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林分密度对油松中龄林生长特征的影响 总被引：1，自引：0，他引：1
《山西林业科技》2015,(1)
以平顺县和太原东山25年生的油松人工林为调查对象,通过样地调查,研究林分密度对树高、胸径、枝下高和冠幅等生长特征的影响,以及生长特征指标之间的相互影响。结果表明,林分密度对树高无显著影响,枝下高随林分密度的增大而增大,冠幅、胸径均与林分密度呈显著负相关关系;林分密度为950株/hm2时,树高、胸径、枝下高和冠幅之间相关性均不显著;林分密度为3 050株/hm2时,胸径与树高、胸径与冠幅、冠幅与枝下高显著相关;林分密度为5 600株/hm2时,胸径与树高、冠幅、枝下高,树高与冠幅、枝下高及冠幅与枝下高间均显著相关。 相似文献
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湿地松加勒比松杂交组合引种试验研究 总被引：8，自引：3，他引：8
通过对湿地松、加勒比松杂交组合引种试验研究表明:在生长性状树高、胸径、材积、侧枝总数方面,杂交组合普遍好于对照;在生长性状冠幅方面大部分杂交组合种好于湿地松无性系种子园混合种、加勒比松无性系种子园混合种,少部分比当地马尾松好;在生长性状方面杂交组合间和杂交组合内存在差异。主要生长性状树高、胸径、材积存在极显著相关,因此间接选择也是有效的。在抗寒性方面,加勒比松无性系自由授粉子代、加勒比松无性系种子园混合种CK2抗寒性最差,湿地松无性系种子园混合种抗寒能力较强,没有受冻,加勒比松无性系种子园混合种CK3、当地马尾松、杂交组合种较抗寒且抗寒性相近;在抗虫(松梢螟)性方面无显著差异。 相似文献
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《山西林业科技》2017,(4)
以关帝山国有林场30年生华北落叶松人工林为研究对象,通过标准地调查,研究华北落叶松人工林林分生长因子与林分密度的相关性。结果表明,林分密度对胸径、树高、冠幅、枝下高均有一定程度的影响。枝下高随林分密度的增大而增加,树高有微弱增大的趋势,而冠幅、胸径均与林分密度呈显著负相关关系;林分密度为200株/hm2时,胸径与树高、冠幅显著相关,胸径、树高、冠幅和枝下高之间均不存在显著相关关系;林分密度为725株/hm2时,树高、胸径、枝下高和冠幅各生长因子间均不存在显著的相关关系;林分密度为1 400株/hm2时,胸径与树高极显著相关,胸径与冠幅,胸径与枝下高,树高与冠幅、枝下高,枝下高与冠幅间不存在显著的相关关系。 相似文献
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湿地松×洪都拉斯加勒比松F1杂种的多性状综合评价 总被引：1，自引：0，他引：1
根据1块种植于广东省台山市红岭种子园的湿地松×洪都拉斯加勒比松F1杂种测定林的7年生数据,就杂种的生长量、树干通直度、分枝习性与湿地松、加勒比松进行了比较分析。结果表明,F1杂种的生长优势突出,树高、胸径、材积分别为9．18m、14．96cm、0．08645m^3,相对于湿地松、洪都拉斯加勒比松和古巴加勒比松种子园混合种的材积现实增益分别为315．23％、46．35％、114．89％。此外,杂种的树干通直度得分、冠幅、枝角、枝径、枝数分别为1．54分、3．45m、68．93°、1．84am、3．35条,其树干通直度得分与母本湿地松接近而显著低于父本洪都拉斯加勒比松,冠幅和枝径与父本相似而显著大于母本,枝角介于父、母本之间,枝数与父、母本没有显著差异。 相似文献
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湿地松、加勒比松人工林优树选择研究 总被引：1，自引：1，他引：0
以树高、胸径、材积为生长量指标,结合干形、冠幅、皮厚等形质指标,采用5株优势木对比法对40 a生湿地松(Pinus elliottii)、13~40 a生加勒比松(P. caribaea) 人工林开展优树选择研究,提出优树选择标准。40 a生湿地松优树树高、胸径、单株材积分别大于5株优势木平均值的1%、15%、35%以上,树干通直,共选择出优树10株,入选率为 4348%。13～40 a生加勒比松优树树高、胸径、单株材积分别比5株优势木平均值大8%～12%、15%～22%、49%～70%,树干通直,共选择出优树77株,入选率为 4919%。湿地松、加勒比松优树选择应以生长性状为主要目标,同时注重木材密度、产脂等性状的选择,进而丰富其育种群体的遗传多样性。 相似文献
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根据1块种植于广东省台山市红岭种子园的湿地松×洪都拉斯加勒比松F1杂种测定林的7年生数据,就杂种的生长量、树干通直度、分枝习性与湿地松、加勒比松进行了比较分析。结果表明,F1杂种的生长优势突出,树高、胸径、材积分别为9．18m、14．96cm、0．08645m^3,相对于湿地松、洪都拉斯加勒比松和古巴加勒比松种子园混合种的材积现实增益分别为315．23％、46．35％、114．89％。此外,杂种的树干通直度得分、冠幅、枝角、枝径、枝数分别为1．54分、3．45m、68．93°、1．84am、3．35条,其树干通直度得分与母本湿地松接近而显著低于父本洪都拉斯加勒比松,冠幅和枝径与父本相似而显著大于母本,枝角介于父、母本之间,枝数与父、母本没有显著差异。 相似文献
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Liu HuirongNortheast Forestry University 《林业研究》1993,4(2):11-17
The plantations of korean pine(Pinus koraensis)and scots pine(Pinus sylvesrisvar.mongolica)are mainly pure stands.Fires are gradually causing problems in theseplantations and being paid much more attention recently.Study on the influence of fire ontrees and the adaptation to fire,therefore,is of great important to probe the fire ecologicalproperties and the protection ways of these two species.The results are as follows:Bothof the species are easily