查询词典 Betula

Biomass in the rain forest was far more than that in the plantation of 12 years,especially for the shrub layer.But the biomass of litterfall collected in the plantation was greater than that of the rain forest for the reason that Betula alnoidis defoliated in dry seasons.9 Four years observation found that soil bulk density tended to increase first, then decrease after planting trees;total soil porosity and non-capillary porosity tended to decrease and after few years they recovered to different degrees;the soil cation exchange capacity for all forest types increased;in the soil of 0-30cm depth,soil salt saturation tended to decrease;nutrient content in the soil of 0-60cm depth in the young stand tended to decline;soil effective P,effective K and N contents all tended to decrease.

山地雨林的总生物量远远大于10年生的西南桦人工林，其中灌木层的相对差别尤其巨大。94次的观测发现，人工林栽植后，土壤容重一般呈现一个先上升后下降的特点；而土壤非毛管孔隙度、土壤总孔隙度大多呈下降趋势，几年后有不同程度的恢复。

In order to investigate the effect of different parts and radial directions on the mechanical properties and dir-dried density of plantation wood,the mechanical properties and air-dried density of plantation-grown Castanopsis hystrix and Betula alnoides at different parts and radial directions were studied.

为了研究树木南北向与径向位置的变化对人工林木材力学性质与气干密度的影响，该文通过对红锥、西南桦人工林木材南北向、近髓心和近树皮2个不同径向位置的力学性质以及气干密度进行测定，分析了南北向和不同径向位置2个因素对两种木材力学性质和气干密度的影响，以及木材密度与抗弯强度、抗弯弹性模量、顺纹抗压强度的相关性。

Keywords Castanopsis hystrix;Betula alnoides;plantation wood;mechanical property;air-dried density

红锥； 西南桦；人工林木材；力学性质；气干密度

To clone the calmodulin genes from Karelinia caspica, Kalidium foliadum and Betula halophila in Xinjiang, designed primers were used to amplify 450-bp cDNA fragments with RT-PCR.

提要 采用RT-PCR扩增的方法，从新疆盐生植物花花柴、盐爪爪和盐桦中分别克隆获得了450 bp的cDNA片段。

County is rich in mineral resources, with proven gold, silver, copper, coal, clay, more than 10 kinds of marble, etc.; there are antelope, zi , otters, giant salamander, deer, and other rare animals microphylla; have yew, iron Sequoia, Ginkgo, camphora, Acacia, Pinus and other rare species; have tabulaeformis, pine, larch, red wood tree species Betula, etc.; produce velvet, musk, Polyporus, five Faeces, gastrodin, bark, yellow more than 400 kinds of Chinese medicinal herbs such as ginger.

县境内有丰富的矿产资源，已探明的有金、银、铜、煤炭、陶土、大理石等10多种；有羚羊、獐子、水獭、大鲵、麝、锦鸡等珍稀动物；有红豆杉、铁杉、银杏、香樟、合欢、白皮松等珍稀树种；有油松、华山松、落叶松、红桦等用柴树种；出产鹿茸、麝香、猪苓、五灵脂、天麻、杜仲、黄姜等中药材400多种。

In this study, based on the Rnl, extinction coefficient k, transition coefficient of canopy layer stomatic resistance K', aerodynamics resistance ra and rc calculated with the data of Rn, LAI, rsi, the daily transpiration variation of Picea purpurea, Larix principisrupprechtii, Hippophae rhamnoides ,Betula platyphylla and Populus cathayana were studied in Datong County, Qinghai Province. Comparing with the practical transpiration variation measured by Li1600 Steady Porometer, the relative error of this model was less than ±15%, and the results were stabilized and tested by precision analysis.

本研究通过对Rn、LAI、rsi的实地观测，确定了林冠截流净辐射、消光系数、冠层阻力转换系数、空气动力学阻力和冠层整体气孔阻力，对青海大通地区紫果云杉、华北落叶松、沙棘、白桦和青杨的日蒸腾过程进行了模拟，与用快速称重法订正的Li1600稳态气孔仪实测蒸腾结果对比，模拟的相对误差在±15%以内；模型敏感性分析发现，温度、LAI以及rsi是决定模拟结果的主要参数，模型对各参数变化反应不敏感。

The cDNA (BplPAL1) encoding phenylalanine ammonia-lyase were cloned from Betula platyphylla by reverse transcription polymerase chain reaction and 5' and 3' rapid amplification of cDNA ends, which contains an open reading frame (2322 bp) encoding 773 amino acids. The amino acid sequences contain two functional domains of PAL-HAL and PAL, and the sequence of enzyme active site, which has 60%~73% of consistency with other five plant species and the consistency with Rhizophora mangle is the highest (73.1%).

利用RT-PCR和RACE技术从白桦中克隆了编码苯丙氨酸解氨酶的cDNA，其2322bp的ORF编码773个氨基酸，其推导的氨基酸序列包含PAL-HAL和PAL2个功能域以及酶活性中心序列GTITASGDLVPLSYIA，该序列同其它5种植物的序列一致性为60%~73%，其中与美洲红树最高为73.1%。

According to the SLA and LDMC of tree layer, the five communities can be classified into three groups: the first group consists of Betula dahurica and Populus davidiana, the second group contains mainly Quercus liaotungensis, and the third group consists of Juglans mandshurica and Tilia mandshurica.

依据乔木层的SLA和LDMC将5种群落分成3类，第一类是黑桦林和山杨林，第二类是辽东栎林，第三类是胡桃楸林和糠椴林。

The effect of humic acid with the concentration of 850mg/L on improving the drought-resistance of Populus alba x Populus breolinensis seedlings was very obvious, and favorable regulative effects of humic acid with the concentrations of 850 and 650 mg/L on Ulmus pumila seedlings were also observed, but the effect of humic acid on Betula platyphylla seedlings was not distinct.

浓度为850 mg／L的黄腐酸对提高银中杨苗木抗旱性效果明显，浓度为850 mg／L和650mg／L的黄腐酸对白榆苗木抗旱性均有良好的调节作用，黄腐酸对白桦苗木抗旱性的调节作用不明显。

However remarkable impacts were observed in the plantation in terms of community physiognomy,community structure,species composition,species richness,and biomass accumulation.1 Planting trees made community structure simple.Betula alnoidis plantation had three layers including a dominant arbor layer,a complex and well developed shrub layer and a poorly developed vine layer.The arbor layer contained few species and had a single layer.The mountain rain forest had 4 layers including the dominant arbor layer,shrub layer,grass layer and vine layer.The vine layer was well developed and very rich in species composition,and the arbor layer contained as many as 38 species that could be grouped into 3 layers.2 Sequenced by the important value,main species for the plantation and the nature forest were totally different,and the plantation had one dominant species while the nature forest contained many dominant species.3 Planting trees changed the community physiognomy.

但是人工种植西南桦林对群落的季相外貌、群落的结构、物种组成、物种丰富度以及生物量等方面有较大的影响。1人工造林使得群落结构简化，西南桦人工林的层次结构有3层，以乔木层占优势，并且有种类多而发达的灌木层，同时，藤本植物欠发达，但是乔木层树种单一，明显仅有一层；山地雨林的层次结构有4层，以乔木层占优势，还有灌木层、草本层和藤本植物，藤本植物种类多，十分发达；乔木层树种丰富，可达38种，乔木层还可分为3层。2人工造林较大程度地改变了群落的物种组成，根据重要值的大小排列，人工林和天然林的主要物种组成已经完全不同；并且人工林单优树种明显，而天然林就含有较多的优势树种。3人工造林改变了群落的外貌。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了