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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 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.
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   

20.
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   

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