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1.
海南淡水龟类贸易现状与管理建议   总被引:10,自引:0,他引:10  
2002–2004年,对海南野生淡水龟类贸易进行了调查。调查发现海南所有市县都存在野生龟类贸易,有野生龟类贸易的农贸市场22个,占调查农贸市场总数的19.6%;有野生龟类贸易的乡镇64个,占调查乡镇总数的65.3%;野生龟类收购点103个,野生淡水龟共489只。野生龟贸易所涉及的淡水龟类共10种,占海南淡水龟分布总种数的90%以上,其中3种是国家二级重点保护动物,6种是列入《濒危野生动植物种国际贸易公约》附录II的物种。按照《中国濒危动物红皮书(两栖类和爬行类)》,1种为极危物种,8种为濒危物种,1种为易危物种。在个体数量方面,以锯缘摄龟(Pyxideamouhotii)、黄额盒龟(Cuoragalbinifrons)、四眼斑水龟(Sacaliaquadriocellata)和中华花龟(Ocadiasinensis)较多,平胸龟(Platysternonmegacephalum)、地龟(Geoemydaspengleri)、中华鳖(Pelodiscussinensis)较少,三线闭壳龟(Cuoratrifasciata)、黄喉拟水龟(Mauremysmutica)和山瑞鳖(Paleasteindachneri)极其稀少。龟类市场价格差异很大,从2002年到2004年,各种龟的价格都有不同幅度的上涨。分析表明:淡水龟类非法捕猎与贸易在海南普遍存在,过度捕猎对海南淡水龟类构成了严重威胁,而野生龟贸易则是导致过度捕猎的主要原因。本文在分析和探讨海南野生淡水龟类贸易的现状、原  相似文献   

2.
四眼斑水龟在海南岛的地理分布调查   总被引:1,自引:1,他引:0  
采用查阅文献、走访调查和野外调查三种方法相结合,对四眼斑水龟在海南岛的地理分布进行了调查。对18个市县的103个乡镇进行了走访调查;野外调查中采用系统抽样法和笼捕法,对黎母山、尖峰岭、霸王岭、南茂岭、万俄岭和文教河上游6个研究点进行了调查。结果表明:1)四眼斑水龟分布于海南岛中部和西南部山区以及丘陵地区,除了海口、文昌、临高、定安和澄迈5个市县没有分布外,其它13个市县均有分布,其中8个市县为本次调查的分布新记录;2)四眼斑水龟栖息于海拔170~640m的山区溪流环境,而在平原、台地、滩涂地区以及比较大的江河、水库和湖泊沿右分布。  相似文献   

3.
淡水龟科具闭壳结构龟类分类及系统进化研究进展   总被引:1,自引:0,他引:1  
闭壳龟类是淡水龟科(Bataguridae)中一群具有"闭壳"结构的水栖或半水栖龟类的总称,即腹甲的腹盾和胸盾之间以可动的铰链韧带相连,使背甲和腹甲可以全部或部分闭合,它们是盒龟属(Cistoclemmys)、闭壳龟属(Cuo-ra)、锯缘龟属(Pyxidea)、齿缘龟属(Cyclemys)和果龟属(Notochelys),前4个属的龟类在中国均有分布。近几十年来,由于食用、传统中医药开发和宠物贸易的兴起,导致许多闭壳龟类野生物种数量急剧减少,并且当前许多亚洲闭壳龟的分类工作过多的依赖于市场购买的物种样本,这就使我们对闭壳龟属及种的归属划分变的较困难,因此对闭壳龟类物种种的界限的划分及属间系统发育关系的研究仍然是一个艰巨的挑战。通过对淡水龟科具有闭壳结构龟类的形态学研究,细胞遗传学研究以及分子系统学研究等进行了综述,以期为闭壳龟类的相关保护研究提供参考。  相似文献   

4.
基于线粒体Cyt b基因的全长序列探讨闭壳龟类的系统进化   总被引:1,自引:0,他引:1  
采用PCR技术对淡水龟科具闭壳结构的黄缘盒龟、黄额盒龟、金头闭壳龟、潘氏闭壳龟、锯缘龟和白腹摄龟的线粒体Cytb基因的全长序列进行了PCR扩增和序列测定,并结合GenBank中16种淡水龟科物种的同源序列,进行了序列变异和系统发生分析。经C lustalX1.8软件对位排列后共有1154个位点,其中可变位点413个,简约信息位点301个;A+T的平均含量(56.5%)高于G+C(43.5%)。在氨基酸密码子中,第一位富含A,第二位富含T,第三位富含C;碱基转换/颠换率为5.97,碱基替换多发生在密码子第三位。以中华鳖和马来鳖为外群,通过最大简约法,最大似然法和贝叶斯法重建了分子系统树,均具有一致的拓扑结构,结果表明:金头闭壳龟和潘氏闭壳龟最先聚成一支,再和三线闭壳龟聚成一组,说明形态上相似的三种闭壳龟亲缘关系最近;闭壳龟属、盒龟属和单种锯缘龟属聚成一个单系的闭壳龟群,建议合并为闭壳龟属;齿缘龟属和果龟属聚为一支,它们与新的闭壳龟属关系较远,揭示闭壳结构的形成不是由一个共同祖先分化而来;乌龟属、花龟属和拟水龟属三属为并系起源,建议三属可以合并为一属。  相似文献   

