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1.
2003-2005年,先后6次对湖南小溪国家级自然保护区境内的蝗虫进行了标本采集,共鉴定出44种,隶属于3总科8科34属.其区系成分以东洋界种类占绝对优势(65.90%),广布种也占一定的比例(29.55%),而古北界的种类很少(4.55%).这说明小溪国家级自然保护区的蝗虫区系具有明显的东洋界特征,但也体现了两界交汇混杂的过渡性质.造成这一区系特征的主要原因是该区具有特殊的历史地理条件.  相似文献   

2.
湖南省德夯风景区蕨类植物区系的研究   总被引:7,自引:0,他引:7       下载免费PDF全文
陈功锡  谷中村   《广西植物》1996,16(4):331-337
德夯风景区位于湖南省西北部吉首市之西。海拔189.4~964.6m,面积252km2。该区蕨类植物有28科,51属,118种,区系特点是:(1)种类丰富而密度大,以鳞毛蕨科,水龙骨科,蹄盖蕨科,卷柏属(Selaginella),铁角蕨属(Asplenium),凤尾蕨属(Pteris)等为优势类群,科内、属内种数贫乏;(2)属的地理成分以热带成分为主,温带与亚热带成分次之,无特有属。种的地理成分以亚热带成分为主,热带与温带成分次之,特有种类丰富;(3)东亚成分(尤其是中国—日本成分)众多。可能是东亚成分分布中心的一部分;(4)与天平山、佼母溪关系最密切,与庐山、黄山、大瑶山关系较密切,与神农架、鼎湖山较疏远。  相似文献   

3.
对湖南德夯风景区峡谷特殊生境植物区系和生态适应性进行了初步研究,调查统计结果表明:(1)该区共有维管束植物1 162种,隶属于148科566属.其中蕨类植物90种(21科,44属,占总数的7.7%)、裸子植物1种(1科,1属)、被子植物1 071种(126科,521属,占总数92.2%),有草本704种(占60.6%)、木本458种(占39.4%).(2)峡谷特殊生境区系是德夯植物区系的主体,体现了该区植物区系的特征与性质.有峡谷生境专性种160种,分别归属71科121属,其中蕨类植物36种( 15科,23属)、被子植物124种(单子叶植物11种,双子叶植物113种),草本植物102种(占63.7%)、灌木26种(占16.3%)、乔木21种(占13.1%)、藤本11种(占6.9%).(3)群落中灌木层和草本层的优势物种大部分为峡谷生境专性种,乔木层优势植物中专性种较少.(4)德夯峡谷特殊生境专性种在生长型、器官形态、生活史、生态适应类群及适应性分区等方面形成了一系列与环境相适应的特征以及特定的适应分布结构,随着群落演替的进行,峡谷生境专性植物由少逐步增多,演替后期则逐步减少.  相似文献   

4.
秦岭太白山北坡蝗虫的群落结构   总被引:7,自引:0,他引:7       下载免费PDF全文
在秦岭太白山北坡23个样地内采集到蝗虫2总科7科25属34种。应用数量分类、多样性指数及相似性分析方法对太白山北坡蝗虫群落垂直分布样方资料进行了分析。应用数量分类法可将蝗虫群落按植被类型分为8种,即农耕带、栓皮栎林带、锐齿栎林带、辽东栎林带、桦木林带、冷杉林带、落叶松林带、高山草饲带。太白山蝗虫群落垂直分布规律明显。其中高海拔(如高山草甸带)的蝗虫种类数和多样性明显低于中低海拔,中低海拔(锐齿栎林带)蝗虫种类和多样性指数最大。但低海拔的农耕带人为干扰大,植被较单一,蝗虫优势种的优势度大,蝗虫密度大,而种类数较少。  相似文献   

5.
湖南德夯风景区藤本植物多样性研究   总被引:2,自引:1,他引:1  
对德夯风景区藤本植物进行了调查,结果表明:本区有藤本植物249种(含变种),隶属于49科110属.科属的区系性质均以热带为主,分别占54.17%、60.91%.生活型以木质藤本为主,占68.67%.攀援类型分为4大类、9小类,其中缠绕类最多,占38.96%,卷曲类占27.31%,搭靠类占20.07%,吸固类最少,仅占13.66%.藤本植物按资源类型可分为药用植物、观赏植物、纤维植物、芳香植物、食用植物及其他,药用植物居多,而最具潜力的是观赏类植物.  相似文献   

6.
东北地区不同生境内蝗虫区系的比较   总被引:10,自引:4,他引:6  
经过多年的调查,并参考其他研究成果,在所设的8个样点中统计出蝗虫7科,39属,107种。分析了东北地区蝗虫的群落结构、各蝗种的区系地理成分、种属分配,并讨论了该区蝗虫的地理分布关系等。结果表明,东北地区的蝗虫古北种占绝对优势,约占总种类数的87.85%,在所调查的8种类型的生境中,长白山地区的蝗虫种类最为丰富,向海自然保护区的蝗虫种类最少,并且和其他各生境蝗虫组成的相似性指数均较低。  相似文献   

