生态学中关键种与物种重要性的概念(英文)

在本文中,对关键种的概念进行了讨论,并介绍了关键种的典型特征及其在群落和生态系统中的判别。在对关键种的研究基础上,首次提出了物种重要性(SI)概念。物种重要性可以简单地理解为生态系统中物种的重要值,它由三个指数构成,即物种结构重要值(SIV)、功能重要值(FIV)和动态重要值(DIV)。本文同时评价了三大硬阔森林生态系统中乔木树种的物种重要性。     

科学引进外来物种正确防治物种入侵

外来物种是当今生物多样性保护的一个重大话题。作者提出了外来物种主要集中在大中城市及周边农村;分析了湖南省外来物种分布现状;提出了正确认识外来物种,科学利用外来物种,建立起立法、检疫、监测等综合防治体系,不断提高防治外来物种入侵的能力和意识,逐步完善防治外来物种入侵的法律制度。     

Target species identity is more important than neighbor species identity

This study investigates how the ability to overtop other saplings and the ability to capture most of the incident light together determine interspecific competition in young and dense self-thinning stands. To this end we measured crown positions and stratification, and quantified the effect of total foliage mass and foliage mass density of neighboring trees on the relative crown depth (RCD) of target trees. Field measurements were done on naturally established saplings in two large forest gaps of different age (5- and 15-year-old) in The Netherlands, and consisting of four species differing in shade tolerance.     

濒危"表亲"知多少

16馨籍慧黯赫毓癫巍各卜万银翻啊斜一冲攀磷攀彝~}鬓薰兹鲁箭趣瀚熬玺潺谬﹃鸳「…黔毅添赢赢碱鹭夔骥澳彝瓤攫崛i蘸灌黯黔黔颧数巍篡巅鬓誉协、朴箕…镖碱蒸…鲜卿蟀熟姗咧濒橇毅_黯黔衅卿鲜擎暴誓蘸癫森舔囊摹翼翼谬巅瓣雕嘱一(袋鬓)摹攘聆黝沁蒸卿膏卿蒸颤彝锄咖巍洲争钾一拿薪褥岸鬓娜擎i夔鞭鹜壤屑俩一从彝黝毅旨i、黝鬓寿黝嶙一彝鄂豪科黔鸯扬涵奈奢岸毅量爵锄恤暴鄂鼎…、瓣磷,黔聋封娜瓣率喊向彝肇蓦{恻暴勘嘎分蠢霹一画{撇黝鲡磷)濒斌翼户{濒毅量备少俞扛袖鲍黑18濒危“表亲”知多少@郭耕     

Bondability of tropical fast-growing tree species I: Indonesian wood species

To estimate the potential bonding performance of bonded wood products from tropical fast-growing tree species, a study on the bondability of Paraserianthes falcataria L. Nielsen, Pinus merkusii Jungh et. De. Vriese, and Acacia mangium Willd from Indonesia was conducted. Two-ply laminations were produced using polyvinyl acetate emulsion (PVAc), urea formaldehyde (UF), resorcinol formaldehyde (RF), and water-based polymer isocyanate (API) adhesives. In order to determine the bonding performance, the block-shear test was applied according to the Japanese Agricultural Standard for structural glued laminated timber under normal conditions and after accelerated-aging treatments. To support this study, the wettability of each wood species was also investigated through contact-angle measurement. The results showed that the bonding performance of low-density P. falcataria was better than that of medium-density P. merkusii and medium-density A. mangium, while the bonding performance of medium-density P. merkusii was better than that of medium-density A. mangium. Furthermore, compared with A. mangium, the small contact angle and good wettability in P. falcataria and P. merkusii result in better adhesion and more intimate contact between the wood surfaces and adhesive.     

Biomass component equations for Latin American species and groups of species

? Studies dealing with the estimation of biomass, site productivity and the contribution of forests to the global carbon balance require the use of allometric equations. There have been a great number of equations developed to estimate biomass components of trees and shrubs in various ecosystems. However, there are less literature compilations that address the calculations of biomass components.

? I report a total of 229 sets of allometric equations to estimate biomass components for 102 species in 72 different forest communities of arid, semi-arid, subtropical, tropical and temperate Latin-American ecosystems.