damaged by fire,but korean pine is more susceptible.In the samefire,korean pine is damaged more seriously than scots pine although they have the samesize.Young individuals have low fire resistant capacity and can be damaged seriously,andolder ones have strong fire resistance and can be damaged lightly.Up-hill fire makes aserious damage to the trees distributed in up-slopes with the reason of higher fireintensity.Down-hill fire makes a serious damage to the trees distributed in down-slopcswith the reason of higher fire severity.The larger deocambium area in t 相似文献
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In response to concerns about aluminum and HCl exposure associated with rocket motor testing and launches, survival and growth of full-sib families of loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii Engelm.) were evaluated in a nursery bed experiment. Each species was exposed to a single soil application of aluminum chloride (0.33 M AlCl(3), pH 2.5), hydrochloric acid (0.39 M HCl, pH 0.6) or water, with or without mycorrhizal inoculation with Pisolithus tinctorius (Coker and Couch). After 20 weeks without inoculation, survival in AlCl(3) and HCl treatments averaged 52% for loblolly pine and 72% for slash pine. Inoculation improved survival of loblolly pine, receiving HCl from 49 to 73%, and of those receiving AlCl3, from 55 to 90%. Inoculation also resulted in improved survival and growth of individual families in AlCl(3), but not in HCl treatments. Results illustrate the relative resistance of both pine species to the acute treatments supplied, the improvement in resistance associated with mycorrhizal inoculation and the importance of field testing, following hydroponic screening, to verify the resistance to soil-supplied stresses. 相似文献
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Lili Zhang Zhenyu Li Hailin Li Ruidong Han Yongli Zhao 《Frontiers of Forestry in China》2006,1(4):453-459
Chinese pine caterpillar (Dendrolimus tabulaeformis) larvae were fed with pine needles of different degrees of damage to evaluate the effects of pine needles on the growth and
development of larvae. The results showed that the nutritional index of the larvae declines after feeding on the damaged pine
needlings. The lowest amount of food ingested and voided feces, the lowest nutritional index, slowest development, lightest
pupae and most mortality were found in those pine caterpillar larvae fed with pine needles which were 50% damaged. The damaged
pine needles significantly affected the population dynamics of Chinese pine caterpillars. The nutritional indices of larvae
fed with 25% and 75% damaged pine needles were similar. The nutritional index of the dark morphs was higher than that of the
tinted morphs, however, their mortality was lower than that of the tinted morphs. This phenomenon was reversed at the later
stage of development when the larvae were fed on 50% damaged pine needles.