7.
宁夏黄河湿地现已知有44种蝗虫,隶属2总科8科24属,占全自治区蝗虫总种数的50.57%。湿地蝗虫在种类组成上以蝗总科中的斑翅蝗科为优势类群,共计12属15种,占总种数的34.09%。网翅蝗科次之,共计3属11种,占总种数的25%。区系成分分析结果表明,宁夏黄河湿地蝗虫完全为古北界区系成分。在中国地理区划中有17个区系型,以蒙新区特有种所占比例最高,计17种,占总种数的38.64%。其次为蒙新区—青藏区系型,计4种,占9.09%。以宁夏黄河湿地11个自然行政地理区划为分类单元,对其种类生态地理分布进行聚类分析,探讨了地理生态环境与生物物种多样性之间的关系。  相似文献   

8.
山西省8种蝗虫8个种群的遗传学研究   总被引:13,自引:2,他引:11  
采用水平淀粉凝胶电泳技术,对采自山西省蝗虫区系的优势种类;斑腿蝗科(Catantopidae),斑翅蝗科(Oe-dipodidae)和网翅蝗科(Arcypteridae)3科7属8种蝗虫的11种酶进行了检测,共辨析出17个酶基因座位,并计算出等位基因频率和遗传距离,等位基因频率分析表明:Ao-I、Est-3,G3pd-1、Idh-2和Mdh-2基因座位的等位基因少,等位基因数目在种间变化较小,故推断其进化速率较慢,利用这些基因座位的保守特征,可作为分子标记研究较高级阶元的系统发育关系,而Gpi-1,Ldh-1和Me-1基因座位的等位基因多,等位基因数目在种内和种间差异较大,可以用作种,属间及种群间遗传结构的比较研究。对每个基因座位的各基因型进行χ^2检验,除Acp-1,Adk-1,Ao-1和Ao-2在部分蝗虫中符合Hardy-Weinberg平衡外,其余绝大多数基因座位的基因型频率显著偏离H-W平衡。在所研究的8种蝗虫中,多态位点百分率普遍较高(P=64.7%~94.1%),但由于杂合子数目较少而使每个基因座位的平均杂合度降低(Ho=0.024~0.087),对多态位点百分率分析发现:迁飞能力是影响蝗虫种间遗传变异的因素之一,具有迁飞能力的蝗虫(P=88.2%~94.1%)较非迁飞性蝗虫(P=64.7%~94.1%)表现出较高的遗传多态性,但也有例外,如中华稻蝗(Oxya chinensis)的P值高达94.1%,上述结果表明:由于迁飞行为可使个体暴露于各种不同环境,故而种群保持较高的遗传多态性能增强该物种在不同栖息地的生存和繁殖能力,因此,迁飞有利于维持迁飞性蝗虫遗传多态性的动态平衡。根据Nei的遗传一致度(I)和Roger的遗传距离(D)进行分析,结果与基于形态特征确定的分类阶元系统关系基本相符;即同属的小翅雏蝗(Chorthippus fallax)和白纹雏蝗(Chorthippus albonemus)具有最高的遗传一致度(I=0.813)和最小的遗传距离(D=0.336),同位不同属间遗传一致度(I=0.798~0.559)和遗传距离(D=0.398~0.474)居中,科之间I值最小(I=0.523~0.479),D值最大(D=0.505~0.523),利用UPGMA对I值和D值进行聚类,所得两种聚类图在同属种间和同科属间的关系一致,但在科间关系有所差别,Roger的遗传距离(D)聚类树图表明:斑腿蝗科物种和斑翅蝗科物种间表现出较小的遗传距离(D=0.505),而网翅蝗科与以上两科的遗传距离也极为接近(D=0.523),综上所述,等位酶分析能较好地反映蝗虫同属种间和同科属间的亲缘关系,若能断更高阶元的系统发生,则需结合其他性状进行综合分析。  相似文献   