? The selection of the appropriate allometric model is a key element in the accurate estimation of biomass, stand productivity, carbon stocks and fluxes, and as a consequence, it is important to apply special effort to the selection and estimation of biomass equations.

? I also discuss statistical methods of parameter estimation and recommend the dissection of two conventional allometric equations when biomass studies are conducted on a wide range of diameters. In order to use nondestructive procedures of biomass estimation such as the fractal theory, the null hypothesis that the mean slope b value is equal to 2.67 was rejected for Latin American biomass species.

? This information is critical for the establishment of environmental projects that aim to estimate conventional parameters (i.e., productivity, habitat quality and fuel wood) as well as environmental features (i.e., stocks and fluxes of carbon and nitrogen).

     

关于增加造林物种的多样性引进优良树种的建议

在"天然林保护工程"的启动实施中,增加新的造林树种,丰富林木优良基因也是不可忽视的问题.大兴安岭地区由于气候比较寒冷,无霜期短,可供造林树种比较单一,在一定程度上制约了林业工作的发展,为此,加快林木引种的进程,实现此地区造林树种的多样化,促进林业事业的发展,增加林产品的种类,提高森林的稳定性及抗性,充分发挥森林的防护作用和森林美化、净化价值,更好地为林区经济建设服务具有十分重要的意义.     

天然次生林生态经营思想——栽针保阔

由于天然次生林的面积不断增加,如何有效地对天然次生林的合理改造和经营是我国面临的重大问题."栽针保阔"经营思想不仅在天然林的经营方面为我国林业的可持续发展提出了理论依据,而且在利用森林自身潜力和发挥森林的生态效益方面做出了指导.     

The Armillaria species in Europe

A literature survey is given of the five European honey mushrooms Armillaria mellea, A. borealis, A. bulbosa, A. cepistipes, and A. obscura (syn. A. ostoyae) (corresponding respectively to Korhonen's intersterile groups D, A, E, B, and C); two forms of A. cepistipes are discussed: the tiny A. cepistipes f. cepistipes from Czechoslovakia and West Germany and the more common A. cepistipes f. pseudo-bulbosa Romagnesi et Marxmüller. Nomenclature, geographical distribution, hosts, some characteristics, and practical importance (including pathogenicity) are treated.     

One new species and one new record species of Acerophagus(Hymenoptera: Encyrtidae) from China with a key to Chinese species

Two species of Acerophagus from Yunnan Province, China, are reported. One species, A. ovaliclavus sp. nov., is described as new to science, and one species, A.solidus Hayat is reported as new to China. A key to all described species from China based on females is given.All the type materials are deposited in the insect collections of Northeast Forestry University, China.     

Chemical components of Fraxinus species

A wide range of chemical components including coumarins, secoiridoids, phenylethanoids, flavonoids, and lignans has been isolated from Fraxinus species. Extracts and metabolites have been found to possess antiinflammatory, immunomodulatory, antimicrobial, antioxidative, skin regenerating, photodynamic damage prevention, liverprotecting, diuretic and antiallergic activities. Some species find application in contemporary medicine. In the present review the literature data on the phytochemical and biological investigations on the genus Fraxinus are summarized up to the middle of 2004.     

锦鸡儿属树种杂交试验初报

在连续几年对锦鸡儿属不同品种的种内、种间杂交试验的基础上,通过对杂交方法、花粉收集、保存、杂交种子的品质等的初步探索,为今后更好地提高杂交技术及选育新品种,提供了基础资料。     

A NEW SPECIES OF VALSA

The papr has reported a new species of Valsa came from the twigs andbranches of Cryptomeria fortunei Hooibrenk ex Otto et Dietr.It was named as Valsa forunea Zhao,Sheng et N.Li sp.nov.when it is in the perfect stage and Cytospora fortunea Zhao,Sheng et N.Lisp.nov.in the imperfect stage.The new species has been described both in Latin and in Chinese,aswell as the differences between the new species and other similarities.The type specimen of the newspecies is deposited in the plant pathology Herbarium of Southwest Forestry College,Kunming(HSFC 15206 Type).     

