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在石灰岩中山区的干旱阳坡使用吸水剂进行造林的试验表明,使用吸水剂配成泥浆沾根及在造林穴中预先施入吸水剂都会提高油松苗木的成活率和生长量,尤其以沾根处理更为明显,是本区进行油松裸根苗造林时值得使用的一种方法。 相似文献
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使用高效吸水剂，菌根菌蘸根，ＡＢＴ生根粉Ⅲ号，根宝Ⅱ号浸根进行落叶松造林试验，其结果表明，用上述药菌浸根造林可以提高成活率，提高地径及高生长，经济效益显著。其中尤以ＡＢＴ生根粉Ⅲ号和根宝Ⅱ号效果为佳，适合我地区推广使用。 相似文献
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石质山地干旱阳坡造林技术研究 总被引：1，自引：0，他引：1
据承德县１０年来试验研究结果表明，对石质山地干旱阳坡采取抗旱造林技术是提高干旱阳坡造林效果的唯一途径。根据当地不同立地条件选择耐干旱树种，采用塑料薄膜覆盖，营养杯育苗造林，高分子吸水剂等综合抗旱技术措施，其效果更佳。一般处理比对照提高成活率７．０２％，最高达２４．６％。 相似文献
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栓皮栎是北京地区干旱阳坡比较好的造林树种。为了提高直播造林成活率,1965年我们选在阳坡、半阳坡作了低穴浅播和坐水浅播试验。试验证明,低穴浅播省工、成活率高。后来又发展成低穴浅播覆草圈的方法,成苗效果 相似文献
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吸水剂抗旱造林操作技术要点 总被引：5，自引：0，他引：5
如何有效地提高干旱地区的造林成活率和保存率,是众多的林业科技工作者长期以来一直在探索的一个难题。北京林业大学王九龄等同志在这方面的研究上已经取得了突破性进展。他们从1983至1987年在北京地区的低山阳坡进行了五年的抗旱造林试验,在气候和土壤极度干旱的条件下,利用吸水剂人为地在苗木根际处创造一个局部的湿润环境,从而使干旱阳坡的针叶树种造林成活率由过去的30%提高到80—90%,不仅为干旱地区造林开辟了一条新途径,也有效地解决了大苗上山和春季造林问题。此外,他们还较系统和全面地研究了吸水剂和混剂土壤的特性以及用吸水剂造林的操作方法,为吸水剂的合理使用提供了理论依据和具体措施。我们认为,这一研究成果起点高,方法先进,具有较高的实用价值,可以在广大干旱地区推广应用。现在,把利用吸水剂造林的操作技术要点介绍给读者,希望通过大家的努力,使其逐步完善。 相似文献
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吸水剂在造林中的应用效果试验 总被引：1，自引：0，他引：1
吸水剂处理过的苗木 ,其浓度为 1.5 %的处理效果最好 ,其平均成活率为 90 .0 3% ,平均比对照高了 8.2 3% ,最高可达到 13.7%。其各处理树种成活率由高到低分别为杨树 >香樟 >大叶女贞 >花椒 >对照。在土壤含水量上 ,每穴 5克拌土型吸水剂最大持水量为 12 6 .16 % ,浓度为2 %的博亚蘸根型吸水剂最大持水量为 76 .33% ,而对照仅为 5 1.1%吸水剂。在我省干旱地带利用吸水剂造林 ,对提高苗木成活率具有显著效果 相似文献
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檫木在东南沿海地区常规造林成活率偏低,对檫木裸根苗进行截干造林试验,结果表明:造林前两年檫木截干与未截干造林在成活率和地径、树高、抽高等生长量指标除了在第二年树高差异为显著水平外,其他指标在年度、性状间均为极显著差异;截干造林明显提高檫木造林成活率,造林第一年成活率100%,第二年成活率98%,两年生时截干造林成活率比未截干造林提高30.15%;明显促进地径生长,地径年生长量29%以上;大幅度提高抽梢生长量,第一年增幅222.78%,第二年增幅94.49%,檫木截干造林在东南沿海地区效果明显,是值得推广的造林方法。 相似文献
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本文主要对油松坐水覆膜造林进行试验,结果表明：坐水覆膜与对照相比,土壤的相对含水量提高2．38个百分点,地温提高0．7～1．6℃,油松造林成活率提高17个百分点,生长量提高16．5个百分点。因此,坐水覆膜在干旱、半干旱地区造林具有重要的意义。 相似文献
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对太行山石灰岩区干旱阳坡引种了11a的樟子松的生长、开花结实及其对土壤的改良效果、水保效益进行了分析,结果表明,引种的樟子松比相同立地条件下同龄油松的树高平均提高了28.60%,地径平均提高了8.20%,林地持水量提高了23.9%。实践证明,樟子松是适宜在太行山阳坡生长的优良水土保持树种。 相似文献
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Any Mary Petri?an Burghard von Lüpke Ion Catalin Petri?an 《European Journal of Forest Research》2009,128(1):61-74
In a field study, we measured saplings of beech, ash and maple growing in a fairly even-aged mixed-species thicket established
by natural regeneration beneath a patchy shelterwood canopy with 3–60% of above canopy radiation reaching the saplings. Under
low light conditions, maple and ash showed a slight lead in recent annual length increment compared with beech. With increasing
light, ash and maple constantly gained superiority in length increment, whereas beech approached an asymptotic value above
35% light. A suite of architectural and leaf morphological attributes indicated a more pronounced ability of beech to adapt
to shade than ash and maple. Beech displayed its leaves along the entire tree height (with a concentration in the middle crown),
yielding a higher live crown ratio than ash and maple. It allocated biomass preferentially to radial growth which resulted
in low height to diameter ratios, and expressed marked plagiotropic growth in shade indicating a horizontal light-foraging
strategy. In addition, beech exhibited the highest specific leaf area, a greater total leaf area per unit tree height, a slightly
greater leaf area index, and a greater plasticity to light in total leaf area. Ash and maple presented a “gap species” growth
strategy, characterized by a marked and constant response in growth rates to increasing light and an inability to strongly
