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1.
本文研究了滇西北油麦吊云杉林的净第一性生产力。林龄大,净第一性生产力也大。林龄约50年和150年林分的净第一性生产力分别为5.0315t/hm ̄2·a和13.7560t/hm ̄2.a;油麦吊云杉净第一性生产力占群落净第一性生产力的92.03%和65.39%;木材的净第一性生产力为1.3431和4.1417t/hm ̄2·a,仅占群落净第一性生产力的26.69%和30.10%。  相似文献   

2.
滇西北高山松林生物量的初步研究   总被引:8,自引:0,他引:8  
本文研究了滇西北高山松林的生物量。林龄大生物量减小。林龄约40年和100年的林分,生物量分别为294.306t/hm ̄2和231.495t/hm ̄2;在各器官中,树干生物量(143.532t/hm ̄2和102.120t/hm ̄2)最大,占群落总生物量的48.90%和44.24%;乔木一层(亦即高山松)的生物量254.283t/hm ̄2和171.408t/hm ̄2,占群落总生物量的86.41%和74.04%;与林龄约40年的林分相比较,林龄约100年的高山松林中,高山松生物量所占比例减小而黄背栎等树种的生物量增大。  相似文献   

3.
滇西北高山松林净第一性生产力的初步研究   总被引:3,自引:0,他引:3  
本文研究了滇西北高山松林的净第一性生产力。林龄大净第一性生产力小。林龄约40年的林分,净第一性生产力12.192t/hm ̄2·a,林龄约100年者为10.013t/hm ̄2·a;高山松净第一性生产力为9.849和5.621t/hm ̄2·a,占群落净第一性生产力的80.849%和56.14%;随着林龄增加,高山松的净策一性生产力及其在群落中所占的比例也逐渐减少,而其它树种的有所增加;在各器官中,叶的净第一性生产力最高,占34%~37%,其次为树干木材,占21.62%~27.44%。  相似文献   

4.
本文研究了云南中甸县吉迪村长苞冷杉群落的生物量和净生产量。结果为:长苞冷杉群落的生物量为351.623t/hm ̄2,其中乔木层占97.87%,灌木层占0.14%,草本层占0.17%,苔藓层占0.67%,凋落物占1.15%。群落的净生产量为1230.6g/m ̄2·a,其中乔木层占94.62%,灌木层占0.70%,草本层占1.63%,苔藓层占3.05%,优势种长苞冷杉的生物量和净生产量分别为334.777t/hm ̄2和1097.8g/m ̄2·a,分别占群落总量的95.21%和89.21%。其它乔木材种的生物量和净生产量分别为9.364t/hm ̄2和66.6g/m ̄2·a,分别占群落总量的2.66%和5.41%。  相似文献   

5.
元江栲群落的生物量研究   总被引:6,自引:0,他引:6  
本文研究了滇中半湿润常绿阔叶林元江栲群落的生物量。群落的总生物量为269.729t/hm ̄2,其中树干占54.69%,枝占16.68%,叶占2.92%,根占22.40%,凋落物占3.31%。群落的活生物量为260.811/hm ̄2,其中优势种元江栲占65.43%,其它栎类占18.10%,其它常绿树占9.32%,落叶树占6.75%,灌木种占0.21%,草本植物占0.02%。  相似文献   

6.
黄毛青冈群落的生物量研究   总被引:10,自引:0,他引:10  
黄毛青冈群落是滇中半湿润常绿阔叶林的另一个群落类型。群落的总生物量为135,909t/hm ̄2,其中树干占48.36%,枝占15.44%,叶占4.51%,根占27.76%,凋落量占3.93%群落的活生物童为130.569t/hm ̄2,优势种黄毛青冈占53.95%,其它栎类占16.58%,其它常绿阔叶树占1828%,落叶树占7,15%,灌木占3.88%,草本植物占0.16%。  相似文献   

7.
滹沱河湿地狭叶香蒲群落生物量研究   总被引:8,自引:2,他引:6  
研究了山西滹沱河湿地狭叶香蒲群落的结构和生物量,结果表明狭叶香蒲群落的总生物量为7076kg/hm^2,其中地上部分(叶、茎等)为2589.8kg/hm^2,地下部分(根)为4486.2kg/hm^2。建群种狭叶香蒲的生物量为5513.5kg/hm^2,其中地上部分(叶、茎等)为1725.6kg/hm^2,地下部分(根)为3805.9kg/hm^2,占群落总生物量的77.92%。优势种披针苔草和狼  相似文献   

8.
福建柏人工林生态系统生产力的研究   总被引:2,自引:2,他引:2  
以双重抽样法和“相对变比生长”模型(y=ax^be^cx)、“树形管道”模型(y=ax^bL^c)测定4个福建柏人工林的生物量。结果表明:24年生福建柏人工林密林分(Ⅱ类立地,2700株/hm^2)和26年生稀林分(I类立地,1216株/hm^2)的生物量,前者为178.240t/hm^2(乔木层占99.6%),后者为155.204t/hm^2(乔木层占99.6%);前者年平均净生产量为7.628  相似文献   

9.
结果表明:26龄杉木纯林群落生物量平均为183.89t/hm2,其组成层次的生物量分配序列(%)为乔木层(93.60)>枯枝落叶层(6.14)>灌草层(0.26)。乔木层年平均净生产量为6.62t/hm2·a,低于中心产区;平均木单株年平均净生产量10.93kg/a,高于中心产区,揭示现有林分密度偏小。26年生林分平均树高和平均胸径分别为20.7m和24.0cm,其干材生物量平均达61.5%,适宜培育杉木大径材。  相似文献   

10.
厦门东屿白骨壤群落生物量和能量   总被引:7,自引:0,他引:7  
讨论了厦门岛西海域海沧镇东屿的白骨壤群落的生物量和热值、群落各组分的能量分布状况。结果表明:该群落为单种组成的群落,其生物量现存量为4346.09g/m ̄2,各组分分配比是:侧根最多,占36.02%;多年生枝次之,占21.46%;幼枝较少,为0.33%;幼苗根最少,仅占0.11%。群落各组分干重热值相差较大,其中叶最高18.27kJ/g;主根居次,为17.85kJ/g。幼枝较低,16.11kJ/g;幼苗根最低为13.90kJ/g.群落的能量现存量为70553kJ/m ̄2,其中地上部占47.54%,地下部占52.46%。  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.
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   

15.
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   

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

19.
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   

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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