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1.
山茶、金花茶、油茶、广宁油茶   总被引:1,自引:0,他引:1  
陈定如 《广东园林》2008,30(1):77-78
常绿灌木或小乔木,高2~10m。树冠卵球形或近球形。树皮光滑,嫩枝无毛。叶互生,革质,椭圆形、卵形或倒卵状长圆形,长5~10cm,宽2.5~5.5cm。基部阔楔形或圆,先端短头或尾状渐尖,上面深绿色,下面浅绿,两面有光泽,边缘有锯齿。花通常生于枝顶部或腋生,1~3朵;花冠直径5~10cm。花瓣6~7片,红色,有粉红色、白色或杂有色斑及单瓣和重瓣的栽培变种;雄蕊多数,花药黄色。蒴果球形,直径2~3cm,具宿存花萼,通常不正常发育结果。花期1~4月;果8~10月成熟。  相似文献   

2.
苏铁、木麻黄、夹竹桃、黄花夹竹桃   总被引:1,自引:0,他引:1  
陈定如 《广东园林》2010,32(4):79-80
<正>苏铁(铁树、凤尾蕉)Cycas revoluta Thunb.苏铁科棕榈状常绿灌木或小乔木,高1~6 m。茎干单生或有分枝和丛生,粗壮,有叶柄残体和痕迹。树冠伞状。叶呈螺旋状于茎顶聚生,一回羽状,长0.5~1.5 m,宽15~35 cm;羽片多数,呈V形斜展,质地坚硬,条形,长5~20 cm,上面深绿色有光泽,先端刺尖,边缘向下反卷;叶柄两侧有齿状刺。雌雄异株,孢子叶球(球花)于茎顶部单生;小孢子叶球(雄球花)圆柱状宝塔形,直立,长30~70 cm,直径10~15 cm,小孢子叶长方状楔形,黄色;大孢子叶球(雌球花)球形或扁球形,直径20~30 cm,大孢子叶上部卵状扇形,边缘呈羽状  相似文献   

3.
陈定如 《广东园林》2009,31(3):76-77
土沉香(自木香、女儿香、莞香、香树) 常绿乔木,高达20m。树皮暗灰色,平滑,韧皮纤维发达,易剥离;木质部白色,小枝被柔毛。树冠广9日形或伞形。叶互生,坚纸质,椭圆形或长圆形,长5~10cm,先端短渐尖,基部宽楔形,上面亮绿平滑,背面中脉凸起,侧脉细而平,近平行斜出。伞形花序顶生或腋生,花淡黄色,芳香。  相似文献   

4.
陈定如 《广东园林》2009,31(6):78-79
常绿乔木,高可达40m。树皮粗糙,呈不规则块状深裂,较厚,有树脂。树冠宽塔形或伞形。叶通常2针1束,稀3针;针叶较细柔,长8~20cm,直径0.9mm,具纵浅槽沟,边缘有微刺齿;叶鞘长6~9mm。球花单性。雌雄同株;雄球花生于新枝下部的苞腋,短圆柱状。黄色;雌球花生于新枝近顶端。卵形,淡紫色。  相似文献   

5.
本法是在样品中加入适量的缓冲剂,使难发挥元素Be形成易挥发的氟化物,与B、Pb、Mo、Sn、Cu、Ag、Zn等元素在同一时间内蒸发,利用深电孔极的分馏效应,有效地降低光谱背景以及被测元素的检出限。加入内标元素,提高了方法的准确度和精密度。采用深孔电极,取样量大,代表性好。一次摄谱,同时检测多个元素,大大提高了工作效率,又减少了测试费用。方法操作简便,适合于大批量样品的测试。检出限ω(B)/10-6分别达到:Be:0.50、B:0.91、Sn:0.50、Ag:0.02等,均满足《覆盖区多目标地球化学调查样品测试及质量监控暂行规定》规定。  相似文献   

6.
《云南林业》2012,(2):51-54
云南省林业产业协会第二届会员代表大会于2012年3月13日在昆明召开,会议选举产生了协会第二届名誉会长、名誉副会长、会长、副会长、秘书长、常务理事、理事。名单如下:  相似文献   

7.
陈定如 《广东园林》2010,32(5):78-79
<正>木芙蓉(醉酒芙蓉、拒霜花、芙蓉花)锦葵科Hibiscus mutabilis L.落叶灌木或小乔木,高2~7 m。树皮灰色,韧皮纤维发达,枝条披散,密被星状毛及柔毛。树冠近球形。叶互生,纸质,卵圆状心形,长10~15 cm,  相似文献   

8.
9.
陈定如 《广东园林》2010,32(3):79-80
<正>麻楝楝科Chukrasia tabularia A.Juss.常绿或半落叶乔木,高10~30m。树干通直,树皮褐色,纵裂,略粗糙,具棕色皮孔,内皮层棕红色。嫩枝及芽被锈色短绒毛。  相似文献   

10.
降香黄檀、鸡冠刺桐、刺桐、白花油麻藤   总被引:2,自引:0,他引:2  
陈定如  王缺 《广东园林》2009,31(2):76-77
落叶或半落叶乔木,高10m~20m。树干略弯斜,分枝低;树皮幼时灰色,平滑。壮龄后褐色,粗糙,纵裂;小枝柔软,具凸起小皮孔。树冠广伞形。叶互生,一回奇数羽状复叶,有互生小叶7~13片,总叶柄基部膨大;小叶纸质或近革质,卵形、卵状椭圆形至长椭圆形,先端钝或渐尖,  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.

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   

14.

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   

15.
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   

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.
18.

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.  相似文献   

19.
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.  相似文献   

20.
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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