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1.
Nursery seedbeds sown with lodgepole pine, Scots pine, Douglasfir, Japanese larch and Sitka spruce were covered with clearpolythene cloches for 0, 8, 13 or 18 weeks from sowing. Sitkaspruce germinated poorly and was not studied further. In bothpine species longer durations of cloche cover increased thenumber and length of stem units resulting in taller 1 + 0 seedlings.The number of internodes held at the apex for elongation inthe second season was also increased but transplant shock preventedfull expression of this potential such that differences betweenthe treatments were reduced. Only when covered for 18 weeksdid Douglas fir and Japanese larch produce 1 + 0 seedlings whichwere taller than the uncovered treatments. Through the productionof ‘summer shoots’ in their second season Douglasfir and Japanese larch were able to compensate partially forthe reduction in ‘spring shoot’ length caused bytransplanting.  相似文献   

2.
THOMPSON  DONALD A. 《Forestry》1984,57(1):1-16
An experiment in Helmsdale Forest (Highland Region, Scotland)examined the effects of shelter and weed competition on Sitkaspruce (Picea sitchensis (Bong.) Can.) and lodgepole pine (Pinuscontorta Douglas ex Loudon). Different levels of shelter fromwind were achieved by using netting and were measured usingtatter flags. Three treatments compared weed competition byremoving no vegetation, heather (Calluna vulgaris L.) only orall ground vegetation respectively. Results indicate a definiterelationship between material lost from tatter flags and treedry weight at five years. Even the smallest increase in shelterresulted in increased growth of Sitka spruce and the beneficialeffect of shelter became most apparent 4 to 5 years after planting.Tree dry weight was found to be correlated with root collardiameter and height but not fifth year height increment. Resultsfrom weeding treatments were unclear and differed between species.This was because bird damage interacted with weeding, the completelyweeded plots being most heavily damaged; and because the methodof hand weeding (pulling out the whole plant including roots)damaged fine tree roots. Bird damage was prevented by nettingbut in unnetted plots it was found impossible to separate birddamage from other factors although it was clearly more seriouson lodgepole pine.  相似文献   

3.
MASON  W. L.; BIGGIN  P. 《Forestry》1988,61(2):149-163
Seedlings of Sitka spruce and Lodgepole pine were grown in fivedifferent container types; Ontario tubes, Kopparfors multipots,Finn peat pots, Japanese paperpots and Spencer-Lemaire root-trainers.They were planted in forest experiments in 1972/3 when 8-14weeks old and their subsequent performance compared with 2 years-oldbare-rooted transplants. After 2–3 years' growth, tubed seedlings proved consistentlypoorer than all other treatments for both height and survival.Finn peat pots were marginally the best of the other containerstested. Containerised plants generally showed poorer survivaland substantially less height growth than transplants, withdifferences being greater for Sitka spruce than for Lodgepolepine. For both species well-handled transplants appear the mostappropriate plant type for use in upland Britain. Implications for the future role of containerised seedlingsin upland forestry in Britain are considered. The benefits ofcontainer systems may be greatest in the production of seedlingsof ‘sensitive’ species or of high genetic quality.  相似文献   

4.

The effect of site fertility, spacing and mode of regeneration on the survival and stand development of lodgepole pine, Scots pine and Norway spruce was studied in a series of experiments comprising 22 study areas in Finland. After 13-14 yrs, lodgepole pine had a mean survival of 68% in planted and 61% in seeded plots, while Norway spruce had the highest (92%) and Scots pine the second highest survival (82%). The survival of planted lodgepole pine was better the wider the spacing. Best survival was achieved on subdry and dry sites, both with planting and with direct seeding. Dominant height was not affected by spacing, but both basal area and volume at the age of 13-14 yrs were significantly higher the denser the spacing. The average difference in the value of the estimated site index H 50 was slightly under 3 m for the superiority of lodgepole compared with Scots pine. Seeding resulted in site indices almost as high as those of lodgepole planting.  相似文献   

5.
McINTOSH  R. 《Forestry》1982,55(1):61-68
Application of four forms of nitrogen fertilizer each at threerates produced significant positive responses in shoot growthin a seven-year-old Pinus contorta, Dougl. stand on a deep,infertile peat in south Scotland. The response was shortlived(4 years) and was followed by a period (1–2 years) whenshoot growth fell below the control level. Form of N did notaffect the result but rate of N did and these effects are discussedwith respect to annual shoot growth, foliar N levels and shootgrowth:foliar N correlations.  相似文献   

6.
BRITTON  R. J. 《Forestry》1988,61(2):165-175
Field experiments involving naturally occurring population levelsof larval European pine sawfly Neodiprion sertifer (Geoff. )and artificial defoliation in both field and glasshouse experimentswere used to investigate physiological effects of defoliationon lodgepole pine. Reductions in total projected leaf area,annual height and volume increments of 19, 33 and 32 per cent,respectively, were recorded on trees where larvae had consumedall mature foliage. Leader growth was up to 48 per cent lesson defoliated trees after two years reflecting a delayed growthimpact. Similar effects were found on trees which had been defoliatedby hand in a manner resembling sawfly feeding. Artificial defoliationof transplants also showed that this type of damage can haveserious consequences on below-ground growth, particularly offine roots. Root:shoot ratios were found to be 0.64 in undamagedplants and 1. 05 in defoliated plants. A high concentration(1300 ppm) of the insecticide fenitrothion, used to maintaincontrol treatments in the field, was found to have no significanteffects on the major growth parameters being assessed.  相似文献   

