针叶植物

For the conservation of forest, the structure and floristic composition of coniferous forest have been studied.

贺兰山针叶林是我国西北地区珍贵的森林生态系统，本文通过研究其结构特征和植物种类组成，为森林保育提供建议。

Forest types had significant influences on the nutrient characteristics of plant foliage, litter quality and most of the soil properties, showing significant difference between the deciduous forests and the conifer forests, the two types of conifer forests dominated by pine and larch, respectively.

林型对植物叶片养分特征、叶片凋落物品质指标、土壤的大多数理化特性都有显著影响，其中，落叶阔叶林与针叶林之间的差异最为明显，优势种不同的针叶林之间也不同程度地存在差异。

Any of several deciduous, coniferous trees of the genus Larix, having needlelike leaves clustered on short shoots and heavy, durable wood.

落叶松属植物一种落叶树属的落叶性针叶树木，有成簇状针叶和重而坚硬的木质

Taxaceae A family of evergreen coniferous trees and shrubs, the yews, with needlelike or linear leaves.

紫杉科：包括常绿针叶树、常绿灌木、紫杉在内，具针叶或线性叶的一个植物科。

Seed germination rate and germination speed and seedling root length are more sensitive to the extract than the other index. Allelopathy on Ligularia sagitta is different among the species tested in this study, Thermopsis lanceolata, Stellera chamaejasme, Aconitum sinomontanum, Ipornoea cairica, Ajania tenuifolia and Wedelia trilobata show better result. New natural herbicides may be developed from these 6 species.

不同供体植物对箭叶橐吾化感抑制程度不同，披针叶黄华、狼毒、高乌头、五爪金龙、细叶亚菊和南美彭琪菊的作用效果非常显著（综合化感效应指数M0.50），这6种植物有望开发天然除草剂。

On the other hand, some deciduous gymnosperms including Ginkgoales, and the presence of growth rings in the fossil secondary wood, indicate seasonal changes.

植物组合中以丰富的热带及亚热带型植物为主要特点，未发现针叶类型的植物，说明早白垩世穆棱组沉积时，该地区的气候温暖湿润；另一方面，落叶的银杏类和松柏类，以及裸子植物木化石中具有清楚的生长轮，又说明该地区的古气候存在着季节变化。

The results showed that conifers were the closest relatives of Ginkgo with gnetales being nested within conifers, and cycads were the most primitive in gymnosperms.

多基因综合分析表明，银杏与针叶植物的亲缘关系最为亲近，买麻藤为针叶类内起源，苏铁为裸子植物中最原始的类群。

Palynoflora was characterized by the predominant appearance of gymnospermous elements.

在此基础上划分了3个孢粉植物群－气候期，当时植被是以松科植物为主组成的针叶林植被，从早期到中期喜湿热的蕨类植物和落叶阔叶树种增多；气候从凉爽湿润的南温带→半湿润偏干的北亚热带→偏干的南温带的转变。

A favorite and easily incorporated technique for creating garden bones is to use evergreens, especially dwarf conifers.

一个通常喜欢和方便结合技术创造庭院主题的方法是用常绿的植物，尤其是矮小的针叶类植物。

From 6860 to 3170 cal.yr BP,semi-desert steppeexpanded,regional montane forest steppe retreated,suggesting a prolonged warm and dryclimate.Between 3170 and 2340 cal.yr BP,regional forest steppe expanded whereassemi-desert steppe retreated,indicating the climate became cool and wet gradually and thehumidity reached the maximum at the end of this stage.During 2340～1600 cal.yr BP,Poaceae steppe dominated whereas wetland meadow expanded and the montane forest stepperetreated,suggesting a cool and wet climate prevailed,wormwood grass steppe prevailed andthe climatic instability increased after 1600 cal.a BEThe climate and environmental reconstructions by pollen were supported by the diatomrecords.A relative high lake level and moister climate prevailed between 8660 and 7230 cal.yr BP as inferred by the dominance of planktonic diatom genera and high planktonic/benthicratio (〉40).low lake level and dry climate sustained during 7230～2330 cal.yr BP assuggested by the low abundance of planktonic diatom and low planktonic/benthic ratio ～20and the lake returned to high level during 2330～930 cal.yr BP as inferred by there-dominance of the planktonic diatom and the high value of palnktonic/benthic ratio.The pollen-based climate reconstruction was also consolidated by the grain size andPediastrum concentration records.

Ugii Nuur湖周围现代孢粉研究表明：松属为空气传播的外来花粉，其含量变化可能指示了远山森林草原发育状况；禾本科具显著低代表性，母体植物建群时含量通常在10％以下：藜科花粉含量可以指示区域气候干旱程度。2、以现代孢粉研究为基础、可靠AMS~(14)C年代为框架，Ugii Nuur孢粉记录高分辨率地重建了蒙古国中部地区过去8660 cal.yr BP以来的植被和气候变化。8660～7800 cal.yr BP研究区植被为禾草草原，湖畔及河谷低地发育苔草草甸，远山发育松属针叶林和森林草原，气候温和略湿润；其中8350～8250 cal.yr BP湿生草甸扩张，旱生植物成分减少，气候凉湿。7800～6860 cal.yr BP旱生成分增加，气候转向暖干。6860～3170 cal.yrBP半荒漠草原扩张，远山森林草原退缩，山地草原和河谷及湖畔湿生草甸退缩，气候持续暖干。3170～2340 cal.yr BP半荒漠草原退缩，远山森林草原扩张，气候转凉变湿，末期湿度条件达最佳。2340～1600 cal.yr BP禾草草原发育，湖畔及河谷低地湿生草甸扩张，远山森林草原略有退缩，气候总体较凉湿。1600 cal.yr BP以来研究区发育禾草-冷蒿草原，气候波动较大。

The concept of equivalent rotationally rigidity is offered and the formula of rotationally rigidity is obtained.

主要做了如下几个方面的工作：对伸臂位于顶部的单层框架—筒体模型进行分析，提出了等效转动约束的概念和转动约束刚度的表达式。

Male cats normally do not need aftercare with the exception of the night after the anesthetic.

男猫通常不需要善后除了晚上的麻醉。