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在对湖南优良乡土树种原产地进行反复调查研究,进行多年引种栽培试验的基础上,提出优良乡土树种引种栽培方法、步骤以及技术要点.根据引种试验中各树种的生长情况以及注重树种的经济价值、观赏价值、生态效益的引种原则,筛选出了40余种能适应本省不同立地条件的优良乡土树种,并进行中试或在生产中推广应用,结果表明,这些树种中,有的可作用材树种,有的可作经济林树种,有的可作园林和绿化树种.并提出了各树种的推广栽培范围. 相似文献
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依据利用价值进行分类,赤峰市现有灌木资源可分为纤维类、油脂类、药用类等7类。赤峰市灌木资源丰富,蓄积量大,共有树种169种,而且用途广泛,一个树种有的还同时具有多种用途。在大力开发赤峰市灌木资源的同时,还应充分利用每一树种的多种用途,做到材尽其用。对于利用价值高、开发潜力大的灌木树种应充分开发和利用,变资源优势为经济优势,更好地为经济建设服务。在实际利用中,建议大面积人工栽培,增加蓄积量,并对他们进行充分的合理利用,以创造尽可能多的经济价值。在利用的同时要注意保护.不仅保护珍稀树种.还要保护天然植被,以使赤峰市灌木资源得到更加充分的利用。 相似文献
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太行山石灰岩中山区树种选择研究初报 总被引:5,自引:1,他引:4
对石灰岩中山区两个立地条件,包括干旱阳坡24个水保林树种,阴坡9个造林树种进行了综合评分。结果为干旱阳坡乔木树种以樟子松、侧柏、油松得分最高,分别为4.86、4.43、4.29;小乔木及灌木树种以沙棘、翅果油树、荆条得分最高,分别为3.71、3.43、3.29;阴坡以樟子松、油松、沙地柏得分最高,分别为5.0、4.0、3.29。在选择造林树种时,除参考综合评分外,还应考虑立地条件,造林目的和造林方法,以及树种特性和经济价值加以选择。 相似文献
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文冠果是晋北地区常见的乡土经济树种,在荒山绿化和产业发展中具有重要的生态价值和经济价值,是山西省特色经济林造林树种之一。介绍了晋北地区文冠果育苗与造林技术。 相似文献
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珍贵树种具有材质优良、用途广泛、经济价值高等特点,被广泛应用于建筑、家具、装饰装修、军工、航天、车船、造纸及纤维材、化工、医药等方面。通过实施珍贵树种培育,增加了珍贵树种比例,调整了树种结构,提高了林分质量,加速了森林演替进程,使天然林特别是珍贵树种资源得到了有效的保护和恢复,增加了森林生态系统的稳定性,使森林在维持生态平衡方面的作用得到充分发挥。在培育珍贵树种方面,黑龙江省森工林区起步较早,积累了许多宝贵经验。 相似文献
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美国东部黑核桃的经济价值及生物学持性 总被引:4,自引:1,他引:3
1经济价值黑核桃(Juglans.nigra)起源于美国,它不仅可生产珍贵的木材,而且生产上等的坚果,用途广泛的果壳粉,是一种经济价值很高的树种。黑核桃在美国木材生产中占有重要的地位,木材结构紧密,力学强度高,纹理、色泽美观,尤宜作为高档家具及胶合板... 相似文献
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许国强 《林业机械与木工设备》1999,(9)
随着经济的发展和人民生活水平的提高,将珍贵树种木材制成的薄木贴在人造板表面作装饰已成为时尚.然而,珍贵树种的木材产量逐渐减少,薄木的价格越来越高,国内各生产企业为了提高薄木出板车和降低生产成本,已将薄木的厚度降到0.5mm以下.但要提高珍贵树种木材的利用率,减少优质木材浪费,生产中还必须注意许多问题,本文就薄木生产时应注意的几个问题加以分析如下。1木方部制如何刻制木方和合理截断原木是能否生产出优质、美观的薄木和提高珍贵树种木材利用率的关键.在截断原木时,应尽量根据原木外部特征,正确判断木材的各种缺陷… 相似文献
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We present a new approach for selecting seed sources of Eucalyptus to be grown on saline land. We evaluated our method using 22 seed sources, 11 tree-form species and 11 mallee-form species.
