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1.
马占相思(Acaiamangiumwilld)为豆科速生阔叶树种。它具有生长迅速,适应性强,育苗造林容易,能固氮及改良土壤,产量高,轮伐期短,收益较快等优点,是造纸、拷胶、用材及造林绿化的优良树种。8-’10年轮伐,主伐每亩材积13m3~15m3。马占相思原产澳大利亚及巴布亚新几内亚,主要分布在南纬8°~18°,海拔300m以下。原产区属于热带湿润气候,最热月平均最高温度为引℃-34℃,最冷月平均最低温度为15℃~22℃。年降雨量15ho-3(XXXllzl。马占相思为低海拔树种,分布在丘陵、台地、低山及沿海背风地区。在表土层深厚、疏松、排水良…  相似文献   

2.
耐寒相思及其在闽北的引种前景   总被引:2,自引:0,他引:2  
原产澳大利亚的耐寒相思类树种生长快, 有根瘤, 具固氮作用, 可改良土壤, 木材用途广, 在闽北地区引种栽培有广阔的前景。  相似文献   

3.
相思类树种木材的资源、材性与加工利用   总被引:12,自引:0,他引:12  
相思类树种生长速度快,适应性强,在我国南方广泛引种栽培。通过对其木材的解剖特征、天然耐腐性、干燥特性、制浆造纸性能以及人造板和细木工等加工性能的分析,结果显示,相思类树种木材不但是优良的纸浆材原料之一,而且多数树种木材也是生产人造板和实木家具等的较好原料。  相似文献   

4.
马尖相思多点栽培试验阶段报告   总被引:1,自引:0,他引:1  
本文报道了在景洪、普文、思茅、河口、瑞丽5个地点所同时进行的马尖相思多点栽培试验2.5年生林分的测定结果。初步证实云南北热带及南亚热带南部。年均温18℃以上,≥10℃积温6300℃以上,年降水量1200mm以上,土壤pH值4-6,无霜或偶有轻霜的地区是马尖相思的适生区。在此区域内马尖相思表现出初期速生,年平均树高生长量达1.46-1.72m,胸径生长量1.17-1.53cm。育苗造林措施与幼林管理  相似文献   

5.
大叶相思(Acacia acuriculaelormi-s cunn)属含羞草科常绿乔木。原产泰国及澳大利亚。大叶相思根系发达,能固氮,可改良土壤;生长迅速,耐干旱瘠薄;木材坚韧,纹理细致,可作家具、建筑及造纸等用材;是热带、南亚热带地区低丘荒山绿化及营造混交林的一个好树种。  相似文献   

6.
厚荚相思的引种、生长、良种繁育及利用   总被引:3,自引:0,他引:3  
厚荚相思于1985年从澳大利亚引种,经多点引种试验表明:它可在我国热带及南亚热带沿海低海拔地区的低丘、低山、岗地及沙地,无霜冻或无严重台风处发展,它为浅根性树种;其生长与年均温密切相关,即在热带生长较南亚热带为快。在海南6年可果伐作纸浆材,每亩材积可达10m3;厚荚相思优良种源产自巴布亚。在海南临高3年始花,7年种子进入盛产期,每公顷可产种49-102公斤;厚芙相思硫酸盐浆可生产高质量文化用纸。  相似文献   

7.
10个相思类树种的生长比较与评价   总被引:2,自引:0,他引:2  
林榕庚 《广西林业科学》1995,24(1):18-20,29
本文通过对10个相思类树种的引种栽培试验进行总结,在生长比较与聚类分析的基础上,选出了厚荚相思,卷荚相思和马占相思3个有推广前景的速生树种,为我国热带亚热带地区增加了新的造林树种。  相似文献   

