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1.
将产于中国海南的Cayratia mollissima var.lanceolata C.L.Li.提升为种:Cayratia lanceolata(C.L.Li)J.Wen&Z.-D.Chen(狭叶乌蔹莓),本种与产于马来西亚和印度支那的C.mollissima在果实与叶形态上差异显著。  相似文献   

2.
豆科黄结属模式及其相关种名的考证   总被引:4,自引:0,他引:4  
长期以来,Termopsis lanceolata R.Br.被误认为是黄华属的模式。根据有关文献考证和国际植物命名法规,作者为认T.;lanceoltata是一个不合法名,黄华属的合法模式应为Thermopsis Lupinoides(L.)Link.分布于东北亚,花具互生花的黄华长期被误定为T。lupinoides(L.)Link,应更正为Thermopsis fabacea(Pall)DC.。  相似文献   

3.
Ophioglossum yongrenense Ching ex Z. R. He et W. M. Chu, sp. nov.Species nova aspectu inter O. kawamuram Tagawa et O. parvum Nishida et Kurita Japonicae, differt a priore frondibus pro parte laminis sterilibus praeditis (in illa frondibus omnino laminis sterilibus non praeditis), a posteriore frondibus pro parte laminis sterilibus non praeditis (in O. parvo Nishida et Kurita frondibus omino laminis sterilibus praeditis).……  相似文献   

4.
To understand the geographical patterns of genetic variation in freshwater fishes in western Japan, the genetic structures of populations of Tanakia lanceolata and T. limbata (Teleostei, Cyprinidae) in this area were investigated using mitochondrial DNA (mtDNA) cytb sequences. Neighbor-joining trees of mtDNA haplotypes revealed four and three genetically divergent groups in T. lanceolata and T. limbata, respectively. Each group was restricted to one or the other of the geographical regions in the area studied. The patterns of geographical divergence in the two species showed some similarities, which seem to reflect common historical events experienced by freshwater fishes distributed in western Japan. On the other hand, dissimilarities were also found in the patterns, indicating that species-specific historical processes also occurred. Within one region, T. lanceolata was less differentiated than T. limbata, suggesting a difference in the dispersal abilities of the two bitterlings. In addition, several individuals in Kunichika River on Shikoku island were morphologically identified as T. lanceolata but had mtDNA haplotypes of T. limbata. We tentatively suggest that these individuals are hybrids of the two species, but further studies employing nuclear markers are necessary to validate this hypothesis.  相似文献   

5.
披针叶黄华(Thermopsis lanceolata)是我国西部地区早春重要野生蜜源植物,也是一种重要的固沙植物,然而对其繁殖特性的研究甚少.本文在系统调查披针叶黄华的访花昆虫基础上,确定其主要传粉昆虫种类、访花行为、传粉过程以及日活动规律,以期揭示主要访花者行为对其有性繁殖的影响.作者在内蒙古毛乌素沙地设置1个10m×10 m的样方,于2010和2011年在披针叶黄华盛花期,采用目测、拍照和摄像等方式对传粉昆虫进行观测,记录样方内主要访花昆虫种类、数量、访花行为及日活动规律.研究表明,大和切叶蜂(Megachile japonica)和戎拟孔蜂(Hoplitis princeps)是披针叶黄华的主要传粉者,但两种昆虫的访花频率存在显著差异;晴天时,大和切叶蜂在19:00-13:00和16:00-18:00出现两个活动高峰,而戎拟孔蜂只在11:30-16:30出现1个活动高峰,两种蜂的访花活动高峰期存在互补关系.大和切叶蜂访花同时具有盗蜜行为,但其盗蜜行为对披针叶黄华的结籽率没有显著影响.根据种群数量、访花频率综合判断,大和切叶蜂是披针叶黄华优势传粉蜂.  相似文献   

6.
本文报道舟皮盘菌属一新组合,即汉德尔舟皮盘菌[Ploioderma handelii(Petrak)Y.R.Lin et Hou comb.nov.]。该菌在杉木[Cunninghamia lanceolata(Lamb.)Hook.]球果鳞片和针叶上发生,分布于安徽、江苏、湖南、广西和贵州等省区。  相似文献   