We found that the commonly used strategy of selecting seed sources on the basis of average productivity was inappropriate,
as average productivity was poorly correlated with the relationship between productivity and salinity that was actually observed.
Using our new approach, we categorized seed sources as salt-sensitive or salt-tolerant based on the strength of the observed
relationship between salinity and productivity. Seed sources defined as sensitive were associated with relatively large (−24.8
to −64.2%) productivity losses, while the changes in productivity for tolerant seed sources ranged from −17.1 to 10.5%. On
average, reductions in height due to increased salinity were about 30% greater for sensitive seed sources than tolerant ones,
although the effect was smaller for mallee-form and greater for tree-form seed sources. The difference between sensitive and
tolerant seed sources was similar after 1, 2 and 4 years of growth. 相似文献
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王珊子 《绿色中国(A版)》2006,(15):66-68
“民以食为天”,“人命关天”,这两句古话阐明了食品安全无以复加的重要性。实际上,食品安全的重要性还远不止于此,这个问题不仅关系到人的健康和生命,而且关系到经济发展、社会稳定,乃至公民对整个社会和政府的信心。 相似文献
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王珊子 《绿色中国(综合版)》2006,(8):66-68
“民以食为天”,“人命关天”,这两句古话阐明了食品安全无以复加的重要性。实际上,食品安全的重要性还远不止于此,这个问题不仅关系到人的健康和生命,而且关系到经济发展、社会稳定,乃至公民对整个社会和政府的信心。[编者按] 相似文献
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《Journal of Sustainable Forestry》2013,32(3-4):307-316
Concerns for maintaining biodiversity have led to the adoption of ecosystem management as the paradigm for federal land management. This approach will identify desired future conditions as the goal for management, based on ecological objectives for a given landscape. Some management efforts attempt to identify desired future conditions based on existing successional stages as defined by a classification of overstory vegetation types. Such an approach ignores most of the underlying ecological parameters of the landscape, and is inadequate for identifying past disturbance regimes and future successional pathways. An assessment of desired future conditions based on an ecological classification system is essential to overcome these inadequacies. The strategy proposed in this paper uses an appropriate ecological land classification, based on either ecological land types or habitat types, included in a broader hierarchical classification system. It also uses a vegetation map of existing overstory vegetation. These two maps are overlaid to generate polygons of ecological units that can then be used to create an ecosystem diversity matrix. Each polygon (stand) can be evaluated as to its composition and structure relative to its possible placement within the ecosystem diversity matrix through comparisons with historical ranges of variability. The overall ecosystem diversity matrix can then be examined in terms of the distribution of successional stages within each habitat type or ecological land type. The goal should be to maintain at least adequate ecological representation of all successional stages within each habitat type that occurred historically, based on past disturbance regimes. Adequate ecological representation is defined as sufficient size and distribution of inherent ecosystems to maintain viable populations of all endemic species dependent on these ecosystems. This approach can maintain and enhance regional biodiversity, but also maintain flexibility in land management options. 相似文献
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12个桃品种的花芽休眠需冷量和开花需热量 总被引:3,自引:0,他引:3
在浙西南地区研究12个桃品种花芽休眠需冷量和开花需热量生态指标.犹他模型测定结果显示:12个桃品种中,花芽休眠需冷量低的品种为春蜜、超红、中油11号、中油7号、中油4号,约为550~650 cu;其次是丽油5号、仓方早生、燕红、丽油3号、早凤凰,约为650~ 800 cu;需冷量高的品种为新川中岛和赤月,约为900~ 950cu.同一地区不同品种需热量差异较大,同一品种年际间差异相对较小.以生长度天模型试验结果表明:开花需热量低的品种为赤月和丽油3号,大约400 ~ 500 d·℃;其次是新川中岛,大约500~600 d·℃;春蜜、丽油5号、早凤凰、中油4号、中油7号、仓方早生和燕红大约600 ~ 700 d·℃;需热量较高的是中油11号和超红,约为700~800 d·℃.12个桃品种花芽休眠需冷量与开花需热量之间呈乘幂函数曲线显著负相关. 相似文献