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1.
沙地云杉生态型表观性状分化   总被引:2,自引:0,他引:2  
沙地云杉为内蒙古特有树种,干旱适应性强,已成为我国西部重要造林树种。在长期适应干旱生态条件的过程中沙地云杉形成了紫果型、绿果型和红果型等多种生态型。文章对各种生态型沙地云杉的表观性状分化进行了比较研究,可为沙地云杉生态型分化机理研究提供理论参考,对扩大沙地云杉造林面积和西部大开发的生态环境建设具有重要的指导意义。  相似文献   

2.
不同方法提取三种生态型沙地云杉总DNA的比较   总被引:1,自引:0,他引:1  
沙地云杉为内蒙古特有树种,干旱适应性强,是我国西部重要造林树种。在长期适应干旱生态条件的过程中沙地云杉形成了紫果型、绿果型和红果型3种生态型。前期研究证明:紫果型沙地云杉有更强的抗旱能力,绿果型抗旱能力弱,红果型处于二者之间,是一个比较典型的过渡类型。本文从分子生物学的角度,详细叙述了沙地云杉总DNA的提取过程、方法,并对已知的植物DNA提取方法作了针对性的改良;对实验过程提取DNA的影响作了分析。为今后针对进行沙地云杉的植物基因研究和生物工程打下基础,对扩大沙地云杉造林面积和西部大开发的生态环境建设具有重要的指导意义。  相似文献   

3.
沙地云杉(Piceamongolica)在中国的形成、分布和特性(英文)   总被引:2,自引:0,他引:2  
沙地云杉是中国的珍稀濒危树种。沙地云杉林是陆地上非常特殊的森林生态系统类型。它存在于我国森林草原过渡带,也是我国的农牧交错区。在本文中,我们讨论了沙地云杉的形成和分布,研究了沙地云杉的性质和特性。沙地云杉属于白扦云杉系列,是白扦云杉长期适应当地气候而演化的地方宗,然后形成异域的半种,最后形成分类种。沙地云杉林是森林草原过渡带上的超地带性顶极群落。  相似文献   

4.
沙地云杉林植物区系特征的研究   总被引:1,自引:0,他引:1  
根据野外调查,分析了沙地云杉林的植物区系成分,进行了种子植物的统计并得出结论:在沙地云杉林中,共有161种植物,分别属于49科,123属。其中1种蕨类植物,2种裸子植物,158种种子植物。共有10种地理成分分布类型,其中以达乌里-蒙古成分占优势,内蒙古自治区的特有成分只有沙地云杉一种。根据优势成分分析,发现在乔木层中只有沙地云杉和白桦达到存在度的4~5级,灌木层中只有黑果木旬子木达到5级。根据相似系数比较发现:沙地云杉林有56.8%的科、47.4%的属、47.4%的种与大针茅草原相同;有60.8%的科、22.3%的属、7.2%的种与长白山的典型暗针叶林相同,因此沙地云杉林仍然属于暗针叶林范畴。  相似文献   

5.
Assessment of genetic variation within and among populations is an essential parameter for the effective conservation of forest genetic resources. In this work, the genetic diversity within and among natural populations of the forest tree species Fraxinus angustifolia Vahl in Greece was studied using selected nuclear and chloroplast microsatellite DNA loci. Eight natural populations of F. angustifolia were identified in different locations of the mainland of Greece, and a total of 230 individuals were studied. High polymorphism was observed within populations, while the genetic differentiation among populations was moderate. Intra-population diversity was correlated with geographical coordinates, but no isolation by distance was observed. Of the three haplotypes identified, only one was dominant. Putative ancestral haplotypes were found at small spatial scales suggesting that population expansions could have originated in the region. This study located in sympatry haplotypes that in other parts of Europe are in allopatry, reinforcing the notion of population expansions from the south of Balkans including Greece. Suggestions for conservation and management of F. angustifolia are also reported.  相似文献   

