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福建含笑杉木混交林幼龄期生产力及生态特性研究 总被引:2,自引:0,他引:2
苏秀城 《中南林业科技大学学报(自然科学版)》2000,20(4):76-80
为开发利用优良珍稀阔叶树资源、增加造林树种生物多样性及防治人工林地力衰退,对福建含笑纯林及福建含笑×杉木混交林进行造林试验,研究了福建含笑杉木混交林幼龄期的林分生产力、小气候特征以及土壤改良效果与机制.结果表明,福建含笑杉木混交林林分生物量和生产力较高,具有调节林分小气候、改善土壤环境状况、充分利用营养空间、提高土壤微生物数量及土壤酶活性等生态特性,从而促进林木的生长,是一种较好的混交组合,值得推广应用. 相似文献
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调查福建柏杉木混交林和福建柏纯林人工林的林分生长状况,林下植被生物多样性以及林下土壤的养分状况,结果表明:福建柏纯林植被状况较好,林下植被的丰富度指数和多样性指数均大于福建柏杉木混交林;福建柏纯林土壤的养分状况较好,维持较高的土壤肥力。从提高林地的生产力上看,杉木与福建柏属浅根性树种,种间竞争激烈,混交效果不好,福建柏与杉木混交这个模式不宜大面积造林推广。 相似文献
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酸枣杉木混交林林分生长研究 总被引:1,自引:2,他引:1
为解决目前南方林区人工林针叶化引起的系列生态问题,挖掘本地乡土树种,发展阔叶树种造林,通过营造不同混交模式的酸枣杉木混交林,进行不同混交模式酸枣杉木混交林林分生长效应的比较研究,结果表明:不同混交比例的酸枣杉木混交林群落特征和林分生长存在较大差异,不同林分蓄积量大小排序为:酸枣纯林>酸枣×杉木(1∶3)混交林>酸枣×杉木(1∶2)混交林>酸枣×杉木(1∶1)混交林>杉木纯林,其中杉木×酸枣(3∶1)混交林是种间关系较为协调并具较高生产力的混交模式,值得南方林区大力推广。 相似文献
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大力营造混交林提高林业生态建设质量 总被引:2,自引:0,他引:2
我国造林在林种配置上 ,用材林多、防护林少 ;在树种结构上 ,针叶林多、阔叶林少 ,纯林多、混交林少 ,针阔混交林更少。人工林保存面积中混交林所占比重不足 10 % ,而且树种单一 ,生物多样性差 ,层次结构简单 ,导致地力衰退 ,生产力下降 ,病虫害严重 ,严重影响着社会、经济的可持续发展。1 混交林的作用效果根据造林目的的不同 ,合理搭配混交树种 ,选择适宜的混交方法和确定适当的混交比例 ,以形成具有明显差异的多层次垂直结构的混交林 ,具有增加产量 ,改良土壤 ,减免自然灾害 ,保持水土流失 ,预防森林火灾 ,美化风景等方面的综合效果。1.… 相似文献
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【目的】揭示国内外单树种纯林经营,特别是单树种针叶纯林经营和连作经营,所引起的土壤质量退化和林木生长量下降的状况及其作用机制,阐明发展有群落结构混交林是维护、恢复和提高森林土壤功能的机制及其经营技术途径。【方法】依据多年来研究我国主要造林树种人工林土壤质量退化的状况与机制,及其防治技术的实践,广泛查阅国内外有关资料,深入研究国内外单树种纯林经营、特别是针叶纯林经营、连作经营引起土壤质量下降及其防治措施的进展。通过对比的方法,即比较单树种纯林与相似立地条件、不同林分类型混交林土壤的理化性质及生物学活性变化的差异,揭示单树种纯林、特别是针叶纯林经营和连作经营引起土壤质量下降的机制,阐明混交林维护、恢复和提高土壤功能的机制及其技术途径。【结果】相似立地条件下,单树种纯林、特别是单树种针叶纯林经营和连作经营,与不同林分类型的混交林比较,其凋落物量下降,土壤有机质的量和质下降、有效磷含量下降、交换性阳离子含量下降、pH值下降、土壤生物化学活性下降、土壤肥力下降,病虫害严重,林木生长量下降。研究也阐明了发展我国主要造林树种混交林可选择的混交树种、混交比例和混交模式,指出了改造现有的单树种纯林、特别... 相似文献
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针对人工针叶造林面积不断扩大,出现多代连栽,导致地力衰退,林分生产力下降的现状,进行了多树种混交造林的实验,分析了多树种造林方式对土壤肥力的影响,探讨了多树种混交造林对维持和恢复土壤肥力的影响。结果表明:7年生多树种林与杉木纯林相比,土壤理化性状趋好;土壤微生物数量以及三大异养微生物菌群数均以多树种混交林为优。 相似文献
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为解决目前南方林区人工林针叶化引起的系列生态问题,发展阔叶树种造林,应用平均标准木法和样方收获法对桤木×杉木混交林各模式林分的生物量、分配比例及分布格局进行研究,结果表明:不同经营模式的林分的生物量及生产力由高到低为:行间混交、行带混交、株间混交、杉木纯林,以行间混交的乔木层生物量及生产力最高,分别为68.66(t/hm2)和6.86(t/hm·2a);混交林各经营模式的营养空间分布均比杉木纯林合理,能较好地促进林木生长。 相似文献
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研究52 个乔木树种纯林的碳储量,分析其固碳能力差异,为碳汇造林选用乔木树种提供参考
依据。以广东省东江林场11 年生的乔木树种试验林为研究对象,测定52 个树种生长量和树干、树枝和
树叶的含碳率。按照平均木法,算出平均木生物量,结合平均含碳率、林分密度与保存率,估算碳储量。
结果表明,不同树种林分碳储量差异极大,最高碳储量(厚荚相思Acacia farnesiana)比最低碳储量(紫
玉兰Magnolia liliiflora)相差约20 倍,年均碳储量在10 t/hm2 以上的树种有含羞草科的厚荚相思、大叶
相思A. auriculiformis 等5 个树种,年均碳储量在5~10 t/hm2 的有灰木莲Manglietia glanca、红荷Schima
wallichii 等18 个树种。以保存率和单位面积碳储量2 个主要性状作聚类分析,可将52 个树种按固碳能力
划分成4 种类型的碳汇树种。 相似文献
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Wood net primary production resilience in an unmanaged forest transitioning from early to middle succession 总被引:1,自引:0,他引:1
