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1.
Ph.rubromarinataMcCI.inLingn.Uni.Sci.Bull.9:44,1940.H.Fung20545(TypeinUSA,notseen);H.Fung20894(Paratype,SYS)Ph.auritaJ.L.LuinJourn.HonanAgr.Coll.2:71,fig.1(1981);AComp.Chi-neseBamb.:112,1994;TheBamboosoftheWorld,GenusPhylostachys,3rded:23,1996;Fl.ReipPop.Sin.9(1):301,P1.83(1-4),1996.Henan(河南),Zhengzhou(郑州),J.L.Lu(卢炯林)78101号(Type,HEAC)采自河南农学院竹类标本园,载植号(14),系1972年由广西柳州引入,勿n.no…  相似文献   

2.
Introduction The life history of many bamboo species is characterized by an unusual flowering habit. They often flower and die simultaneously over wide areas at long intervals (3–120 years), and then regenerate from seed or rhizome (Janzen 1976; Liese 19…  相似文献   

3.
Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China (the original of the natural Mongolian pine, forest on sandy land) was studied in 2004. The total mean values of regeneration indexes were higher in mature stands (more than 80% individual stems were older than 50 years), the maximum of regeneration index reached 29 seedlings, m^ 2, with lowest values in the younger stand, e.g., in 32-year old and 43-year old stands. The stand age was an important factor determining the natural regeneration, which was the best in the older stands in this investigation (e.g. about 80-year old). The regeneration index seemed not to be closely in relation to canopy openness although Mongolian pine is a photophilic tree species. In each type of gaps, natural regeneration was very well. Regeneration indexes were satisfactory at the south and east edges in the circle gaps; and at the east edge of the narrow-square gaps. Results indicated that Mongolian pine, seedlings could endure shading understory, but it would not enter the canopy layer without gap or large disturbance, e.g., fire, wind/snow damage or clear cutting etc. These results may provide potentially references to the management and afforestation of Mongolian pine, plantations on sandy land in arid and semi-arid areas. Researches such as the comprehensive comparisons on regeneration, structure and ecological conditions and so on between natural Mongolian pine, forests and plantations should be conducted in the future.  相似文献   

4.
Biosphere reserves have been brought into Man and Biosphere (MAB) Programme, which are recognized by the world. Biospherereserves are the representative continent and ocean protected (The Chinese National Committee for MAB 2000). As an important type of the international protected area named by the United Nations Educational, Scientific and Cultural Organization (UNESCO), biosphere reserves have played an important role in protecting global biodiversity, promoting the sustainable uti…  相似文献   

5.
This paper reports two newly recorded species, lsohypsibius lunulatus Iharos, 1966 and lsohypsibiusprosostomus Thulin, 1928, of the genus lsohypsibius (Tardigrada; Hypsibiidae) from China. The specimens of lsohysibius lunulatus were collected from Taibai Mt (34°18′N, 107°42′E) at 2,500 m a.s.1, and those oflsohypsibius prosostomus from Taibai Mt (34°10′N, 107°35′E) at 2,000 m above sea level. All specimens are deposited at the College of Life Sciences, Shaanxi Normal University, China. A key to the Chinese species of lsohypsibius was also given.  相似文献   

6.
We studied variations in tree biomass and carbon sequestration rates of Chir Pine(Pinus roxburghii. Sarg.) forest in three categories of forest disturbance, protected, moderately disturbed, and highly disturbed. In the first year, total biomass was 14.7 t?ha-1 in highly disturbed site, 94.46 t?ha-1 in moderately disturbed forest, and 112.0 t?ha-1 in protected forest. The soil organic carbon in the top 20 cm of soil ranged from 0.63 to 1.2%. The total rate of carbon sequestration was 0.60(t/ha)·a-1on the highly disturbed site, 1.03(t/ha)·a-1 on the moderately disturbed site, and 4.3(t/ha)·a-1 on the protected site.  相似文献   

