生态公益林不同树种光适应特征研究

于广东省东莞市植物园3个不同郁闭度处理的生态公益林改造样地,观测了18个树种光合响应曲线与生长量指标.并通过模型拟合求得其最大光合速率(Am)、光补偿点(LCP)、光饱和点(LSP)以及表观量子产量(Φ)等光合参数以及它们之间的相关性,根据这些参数推断其喜光和耐荫性.最后将这些树种的光适应性归溪3大类:喜光类、喜光耐荫类和耐荫类.并根据这些树种的生长指标及其生物生态学特性,提出在进行生态公益林林分改造的树种选择时应注意的问题:一是根据不同林分选择相应的改造树种;二是依据群落动态演替规律进行树种配置.     

生态公益林改造树种在不同郁闭度林分中的光合作用与生长指标研究

在东莞市植物园3个不同郁闭度生态公益林改造试验样地中,观测了11个树种气体交换与生长量指标.结果表明:相似环境条件下,在郁闭度不同的造林林分中单叶净光合速率和气孔导度无显著差异,而蒸腾速率及水分利用效率则差异显著(P＜0.05),郁闭度越大,蒸腾速率越小,水分利用效率越高;不同郁闭度的造林方式对林分的树高、基径和树冠等生长量指标有显著影响(P＜0.05),郁闭度越大,生长量指标越小.不同树种的光合作用与生长量的数据拟合结果表明,光合速率与树种的生长量指标成显著正相关(P＜0.05).研究提示,在生态公益林的改造和营造过程中要注意两个问题:首先造林地选择和林分改造时疏伐的强度应充分注意林地的水湿条件对植物生长的影响;其次选择适宜光合能力的树种对林分改造的成败及其生态效果有重要影响.     

地被植物委蔓陵菜和东方草莓的耐荫性研究

选取两种地被植物为材料,对其耐荫性进行了定量和定性研究。结果表明蔓委陵菜在全光下、透光率50%、25%时的各项指标均表现良好,表明绢毛委陵菜对光的适应性广,是既耐荫又喜光性植物。东方草莓在全光下各项指标总体上均表现良好,与透光率50%、25%时的指标有差异,且差异较为显著。但是,从叶绿素含量、叶绿素a/b值、光饱和点及光补偿点等主要耐荫性生理指标上看,遮荫(50%)有利于其生长。表明东方草莓是喜光稍耐荫植物。     

紫茉莉光合生理特性及其影响因子研究

自然条件下利用Li-6400便携式光合测定系统测定紫茉莉（Mirabilis jalapa L.）的光合-光响应及CO2 响应数据;同时测定蒸腾速率（Tr）、气孔导度（Cond）、胞间CO2浓度（Ci）等光合参数,对生理因子和环境因子进行相关性分析.结果表明：由改进指数模型拟合得出紫茉莉的光合生理参数,其表明紫茉莉具有较强的耐荫性及净化空气的能力.相关性分析表明,环境因子中光合有效辐射（PAR）、大气CO2浓度及空气相对湿度（RH）和生理因子中胞间CO2浓度与气孔导度是影响紫茉莉光合作用的主要影响因子.因此,在栽培种植时,应采取遮阴或雾灌方式,提高光合作用效率.     

热带雨林蒲桃属三个树种的幼苗由遮荫转入强光后叶片的光抑制

以热带雨林蒲桃属(Syzygium)不同演替阶段的3个树种思茅蒲桃(早期)、乌墨(中期)和阔叶蒲桃(后期)作为材料,通过测定在自然光和两种遮荫条件下(14％和42％自然光)的光合能力(Pmax)和色素含量,以及两种遮荫条件下3个树种移至全自然光下处理1d,研究它们叶片叶绿素荧光参数的日变化．结果表明,全光下思茅蒲桃和乌墨幼苗的P一比遮荫条件下的显著提高,阔叶蒲桃幼苗的光合能力却显著降低,并显著低于其它2个树种。全光下3个树种的Car含量和Car／Chl均高于生长在遮荫条件下同种植物,不同光强下阔叶蒲桃的Car／Chl高于乌墨和思茅蒲桃。一天中,全光下3个树种的凡一直上升,Fv／Fm下降,但在傍晚能够恢复到清晨的值,表明全光下3个树种通过PSI反应中心的可逆失活有效地防御了光破坏．而遮荫的3个树种转入全光后,Fo一直上升,Fv／Fm下降程度较大,在傍晚仍不能恢复,表明发生了光合机构的光破坏．虽然阔叶蒲桃的Car／Chl高于乌墨和思茅蒲桃,由遮荫转入强光后NPQ也上升较快,但其光合能力较低,一天中热耗散能力的增强仍不能有效消耗过剩的光能,导致对强光敏感,光抑制程度较乌墨和思茅蒲桃重,这与其耐荫性和演替状态是一致的。     

