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1.
报道了中国红树植物1个新记录种——拉氏红树(Rhizophora×lamarckii),隶属红树科红树属,并介绍了其分布情况、生境特点和形态特征.此外,比较了中国产红树属植物分类性状的异同,对中国红树属植物种类和分布信息进行了补充.  相似文献   

2.
真红树和半红树植物体内盐分分布的比较研究   总被引:1,自引:0,他引:1  
研究了典型的真红树植物(红树Rhizophora apiculata、木榄Bruguiera gymnorhiza、海桑Sonneratia caeseolaris、桐花树Aegiceras corniculatum、白骨壤Avicennia marina)、半红树植物(黄槿Hibiscus tiliaceus、水黄皮Pongamia pinnata)和目前还存在争议的物种银叶树(Heritiera littoralis)体内各器官的K、Na、Cl元素分布特征.结果表明:(1)真红树植物和半红树植物体内盐分分布存在明显的区别,真红树植物体内各器官的Na、Cl含量明显比半红树高,叶片的K/Na值比半红树低;(2)真红树植物(除红树和木榄)和半红树植物的K:Na离子吸收选择性(USR)没有差异,但半红树植物的K:Na离子运输选择性(TSR)明显比真红树高;(3)真红树植物根系Cl含量随径级增加有先上升后下降趋势,与半红树植物不同.从盐分分布特征来看,银叶树最好归为半红树植物.  相似文献   

3.
海南岛的红树群落   总被引:7,自引:0,他引:7  
本文主要讨论海南岛的红树植物的种类及其分布,红树群落类型及其分布规律性。据我们调查:海南岛红树植物计有15科19属29种,占全国红树种数的94%,主要分布在东海岸,尤以琼东北最为丰富,如清澜港多达26种,按建群种划分计有12个类型,以红海榄林分布最广。群落类型的生态系列分布是有规律性,但也看到了有些类型因地形、基质特点有其分布的机缘性。  相似文献   

4.
1985年开始,林鹏院士及其研究团队开始从红树植物起源和分布的角度,探讨我国红树植物的耐寒性和向海性等级系列;并与红树林造林的宜林地选择相结合,从适应机制到造林实践深入研究红树植物生理生态学.这一系列成果均为红树林全球变化研究提供了基础信息,在我国乃至国际红树林全球变化研究领域都是很有价值的.综述了林鹏院士及其研究团队三十多年来在耐寒性等级系列对气候变暖和极端气候的响应,向海性等级系列对海平面上升的适应性,以及宜林地选择三方面的研究进展.  相似文献   

5.
重金属污染对红树植物影响的研究综述与展望   总被引:1,自引:0,他引:1  
红树林是热带、亚热带潮间带的优势植物群落,对环境重金属污染具有较高的耐受能力.该文从重金属的分布特点及红树植物生长与形态结构以及生理代谢等方面简要综述重金属污染对红树植物的影响研究,并在分子研究水平对该方向的研究提出展望.  相似文献   

6.
探讨了显胎生红树植物木榄(Bruguiera gymnorrihiza)、秋茄(Kandelia obovata)、隐胎生红树植物白骨壤(Avicennia marina)、桐花树(Aegiceras corniculatum)和非胎生红树植物木果楝(Xylocarpus grantum)的繁殖器官发育过程中铁(Fe)、钼(Mo)、锌(Zn)元素的含量变化.结果表明:在花蕾期,除白骨壤外,其他种类Fe元素含量相近,在0.035 2~0.045 4 μg/mg之间.隐胎生红树植物白骨壤、桐花树中Fe元素含量在种子期最高,分别为0.090 2和0.073 3 μg/mg,萌发后呈现降低的趋势,在胚轴成熟期达到最低.在种子期,Mo元素含量在胎生红树植物中差异不大,在0.288 2~0.302 0 ng/mg之间,平均为0.294 5 ng/mg,明显高于非胎生红树植物木果楝0.105 6 ng/mg.种子萌发后,胎生红树植物中Mo元素含量下降.在同一时期,胎生红树植物种子的Mo元素含量明显大于木果楝.在木果楝的繁殖器官发育过程中,Zn元素含量逐渐下降,且比同期的胎生红树植物低.  相似文献   

7.
红树林生境具有高盐、水淹低氧等特征,红树植物对高盐、水淹生境的适应性决定了其可以成功定植并占据相应的潮间带.红树植物可以通过各种机制耐受、抵抗或避免高盐、水淹,在海岸潮间带下生存.在生理及分子水平综述了红树植物适应水淹和高盐生境的研究进展,揭示了其独特的调控模式,为进一步研究其适应性机制提供了基础.  相似文献   

8.
中国海岸红树植物区系研究   总被引:24,自引:3,他引:21  
我国海岸红树植物共有30种,隶属于20属16科,其中除了7种嗜热窄布种和3种抗低温广布种之外,其它均为嗜热广布种。从台湾高雄以南至海南岛东南端一线是嗜热窄布种的自然分布北界;厦门以北至福鼎海岸是以抗低温广布种占优势,其自然分布北界是在福建的福鼎海岸,反映了泛热带区系性质显著减弱;其它海岸以嗜热广布种占优势,表现出亚热带区系性质。从红树植物区系特点来看,我国的红树植物与菲律宾、巴布亚-新几内亚、澳大利亚北部更为密切,这种联系似与红树植物的起源与传播有着密切关系。  相似文献   

9.
应用地统计学方法,结合青海省嵩草草甸地上净生产量及环境因子的相关数据,从空间自相关关系以及变异函数入手,对其空间分布特征进行了分析和讨论.结果表明,青海省嵩草草甸地上净生产量的空间分布呈明显的带状异向性,空间分布的变化与所研究的尺度和方向紧密联系.对环境因素的分析表明,该区年降水量的空间分布特征与嵩草草甸地上净生产量的分布在各向同性(isotropic, ISO)以及2个主要方向上的各向异性的变化均相一致.因此,在开发和利用嵩草草甸这一牧场资源时,应考虑其空间分布特点.  相似文献   

10.
新疆阜康土壤微量元素的空间变异分析   总被引:1,自引:0,他引:1  
运用地统计方法,研究了新疆阜康地区土壤表层微量元素的空间异质性特征.结果表明:4种微量元素的空间异质性主要是结构性因子和随机因子共同作用的结果.土壤微量元素的变异函数均可很好地拟合成高斯模型,块金值和基台值之比均为25%~75%,为中等强度的空间相关性.研究区土壤微量元素质量分数空间变异具有各向异性特征,表现为二阶趋势效应.Moran's I系数分析表明4种微量元素均呈现一定强度的空间自相关关系.土壤微量元素质量分数的等值线图分析表明,不论在什么方向上,土壤微量元素质量分数呈现一定规律分布.  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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