Christopher M. Gough Christoph S. Vogel Brady Hardiman Peter S. Curtis 《Forest Ecology and Management》2010
The mixed deciduous forests of the upper Midwest, USA are approaching an ecological threshold in which early successional canopy trees are reaching maturity and beginning to senesce, giving way to a more diverse canopy of middle and late successional species. The net primary production (NPP) of these forests is generally considered past peak and in decline, but recent studies show a striking resilience in the NPP trajectories of some middle and late successional forests; yet, the mechanisms controlling such temporal changes in NPP are largely unknown. At the University of Michigan Biological Station in northern Michigan, we used a ≥9-year continuous record of wood net primary production (NPP), leaf area index (LAI), canopy composition, and stem mortality in 30 forested plots to identify the constraints on wood NPP as a mixed forest transitions from early to middle succession. Although wood NPP decreased over time in most stands, the rate of decline was attenuated when the canopy comprised a more diverse assemblage of early and middle/late successional species. The mechanism for sustained NPP in stands with more species diverse canopies was the proliferation of LAI by intact later successional tree species, even as stem mortality rates of early successional trees increased. We conclude that projections of carbon sequestration for the aging mixed forests of the upper Midwest should account for species composition shifts that affect the resilience wood NPP. 相似文献
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研究了多竹种混交、竹桉混交和竹橡胶混交对林木生长及林分土壤条件的影响。结果显示:不同竹种混交以及竹树混交其林木生长状况及土壤条件均优于纯林;竹子纯林、多竹种混交林、竹树混交林3种不同类型的林分其土壤含水量和有机质含量排序为:多竹种混交林 > 竹子纯林 > 竹树混交林 > 乔木纯林。研究结果表明,在桉树林和橡胶林中适当套种竹子可以改善桉树林和橡胶林的生长环境,增强生态系统的稳定性,对于维护生态平衡、提高林地生产力、维持土壤肥力具有显著作用。研究结果可为桉树和橡胶树纯林的改造提供理论支持。 相似文献
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光泽县残次天然阔叶林改造试验 总被引:1,自引:0,他引:1
根据生态学原理,把天然更新和人工改造更新相结合,对光泽县林业试验场残次天然阔叶林进行改造,通过改造可很快地形成多树种的混交林,林木材积提高114.6%~218.6%,土壤物理性质比杉木纯林好,土壤蓄水量比杉木纯林提高80.7%~91.5%,有良好的生态经济效益,实践证明,残次天然阔叶林改造是加速培育森林资源的好途径。 相似文献
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秃杉与杉木、木荷混交林林分生长初步研究 总被引:2,自引:0,他引:2
通过秃杉×杉木、秃杉×木荷混交试验,并与秃杉纯林、木荷纯林、杉木纯林、杉木×木荷混交林对比,15 a的试验结果表明:秃杉与杉木、木荷混交后,促进了林木的生长,混交林胸径、树高、材积的生长量都大于秃杉纯林,增益可达18%~28%以上。其中秃杉×杉木、秃杉×木荷混交林是种间关系较为协调并且具有较高生产力的混交模式,可以在生产上推广应用。 相似文献
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Admixing broadleaved to coniferous tree species: a review on yield, ecological stability and economics 总被引:2,自引:1,他引:1
Thomas Knoke Christian Ammer Bernd Stimm Reinhard Mosandl 《European Journal of Forest Research》2008,127(2):89-101
