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1.
恶性杂草 微甘菊   总被引:1,自引:0,他引:1  
微甘菊是菊科假泽兰属植物(Mikania spp.)的通称(俗称)。该属植物约有250种,主要分布于热带美洲,少数分布于南非和热带亚洲。1949年印度尼西亚的ROGAR植物园将其中的一种(M.micrantha)从巴拉圭引入,1956年开始用于橡胶园地面的覆盖,从而在印尼传播开来。目前已侵入毛里求斯、印度、斯里兰卡、孟加拉、菲律宾、泰国、文莱、马来西亚、新加坡、巴布亚新几内亚、澳洲及我国的香港和深圳。微甘菊在其原产地属于一般植物,不成为有害杂草,甚至在南美洲一些地区,还将其作为药用植物,用来防治癌症、霍乱、疟疾、流感、蛇咬伤等。但是微甘菊在侵入东南亚地区以后却暴发蔓延,成为严重的恶性杂草。近年来发现微甘菊(种类待订)已侵入我国广东深圳  相似文献   

2.
研究了华南地区外来入侵种薇甘菊Mikania micrantha H.B.Kunth和它的本地同属种假泽兰Mikaniacordata(Burm.f.)B.L.Robinson的叶构建特性因子构建成本(Construction Cost,CC)、叶N含量以及叶面积干质量(Specific leaf area,SLA)。两个种的叶性因子表现出以下的形式:本地种假泽兰的构建成本(CC)和单位叶面积的氮含量比外来种薇甘菊更高,比叶面(SLA)以及单位干质量的叶氮含量显著低于后者。无疑,低CC显示其低能耗及高资源利用率,这也可能是其快速生长并广泛传播的主要机理,因此,植物叶构建成本也可能是评价其入侵潜力的重要因子。  相似文献   

3.
薇甘菊的生物学特性、危害及其防控   总被引:1,自引:0,他引:1  
薇甘菊是世界上十大恶性藤本杂草之一,2000年前后从缅甸传入云南省德宏州后,迅速在周边州市传播蔓延,2005年登陆保山,2008年11月,临沧市境风首次发现薇甘菊。薇甘菊所到之处,对当地林业、农业造成了巨大损失,破坏生态平衡和生物多样性。本文主要通过阐述薇甘菊的生物学特性及其危害,综合国内研究和应用成果,介绍薇甘菊的防治措施。  相似文献   

4.
薇甘菊及其防除技术   总被引:2,自引:0,他引:2  
薇甘菊是我国新入侵的、危害性极强的农林害草,在我国香港、台湾、广东等地广泛分布并产生严重危害。总结我国多年来的研究成果,系统介绍薇甘菊的生物特性、危害特征及防除技术。  相似文献   

5.
刘华杰 《科技潮》2009,(4):46-46
菊科是一个大“科”,成员众多。生态入侵植物中菊科闹得挺凶,我听说过的就有紫茎泽兰、一枝黄花、三裂叶豚草、薇甘菊、黄顶菊、假臭草、豚草、飞机草、假苍耳等。  相似文献   

6.
在香港郊野公园内选择薇甘菊危害较严重的草灌丛、灌木林和常绿阔叶林3种群落类型,设置样地5 000 m2,用0.05~0.1 g#8226;m-2嘧磺隆对样地中的薇甘菊进行化学防除试验, 并在施用除草剂后3、5和14个月跟踪调查施药对薇甘菊的杀灭效果以及对样地中其他植物和群落物种多样性的影响.结果表明嘧磺隆对样地薇甘菊有极好的杀灭效果.施药后3个月,样地中有45种植物产生了不同程度上的影响,占样地内所有种类的30%.受影响最大的是藤本和草本植物,其次是灌木,乔木受影响最小.施药后14个月,乔木和灌木生长正常, 草本植物基本恢复.施药清除薇甘菊后,能大幅度地增加群落的物种多样性.  相似文献   

7.
近来,一种俗称微甘菊的外来杂草侵入广东,由于它破坏力极强,引起科学界及电视、报纸、电台等媒体密切关注。中国科学院华南植物研究所的专家说,我国现有两种微甘菊,一种是我国原来就有的,另一种原产于南美洲,近来传入我国,它们的学名都叫假泽兰。我国原产的微甘菊是无害的。而另一种原产于南美洲、后被引入印尼植物园用于橡胶园的地面覆盖,在那里传播开来,很快侵入印度、斯里兰卡、泰国、马来西亚、澳洲、香港等地。据马来西亚报道:  相似文献   

8.
 外来植物薇甘菊(Mikania micrantha HBK.)已入侵华南许多地区,并造成严重危害。探讨了外来植物薇甘菊凋落物对4种本地植物大叶榕(Ficus virens)、潺槁树(Litsea glutinosa)、樟树(Cinnamomum camphora)和台湾相思(Acacia confusa)凋落物分解的影响。凋落物分解采用网袋法,将薇甘菊凋落物分别与本地植物凋落物按3个比例混合,3个比例为,m(薇甘菊)∶m(本地植物) = M1(1∶4),M2(1∶1)和M3(4∶1)。分解60 d后,测定凋落物的分解速率与养分释放。结果表明,薇甘菊与本地植物凋落物混合比例为M1时,凋落物分解速率变慢,但在M3时,凋落物的分解速率变快。与单独本地凋落物养分释放相比,薇甘菊凋落物混入后C释放有所下降,而N素释放量有所提高,这种N释放量的增加可能会对薇甘菊的入侵产生正反馈作用。  相似文献   

9.
《广西科学》2009,(4):388-388
世界十大有害草本植物(紫茎泽兰,薇甘菊,空心莲子草,豚草,毒麦,互花米草,飞机草,水葫芦,假高梁,布袋莲)之一的水葫芦(凤眼莲)在中国南方19个省市的广大水域随处可见。其生长繁殖十分迅速,在适宜条件下每天可增加20%~30%的生物量,8个月内就能从10棵增至60万棵,造成破坏生态、堵塞河道、影响航运、  相似文献   

10.
田野菟丝子控制薇甘菊的生态评价   总被引:12,自引:0,他引:12  
通过对广东省东莞、深圳、汕尾、香港等地的 11个田野菟丝子CuscutacampestrisYuncker控制薇甘菊危害的野外样地的调查研究 ,结果表明 :田野菟丝子能寄生并致死薇甘菊 ,使样地群落中薇甘菊的盖度由 75 %~95 %降低到 18%~ 2 5 % ,较好地控制住薇甘菊的危害 ,并使受害群落的物种多样性明显增加 ,而不会致死样地内其它植物 ,虽能在 83种植物 (占样地植物的 74 1% )上寄生生长 ,但对其中的乔木、灌木、藤本及草本植物无明显影响 ,它们的长势正常 ;仅有包括 8种菊科植物在内的 15种草本植物 (其中 12种为外来有害杂草 )会受到田野菟丝子一定程度的影响 ,因此 ,初步认为田野菟丝子控制薇甘菊危害的方法基本上是可行的、安全的。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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