7.
Cunnighamia unicanaliculata D. Y. Wang et H. L. Liu and var. pyramidalis D. Y. Wang et H. L. Lin, two new taxa recently found in south-western Sichuan Province of China, have both a very restricted yet sympatric geographical distribution, including Dechang and Miyi districts.[7] There is a debate as regards the specific status of C. unicanaliculata. A comparative karyological investigation, including chromosome numbers, karyotype analyses and measurements of nuclear volume and DNA contents, was under- taken in order to shed some light on the phylogenetic relationships between these taxa and C. lanceolata (Lamb.) Hook. The kaxyotype formulas of the above two taxa and C. lanceolata are as follows: C.unicanaliculata; K(2n) = 22 =L8m+ S12m+S2sm; C. unicanaliculata var. pyramidalis: K(2n)= 22= L8m +S10m+S4sm; C. lanceolata (Type A): K(2n) =22 = Lsm+ S14m S2sm; C. lanceolata(TypeB): K(2n) = 22 = L8m + S14m . Frown the above karyotypes, we have found that C. unicanaliculata and var. pyrami- dalis, which are very similar to each other, are closely related to C. lanceolata (Type B), but seem more strongly differentiated in the following respects: (1) the former posses- sing 1--2 pairs of chromosomes with submedian primary constrictions each, while the latter with all chromosomes possessing median primary constrictions; (2) the satellites of the former being always located on the 4th pair of chromosomes, whereas the position of satellites of the latter varying with geographical distribution, being usually on the 1st and 4th pairs of chromosomes; (3) B-chromosomes being present in the latter (predominantly in the geographical races of southwestern China) but not seen in the former; (4) the average chromosome volume of C. unicanaliculata var. pyramidalis being 623.44, while those of the four geographical races of C. lanceolata being 667.2–796.0; (5) the comparative DNA amount of C. unicanaliculata var. pyramidalis being 5.54, while those of the various geographical races of C. lanceolata being 6.20–7.67. Upon an overall comparison of the data with regard to karyology, geographical distribution, ecology, morphology and isoenzymic patterns of the taxa in question, we come to the following conclusions. Cunninghamia unicanaliculata and var. pyramidalis are most likely taxa originated from natural populations of C. lanceolata. The extreme environmental conditions of the habitats axe thought to have played an important role in the production of these two new taxa. An elevation of over 2000 meters and the periodical aridity of climate of the habitat, which differed remarkably from those of C. lanceolata, made possible the isolation of alternative populations, accompanied by selection for adaptation to extreme environments. But the differences between these two newly found taxa and C. lanceolata are karyologically minor and morphologically quantitative and tend to display a more or less continuous variation pattern. It is, therefore, suggested that they are probably geographical races or ecotypes of C. lanceolata, and are not distinct enough from the latter to warrant specific status. It seems best to treat both C. unicanaliculata and var. pyramidalis as infraspecific catorories of C. lanceolata.  相似文献   

8.
The type of Opegrapha pyrenocarpoides is conspecific with Tylophorella polyspora , and the new combination T. pyrenocarpoides is made. Tylophorella has been placed in Caliciales s. lat., but shows similarities both to Pyrenulales and Arthoniales. T. pyrenocarpoides is reported new to Africa.  相似文献   

9.
杉楠混交与人工杉木林自养机制的恢复   总被引:10,自引:3,他引:10  
自养机制的形成是人工林可持续经营的目标之一。本研究通过混交模拟杉木人工林不同恢复阶段林分,观察比较发现从退化的杉木林阶段到地带性树种比例较低的混交林、地带性树种比例较高的混交林和地带性树种纯林阶段凋落量、N、P、K、Ca和Mg5种元素的归还量逐渐增加,特别是5种养分元素的循环速率也不断增大,其中N、Mg的循环速率由杉木纯林的0.1左右增大到火力楠纯林的0.5以上,与此同时林分土壤有机质含量和养分含  相似文献   