改造强度对更新树种树高、地径生长的影响研究

对两年生两向分组试验的调查结果表明,马尾松生态公益林不同的改造强度对更新树种产生不同程度的影响,改造强度对更新树种的地径、树高的影响不大,但对树种间的以及树种与改造强度的交互作用的影响均达到极显著水平,两两间大多呈显著差异,光皮桦30米宽、虎皮楠10米宽、火力楠10米宽的改造强度的配置取得较大成功,可以参考运用推广.     

巨尾桉与黧蒴栲、红锥光响应曲线的比较研究

【目的】通过对广西桂林灵田乡巨尾桉（Eucalyptus grandis×E．urophylla）、黧蒴栲（Castanopsis fiSSa）和红锥（Castanopsis hystrix）光合一光响应曲线研究,寻找高光效阔叶树种。【方法】采用Li-6400便携式光合仪测定各树种光响应曲线。【结果】当光合有效辐射（PAR）开始增强时,各树种问净光合速率（Pn）差异较小,但随着光合有效辐射强度的增加,不同树种问净光合速率出现较大的差异。各树种的净光合速率随着光合有效辐射升高达到最高点之后稳定。蒸腾速率（Tr）、气孔导度（Gs）、水分利用效率（WUE）和CO2利用效率（CuE）对光合有效辐射的响应趋势与净光合速率相似,胞问CO：浓度、光能利用效率对光合有效辐射的相应趋势则与净光合速率相反。3个树种的净光合速率为3．975～20．800／μmol·m^2·s^1,巨尾桉最高,黧蒴栲最低。光补偿点和光饱和点都是巨尾桉最高,黧蒴栲最低。【结论】综合各指标和光响应变化规律,确定巨尾桉为优良的高光效阔叶树种,可在水分和光照条件好的地方适当推广。     

国槐、洋槐和香花槐的引种栽培技术总结

国槐、洋槐和香花槐同属于蝶形花科落叶乔木.洋槐为强阳性树种,喜光不耐庇荫,耐干旱瘠薄土壤,不耐水湿,耐烟尘.栽植时就要根据其习性选择适宜的土层和土质.     

AT试剂在茶树上的应用研究

茶树原产我国西南亚热带湿润季风气候区划,在系统发育过程中,逐渐形成耐荫、喜湿的生态特性,在个体发育中表现明显。茶树又是C_3植物,具有高光呼吸低光合速率的特性,且在丘陵地区的高温、强光和干旱影响下表现尤为突出,是限制丘陵茶产量与品质提高的生理因素。     

雌雄异株树种山杨、水曲柳和东北红豆杉光合特性对比

【目的】探究雌雄异株树种的光合生理生态特性,为正确评价其对环境的适应机制以及确定影响种群建成的因素提供理论参考。【方法】以野外成树为研究对象,通过Li-6400XT便携式光合作用测定仪对比分析了山杨(Populus davidiana)、水曲柳(Fraxinus mandshurica)和东北红豆杉(Taxus cuspidata)雌雄株叶片气体交换参数。【结果】3个树种整体上雌株光合特性优于雄株,雌雄株参数仅在山杨光补偿点(P_LCP)和最大羧化速率(C_E,max),水曲柳水分利用效率(E_WUE),东北红豆杉光饱和点(P_LSP)、光补偿点、羧化效率(C_E)和光呼吸速率(R_p)之间差异显著(P<0.05)。另外,雌株的叶性状指标并不低于雄株的。【结论】3个树种雌株较优的光合特性可能存在获取资源的补偿机制,以同时满足营养生长和生殖生长的生存需求。     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

A computer generator for randomly layered structures

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

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

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。     

Exciton Seebeck in Molecular Systems

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     

Achieving Unusual States of Matter Under High Pressure

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     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

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.     

An improved R-tree based on childnode''s probability

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).     

Integrating GIS Web services based on mediating architecture

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.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

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.