6.
通过对红松(Pinuskoraiensis)、樟子松(Pinussylvestrisvar.mongolica)、彰武松(P.densifloravar.zhangwuensis)、赤松(P.densiflora)、欧洲赤松(P.sylvestris9个种源)、欧洲黑松(P.nigra)、小干松(P.contorta)、沙地云杉(Piceameyerivarmongolica)、北美云杉(Piceapungensglauce)、铅笔柏(Sabinaviginiana)定植在章古台生长表现,结合当地林龄超过20a的针叶树生长材料,进行分析得出:彰武松、樟子松、赤松表现最佳,可结合阔叶树种在平缓沙地及沙丘腹部营造混交林;沙地云杉、红松、铅笔柏可在立地条件较好的地方造林;欧洲赤松表现一般。  相似文献   

7.
多伦县沙地云杉混交林物种多样性研究   总被引:1,自引:0,他引:1  
以多伦县沙地云杉林3条样带的群落调查数据为基础,研究了沙地云杉混交林的物种组成结构,分析了3个典型群落乔木层、灌木层、草本层的物种多样性。结果表明:沙地云杉混交林植物种类丰富,乔木层、灌木层、草本层共有植物71种,群落垂直结构分层明显;多伦县沙地云杉与白桦混交林物种多样性较丰富,在群落梯度上,群落Ⅰ为52种,群落Ⅱ为45种,群落Ⅲ为47种,物种丰富度指数大小顺序为群落Ⅰ>群落Ⅲ>群落Ⅱ;群落的物种多样性指数变化规律大致相同,均为草本层>灌木层>乔木层;3个典型群落的物种均匀度指数变化规律基本一致,为乔木层最大,灌木层其次,草本层最小。通过对多伦县沙地云杉混交林物种多样性的研究,为加强沙地云杉生物多样性的保护和经营管理提供理论依据。  相似文献   

8.
INTRODUCTION Analysis of the amount and distribution of genetic variation within and among populations of a species can increase the understanding of the historical processes underlying the genetic diversity (Dumolin- Lapegue et al. 1997) and can also provide important basic information for breeding programmes and for the establishment of programmes to conserve genetic resources. Moreover, information on the genetic structure allows for a more representative sample of the species’ gene p…  相似文献   

9.
The mode of chloroplast inheritance was investigated in the four Australian conifer species; Callitris columellaris, C. intratropica, C. gracilis and C. verrucosa (Callitroideae, Cupressaceae), as a basis for future use of chloroplast genetic markers for the genus. Open-pollinated seeds and the foliage tissue of the mother trees were collected from one population per species, in which two distinct chloroplast haplotypes at the trnL (UAA) 5′ exon–trnF (GAA) region were co-distributed. In total, the DNA sequences of the chloroplast fragments in 255 samples were determined, and the haplotypes of the germinated seedlings and the mother trees were compared. Among the 16 mother trees examined across all species, 12 trees were shown to have produced at least one offspring with a different haplotype from the mother, indicating the occurrence of paternal inheritance of chloroplast in the fertilization processes. In binomial GLMM analyses, the haplotype of mother trees in C. columellaris, C. gracilis, and C. verrucosa did not significantly affect those of their offspring, and the predicted frequency of seedlings’ haplotypes was compatible with the observed frequency in adult canopy trees. These findings provide a genetic support that paternal inheritance of chloroplast DNA via pollen dispersal would be dominant in the Callitris species.  相似文献   

10.
沙地云杉生态学研究进展   总被引:1,自引:0,他引:1  
沙地云杉以其独特的生物学特性及分布生长在干旱的沙质土地上而引人注目,其种的分类地位、个体生态学、种群生态学及群落生态学等方面得到了广泛地研究。但是在自然和人为活动的综合影响下,沙地云杉仍存在着明显的退化趋势,其种群演替和生态学特性仍需进一步地深入研究。  相似文献   