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Translated from Journal of Beijing Forestry University, 2005, 27(6): 83–88 [译自: 北京林业大学学报, 2005, 27(6): 83–88] 相似文献
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Needle retention (number of needle sets), needle density, height increment and radial increment were surveyed on seven Japanese
black pines (Pinus thunbergii Parl.) and seven Japanese red pines (Pinus densiflora Sieb. et Zucc.) growing on the same site. Number of needle sets on branches with respect to whorl position was estimated
visually. In 1999, maximum summer needle retention was observed on the fifth and sixth whorl from the top, with values of
3.4 needle sets for the black pines and 2.4 needle sets for the red pines, respectively. The needle trace method (NTM) was
used to determine needle retention and needle density along the main stems retrospectively for the years 1968–1998. The long-term
mean summer needle retention along the main stem was 3.7 needle sets for the black pines and 2.2 needle sets for the red pines.
In both pine species, the number of needle sets varied from year to year. However, the long-term budget between newly born
and annually shed needle sets was in equilibrium. The long-term average of needle density per cm of stem shoot was 9.4 needle
pairs for the black pines and 7.4 needle pairs for the red pines. The results showed clear intra-specific and inter-specific
similarities in needle retention, height increment and radial increment trends. The values for number of needle sets, height
increment and radial increment positively increased with favorable growing conditions, whereas the value of needle density
had an opposite tendency. 相似文献
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To probe variation in Al sensitivity of two co-occurring pine species, seedlings from six full-sib families of loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii Engelm.) were grown in solution culture containing 4.4 mM (high-Al) or 0.01 mM (low-Al) AlCl(3) at pH 4 for 58 days. On average, both pine species had 41% less total dry weight in the high-Al treatment than in the low-Al treatment. Stem volume growth of slash pine was more sensitive to the high-Al treatment than that of loblolly pine. In both species, the high-Al treatment inhibited root dry weight more than shoot dry weight. Within-species variation in Al sensitivity among families was greater in loblolly pine (24 to 52% inhibition of seedling dry weight) than in slash pine (35 to 47% inhibition of seedling dry weight). Foliar Al concentration was positively correlated with Al sensitivity in slash pine but not in loblolly pine; however, in both species, the concentration of Al in roots was 20-fold greater than in foliage. 相似文献
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Three forest disturbance periods, 1973—present, 1922–1929, and 1827–1946 were determined by aging scars on stems of lodgepole pine trees. All of the scars from the 1970's and 1920's, and most of the scars from the 1820's–40's were determined to be caused by the mountain pine beetle. A few scars from the earliest period may be the result of fire. Diagnostic characteristics of beetle scars are: resemblance to fire scars, pitch tubes, beetle emergence holes, blue stain, beetle galleries, retained bark on the scar face, and an orange or red discoloration around healthy sapwood. Beetle attacks tend to have a northeastern aspect and extend approximately two-thirds around tree boles at breast height.By recognizing beetle scars it is possible to accurately age previous mountain pine beetle attacks. Many scars which had been thought to be of fire origin are actually caused by the mountain pine beetle. 相似文献
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Mature shrubs can provide microhabitats that are beneficial to tree seedling growth and development. Sugar pine trees (Pinus lambertiana) grow in a narrow zone on the eastern slope of the Carson Range in extreme western Nevada, whereas Jeffrey pine (Pinus jeffreyi) is the dominant tree species in the region, an area extensively disturbed by wild fire. This study compares seedling establishment of sugar pine and Jeffrey pine relative to mature shrubs. In the fall of 2002 (cohort 1) and 2003 (cohort 2), 13,600 seeds of both species were planted in wire mesh enclosures, at three sites, under a variety of microhabitat treatments: under shade and in the open, under two species of shrub