7.
《林业研究》2020,31(2)
To characterize the effects of plantation densities on the growth characteristics(diameter at breast level,tree height and volume) and the common wood properties,38-year-old Populus simonii 9 P.nigra clones planted with four levels of spacing(2 m × 2 m,3 m × 3 m,4 m × 4 m,and 5 m × 5 m) in a semi-arid area in northeastern China were examined.The results of ANOVA showed significant differences(P0.01) for all the investigated growth traits and wood properties under different plantation densities,except for the chemical composition of wood.The repeatability and phenotypic variations of all the traits varied from 0.34 to 0.99 and from 13.45 to 59.65%,respectively.Except for wood density,which was significantly negatively correlated with the growth traits,a positive correlation was observed between the growth traits and all the other wood mechanical properties.However,most of the correlations between the growth traits and the chemical composition of the wood were not significant.The path analysis for the wood mechanical characteristics and the growth in the prediction of volume were significant and ranged from 0.18 to 0.72 for wood density and diameter at breast height,respectively,while those for the chemical composition of wood ranged from 0.001 to 0.336,which showed a low impact on the volume.The highest stand volume(610 m~3) per hectare was observed with the 2 m × 2 m spacing,which consequently provided a high total price and income,while a high individual volume growth per tree was observed with the 5 m × 5 m spacing.The results suggested that for the poplar trees younger than 40 years in a semi-arid area in China,2 m × 2 m spacing is suitable for obtaining a high volume per hectare,while 5 m × 5 m spacing is best for obtaining a high individual volume per tree.  相似文献   

8.
In order to examine the causes of degradation of Pinus sylvestris var. mongolica plantations on sandy land, the foliar concentrations of N, P, K and C were analyzed and compared between the field grown P. sylvestris var. mongolica trees from two provenances (natural forests and plantations). The results indicated that natural tree needles had lower N, P and C concentrations, and higher K concentrations than those of plantation tree needles. For plantation tree needles, ratios of N: P, P. K and N: K increased with tree age before 45 years old; but they were not clear for the natural tree needles. Compared with the conclusions reported on Pinus spp., we found that the foliar N and P concentrations were in the optimal range for both natural and plantation tree needles. This result suggested that N or P might not be the absolute limit factors in plant nutrient for P sylvestris var. mongolica on sandy land. However, foliar K concentrations in both natural and plantation tree needles were much lower than those reported on Pinus spp. (〉4.80 g kg-1).The N: P ratio of natural needles was in the adequate ranges, but N: P ratio of plantation needles was out of the adequate ranges. These results indicated that there was a better balanced nutrition status in the natural forest than in the plantations. If only considering the foliar nutrient concentrations of P sylvestris var. mongolica from different provenances, it might be concluded that the degradation phenomenon of P. sylvestris var. mongolica plantations was not induced by nutrition deficiency of absolute nutrients of N and P, but might be induced by other mineral nutrients or by the effectiveness of N and P nutrients. The unbalanced nutrition status and relatively quick decomposition of needles in the plantations might also contribute to the degradation.  相似文献   

9.
Guizhou golden monkey (Phinopithecus roxellanae brelichi) is a peculiar, rare and endangered species. It is distributed most narrowly and requires a rigorous habitat. In this study the habitats of Guizhou Golden Monkey were divided into three habitats: most suitable habitats, suitable habitats and marginally suitable habitats. The characteristics of the vegetation community, environmental factors and extreme environmental factors in the three habitats were systematically analyzed. The seasonal activity rule, activity area and the food characteristic of Guizhou golden monkey were also study at the same time. The results indicate that the evergreen and deciduous broadleaf mixed forest is the optimal living vegetation community for Guizhoug olden Monkey, and the suitable annual temperature is 8-15℃, the extremely lowest temperature is -2.5℃, the extremely highest temperature is 25℃, and the optimal living altitude is 1500-1700 m. In the same area, the higher the vegetation diversitythe more suitable it is for the life of Guizhou golden monkey. Temperature and food are the main habitat factors in determining the activity scope of the guizhou golden monkey community. The Altitude, temperature and the characteristics of the vegetation community are the main limitina factors for habitat selection.  相似文献   