Cytotoxic activities of Stachys species

The cytotoxic activity of Stachys plants and of aucubin and harpagide against MCF7-breast adenocarcinoma, HeLa-cervix adenocarcinoma, A431-skin carcinoma of epithelial origin is reported in this study. Cisplatin and doxorubicin were use as reference compound.     

槭属植物远缘杂交初探

以美国红枫为母本,我国原产的元宝枫为父本,采用直接授粉法、切除柱头法、切除柱头加化学试剂法3种方法在温室条件下,用超低温保存的元宝枫花粉对带有花芽的离体美国红枫枝条进行授粉实验;子房发育约20~25d之后,分别采集经不同处理的子房对其进行表面灭菌处理后,接种于1/2MS+6-BA(0.01mg/L)+NAA(0.1mg/L)的培养基上进行胚抢救培养。结果表明:含水量为12.2%的花粉经超低温保存一年之后,保持着与新鲜花粉相当的活力。3种不同的授粉方法中,生长情况最好的为直接授粉法,切除柱头加化学试剂法次之,而切除柱头发效果最差。通过胚抢救技术获得了一定量的杂种后代株系。     

Physiological regulation of poplar species to experimental warming differs between species with contrasting elevation ranges

Climate warming has resulted in rapid range shifts of plant species, but it is not well known how species with different natural distribution ranges adapt to increase in temperature through physiological adjustment. We experimentally imposed a 1.8 °C increase of air temperature to the cuttings of two common poplar species Populus yunnanensis and Populus szechuanica naturally growing in southwest China using open-top chambers. Populus yunnanensis is distributed along a narrower elevation range compared with P. szechuanica. We determined some key physiological parameters and plant growth regulator activities during the growing season without soil water limitation. Our results showed that a 1.8 °C increase in air temperature increased shoot growth of P. szechuanica through an extension of its growth period but did not affect the growth of P. yunnanensis. Malondialdehyde content, guaiacol peroxidase activities and abscisic acid content increased while indoleacetic acid content decreased in P. yunnanensis. Our results suggest that the two common poplar species in southwest China should be able to adapt to the moderate increase in temperature projected for future climate. The growth of P. szechuanica may benefit through phenological adjustment but a further increase in temperature may inhibit the growth of P. yunnanensis. For poplar plantation management, selecting species with a wide natural distribution range could provide an adaptive alternative for buffering anthropogenic induced increase in temperature and help in sustaining productivity for the long term.     

加强引种审批和监管防止外来有害生物入侵

5月30日,国家林业局颁发了《引进林木种子苗木及其它繁殖材料检疫审批和监管规定》,这项规定是在什么背景下颁发的?它将起到哪些作用?请看国家林业局主管部门有关人士撰写的诠释文章。     

Structure and species composition of novel forests dominated by an introduced species in northcentral Puerto Rico

The African tulip tree, Spathodea campanulata Beauv., is an introduced species forming novel forest types in Puerto Rico. These forests develop naturally after deforestation, agricultural use and land abandonment, and there are many questions as to their ecological characteristics. We sampled structure and species composition of large, small, and juvenile trees (≥10, ≥2.5 to <10, and <2.5 cm diameter at breast height, respectively) in nine secondary forests dominated by S. campanulata on alluvial, karst, and volcanic substrates in northcentral Puerto Rico. No differences were found in S. campanulata forest structure between substrates. Of a total of 79 species found, 17 were introduced. Forests on karst and alluvium had the highest and lowest global species richness, respectively. Species richness increased from large to small to juvenile trees in most sites, but more so on karst. The percentage of introduced species was inversely related to species richness of tree size classes on all substrate types. The dominance of S. campanulata in the large tree size class was highest and lowest in alluvial and volcanic sites, respectively, and decreased from large to small to juvenile trees on all substrate types. Species richness of S. campanulata forests is lower than that of native forests on equivalent substrates. Although land use history affects composition, the juvenile tree species established in S. campanulata forests seems to correspond to the geological substrate were sites are found. This study shows S. campanulata restores forest structure and native tree species on abandoned agriculture and grazing lands in Puerto Rico. Management of these novel forests should consider them as resources were natural processes have the potential of making them more diverse.