贵州槭属二新种

<正> Acer guizhouense Y. K. Li, sp. nov. (Sect. Integrifolia Pax, Set. Penninervia Metc.) Species affinis A. oligocarpo Fang et L. C. Hu, differt foliis base cuneatis, venulis reticulatis in sicco utrinsecus manifeste elevatis; infruetescentiis paniculatis; etiam a A. foveolato C. Y. Wu, petiolis brevibus 6—8mm longis,     

色木槭天然次生林群落结构特征

对色木槭天然次生林群落进行研究,测定了该群落主要乔木树种的重要值,分析了该群落的种类组成,物种多样性。结果表明：色木槭天然次生林乔木层共有16个种群,其中色木槭、蒙古栎、糠椴、山榆占明显优势,为该层的优势种和建群种;径级以<15 cm的株数最多,占总株数的87.82%,林分幼树更新数量充足。群落的Simpson指数为0.833、Shannon-wiener多样性指数为2.101、丰富度指数为2.291、均匀性指数为0.758和生态优势度指数为0.113。乔木层立木以低龄种群在群落中占优势,为了促进群落将向地带性典型植被类型演替,提出了抚育管理的建议。     

Using management to address vegetation stress related to land‐use and climate change

While disturbances such as fire, cutting, and grazing can be an important part of the conservation of natural lands, some adjustments to management designed to mimic natural disturbance may be necessary with ongoing and projected climate change. Stressed vegetation that is incapable of regeneration will be difficult to maintain if adults are experiencing mortality, and/or if their early life‐history stages depend on disturbance. A variety of active management strategies employing disturbance are suggested, including resisting, accommodating, or directing vegetation change by manipulating management intensity and frequency. Particularly if land‐use change is the main cause of vegetation stress, amelioration of these problems using management may help vegetation resist change (e.g. strategic timing of water release if a water control structure is available). Managers could direct succession by using management to push vegetation toward a new state. Despite the historical effects of management, some vegetation change will not be controllable as climates shift, and managers may have to accept some of these changes. Nevertheless, proactive measures may help managers achieve important conservation goals in the future.     

PERMANENT GENETIC RESOURCES: Development of polymorphic microsatellite markers in Acer mono Maxim

Thirteen polymorphic microsatellite markers were developed for Acer mono Maxim., one of the major components of deciduous forests in Japan. An average of 13.8 alleles were found, with expected heterozygosity ranging from 0.140 to 0.945 in 34 A. mono individuals from the Ogawa Forest Reserve in Ibaraki Prefecture, Japan. This set of microsatellite markers can be used to analyse mating patterns and gene flow in A. mono populations.     

色木槭天然次生林种群竞争关系研究

运用Hegyi单木竞争指数定量分析了色木槭（Acer mono）种内和种间竞争强度。结果表明,色木槭的种内竞争强度较大,占总竞争的26.1%,在早期阶段,色木槭的种内竞争强度随着径级的增加而增大,胸径大于30 cm后,其竞争强度又逐渐降低;色木槭的种间竞争强度（89.061）大于种内（31.487）,色木槭种内和种间竞争强度的顺序为：色木槭>糠椴>蒙古栎>黄菠萝>胡桃楸>紫椴;随着色木槭胸径的增大,所受到的竞争压力逐渐减小,胸径在15 cm以前所受到的竞争压力最大,竞争强度与对象木的胸径大小之间的关系近似服从指数函数关系。在自然条件下,当色木槭胸径达到15 cm前时,应对其进行抚育管理以提高木材利用率。     

辽东山区天然次生林的数量分类

结合DCA排序和TW IN SPAN分类结果,将辽东山区天然次生林划分为5个群落类型:花曲柳林、蒙古栎林、阔叶混交林、水曲柳林、胡桃楸林。DCA排序与TW IN SPAN分类产生了较一致的分类结果。DCA第一轴代表的环境意义为坡向。花曲柳林多分布于阳坡的中坡及中上坡,蒙古栎林多分布在中上坡。花曲柳与蒙古栎常混生在一起,随着坡位上升,花曲柳优势度下降,而蒙古栎优势度增加。阔叶混交林多位于阴坡,乔木层没有稳定和绝对优势种,多以假色槭、风桦、色木槭为优势种,但假色槭分布于乔木层第2亚层。水曲柳林多分布在中下坡。胡桃楸分布在山下部,喜潮湿生境。色木槭在辽东山区分布广泛,重要值较高,且更新良好,很可能是群落演替顶级物种。辽东山区天然次生林林下藤本植株数量多,以五味子、软枣猕猴桃、狗枣猕猴桃为主。     

Micropropagation of juvenile sycamore maple via adventitious shoot formation by use of thidiazuron