10.
All of the plants can be combusted. The mechanism of forest belts resistance is that the tree species weren‘t liable to be burned compared with other plant species. In this paper new concepts on fire resistant trees and fuel-breaks trees were presented. The fire resistance mechanism includes 3 aspects, fire-resistant tree species, rational construction forest belts and environment. Tree crowns can resist fire forwarding. Forest belts can form the environment, which is not easy to fire, and also make fuels distributed discontinuous. The network of forest belts has large area of conifer forest segregated. The ideal f‘ire resistant tree species had better to embrace some characteristics, such as high f‘ire resistance, rational planting and biological characteristics.  相似文献   

11.
研究了华中神农架自然保护区毛金竹(Phyllostachys nigra var. henonis (Mitford) Stapf. ex Rendle) 从发笋到成竹的营养生长行为。竹笋在5 月份出土,在16 天的发笋期内平均密度达到2.7 笋/m2。大约32% 的新笋死亡。昆虫损害、萎焉死亡、鼠类摄食分别占竹笋死亡总量的57%,29%和14%。5–6 月份,竹笋在34 天的升高期内长到400 ±23 cm 的高度,日增高1–56 cm。7–8 月份为发枝期,在此期间枝叶展开、竹竿发育定形。竹笋产量与立地成竹的密度正相关,而与立地草本层的高度负相关。图4 表3 参46。  相似文献   

12.
毛金竹叶提取物抗衰老作用的实验研究   总被引:18,自引:0,他引:18  
用昆明种小鼠作为试验对象,研究了毛金竹叶提取物(LE)抗衰老的生物学效应。结果表明:高剂量组的LE能显著增强小鼠对非特异性刺激的抵抗能力(常压耐缺氧试验,p<0.01)和抗疲劳能力(游泳试验,P<0.01);对正常小鼠的学习能力有一定的促进作用(电迷路法,p<(0.05);对老年小鼠体内的超氧化物歧化酶(SOD)和谷胱苷肽过氧化物酶(GSH-Px)活性有显著的诱导作用;并且明显抑制了老年小鼠血浆过氧化脂质(LPO)的生成、降低了肝脏脂褐素(LF)的含量等。研究结果提示LE具有一定的抗衰老作用,竹叶可以作为一种抗衰老功能因子的新资源加以研究和开发。  相似文献   

13.
茶秆竹新竹生长规律的研究   总被引:3,自引:0,他引:3  
通过对茶秆竹的鞭芽及幼竹--成竹生长规律的观测,结果表明:茶秆竹的鞭芽于8月上旬开始分化,鞭芽数随着鞭龄的增大而降低。当年的鞭可以分化成鞭芽和笋芽,茶秆竹立竹主要集中在壮龄和中龄鞭上,立竹的着生部位以鞭的中、后段为主。竹笋出土可分为3个时期,高生长可分为4个阶段,高生长节律呈S形,符合Logistic曲线。  相似文献   

14.
[目的 ]探讨煤污病对灰金竹生长的影响,为灰金竹的科学栽培管理提供参考。[方法 ]分别以正常和染病的灰金竹为研究对象,采用Li-6400XT便携式光合系统测量叶片的光合特性指标、实验室测定生理特征指标、立竹构件与生物量等指标,从生理代谢角度评价煤污病害对灰金竹的影响。[结果 ](1)煤污病可显著影响灰金竹的光合作用,煤污病导致灰金竹光合速率、气孔导度和蒸腾速率等降低,却增加了胞间CO2浓度和叶绿素含量。光照强度是影响正常灰金竹光合速率的主导因子,胞间CO2浓度和大气CO2浓度是影响染病灰金竹光合速率的主导因子。(2)灰金竹感染煤污病后,可溶性蛋白含量降低,超氧化物歧化酶活性和丙二醛含量升高,叶片衰退速度加快,将光能转化为化学能的机能下降。(3)正常灰金竹立竹指标值均比染病灰金竹的立竹指标高,除地径和枝下高差异不显著外,胸径、全株高和厚壁率差异显著(P <0.05),且正常灰金竹生物量显著大于染病灰金竹。[结论 ]煤污病影响灰金竹的光合特性,使其光合作用降低,叶片生理指标发生变化,叶片衰退速度加快,进而影响立竹指标和...  相似文献   