8.
三种相思树种的耐寒性评估   总被引:2,自引:1,他引:1       下载免费PDF全文
采用电导法对南亚热带的马占相思、大叶相思、厚荚相思的幼苗在树种和种源2个层次上的耐寒性进行了评估,并进行了排序。结果表明:在树种和种源层次上,3种相思耐寒性变异均达极显著差异;马占相思的低温敏感区为6℃,大叶相思和厚荚相思的低温敏感区为0~3℃;最耐寒的马占相思种源是17703,大叶相思种源是19244,厚荚相思种源是17562和16598。  相似文献   

9.
本文报道了在景洪、普文、思茅、河口、瑞丽5个地点所同时进行的马尖相思多点栽培试验2,5年生林分的测定结果。初步证实云南北热带及南亚热带南部,年均温18℃以上,>10℃积温6300℃以上,年降水量1200mm以上,土壤pH值4~6,无霜或偶有轻霜的地区是马尖相思的适生区。在此区域内马尖相思表现出初期速生,年平均树高生长量达1.46~1.72m,胸径生长量1.17~1.53cm。育苗造林措施与幼林管理质量对其生长影响很大。  相似文献   

10.
凤庆县是我省核桃老产区之一,核桃属温带、喜光的阳性树种,适宜生长的环境因素是:海拔1400-2500m之间,年均温在9-17℃,年降水量500-1200mm,年日照时数2000小时以上,无霜期150-240天;适宜生长在背风、向阳或半阴坡的坡基部、土层深厚的石灰质土壤上,通过对示范基地的地形、土壤、植被、气候等环境因子的分析和对现有栽培核 桃生态习性的调查,根据海拔、坡向和腐殖层厚度将核桃示范基地划分为中亚热带、北亚热带和南温带三个立地类型带,12个立地类型,并进行了产量预测。  相似文献   

11.

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.  相似文献   

12.

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.  相似文献   

13.
Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered.  相似文献   

14.

Mean age, mean and top heights and yield were studied in 20 mixed stands of birch ( Betula pubescens Ehrh. and B. pendula Roth) and Picea abies (L.) Karst. and nine mixed stands of birch and Pinus sylvestris L. in south-eastern Norway. Each mixed stand and the adjacent pure coniferous stand (control) were growing under the same site conditions and had not been commercially thinned. There were no significant differences in mean age at breast height or in top heights between birch and conifers in the mixed stands, while mean height was significantly higher for birch than for spruce. A growth index was calculated based on total volume and age at breast height. For the spruce sites the growth in young mixed stands (birch < 17 m) was superior to that of pure spruce, while the difference was insignificant in older stands. The growth index correlated positively with the ratio between generatively and vegetatively regenerated birch trees, and negatively with the age of the oldest species in the mixture and with site quality. For the pine sites there was no significant difference in the growth index between mixed birch-pine and pure pine stands. A mixture effect of birch on the volume yield of spruce or pine could not be demonstrated.  相似文献   

15.

An outbreak of the needle-shortening pine gall midge, Thecodiplosis brachyntera , occurred on Scots pine, Pinus sylvestris (L.) and lodgepole pine, P. contorta (Dougl.) in central Sweden during 1995-1998. The larval feeding of T. brachyntera kills current-year needles and heavy infestation causes severe defoliation. A pattern of fluctuating defoliation among years and sites was found on both pine species. Defoliation was evenly distributed in the crown of P. sylvestris during years of high as well as low infestation; apical whorls had as much defoliation as basal whorls. In P. contorta , however, there was a tendency for defoliation to be concentrated on branches in the most apical whorls. Growth ring increments on P. sylvestris with high levels of defoliation (71%) did not differ from trees with moderate levels (26%) of defoliation. Shoot lengths were significantly shorter, however, on heavily infested trees the year after defoliation.  相似文献   

16.

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.  相似文献   

17.

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.  相似文献   

18.

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.  相似文献   

19.
本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。  相似文献   

20.
Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week−1 for leaves and from 0.0225 to 0.0633 week−1 for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > TithoniaEuphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient enrichment capacity and slower decomposition rates which would minimize leaching losses. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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