7.
当年生华北落叶松幼苗的耐旱性   总被引:1,自引:0,他引:1  
  相似文献   

8.
THOMPSON  J.H.; MAYHEAD  G.J. 《Forestry》1982,55(2):173-182
Experimental plots in young plantations of Sitka spruce andlodgepole pine were over-dosed with five granular herbicidesto ascertain the margin of crop safety involved in the use ofpropyzamide, chlorthiamid, dichlobenil, dichlobenil/dalaponmix and atrazine. It is concluded that if the five herbicidesare applied according to the standard rates and dates used inthe experiments, tree damage will be kept to an acceptable minimum.Better shoot growth resulted from herbicide treatment than fromhand weeding particularly where atrazine was used.  相似文献   

9.
马尾松(Pinus massoniana)和湿地松(Pinus elliottii)苗根系感染彩色豆马勃(Pisolithus tinctorius)菌株形成菌根后,对苗木的高、地径和侧根生长均存在显著的促进作用。但不同的接种方法,存在一定的差异,其中A处理(点穴式接种)的感染率最高,马尾松苗69.4%,湿地松苗61.7%;D处理(拌土接种式)的最低,分别是27.2%和43.1%。与对照相比,A处理马尾松和湿地松苗高分别增加20.1%和32.0%;地径分别大24.0%和29.0%;侧根数量分别多79.6%和55.8%;而D处理苗高分别增加8.0%和3.8%,地径分别大4.0%和16.1%,侧根数量分别多12.3%和29.3%。  相似文献   

10.
In the article, with the instruments of the Research Institute of Wood Industry, Chinese Academy of Forestry, the experiment method of Forintek Canada Corp. was used to test the laminating of lodgepole pine containing beetle-transmitted bluestain; finally the result was compared with Canada report. The results show that the presence of glue joints of bluestained wood made with either PVA or PRF adhesive makes no difference to the shear strength of the joints, and no difference to durability of the joints using PRF. Also the presence of beetle-transmitted bluestain in wood does not affect the adherence of the interior finishes tested.  相似文献   

11.
土壤益生菌对盆栽马尾松苗生长的影响   总被引:1,自引:0,他引:1  
将固氮菌、解磷菌、解钾菌按不同组合接种到盆栽的马尾松幼苗根部,结果表明:2号固氮菌 解磷菌组合处理的苗木高生长比对照增长11.6%;2号固氮菌处理的苗木地径生长比对照增长23.3%;两种固氮菌 解磷菌 解钾菌组合处理的苗木生物量分别比对照增长45.5%和48.8%。而土壤中的N、P、K元素的含量也发生了明显的变化,1号固氮菌则使土壤含氮量增加54.2%,其它处理均使土壤含氮量减少。可溶性磷增加20.0%~50.0%,可溶性钾增加144.4%~277.8%。  相似文献   

12.
ROCHE  L. 《Forestry》1966,39(1):30-39
Variation in growth habit and bark type of lodgepole pine (Pinuscontorta Douglas) in its native habitat is described and illustratedwith photographs. Needle morphology is assessed from plantationsamples and some of the problems associated with the assessmentof variation are discussed. The problem of ensuring that importedseed is collected from the right stands is considered.  相似文献   

13.
HAYES  A. J. 《Forestry》1975,48(1):99-113
Experimental inoculations of C. sororia on un-wounded Lodgepolepine produced successful infections after 9 months in 25 percent of cases, compared with 40–60 per cent where woundswere inoculated. After 16 months, however, these differencesdisappeared. The virulence of different isolates of C. sororiadiffered. Current year's shoots were more resistant to infectionthan 1-year-old shoots. Resistance was generally not a functionof broad geographical origin, save in the southern coastal types.Some provenances were highly significantly more susceptiblethan other closely adjacent ones: Burns Lake and Salmon Armwere highly susceptible, whereas Fort St. James and Mount Idaprovenances were respectively resistant. These observationsagree closely with field survey data, thus validating the useof young plants to indicate resistance of older crops to infection.  相似文献   

14.
为了探讨氮肥对松树苗木生长的影响,以油松和樟子松为试验材料,对这2种松树的高度和生物量的变化及转移情况进行研究。结果表明:施用氮肥对油松和樟子松高度的生长有显著影响,依次为高氮中氮低氮;低氮肥处理的地上生物量最高,中肥和高肥处理的生物量向根系转移量降低,3种施肥处理均以高氮量处理生物量最低。  相似文献   