reduce their growth rates in deep shade. In shade, they showed some plasticity in displaying most of their leaf area at the
top of the crown to minimize self-shading and to enhance light interception. Through this, particularly, maple developed an
“umbrella” like crown. These species-specific responses may be used for controlling the development of mixed-species regeneration
in shelterwood systems. 相似文献
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在青海省循化县通过对大果沙棘实生苗进行二因素四水平的氮、磷肥配合施用试验,结果表明：大果沙棘向阳品种的株高、根径和根长随着过磷酸钙、尿素的施用量的增加而增加,在过磷酸钙400kg·hm^-2,尿素150kg·hm^-2以时,株高、根茎和根长均达到最大值,之后随着过磷酸钙、尿素的施用量的增加,株高、根茎和根长增加缓慢或下降。过磷酸钙400kg·hm^-2,尿素150kg·hm^-2是向阳大果沙棘最佳基肥配比施用量。 相似文献
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重点分析了石漠化的主要成因、过程及环境效应.针对干旱、半干旱地区土地粗化和贫瘠化,生产潜力和生物产量、数量下降以及地质特点等,通过样地治理比较分析,提出了以生态修复为主,工程治理及移民搬迁为辅,调整产业结构的治理方针,进一步探索了石漠化治理模式. 相似文献
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根据样地调查、解析木和气象资料,拟合了晋西刺槐(Robinia pseudoacacia Linn.)人工林基于耗水量的幂函数密度调控模型。其中,以单株材积连年生长量和单株胸径连年生长量表示的模型拟合效果较好。研究表明,干旱、半干旱区有必要在传统密度控制图基础上,以水分资源环境容量为基点,以不同林龄水分消耗与降水资源平衡原则,制定基于降水量的不同林龄林分密度控制图。 相似文献
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杨树丰产林伐桩嫁接技术研究 总被引：1，自引：0，他引：1
针对山西省北部大面积杨树成过熟林分亟需更新改造的现状,提出了改造的新模式。确定杨树良种＂中金杨＂和白杨派新品种为换代品种。在伐桩嫁接更新改造中采用湿土堆埋法,再进行塑料薄膜覆盖,可缩短出苗期,提高当年高生长量和胸径生长量,减少除萌次数,成活率达到91%以上;成活植株产生自生根系,嫁接3 a留有自生根4条～7条,根径1.2 cm～2.4 cm,生长正常。＂中金杨＂和白杨派新品种树高和胸径的4龄指标均超过三根二干＂中金杨＂植生苗和萌生苗的生长量。 相似文献
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Field measurements were made of leaf photosynthesis (A), stomatal conductance (g) and leaf water relations for sugar maple (Acer saccharum Marsh.) seedlings growing in a forest understory, small gap or large clearing habitat in southwestern Wisconsin, USA. Predawn water status, leaf gas exchange and plasticity in field and laboratory water relations characteristics were compared among contrasting light environments in a wet year (1987) and a dry year (1988) to evaluate possible interactions between light and water availability in these habitats. Leaf water potentials (Psi(leaf)) at predawn and midday were lower for clearing than gap or understory seedlings. Acclimation of tissue osmotic potentials to light environment was observed among habitats but did not occur within any of the habitats in response to prolonged drought. During a summer drought in 1988, decreases in daily maximum g (g(max)) and maximum A (A(max)) in clearing seedlings were correlated with predawn Psi(leaf), which reached a seasonal minimum of -2.0 MPa. Under well-watered conditions, diurnal fluctuations in Psi(leaf) of up to 2.0 MPa in clearing seedlings occurred along with large midday depressions of A and g. In a wet year, strong stomatal responses to leaf-to-air vapor pressure difference (VPD) in sunny habitats were observed over nine diurnal courses of gas exchange measurements on seedlings in a gap and a clearing. Increasing stomatal limitations to photosynthesis appeared to be responsible for the reduction in A at high VPD for clearing seedlings. In understory seedlings, however, low water-use efficiency and development of leaf water deficits in sunflecks was related to reduced stomatal limitations to photosynthesis relative to seedlings in sunny habitats. Predawn Psi(leaf) and VPD appear to be important factors limiting carbon assimilation in sugar maple seedlings in light-saturating irradiances, primarily through stomatal closure. The overall results are consistent with the idea that sugar maple seedlings exhibit "conservative" water use patterns and have low drought tolerance. Leaf water relations and patterns of water use should be considered in studies of acclimation and species photosynthetic performance in contrasting light environments. 相似文献