatment combinations were available. Eighty percent of bird species responded significantly to changes in both riparian habitat condition and landscape context, while fewer than 50% of species were significantly influenced by landscape context alone. The influence of landscape context on the bird assemblage increased as the surrounding land use became more intensive (e.g., woodland to native pasture to crop). Riparian zones have been shown to have consistently high biodiversity values relative to their extent. These findings suggest it is not enough to conserve riparian habitats alone, conservation and restoration plans must also take into consideration landscape context, particularly when that context is intensively used land. 相似文献
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《Wood material science & engineering》2013,8(3):165-173
ABSTRACTIn the present work, Eucalyptus nitens was thermally modified in an open (atmospheric pressure) and a closed (under pressure) reactor system. The effect of the changes of the chemical composition on the mechanical properties was investigated. Hemicelluloses, cellulose, lignin, extractives, acetic acid, formic acid, total phenols and the cellulose degree of polymerization (DP) as well as modulus of elasticity (MOE) and modulus of rupture (MOR) were measured for each modification. The results indicated that the closed system modification, particularly at high pressure, presented stronger variations on the chemical structure of the modified wood than the modifications in the open system. In both modifications, MOR showed a better correlation with the chemical changes than the MOE, especially xylose, cellulose DP, lignin and total phenols. These correlations suggest a tendency of a more brittle wood in the closed system modification at high pressure than in the modifications in the open system. Results can be used as a reference for future applications of thermally modified E. nitens wood. 相似文献
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为了解《桉树科技》由半年刊改为季刊后的刊文情况,本文对《桉树科技》2012-2015年的载文量及刊文类型、第一作者信息、刊文被引、下载及引文情况、刊文作者数及合作情况、单产和多产作者及核心第一作者情 况、基金资助论文等方面进行了统计和分析.结果显示:《桉树科技》2012-2015年平均载文量为40篇·年-1,中级职称以下人员是该刊第一作者的主体,他们学历层次较高且以30岁以下的青年居多,科研院所为主要供稿单位.除2015年外,2012-2014年的刊文被引率接近或高于50％;4 a篇均引文量为17.2条,单篇被引及下载量排名前5累计10篇的刊文中,共有7篇出自国家林业局桉树研究开发中心.2012-2015年4a篇均作者数约4人,平均合著率为92.1％,单产作者和多产作者分别占所有作者数的80％和20％.基金论文率为78.1％. 相似文献
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J.J. Hollis S. Matthews R.D. Ottmar S.J. Prichard A. Slijepcevic N.D. Burrows B. Ward K.G. Tolhurst W.R. Anderson J.S. Gould 《Forest Ecology and Management》2010
Five models for the consumption of coarse woody debris or woody fuels with a diameter larger than 0.6 cm were assessed for application in Australian southern eucalypt forest fires including: CONSUME models for (1) activity fuels, (2) natural western woody and (3) natural southern woody fuels, (4) the BURNUP model and (5) the recommendation by the Australian National Carbon Accounting System which assumes 50% woody fuel consumption. These models were assessed using field data collected as part of the woody fuel consumption project (WFCP) in south-west Western Australia and northern-central Victoria. Three additional datasets were also sourced to increase variability in forest type, fuel complex and fire characteristics. These datasets comprised data from south-west Western Australia collected as part of Project Aquarius, the Warra Long Term Ecological Research site in Tasmania and Tumbarumba in south-eastern New South Wales. Combined the dataset represents a range of fire behaviour characteristic of prescribed burning conditions with a maximum fireline intensity of almost 4000 kW m−1. 相似文献