Zygotic embryos of sycamore maple (Acer pseudoplatanus) were dissected into plumule, hypocotyl and radicle sections. The segments were placed on MS medium containing 1 μM 6-benzyladenine (BA) and/or 0.02 μM to 0.1 μM thidiazuron (TDZ). Hypocotyl and plumule explants produced callus, adventitious buds and shoots with increasing plant growth regulator concentrations. Hypocotyls produced more, but smaller shoots compared to plumule segments. Subculturing excised shoots and calluses on Murashige and Skoog (MS) media with 1 μM BA and/or 0.04 μM TDZ led to continuous production of shoots. The best proliferation capacity occurred with 0.04 μM TDZ and 1.0 μM BA, both shoots and calluses. This combination showed a stimulatory effect also on length of newly formed shoots. Calluses performed generally better compared to shoot explants independent of growth regulator treatment. Excised shoots 2 to 3-cm-long were successfully rooted on MS media either with or without growth regulators (123 μM IBA pulse) followed by transfer to the greenhouse. This revised version was published online in June 2006 with corrections to the Cover Date.     

中国槭树科二新记录种

三裂枫Acer calcratum Gagnep．和长裂枫Acer acuminatum Wall．exD．Don两种分布于东南亚和喜马拉雅地区的珍稀树种,最近分别发现在我国云南和西藏有分布,属于我国新记录种。三裂枫属于广义鸡爪槭组sect．Palmata中华槭系ser．Sinensia,主要形态特点为叶片三裂,叶片基部圆形,伞房花序,通常只有一个发育完全的果实,坚果近卵球形。长裂枫属于尖齿槭组sect．Arguta,主要特点为叶片3裂和5裂,侧裂片和中央裂片近等长,裂片先端长渐尖,花序长达12-20cm。     

贵州槭属一新种

<正> 落叶乔木,高6米,树杆直径20厘米;当年生被鲜时红色,干时暗褐色,无毛,一年生枝灰绿色,干时也为暗褐色;芽细小,有2个对生芽鳞,叶纸质,对生,长圆形、卵状长圆形,或倒卵状椭圆形,稀椭圆形,长6.2—8.5厘米,宽2.4—4.7厘米,先端尾状渐尖,有长9—18毫米尖头,基部浅心形或圆形,边有钝圆齿,中脉与侧脉两面突起,红色,侧脉每边     

Sugar maple (Acer saccharum Marsh.) establishment in boreal forest: results of a transplantation experiment

Aim To evaluate whether seedlings of sugar maple (Acer saccharum Marsh.) can establish beyond the species northern range limit in adjacent boreal forest. Location The hardwood–boreal forest transition zone on the north‐east shore of Lake Superior, Ontario, Canada. Methods Seed fall of sugar maple was monitored for 5 years in a stand of this species at its northern range limit, and seed from this stand was transplanted to five micro‐habitat types in an adjacent boreal forest. The establishment and survival of sugar maple seedlings there, and in the seed‐source stand, was monitored for the following 7–11 years. Soil‐surface light levels were measured in both forest types. Results Most seed fell in the final year of monitoring, when c. 250 seeds m^?2 were recorded. First‐year seedling establishment rates in the maple stand, deriving from this mast seed year, was approximately double that deriving from seed transplanted to the boreal forest sites; this is tentatively attributed to seed predator satiation in the maple stand. However, subsequent seedling survivorship in the boreal forest was greater than that in the maple stand, resulting in comparable seedling densities by the end of 6 years. This difference is tentatively attributed to better illumination in the boreal forest sites, and canopy‐opening disturbances appear to be especially facilitative of seedling survival. Main conclusions There is no fundamental impediment to sugar maple seedlings establishing in boreal forest communities if climate warming occurs and seed is available. If management intervention is needed to accelerate seed availability in a rapidly warming boreal forest, then diffuse seed application to disturbed boreal forest sites during mast years of local boreal tree species is recommended as the most effective way of avoiding seed predation and increasing seedling survival.     

Analysis of morphological variation of the Acer tschonoskii complex in eastern Asia: implications of inflorescence size and number of flowers within sect. Macrantha

Flower and fruit specimens of 184 individuals were sampled to investigate patterns of intraspecific variation and to evaluate recognition of taxa within the Acer tschonoskii complex using morphometric analysis. Previous taxonomic treatments have considered A. tschonoskii var. rubripes (=  A. komarovii ) and A. tschonoskii var. tschonoskii to be separate species. The morphological discontinuity between these two taxa was evident in peduncle and pedicel length, and in number of flowers. In addition, the delimitations of some species within sect. Macrantha were clarified using these diagnostic characters. In view of the geographical distribution of the A. tschonoskii complex, which includes many taxa of sect. Macrantha from China to Japan through Korea, the long raceme with many flowers ( A. sikkimense ) and unlobed leaf are considered more primitive than the short raceme with a small number of flowers and five-lobed leaf ( A. maximowiczii and A. komarovii ). However, many intermediate taxa were present. This study also suggests that several Chinese taxa, such as A. metcalfii, A. taronense, A. hookeri and A. grosseri , may be subject to different taxonomic interpretation and should be reinvestigated morphologically.  © 2003 The Linnean Society of London. Botanical Journal of the Linnean Society, 2003, 143 , 29−42.     