10.
自养机制的形成是人工林可持续经营的目标之一.本研究通过混交模拟杉木人工林不同恢复阶段林分,观察比较发现从退化的杉木林阶段到地带性树种比例较低的混交林、地带性树种比例较高的混交林和地带性树种纯林阶段凋落量、N、P、K、Ca和Mg5种元素的归还量逐渐增加,特别是5种养分元素的循环速率也不断增大,其中N、Mg的循环速率由杉木纯林的0.1左右增大到火力楠纯林的0.5以上,与此同时林分土壤有机质含量和养分含量也不断增加,表明退化杉木人工林在恢复过程中随着林内地带性火力楠树种混交比例的增加,林分的自养机制逐渐获得重建.从杉木人工林可持续经营角度来看,杉阔混交比例的确定应以林分自养机制的形成和土壤养分状况的改善为标准.  相似文献   

11.
连栽土壤对杉木幼苗生长影响的研究   总被引:5,自引:0,他引:5  
连栽土壤对杉木幼苗生长影响的研究马越强廖利平杨跃军汪思龙高洪陈楚莹(中国科学院沈阳应用生态研究所,110015)刘更有(湖南省会同县林科所,418307)EfectsofReplantSoilontheGrowthofC.lanceolataSedl...  相似文献   

12.
Thunbergia colpifera and Staurogyne parvicaulis are described as new species. Staurogyne longeciliata is a synonym of S. lanceolata , and so is S. lanceolata var. scabridula. Ebennaiera subcapitata is still kept in Staurogyne setigera. Staurogyne malaccensis is a synonym of S. setigera , and so is S. malaccensis var. stenophylla .  相似文献   

13.
Fifteen new taxa of the genus Saxifraga (Saxifragaceae) are described from China. They are Saxifraga erectisepala J. T. Pan, S. sublinearifolia J. T. Pan, S. rizhaoshanensis J. T. Pan, S. gedangensis J. T. Pan, S. sheqilaensis J. T. Pan, S. egregioides J. T. Pan, S. caveana W. W. Smith var. lanceolata J. T. Pan, S. subtsangchanensis J. T. Pan, S. brachypodoidea J. T. Pan, S. oreophila Franch. var. depaoshanensis J. T. Pan, S. subsediformis J. T. Pan, S. nangqenica J. T. Pan, S. medogensis J. T. Pan, S. paiquensis J. T. Pan and S. daochengensisJ. T. Pan.  相似文献   

14.
氮-硫沉降对邓恩桉及杉木人工林凋落物C和N残留率的影响   总被引:1,自引:0,他引:1  
采用二次正交回归旋转设计,以Na2S04为硫源、46%CO(NH2)2为氮源模拟氮一硫沉降,分析了不同氮一硫沉降水平下邓恩桉(Eucalyptus dunnii Maiden)和杉木[Cunninghamia lanceolata(Lamb.)Hook.]人工林凋落物中C和N残留率的动态变化,并采用Olson指数模型对c和N分解模型进行拟合。结果表明:在不同氮一硫沉降水平下,在1年内随处理时间延长邓恩桉和杉木凋落物的C和N残留率总体上均呈下降趋势;且N较难释放,总体表现为“释放一富集一释放”的动态过程;但在不同氮一硫沉降水平下及不同处理时间凋落物中C和N残留率均有极显著差异(P〈0.01)。凋落物中C和N分解的Olson指数模型的相关性总体上达到极显著或显著(P〈0.05)水平;邓恩桉和杉木凋落物中C和N的平均分解系数分别为0.877和0.208、0.704和0.600,平均周转期分别为3.148和15.877a,4.090和4.947a,显示凋落物中C释放速率大于N,杉木凋落物的C周转期大于邓恩桉但其N周转期则小于后者。在Na2SO4164kg·hm-1·a-1的水平下,氮沉降对邓恩桉凋落物的C和N释放及杉木凋落物的N释放有促进作用,但对杉木凋落物的C释放有抑制作用;在46%CO(NH:):150或256kg·hm-2·a-1。的水平下,硫沉降也具有同样的作用。随分解时间的延长,邓恩桉凋落物的C/N值呈波动但总体减小的趋势,而杉木凋落物的C/N值呈波动趋势;但在不同氮一硫沉降水平下凋落物的C/N值均有极显著差异,且邓恩桉凋落物C/N值的变化幅度总体上大于杉木凋落物。  相似文献   

