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刘彦海 《内蒙古林业调查设计》2014,(1):56-58,67
文章对内蒙古大兴安岭林区,森林天然更新效果与林地环境关系进行了分析,为便于更好的利用天然更新,从而达到森林资源及时恢复、增加林地总量、扩大森林面积、提高林地生产力的目的。 相似文献
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林地天然更新决定着该地区森林群落未来的发展趋势,对提高森林群落稳定性起到重要作用。文章以土默特左旗有林地、无立木林地、宜林地为研究对象,根据森林资源规划设计调查数据,分别从优势树种、郁闭度、坡度、坡向、林型等方面,对林地天然更新状况进行分析。结果表明,土默特左旗林地天然更新整体不良,后期还需施以一定人工措施促进天然更新,实现森林资源可持续发展。 相似文献
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油松天然更新的调查研究 总被引：1，自引：0，他引：1
油松的天然更新,是以油松林木的自身能力,借助于自然条件进行天然下种、恢复森林的。因此,油松林地的天然更新好与坏,直接影响油松林分是否长期生存、速生丰产和永续利用的大问题。为了更好地掌握和利用影响油松天然更新的因子。我们对沈阳市东南山区内的油松林地天然更新状况进行了调查研究,从中摸索油 相似文献
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为了解鄂西南山地常绿落叶阔叶混交林采伐迹地不同更新方式对林地土壤肥力的影响,采用典型样地法对木林子自然保护区山地常绿落叶阔叶混交林迹地3种更新方式林分的土壤进行了采样分析。结果表明:土壤容重表现出人工更新>人工促进天然更新>天然更新。土壤总孔隙度和毛管孔隙度差别不大,非毛管孔隙度人工更新林地较高。土壤自然含水量、最大持水量、毛管持水量、田间持水量等水分因子以及土壤有机质、全氮、水解氮、速效磷、速效钾和pH值等化学性质均表现出人工更新<人工促进天然更新<天然更新。3种更新方式土壤理化性质差异较大,林地土壤肥力表现出人工更新<人工促进天然更新<天然更新。 相似文献
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经实地调查，绰源林业局的近、成、过熟林中，天然更新效果较好，但因林型以及林分的郁闭度和优势树种组成等的不同，其天然更新状况具有明显的差异，文章着重对此进行了论述，并对无林地的天然更新进行了分析，为营林规划和组织林业生产等提供参考。 相似文献
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闽粤栲人工促进天然更新林分特征及土壤肥力 总被引：3，自引：0，他引：3
《林业勘察设计》2016,(4)
为探讨闽粤栲人工促进天然更新林分特征和土壤肥力,笔者于2015年以闽粤栲人工促进天然更新林为研究对象,通过对其林分结构、林木生状况、乔木生物量、地被物生物量、凋落物现存量、土壤的物理化学性质等测定,探讨了闽粤栲人工促进天然更新林林分特征、土壤肥力及物种多样性,了解不同的闽粤栲人工促进天然更新林分生长情况以及林地土壤肥力的改善,揭示了闽粤栲人工促进天然更新林的林分特征与土壤肥力,为科学指导闽粤栲林分培育提供依据。 相似文献
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天然更新油松林木生长进程分析 总被引：1，自引：0，他引：1
《山东林业科技》2016,(1)
本文通过对油松林皆伐后天然更新29年林分平均木树干解析,分析得到了不同于普通油松人工林的生长进程,从而得出结论:油松天然落种、自然出苗能力很强,只要条件具备,就能实现天然更新;依靠天然更新形成新的油松林林地生产力得到较大的提高。 相似文献
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对化香植被的人工促进天然更新技术作了初步研究,结果表明,人工促进对化香天然更新的效果是明显的,4a后其密度达3.7株/m2,分别为1999年、2000年和2001年对照的205.2%、185.7%和168.2%;高生长1999年较对照增加9.1%,2000年为对照的187.8%,2001年为对照的197.8%;在郁闭度方面,次年即达0.6,第3年达0.85,至第4年则达0.9,基本实现对林地的全面覆盖.人工促进天然更新第4年化香林地的生物总量分别为枫香林的488.7%、灌木丛的227.0%和湿地松林的92%,人工促进天然更新化香林地的生物总量与4年生湿地松生物差异总量不大,其生物、生态效益已与4年生郁闭湿地松林相似. 相似文献
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本文通过对天柱县1999、2000年度天保工程封山育林情况的调查分析：基于本地区丰富的水热、物种资源条件和独特的自然地理，封山育林作为保护和恢复森林资源的主要工程措施效果显著，值得推广。项目建设应选择栎类、马尾松、杂阔等先锋乔木为主要组成树种的疏林地和灌木林地作为封育对象。在天然林资源保护工程建设中，森林三大效益能否达到和谐统一，有待进一步研究。 相似文献
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对安宁市集体林权制度改革后林地管理工作的思考 总被引：2，自引：1，他引：1
由于安宁市林地管理采取集体统一和模式化管理的形式以及集体林权制度改革后均山到户,给林地管理工作带来了一些新问题,加大了对林地监管的难度.文中分析了林改后林地管理中凸现的实际权利不到位,林权流转平台尚未完善,林农主体地位得不到兑现,林权纠纷解决机制不完善,管理队伍不健全等问题.藉此,提出稳定林权,还权于民,规范林权流转机制,完善林业纠纷解决机制,依法依规保护管理林地,明确管理责任等加强林地管理的措施. 相似文献
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1998－2004年,贵州省黔东南州林地资源大量流失和有林地大量逆转的情况十分严重,有6725．34hm^2的有林地因改变用途或占用征用转为非林地,林地资源管理工作面临着严峻的考验。分析了当前林地资源监督管理中存在的一些突出问题,并提出对策及建议。 相似文献
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Teresa E. Gimeno Beatriz Pías Jesús Martínez-Fernández David L. Quiroga Adrián Escudero Fernando Valladares 《European Journal of Forest Research》2012,131(4):977-987