元宝枫生长旺季树干液流动态及影响因素

利用热扩散式边材液流探针和多种气象、土壤因子传感器组成的全自动数据采集系统和美国产Licor-6400光合测定系统,于夏秋季节对北京西山地区低山成林元宝枫单株边材液流动态和叶片蒸腾作用进行了系统观测。元宝枫树干边材液流变化受天气的影响,环境胁迫或环境的改善都能改变边材液流的波动特征。在正常情况下,边材液流的日变化呈单峰曲线:日出后树干液流迅速上升,峰值在中午前后出现,然后下降,在次日早晨前达到坡谷。最热月7月液流启动和进入坡谷的时间比其他各月早1~4 h。6月树干上位液流速率大于中位和下位,其他各月树干下位液流速率大于上位和中位,这种差距在7月达2~3倍。多元回归分析表明,在整个生长旺季,元宝枫边材液流变化深受气温、太阳辐射、空气相对湿度、土壤温度和风速等环境因子的影响,但在不同的观测时段和观测部位其影响的主导因子不完全相同,只有空气温度在任何情况下都是影响液流的主导因子;元宝枫边材液流的变异规律较好地说明了其耐旱的生态策略。     

Effect of an artificially induced drought on leaf peroxidase activity, mineral nutrition and growth of sugar maple

The effect of an artificially induced drought was investigated in an 80-year-old sugar maple (Acer saccharum Marsh.) stand in southern Quebec. We hypothesized that leaf peroxidase activity would increase, and that leaf nutrient deficiencies typical of declining trees (K, Mg) would develop during the year following the imposition of the drought. An impermeable tarpaulin was placed on the ground at the base of the trees during the summer of 1991. Foliage and soils were sampled periodically during the summers of 1991 and 1992. The treated trees showed decreased leaf water potential and increased peroxidase activity over most of the 1991 growing season. Diameter growth was significantly reduced in 1992. Soil NO ₃ ^- and K⁺ were elevated while Mn²⁺ was reduced under the tarpaulin treatment at various times during the 1991 growing season. Soil NO ₃ ^- , NH ₄ ⁺ , K⁺ and Mg²⁺ were elevated in the treated plots at various times during the 1992 growing season even though there was a lack of effect on foliar nutrient concentrations over the same period. Drought conditions may have reduced water and nutrient uptake without significantly affecting leaf nutrient status.     

镉对茶条槭和五角槭光合作用和叶绿素荧光特性的影响

以北方阔叶树种茶条槭(Acer ginnala)和五角槭(Acer mono)2年生苗木为材料,采用土壤和风化砂混合物作为盆栽基质,设置0(CK)、10、50、100、200 mg·kg-1 5种土壤镉浓度,研究了土壤镉胁迫对苗木叶片光合作用和叶绿素荧光特性的影响.结果表明:随着土壤镉胁迫浓度增加,茶条槭净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)先升后降,胞间二氧化碳浓度(Ci)则先降后升,且均在10 mg·kg-1 Cd2+时达到峰值或谷值;同时五角槭的Pn逐渐降低,Ci持续升高,Gs和Tr则先升后降且均在10 mg·kg-1 Cd2+时达到峰值.随土壤镉处理浓度的增加,茶条槭和五角槭的Fv/Fm、Fv/F0和qN均呈先升后降趋势,ΦPSⅡ则均持续下降;qP在茶条槭表现为先升后降,而在五角槭则逐渐下降.所有指标(除Ci外)在随镉浓度的变化过程中,其上升幅度均为茶条槭大于五角槭,而下降幅度则为五角槭大于茶条槭.研究发现,重金属镉通过破坏或抑制光合作用过程来影响茶条槭和五角槭的生长,高浓度镉导致的Pn下降是由非气孔限制因素所致;茶条槭对土壤镉的耐性大于五角槭,100和50 mg·kg-1 Cd2+可能分别是茶条槭和五角槭对土壤镉污染的耐受极限.     

庙台槭形态特征补遗

对庙台槭花部形态特征补遗.     

基于均匀设计法优化三种槭树属植物高效快繁体系

以花楷械、青楷械和小楷械的嫩茎段为外植体,应用均匀设计法筛选最适合于嫩茎腋芽生长伸长同时生根的培养基．结果表明,最适合花楷械的培养基为：改良MS＋IAA0．10mg·L^-1＋GAa1．10mg·L^-1,再生率为98％;最适合青楷械的培养基为：改良MS＋IAA0．40mg·L^-1＋IBA0．10mg·L^-1＋NAA0．07mg·L^-1＋GA31．10mg·L^-1,再生率为96％;最适合小楷械的培养基为：改良MS＋IBA0．10mg·L^-1＋GA31．10mg·L^-1,再生率为94％．以再生植株的茎节为材料进行快繁的结果表明,在30-35d的一个培养周期内,增殖倍数达65以上．