15.
辽东山区20世纪80年代开始从内蒙古红花尔基引种樟子松营造人工林。20多年的实践表明,樟子松人工林在15 a生前生长较快;直径、树高连年生长量15 a生后呈下降趋势,20 a生后下降显著;直径、树高平均生长量20 a生后下降明显;15 a生前针叶量正常,而15 a生后针叶量明显下降,生长势弱,保存率低,纬度愈低生长愈差;生长量明显低于同龄的日本落叶松、红松,亦低于冷杉和云杉。因此,樟子松在辽东山区只适宜在较差立地上营造生态公益林,不宜作为培育用材林的树种。  相似文献   

16.
根据标准地和解析木调查资料,以樟子松人工林树冠内活枝为研究对象,探讨同一树木的不同龄阶的枝生长规律,同一林分不同大小树木枝生长的规律,以及不同林分条件下枝生长的规律。结果表明:单株树木枝条长度总生长曲线呈"S"形,连年生长在生长初期达到一最大值后随年龄的增加而逐渐减小;在同一林分中,枝条总生长随着枝龄的增加而持续增长;在不同年龄相同密度林分中,年龄较小的林分枝长连年生长要比年龄较大的树林增长快一些;在相同年龄不同密度林分中,密度较小的林分比密度较大的林分枝长总生长及同期连年生长要快一些。  相似文献   

17.
华中神农架山地竹类及其分布   总被引:3,自引:0,他引:3  
Inventory recorded 4 genera and 11 spacies of mountain bamboss in Shennongjia,Central China.Of these,4 species (Phyllostachys nigra var.henonis,Ph,heteroclada,Ph.nidularia and Ph.Bambuskoides) beiong to the monopodial bamboo,4 species(lndocalamus latifolius,I.longiauritus,l.wilsoni and l.tessellatus)to the amphipodial barnboo,and 3 species(Fargesia spathaces,F.munelae and Yushania contusa)to the sympodial bamboo.Monopoodial bamboos grow on the gentle slopes below 1800m asl,occurring from the subtropical belt to the temperate belt in the vertical climatic spectrum of the mountain;Sympodial bamboos occur in higher elevations,ranging from the warm temperate(1200m),across the mediate temperate and cold temperate,to the mountaintops of the frigid temperate belt(3100m).Amphipodial bamboos occur in all climate types except the frigid temperate belt.three dominant species,F.spathacea,F.murielae and Y.confusa,currently cover 12%,9% and 3% of the mountain ranges in Shannongjia,respectively.  相似文献   

18.
在中国534个竹子种类中,遴选了153种笋用竹。其中刚竹属、箭竹属、牡竹属、寒竹属、香竹属和绿竹属占据笋用竹种类的78%。在笋用竹中,56种具有商业价值,其中的16种具有世界市场。通过对所有笋用竹的商业价值、形态特征、生态特征和种植特点的种植潜力指数评价,将笋用竹分为5个类别:第一类(9种)具有很高的商业价值,大面积种植前景,第二类(33种)可以区域性种植。  相似文献   

19.
我国西南地区竹亚科(禾本科)属种新记录   总被引:1,自引:0,他引:1  
本文报道我国西南地区竹亚科新记录种3种及1栽培品种,其中美浓麻竹Dendrocalamus latiflorus Munrocv.Mei-nungW.C.Lin为云南、贵州新分布,也为中国大陆新分布;廉序repanostachyum及多毛廉康竹D.hirsutiss mumW.D.LietY.C.Zhong为广西新分布;青秆竹Bambusa tuldoides Munro为广西、贵州新分布;桂单竹B.guangxiensisChia etH.L.Fung为贵州新分布。  相似文献   

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