World-wide deforestation is being reversed in Mediterranean continental areas, where abandonment of traditional practises favours the expansion of valuable habitats, like Juniperus thurifera woodlands. We hypothesised that pre-existing trees facilitate establishment in expanding woodlands, whereas in mature woodlands, competition leads to patch disaggregation. We compared the imprint of these processes on growth, demographic and spatial structure of expanding and mature J. thurifera woodlands. We selected plots where we geopositioned, aged and quantified the morphological characteristics of all trees. In the mature woodland, trees arranged in clumps and randomly in the expanding woodland. Competition negatively affected growth, was greater in the mature woodland and led to disaggregation of juvenile clumps. Differences in growth between the mature and the expanding woodland disappeared in climatically unfavourable years, suggesting that adverse climate constrains growth more in expanding than in mature woodlands. We suggest that change in the dispersal agents and a decrease of facilitation underlay differences in spatial patters between the expanding and the mature woodland. Observed effective recruitment in less than 30?years into the expanding woodland evidenced that propagule arrival and sapling survival do not constrain woodland expansion. Furthermore, growth of juveniles established in these new areas is favoured by reduced intra-specific competition. However, we expect growth in expanding woodlands to be negatively impacted by climate change. We conclude that under current global change scenario, conservation of J. thurifera woodlands is favoured by changes in land use, but greater frequency and severity of drier than usual episodes could hamper natural reforestation. 相似文献
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Species distributions are determined by complex interplays between multi-scale factors. Conservation management, however, often occurs at a single scale of the site level. This is true for bird communities of restored savannas and mixed woodlands in the central U.S. In this region, many historic open-canopy oak savanna habitats have become closed canopy mixed woodlands due to loss of landscape-scale disturbance from fire and grazing. Site-level management efforts return some mixed woodland habitats back to savanna through fire and mechanical thinning. Savanna and woodland historically formed complex mosaic landscapes at the ecotone between prairies and Eastern deciduous forests and now exist within landscapes that vary in amount of open (e.g., perennial grassland and row crop agriculture) and woodland habitat. To understand the interplay between site and landscape level factors in savanna restoration, we sampled the breeding bird community in four combinations of site and landscape: restored savanna in open landscapes, restored savanna in woodland landscapes, and closed canopy woodland in both landscapes. We found that the outcome of site-level savanna restoration depended on the surrounding landscape. Compared to other treatment types, restored savannas in open landscapes supported a distinctive bird community characterized by high species richness, bird abundance, and percent of ground feeders, shrub nesters, and edge species. Both savanna and woodland sites in the open landscape had a higher percent of species of conservation concern, while at both site and landscape levels, woodland was associated with a higher percent of area sensitive species and habitat specialists. Our results suggest savanna restoration efforts should focus on sites that exist either in open country or on edges where closed canopy forest meets open country. This strategy would combine site and landscape level benefits of savanna restoration for avian diversity, while also preserving the conservation benefits of large tracts of intact forest. 相似文献