For several reasons the conversion of mono-species into mixed-species forests is presently a major concern of forest management and policy in Central Europe. Although it is possible to show a clear trend in favour of mixed-species forests, private forest owners and some forest economists have often not favoured mixed forests, assuming that they are less profitable. The trend towards mixed forests seems mainly for ecological reasons, while sound economic analysis of mixed forests is still rare. Based on this background the objective of the study is to answer the following four questions: (1) Does the yield of mixed-species forests differ from that of pure forests? (2) Does the mixing of tree species influence the ecological stability of forests? (3) Is the economic value of a mixed forest less than that of a monoculture? (4) How do forest economic models integrate the findings on yield and ecological stability of mixed forests? To answer these questions a literature review was conducted on the possible impacts of mixed-species forests. In comparison to pure stands a greater yield is not necessarily given in mixed stands. Yet, mixed-species stands are better able to compensate disturbances than monocultures. Moreover, there is substantial evidence that mixed-species stands are more resistant against biotic and abiotic disturbances. Applying an extended forest economic model, it was possible to demonstrate that mixing large blocks of native broadleaf species into pure conifer forests may lead to a significant reduction of financial risk. From a risk-averse perspective the economic value of a mixed-species forest may thus be greater than that of a mono-species forest. Yet, it became clear that forest economists do not often integrate the research findings on yield and ecological stability of mixed stands in modelling, but rather apply simple bioeconomic modelling. Moreover, in the context of mixed forests economists also largely ignore even classical financial approaches, which consider risk and risk preferences. We concluded that forest economics has to close substantial research gaps. Firstly, the knowledge of how to integrate biophysical properties of mixed forests in bioeconomic modelling is still an open question. Secondly, forest economists have to adopt the modern approaches of financial theory and management science to value mixed forests. 相似文献
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对广东省中山市五桂山区长命水村 2 个湿地松(Pinus elliottii)与乡土阔叶树种改造的混交
林,以及对照湿地松纯林的相关植物的生长指标进行调查分析,对其林下植物多样性进行对比。结果表
明:利用乡土阔叶树种对湿地松纯林的改造具有一定的效果。不同树种在改造样地中生长表现出的差异
较大,大叶相思(Acacia auriculiformis)和台湾相思(Acacia confuse)的胸径和树高年平均生长量分别为
2.04~4.00 cm 和 1.82~1.86 m,表现最好。2 个改造样地林下植物多样性与对照地存在较大差异,且均比对
照地好。总体分析,大叶相思、台湾相思和柠檬桉 (Eucalyptus citriodora) 生长最迅速,各项生长指标较
其它树种快,是改造湿地松林的优良树种。 相似文献
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在山西庞泉沟自然保护区选取典型森林群落5类,设置15块样地,采用Rao指数和CWM指数计算群落的功能多样性指数,分析了不同森林群落功能多样性指数及其生态学意义。研究结果表明:不同群落类型群落功能Rao指数和CWM指数表现一致,基本排序为:华北落叶松混交林>云杉混交林>油松混交林>阔针混交林>阔叶树混交林,群落内不同层次间排序为:乔木层>灌木层>草本层。群落功能多样性指数与物种多样性指数呈显著正相关,并与群落生产力等功能特性密切相关。 相似文献