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1.
季风常绿阔叶林短刺栲群落的生物量研究   总被引:28,自引:0,他引:28  
本文采用维量分析以估测滇西南季风常绿阔叶林短刺栲群落的生物量,并且较详细地分析了短刺栲群落活生物量的径级对市、层次分布、器官分布和种类分布.12年生的幼龄林总生物量为92.875t/hm~2,其中树干占47.57%,枝占17.17%,叶占7.53%,根占22.29%,草食动物采食量占0.61%,凋落量占4.82% 42年生的中龄林总生物量为166.956t/hm~2,其中树干占53.54%,枝占20.59%,叶占4.13%,根占18.83%,草食动物采食量占0.44%,凋落量占2.71%.  相似文献   

2.
云南普洱地区思茅松林的净第一性生产力   总被引:2,自引:0,他引:2  
本文研究了普洱县小黑江地区海拔890~920 m的思茅松林的净第一性生产力.结果如下:①林分净第一性生产力随林龄增加而减少.12年生和23年生林分净第一性生产力分别为26.9603 t/hm~2·a和23.9554 t/hm~a.②林分净第一性生产力的层次分配顺序为:乔木层>灌木层>草本层.③林分净第一性生产力在器官间的分配顺序为:树干>枝、叶>根系>根劲>果实.④89%~90%的林分净第一性生产力集中分配在思茅松中. ⑤用重量比值法求算出12年生和23年生思茅松林分叶被采食量分别为0.8227 t/hm~2·a和1.3578 t/hm~2·a.  相似文献   

3.
本文研究了滇中半湿润常绿阔叶林元江栲群落的净第一性生产量,其净生产量为1950.0g/m ̄2·a,其中树干占33.09%,枝占25.47%,叶占21.42%,根占18.60%,叶被采食量占1.42%。优势种元江栲的净生产量占群落净生产量的61.91%,其它栎类占17.21%,其它常绿阔叶树占110.24%,落叶树占8.78%,灌木占0.75%,草本植物占0.13%。  相似文献   

4.
本文研究了滇中地区半湿润常绿阔叶林黄青冈群落的净第一性生产量,其净生产量为1411.7g/m ̄2·a,其中t树干占40.09%,枝占20.02%,叶占20.18%,根占18.61%,叶被采食量占1.10%。优势种黄毛青冈占49.20%,其它栎类占13.15%,其它常绿树占24.83%,落叶树占8.62%,灌木和草本植物各占3.58%和0.61%。  相似文献   

5.
海莲红树林的生物量和生产力   总被引:11,自引:1,他引:11  
本文是海南东寨港红树林研究的一部分。主要讨论55龄海莲群落的生物量和生产力。测定结果表明:海莲群落的植物生物量为 42.03kg/m~2,其中地上部为24.85 kg/m~2,地下部为 17.18kg/m~2,地下部占总量的40.9%。1983年初级净生产量为2.95kg/m~2·a,其中叶等年凋落物为 1.31 kg/m~2·a,占总量的44.4%。大量的凋落物有利海湾河口水产渔业的发展。  相似文献   

6.
云南昌宁县思茅松林的生物量和净第一性生产力   总被引:5,自引:0,他引:5  
本文研究了昌宁县西桂林场海拔1420~1710 m思茅松林的生物量和净第一性生产力.结果如下:①随着林龄增加,生物量增加而净第一性生产力减少.13年生林分的生物量为102.2936 t/ hm~2、净第一性生产力为24.5636t/hm~2·a, 35年生林分的生物量为218.5430t/hm~2、净第一性生产力为18.3600t/hm~2·a. ②活生物量及净第一性生产力的层次分配顺序为:乔木层>灌木层>草本层.③净第一性生产力在器官间的分配顺序为:树干>叶>根、根系>根颈.13年生和35年生林分生物量在器官间的分配顺序分别为:树干>枝>叶>根系>根颈;树干>根系>根颈>枝>叶.比较发现,思茅松林分布区西北部林分的生物量和净第一性生产力比中部林分的低.  相似文献   

7.
广西红海榄群落的生物量和生产力   总被引:10,自引:4,他引:10  
讨论了广西合浦县山口英罗湾70年生的红海榄群落的生物量和生产力,测定结果表明,红海榄群落的生物量为29158.0g/m~2,其中地上部为19621.2g/m~2,地下部为9536.8g/m~2,支柱根的生物量占群落总生物量的25.28%,是红海榄极为重要的组成部分,也是红海榄不同于其他植物的特点,该群落1989年的净初级生产量为1537.1g/m~2,其中年凋落物量为631.3g/m~2。  相似文献   

8.
本文主要讨论武夷山黄山松群落的钾、钠累积和循环。测定结果表明:(1)群落现存量中钾、钠的库量分别为35.876g/m~2和2.637g/m~2,其中地上部分为19.944g/m~2(占总库量的55.59%)和1.817g/m~2(占68.90%);地下部分别为15.932g/m~2(占44.41%)和0.820g/m~2(占31.10%);(2)在钾、钠的生物循环中,年吸收量分别为2.230g/m~2·a和0.136g/m~2·a;年存留量分别为2.230g/m~2·a和0.036g/m~2·a;(3)钾的周转期55年,钠的周转期75年,钾的周转比钠快;(4)钾的富集率为1.160,说明该群落中林木仍在对钾吸收累积;而钠的富集率为0.929,说明了在该群落中林木对钠不再累积。  相似文献   

9.
采用连续钻取土芯法对苏北两种模式(网格模式PW、网格台田模式PT)下4年生杨树(Populus deltoides cv. 35.)人工林细根(≤5 mm)进行研究,并采用不同估算方法对细根年净生产量、死亡量、分解量和周转率进行比较。结果表明,细根现存生物量为1.26~1.86 t/hm2。PW和PT两种模式下,细根年净生产量、死亡量、分解量和周转率分别为2.24 t/hm2、2.34 t/hm2、1.88 t/hm2、1.43次/a和1.43 t/hm2、1.29 t/hm2、1.37 t/hm2、1.31次/a,与决策矩阵法相比,采用最大最小值法平均低估了19%的细根年净生产量、68%的年死亡量、89%的年分解量和23%的周转率;土壤养分和季节水分动态是PW和PT模式细根生产量和周转率存在差异的主要原因。  相似文献   

10.
广西红海榄红树群落的能量研究   总被引:14,自引:1,他引:14  
本文主要研究广西山口英罗湾红海榄植物各组分的热值、落叶热值月变化、群落能量现存量及群落年能量固定量,结果表明:红海榄植物各组分热值之间有一定差异,波动范围为17.28~18.67kJ/g,落叶热值10月份高达18.19kJ/g,2月份低至17.30kJ/g,与鲜叶相比,落叶热值的波动较小,红海榄群落的能量现存量为5.20×10~5kJ/m~2;无过凋落物带走的能量年总量为1.12×10~4kJ/m~2;该群落的年能量固定量为2.73×10~4kJ/m~2,其中群落年净增长的能量(存留量)为1.61×10~4kJ/m~2占总固定量的58.9%,而能量固定量中其余部分占41.1%,以凋落物的形式向环境输送,这些能量是海湾河口生态系统中其它生物赖以生存和发展的重要能量基础。  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 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   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
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   

15.
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   

16.
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   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
19.
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   

20.
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   

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