9.
该研究在对德夯风景名胜区种子植物进行多次野外调查及查阅相关资料文献的基础上,从科、属、种层面、不同特殊生境类型,并与邻近地区进行比较,综合分析探讨德夯的植物区系特征,深入揭示该区植物区系的性质和地位,为该区自然资源的保护和管理以及持续利用提供科学依据。结果表明:(1)德夯种子植物类群丰富,该区共有野生种子植物154科710属1 626种,分别占武陵山地区种子植物科、属、种总数的94.48%、83.43%、54.00%,分别占湖南省种子植物科、属、种总数的73.33%、54.20%、33.46%。(2)该区种子植物区系地理成分复杂,科含12个分布区类型,属含14个,种含15个,科和属的地理成分均以泛热带分布型所占比例最高,种的地理成分以中国特有分布型所占比例最高;特有现象明显,该区含7个东亚特有科、2个中国特有科,27个中国特有属,588个中国特有种,其中含39个华中特有种,29个武陵山地区特有种和6个德夯特有种。(3)该区植物区系成分随生境不同出现分化,台地、悬崖、谷地3种代表性生境区系成分差异明显,和邻近的壶瓶山、小溪、乌龙山3个地区具有较高的相似性。总体上,德夯风景名胜区植物区系具有东亚植物区系特征,在武陵山地区植物区系中具有重要地位。  相似文献   

10.
丁方美  黄原 《昆虫学报》2008,51(1):55-60
本文的目的是通过对斑翅蝗科部分种类的线粒体ND2基因进行分析,重建斑翅蝗科昆虫的系统发育关系,并探讨分子系统发育关系和传统分类结果的异同。扩增并测定了我国斑翅蝗科10属16种蝗虫的线粒体ND2全基因1 023 bp的序列,对序列的碱基组成、转换颠换、系统发育信号等进行了分析。并基于ND2全基因序列数据,分别采用邻接法(NJ)、最简约法(MP)、最大似然法(ML)和贝叶斯法重建了10属16种蝗虫的系统发育关系。结果表明:斑翅蝗科蝗虫ND2全基因A+T含量平均为74.6%;痂蝗亚科和异痂蝗亚科没能得到区分,建议合并为一个亚科;而斑翅蝗亚科和飞蝗亚科的分类地位还存在争议。  相似文献   

11.
The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.  相似文献   

12.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

13.
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.  相似文献   

14.
A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.  相似文献   

15.
The unitary conductances and permeability sequences of the rat connexin40 (rCx40) gap junction channels to seven monovalent cations and anions were studied in rCx40-transfected neuroblastoma 2A (N2A) cell pairs using the dual whole cell recording technique. Chloride salt cation substitutions (115 mM principal salt) resulted in the following junctional maximal single channel current-voltage relationship slope conductances (γj in pS): CsCl (153), RbCl (148), KCl (142), NaCl (115), LiCl (86), TMACl (71), TEACl (63). Reversible block of the rCx40 channel was observed with TBA. Potassium anion salt γj are: Kglutamate (160), Kacetate (160), Kaspartate (158), KNO3 (157), KF (148), KCl (142), and KBr (132). Ion selectivity was verified by measuring reversal potentials for current in rCx40 gap junction channels with asymmetric salt solutions in the two electrodes and using the Goldman-Hodgkin-Katz equation to calculate relative permeabilities. The permeabilities relative to Li+ are: Cs+ (1.38), Rb+ (1.32), K+ (1.31), Na+ (1.16), TMA+ (0.53), TEA+ (0.45), TBA+ (0.03), Cl (0.19), glutamate (0.04), and NO3− (0.14), assuming that the monovalent anions permeate the channel by forming ion pairs with permeant monovalent cations within the pore thereby causing proportionate decreases in the channel conductance. This hypothesis can account for why the predicted increasing conductances with increasing ion mobilities in an essentially aqueous channel were not observed for anions in the rCx40 channel. The rCx40 effective channel radius is estimated to be 6.6 Å from a theoretical fit of the relationship of relative permeability and cation radius.  相似文献   

16.
17.
The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.  相似文献   

18.
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.  相似文献   

19.
We investigated the uptake of inorganic elements (Be, Na, Mg, K, Ca, Sc, Mn, Co, Zn, Se, Rb, Sr, Y, Zr, Ce, Pm, Gd, and Hf) and the effect of Ca on their uptake in carrots (Daucus carota cv. U.S. harumakigosun) by the radioactive multitracer technique. The experimental results suggested that Na, Mg, K, and Rb competed for the functional groups outside the cells in roots with Ca but not for the transporter-binding sites on the plasma membrrane of the root cortex cells. In contrast, Y, Ce, Pm, and Gd competed with Ca for the transporters on the plasma membrane. The selectivity, which was defined as the value obtained by dividing the concentration ratio of an elemental pair, K/Na, Rb/Na, Be/Sr, and Mg/Sr, in the presence of 0.2 and 2 ppm Ca by that of the corresponding elemental pair in the absence of Ca in the solution was estimated. The selectivity of K and Rb in roots was increased in the presence of Ca. The selectivity of Be in roots was not affected, whereas the selectivity of Mg was increased by Ca. These observations suggest that the presence of Ca in the uptake solution enhances the selectivity in the uptake of metabolically important elements against unwanted elements.  相似文献   

20.
《Ibis》1894,36(3):447-460
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