15.
为了探究贺兰山不同乔灌草的光合生理特性及其对自然环境的适应特性和机制,该研究采用Li-6400XT便携式光合仪测定了贺兰山10种乔灌草气体交换参数及自然环境因子并分析其相关性.结果表明:(1)净光合速率(Pn)日均值从大到小为披针叶黄华>灰榆>山杨>栒子>冰草>油松>小叶忍冬>小檗>青海云杉>苔草,从不同生活型来看表现...  相似文献   

16.
杉木林自疏过程密度调节规律的研究   总被引:18,自引:0,他引:18  
提出了森林自然稀疏过程中密度调节规律新模型,应用收缩扩张算法以山杨、云南松等树种森林自疏过程中密度资料对新模型进行了验证。验证结果表明:所提出的森林自疏规律模型能很好拟合实际的观测资料,具有良好的使用价值;所采用的非线性方程最优拟合方法是科学的,从而丰富了该领域的研究方法。交提出的森林自然稀疏过程密度调节规律模型应用于杉木林自疏过程密度变化规律研究,效果很理想,可为杉木林经营管理提供参考。  相似文献   

17.
杉木人工林取代天然次生阔叶林对土壤生物活性的影响   总被引:17,自引:0,他引:17  
对我国亚热带南、中、北3个区带杉木人工林与天然次生阔叶林表层土壤化学性状、土壤生物活性特征进行研究.结果表明,杉木人工林取代天然次生林阔叶林后表层土壤总有机碳含量下降31.51%~58.24%,土壤全氮、全磷、pH值以及土壤C/N、C/P比亦呈下降趋势;杉木人工林取代天然次生阔叶林后表层土壤细菌、真菌数量减少;土壤脲酶、蔗糖酶、过氧化氢酶和脱氢酶活性下降,而土壤多酚氧化酶活性增加8%~40%;杉木人工林与天然次生林阔叶林相比,土壤呼吸强度下降51.15%~54.48%.相关分析发现,土壤总有机碳与土壤多酚氧化酶活性呈负相关(R=-0.723,n=18),与土壤全氮、全磷及其它土壤酶活性呈正相关.杉木人工林取代天然次生林阔叶林使林内表层土壤质量恶化.杉木人工林土壤有机质丢失是导致杉木人工林土壤养分减少、土壤生物活性下降的重要原因.  相似文献   

18.
用太阳黑子和自相关因子预测杉木生长   总被引:4,自引:0,他引:4  
以太阳黑子和自相关因子为预测因子,采用逐步回归分析方法,建立杉木〔Cunninghamialanceolata(Lamb.)Hook.〕胸径生长的预测模型,结果表明前3年和8年的太阳黑子相对数及前5年杉木胸径生长的年轮指数值对杉木胸径生长存在正相关,前1年和4年的太阳黑子相对数及前6年和7年杉木胸径生长的年轮指数值对杉木胸径生长存在负相关,该模型的模拟精度和预测精度分别为9895%和9845%,且可提前5年进行预测,为林木生长预测提供了新的系统分析方法  相似文献   

19.
A highly potent attachment-inhibitor, polygodial, was isolated from a hexane extract of the leaves of Tasmannia lanceolata. The attachment-inhibiting activity of polygodial against the blue mussel was increased 4-fold when used in combination with sorbic acid, anethole, and indole.  相似文献   

20.
杉木拟赤杨混交林林分生产力及生态效应研究   总被引:7,自引:0,他引:7       下载免费PDF全文
 本文从林分结构、生物量、群落特征、生产力、培肥土壤、涵养水源及林内小气候等方面对不同混交模式的杉木拟赤杨混交林及其纯林进行的研究结果表明:杉木拟赤杨是具有较高生产力和协调种间关系能力的针阔混交树种。7年生3:1带状混交林蓄积量和生物量分别比杉木纯林提高7.24%和18.22%,同时混交林还表现出比杉木纯林更好的培肥土壤、涵养水源、改善林内小气候等生态功能。应用AHP法进行不同混交模式的综合选择结果表明:3:1杉木拟赤杨带状混交模式是值得南方林区大力推广的杉阔混交模式。  相似文献   

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