11.
Populus caspica Bornm.(section Leuce and subsection Albida), one of the most endangered endemic tree species in the Hyrcanian Forest in Iran, has numerous morphological characteristics that are closely similar to Populus alba; to clarify their taxonomic relatedness and genetic differentiation and thus inform conservation strategies, we used the noncoding regions of chloroplast DNA(cpDNA; trnL-F and trnH-psbA) and the internal transcribed spacer(ITS). Leaf samples were collected from six populations across northern Iran. cpDNA and ITS fragments were amplified by universal primers using the PCR technique and directed sequencing. The results showed that P. caspica is genetically differentiated from P.alba, and two ITS variants were detected within some P.caspica individuals. Conflicts between topologies from ITS and plastid genomes were observed. High differentiation of P. caspica from the other Populus species shown in this study confirmed the diverging taxonomic status of this endangered species. We recommend in situ conservation measures(e.g., protected areas) for at least several populations of this species, especially in the plain regions of the Hyrcanian forest.  相似文献   

12.
随着公共数据库信息量的不断丰富,桉树基因组序列的公布数据也逐渐增多。本文利用NCBI数据库下载的21条桉树叶绿体matK基因序列进行分析研究,发现软件构建的系统发育树树与学术界承认和使用的Hill&Johnson形态分类学状态有一定的差异,可能与下载的序列数据不够全面、覆盖的信息量不能代表该种基因组序列有关。通过对MP法、ML法、NJ法、UPGMA法和Bayes法等5种方法构建系统发育树、序列信息位点分析和形态学分类状态的比较,UPGMA法构建的系统发育树与序列的信息位点分析结果较为一致,MP法构建的系统发育树较为可信,但进一步的信息确认还需后续的研究证实。  相似文献   

13.
科尔沁沙地极端气候条件对外来树种影响的研究   总被引:4,自引:4,他引:0  
科尔沁沙地在1999~2002年出现了持续时间最长的干旱期和极端最低气温。一些外来树种发生了树冠干枯和植株枯死。遭受冻害的外来树种有华山松、侧柏、刺槐、臭椿、槐树、大扁杏和山楂等18种。在干旱期间杨树固沙林枯死率比较高,达8%~33%,樟子松耐旱抗寒,林分枯死率比较低,为0~6%。最不耐旱的树种是落叶松,其次是沙地云杉和枯枥木花曲柳。比较耐旱的树种有油松、东宁赤松、怀槐、暴马子、榆树、刺榆和桑树。  相似文献   

14.
干旱荒漠区沙地云杉幼苗越冬措施效果分析   总被引:1,自引:0,他引:1  
在干旱荒漠区,对1年生沙地云杉容器苗在温室和自然条件下分别设置实验,对其越冬措施效果进行了比较分析。在室外条件下对沙地云杉幼苗采用土壤、沙子、塑料、塑料薄膜、麦草、树叶为覆盖材料,同时,对沙地云杉埋土越冬采用了土壤、沙子2种材料,设置了不同的覆盖厚度。研究不同覆盖材料和覆盖厚度对苗木越冬保苗率的影响。研究结果表明:(1)覆土对沙地云杉幼苗的保苗率明显高于覆沙的保苗率,覆土厚度与保苗率关系密切(R2=0.916 4),覆土的厚度为10~15 cm保苗效果最好;(2)各种覆盖材料相比,覆土对沙地云杉幼苗越冬效果最好。  相似文献   

15.
Abstract

Knowledge of the canopy lichen flora of managed forests is poor, but needs more focus since, for example, slash (tops, branches and twigs) harvest for biofuel may pose a threat to epiphytic lichen diversity. This study compared lichen species richness, density and composition between stems, tops, branches and twigs of mature Norway spruce (Picea abies) and aspen (Populus tremula) in managed boreonemoral forests in south–central Sweden. The stems were also compared with the slash fractions pooled together. All comparisons were made separately for each tree species. In total, 30 lichen species were found on Norway spruce and 46 on aspen. No significant differences in species richness or species density between fractions were found for Norway spruce, whereas aspen tops were significantly less species rich and species dense than the other fractions. Moreover, aspen slash was significantly more species dense than the stem. The lichen species composition of the stems clearly differed from that of the tops, branches and twigs in both tree species. Thus, lichen communities other than those removed with stems by conventional forestry are removed from the stands owing to slash harvest. However, these species are rather common and widespread in Sweden. The impact of slash harvest on the epiphytic lichen flora may therefore be of minor importance in forests established after clear-cutting or on former arable land.  相似文献   