15.
对云南省德宏州、普洱市选出的西南桦优树进行组培,培育出4个无性系苗木,以普洱无性系为对照,开展西南桦的山地造林试验,每月定时观察记录,并进行分析。分析结果表明:4个无性系幼树的1年树高、径粗生长呈现为生长缓慢期、速生期、缓慢期3个阶段,生长高峰集中在5~8月;西南桦无性系2号与其它3个无性系之间达到极显著差异,生长最快,适应性强,可作为普洱当地造林的候选优良繁殖材料进一步试验观测。  相似文献   

16.
火炬松(Pinux taeda L.)和湿地松(Pinus elliottii Engelm)是我国南方重要的外引用材树种,经过多年的试验研究,已选出一批较好的种源、家系和单株,并建立了种子园。当前早期鉴定和早期选择已成为必不可少的一项研究内容,近几年来越来越多的研究者指出,林木幼龄期的某些性状或生理生化指标与成熟期性状之间存在一定的相关性,认为树木生长的早期选择是可能的,尤其从生理生化方面来探索林木早期预测的研究已引起人们的高度重视。但  相似文献   

17.
Rates of mineral nitrogen production and carbon dioxide evolutionin incubated samples from the upper 300mm of peat beneath lodgepolepine (Pinus contorta Dougl.) have been compared with those foradjacent unplanted areas at each of six sites in the North ofScotland. Under both aerobic (moist) and anaerobic (water logged)conditions, rates of mineral nitrogen production at 30°Care strongly influenced by peatland type, sampling depth andafforestation. During the early stages of the incubation underaerobic conditions, samples of planted peat showed a more rapidaccumulation of mineral nitrogen than did samples from unplantedareas, the amounts after 17 days being 170ppm and 46ppm mineralN, respectively; after 62 days however, the difference was nolonger significant. The mean rate of CO2 production averaged446µg CO2 g–1 day–1 in planted as against728µg in unplanted peat. Under anaerobic conditions, amountsof mineral nitrogen accumulated were similar in planted andunplanted sites but a difference in accumulation between the0–150 and 150–300mm horizons in unplanted peat wassignificantly reduced beneath the trees.  相似文献   

18.
几种外生菌根菌对松苗抗非根部病害的影响   总被引:5,自引:0,他引:5  
研究几种外生菌根真菌对松苗抗松枯梢病和抗松材线虫病的影响.结果表明:菌根菌增强了马尾松苗苗木对松枯梢病的抵抗力,其中华美牛肝菌(504)菌根苗的抗性最强,其次为黄豹斑鹅膏(EG)和彩色豆马勃Pt2菌根苗,彩色豆马勃Pt,和紫金蜡蘑(ZJ)菌根苗的抗性相对较弱;但外生菌根菌对湿地松苗苗木抗松枯梢病的能力未见提高.对黑松和马尾松菌根苗接种松材线虫后发现,菌根增强了黑松和马尾松对松材线虫病的抵抗力,延缓或减轻了苗木的死亡,以504、Pt2和EG的效果较好.黑松菌根苗接种松材线虫后各处理体内早期的PAL活性存在一定差异.对松材线虫抗性较强的菌根苗其体内PAL酶活也较高,反之亦然.供试外生菌根菌的促生作用以及菌根苗体内抗病代谢酶活性的变化与其抗病性有一定的相关性.  相似文献   

19.
小叶锦鸡儿1年生播种苗的生长规律   总被引:1,自引:0,他引:1  
小叶锦鸡儿1年生播种苗苗高、地径的生长变化及生物量组分分配模式的研究结果表明,苗高、地径的生长规律符合S形生长曲线,可用Logistic方程拟合,整个生长期可划分为4个阶段,即出苗期、生长初期、生长盛期和生长后期,其中生长盛期苗高、地径的生长量分别占年生长量的63.7%和54.5%。小叶锦鸡儿播种苗根、茎、叶的生物量分配比例为:23.8:25.2:51.0,地下部分与地上部分生物量之比(R/T)为0.312。苗高、地径与生物量呈线性相关。且地径与地上部分生物量和总生物量的相关系数分别大于苗高与两者的相关系数。  相似文献   

20.
湿地松人工林生长规律   总被引:1,自引:0,他引:1  
采用连续测定资料,分析了广西华山林场11年生湿地松(Pinus ellottii)松脂原料林的生长过程及林分结构。结果表明:湿地松胸径生长高峰出现在第3年,6年生前为速生期,随后胸径生长量快速下降;胸径分布随年龄的增加由左偏逐步转为右偏,在6年生时趋于正态分布;林分树高连年生长量波动大,无明显变化规律,连年生长量均值为0.62 m,8年生前为速生期,树高分布为右偏,优势木相对较少,林相较为整齐;自然整枝在8年生时最强烈,枝下高年上升1.20 m,适宜在7年生时进行适当修枝间伐抚育;单株材积生长率在11年前均大于10%,处于速生期。湿地松在该试验区适应性良好,若以8.0、10.0、12.0 cm作为最小起始采脂胸径,则在湿地松林分5~6年生、7~8年生或11年生以后采脂即可获得较高的利用率。  相似文献   

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