cover, and with and without plant litter. Seedlings were monitored for survival through two growing seasons. Even though more sugar pine seedlings emerged, more Jeffrey pine seedlings survived, and Jeffrey pine was the more drought tolerant species, better suited for the xeric climate found in the Carson Range. Litter slightly hindered seedling emergence but had no effect on survival and there was no significant species × litter interaction. Supplemental water facilitated survival in all treatments with highest survival in shade treatments. Sugar pine seedlings showed a significant increase in survival over Jeffrey pine seedlings with the addition of water, particularly in open treatments and more of both species survived under manzanita shrubs with water. The highest seedling mortality occurred when shrub canopy was removed, and seedlings experienced the effect of full sun and competition for soil water. For either species, microhabitat is a significant factor in determining success or failure in rehabilitation efforts after disturbance. 相似文献
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In this study, the effect of pine mistletoe (Viscum album subsp. austriacum) on basal area increment of Crimean pine and Scots pine was investigated. Dendrochronological data were collected from 223 (71 uninfected and 152 infected) Crimean pines and 195 (77 uninfected and 118 infected) Scots pines located in Kastamonu province of Turkey in 2014. Infected sample trees were classified as light, moderate or severe infection levels. Growth trends and basal area increment loses were compared between uninfected and infected trees for the periods of the last 10, 20 and 30 years. In addition, infection status of forest stands was investigated using temporary sample plots; 27 plots in Crimean pine stands and 26 plots in Scots pine. Results demonstrated that basal area increments were negatively affected by pine mistletoe for both species. Mean basal area increment losses of infected trees for the last decade were determined as 24% for Scots pine and 26% for Crimean pine. Basal area increment losses varied by infection levels (light, moderate and severe) as follows: 25%, 20% and 28% for Scots pines and 20%, 32% and 9% for Crimean pines. Scots pine stands were more severely infected by pine mistletoe than Crimean pine stands. There were negative correlations between number of infected trees and stand density for both species, while positive correlation was detected between the number of infected trees and mean diameter for Scots pine. The results of this study indicate that the pine mistletoe infection has negative effect on radial growth of Scots pine and Crimean pine trees. The results can be an important contribution to the forest management and protection activities in mistletoe-infected stands. 相似文献
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E. Bilgili M. Ozturk K. A. Coskuner I. Baysal B. Serdar H. Yavuz M. Eroglu Y. Usta 《Forest Pathology》2018,48(4)
Mistletoe infection results in substantial growth losses in mistletoe‐infected forests. This study reports and evaluates the results of retrospective analyses of radial growth of Scots pine (Pinus sylvestris) in relation to the level of infection of pine mistletoe (Viscum album ssp. austriacum). A total of 43 Scots pine trees were destructively sampled from different sites. Of these trees, 14 were uninfected and 29 were infected. Infection classes were determined using six‐class dwarf mistletoe rating system (DMRS). All needle and mistletoe biomass were removed completely and weighed for each sampled tree. Subsamples from needles and all mistletoe biomass were taken to the laboratory for oven‐dried weight determinations. Five‐cm‐thick wood discs were cut from the stem at the breast height (1.3 m) to determine annual basal area increment for the last 25 years. In addition to DMRS, new infection classes were created using mistletoe‐to‐needle biomass (MB/NB) ratio. The results showed that the radial growth losses could be as much as 41% to 64% at different infection levels. The rate of growth loss in relation to DMRS and MB/NB ratio was similar, but with a larger variability in DMRS values. The results showed that both DMRS rating and MB/NB ratio seem to be important for quantifying growth loss on Scots pine trees infected with mistletoe. The results of this study can also be invaluable in modelling the effects of mistletoe on the growth of Scots pine trees. 相似文献