16.
半干旱地区沙地云杉播种育苗试验   总被引:3,自引:0,他引:3  
通过沙地云杉播种育苗,研究了不同播种时间、不同遮阴方式、不同播种方式对播种出苗量和生长的影响,同时通过对地温的研究。阐明了生态条件对苗木生长的影响。最终提出在嫩江平原区限制沙地云杉育苗的主要因子和适时早播、采用高床、条播方式等有利于提高育苗质量的方法。  相似文献   

17.
Picea Mill.species are important components of boreal and subalpine forests.They have a wide geographical range in the Northern Hemisphere,extending from the Eurasian continent to North America.In this study,publications on Picea species from 2002 to 2016 were identified via the Web of Science(WoS) and the China National Knowledge Infrastructure(CNKI) databases,and subjected to relationship network visualization using CiteSpace software.This study represents the first such analysis of Picea and provides a reference for bibliometrics in forest tree species research.The results show that the total number of publications on Picea archived in WoS was20,958 and that the number of papers published annually has increased over time,peaking at 1725 in 2013.The studies were mainly conducted in North America,Europe and Asia;among them,Canada published the most papers and showed the strongest betweenness centrality(0.11).Among research institutions,the Swedish University of Agricultural Sciences in Uppsala had the highest publication record.The research contributions of the Chinese Academy of Sciences,the Chinese Academy of Forestry,and Beijing Forestry University have improved rapidly in recent years,greatly enhancing the international impact of Chinese research in this field.The research contents were grouped into five categories:forest ecosystems,pest resistance,extraction and functional analyses of active ingredients from various plant organs,nursery and afforestation techniques,and timber quality research.In China,the number of papers from the CNKI database was4532,increasing at an even pace.The research topics on Picea included forest ecosystems,seedling and afforestation techniques,basic studies on individual species and populations,and pests and diseases.Within and outside China,hotspots in Picea research included the relationships between Picea and environmental factors,and the genomic sequences of Picea.  相似文献   

18.
果尔作为一种应用较多的化学除草剂,已经在苗圃中广泛应用。通过试验得出结论:一年生针叶树出苗前采用果尔土壤处理除草,对红松效果最好,其次是红皮云杉和樟子松。二年生针叶苗木生长期采用果尔土壤处理除草,对红皮云杉效果最好,其次是红松和樟子松。因此说果尔是林区比较理想的除草剂。  相似文献   

19.
云杉属的种和种源选择试验   总被引:1,自引:0,他引:1  
于湖北省宜昌市夷陵区国有樟村坪林场营造云杉属5个种18个种源的种和种源试验林,进行云杉属的种和种源选择试验。结果表明:5种云杉18个种源的造林成活率为76%~92%,平均85.0%;保存率为27%~73%,平均46.1%。欧洲云杉的平均成活率和平均保存率最高,分别达89.0%和60.0%,其中4号、6号2个种源的平均成活率和平均保存率分别达87.5%和67.0%。6年生欧洲云杉的平均树高比其它4个种的平均树高生长量提高36.85%,其中最优良种源是4号和6号种源,该2个种源的平均树高生长量比5号和7号2个种源提高26.63%;4~6年生林不同种源的保存率与历年生长量的差异均达到了显著或极显著水平;4年生林树高和地径之间、5年生林树高和冠幅之间、6年生林树高和地径之间的相关系数均在0.5以上,指标间具有极显著的正相关关系。  相似文献   

20.
沙地云杉种子育苗试验   总被引:3,自引:0,他引:3  
应用正交试验设计的方法,从播种基质、覆盖材料、覆盖厚度和种子处理4个因素出发,探讨了沙地云杉播种育苗中的一些主要影响因子.结果表明:种子处理对播种育苗试验结果的影响最大,其余因素对播种育苗存在一定的影响.但差异性均较小.通过试验结果分析选择出最佳的播种育苗方案为:以细沙作为栽培基质和覆盖材料.覆沙厚度0.3 cm,种子...  相似文献   

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