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1.
秦岭大熊猫主食竹的分类学研究(Ⅱ)   总被引:5,自引:0,他引:5  
目的为理清秦岭地区大熊猫最集中分布的陕西佛坪国家级自然保护区及陕西周至县老县城自然保护区大熊猫主食竹的种类和分布区域。方法采用常规的植物分类学研究方法,通过大量的野外调查、室内标本鉴定、查阅有关标本室的标本及文献资料考证,对所采集的标本进行分类学研究。结果这两个保护区内共有野生禾本科竹亚科植物3属、5种,其中巴山木竹Bashaniafargesii和秦岭箭竹Fargesia q inlingensis为该区域内分布面积最大的竹种。结论在这两个保护区内,巴山木竹和秦岭箭竹是大熊猫最主要的主食竹种,龙头竹Fargesia dracocephala和华西箭竹Fargesia nitida次之。为进一步研究大熊猫主食竹种提供了基本的资料依据。  相似文献   

2.
2005年以来,四川、陕西部分地区出现了冷箭竹、刺竹等大熊猫主食竹大面积开花枯死的现象,对野生大熊猫构成了成胁。  相似文献   

3.
为了抢救大熊猫,解决近期匮食危机,建立长期的食料基地及稳定的主食竹类生态系统,根据国务院、林业部指示,林业部科技司下达了“大熊猫主食竹类生态系统研究”项目,并确定由四川省林业科学研究所主持此项研究。为落实这一研究项目的研究方案,林业部科技司和保护司于一九八四年六月二十四日至二十九日在成都召开了“大熊猫主食竹类生态系统研究”论证会。参加会议的有林业部科技司和四川省林业厅的领  相似文献   

4.
讨论了卧龙自然保护区大熊猫栖息地主食竹开花对大熊猫的影响,建立了具有偏食行为的大熊猫-冷箭竹-拐棍竹三维捕食食饵脉冲微分系统,证明了系统大熊猫灭绝周期解的局部和全局渐近稳定性,并进一步给出了系统持续生存的条件.结论表明,在一定的条件下,卧龙自然保护区大熊猫单一主食竹开花并不会影响大熊猫的生存.  相似文献   

5.
王冰洁  王建宏 《甘肃科技》2014,30(18):141-143
甘肃记录的大熊猫食用竹有5属13种、1变种、1变型,其中箭竹属7种,刚竹属3种1变种1变型,箬竹属1种、寒竹属1种、巴山木竹属1种.其中缺苞箭竹、华西箭竹、青川箭竹、龙头竹、糙花箭竹、团竹等6种竹子为大熊猫主食竹,大面积分布于文县、迭部县、舟曲县和武都区的大熊猫栖息地和潜在栖息地,是甘肃省大熊猫生存的物质基础.此外,紫耳箭竹、巴山箬竹、紫竹、毛金竹、斑竹、石绿竹、黄古竹、刺黑竹、巴山木竹为大熊猫偶食竹,零星分布于文县、武都相对低海拔的林缘及村庄附近.依据竹类营养器官的形态特征,本着简洁实用的原则编制了甘肃大熊猫食用竹分属、分种检索表,以便于甘肃大熊猫保护区一线从事保护、科研和监测的人员识别.  相似文献   

6.
科技事件     
竹子开花,大熊猫会不会再次断粮2005年以来,四川、陕西部分地区出现了冷箭竹、刺竹等大熊猫主食竹大面积开花枯死的现象,对野生大熊猫构成了威胁。  相似文献   

7.
《科技知识动漫》2008,(7):45-45
大熊猫为食肉类动物,但它们食物成分的99%却是高山深谷中生长的20多种竹类植物。随着季节变化,大熊猫食谱中的竹种和所食竹部位也有差异,它们最喜爱的是竹笋,竹笋幼嫩多汁,适口性好,易消化吸收,是大熊猫的美昧佳肴。  相似文献   

8.
为探讨巴山木竹地上部分生物量及其分配规律,以深入理解秦岭山系大熊猫对巴山木竹的觅食对策和环境承载力,于2008年11月到2009年4月通过设置样方对陕西佛坪自然保护区三官庙保护站管护范围内巴山木竹的生物量进行了调查.结果表明随着龄级增长,巴山木竹地上生物量呈增长趋势,各器官生物量所占比例大小依次为:茎>枝>叶.在海拔梯度上,以1600-1800m巴山木竹地上生物量最大.通过回归分析显示,巴山木竹竹叶生物量可以通过竹株基茎以幂函数进行较好地拟合.上述研究结果表明,为保护好研究区域内大熊猫的冬居地,应有效控制海拔1600-1800m落叶阔叶和针阔混交林中的人为活动.  相似文献   

9.
拐棍竹生物学特性的研究秦自生等四川师范学院珍稀动植物研究所竹子研究汇刊1993,12(1):6~17拐棍竹(Fargesiarobusta)是大熊猫的主食竹种之一,仅产于我国四川西部中山地带。作者在该竹种分布中心─—卧龙山自然保护区开展了对拐棍竹的生...  相似文献   

10.
对神农架白草坪作为大熊猫可居地的生态环境作了初步调查,结果表明,白草坪在地质、地貌、气候土壤、水源、植被、竹类及陆生脊椎动物等方面均与现存大熊猫栖息地类似,从而为向东扩展大熊猫栖居地提供了一份有力的依据。  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.
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   

13.
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   

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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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