5.
2006~2011年采用野外调查和访问调查相结合的方法,对广东鼎湖山国家级自然保护区爬行动物进行了专项调查研究。迄今,该保护区已记录爬行动物2目12科54种,其中6种为本次调查发现的新纪录,分别是截趾虎Gehyra mutilata、丽棘蜥Acanthosaura lepidogaster、棕黑腹链蛇Amphiesma sauteri、黑领剑蛇Sibynophis collaris、细白环蛇Lycodon subcinctus和乌龟Mauremys reevesii。本次调查野外发现爬行动物共38种,其中包括珍稀濒危物种平胸龟Platysternon megacephalum,16种文献有记载的爬行动物在本次调查中未发现。访问调查发现6只四眼斑水龟Sacalia quadriocellata,很可能来自鼎湖山。基于调查结果,对该保护区爬行动物多样性及受胁因素进行了探讨,并提出了4点保护管理建议。  相似文献   

6.
海南岛黎母山四眼斑水龟对春季生境的选择性   总被引:11,自引:1,他引:10  
2004年3—4月,在海南岛黎母山采用系统抽样法对四眼斑水龟春季生境选择进行了初步研究。在海拔170~1170m设196个研究样点,共1392个笼捕日。其中在海拔170~470m的26个布笼点共捕获四眼斑水龟36只,而在海拔470~1170m未捕获到四眼斑水龟。采用Kruskal Wallis检验,对海拔500m以下四眼斑水龟利用样地(n=26)和海拔500m以上的对照样地(n=26)的生态因子差异显著性进行检验。结果表明,两类样地的海拔、植被类型、植被盖度、落叶厚度、土壤类型、坡度、水面宽、水深、水面流速、基底类型、露石率、食物丰度、干扰距离13个生态因子差异均显著,仅石洞数目差异不显著。说明海拔500m以上和以下的环境差异较大。主成分分析结果表明,影响四眼斑水龟生境选择的主要生态因子依次为海拔、干扰距离、植被盖度、土壤类型、水深和落叶厚度。而植被类型、食物丰度、露石率、基底、石洞数目、坡度、水面宽和水面流速8个生态因子的影响不明显。保护好近河岸植被和提高当地群众对龟类的保护意识对四眼斑水龟的保护十分重要。  相似文献   

7.
分布于海南岛的四眼斑水龟Sacalia quadriocellata种群长期被认为与其他地区的四眼斑水龟没有差别,但是分子生物学方法发现,它与其他地区四眼斑水龟种群存在较大遗传差异,形态学研究的结果也支持分子生物学将其列为独立物种的建议,但该物种目前尚没有明确的中文和拉丁学名。根据国际龟类物种命名习惯及先验原则,建议将分布于海南岛的四眼斑水龟独立新种的拉丁学名命名为Sacalia insulensis Adler,1962,并拟定中文名为海南四眼斑水龟。  相似文献   

8.
海南岛黎母山四眼斑水龟种群密度与空间分布格局   总被引:2,自引:1,他引:1  
2004年3~7月,采用系统抽样法在海南岛黎母山对四眼斑水龟(Sacalia quadriocellata)种群密度与空间分布进行了调查,采用Cassie指数、David&Moore指数、Morisita指数和Lloyd指数测定了四眼斑水龟种群空间分布格局。结果表明,(1)四眼斑水龟种群分布于海拔170~470m范围内,在垂直梯度上呈现不连续的分布状态;(2)在海拔170~470m范围内种群相对密度为0.011~0.050只/笼捕日;(3)种群空间分布呈现聚集分布格局;(4)资源的空间分布特点和人为干扰可能对四眼斑水龟种群密度及空间分布格局有重要影响。  相似文献   

9.
金头闭壳龟的分布及生存现状调查   总被引:5,自引:0,他引:5  
1998年6月~2004年7月,经历时6年的调查访问,了解到金头闭壳龟(Cuora aurocapitata)生活于水质清澈的溪流中,尤其是落差较大的水潭;食物主要为溪蟹、小鱼虾和水生昆虫;近20年所捕获的该龟均来自皖南的青弋江流域。作者经过40多条样带的野外调查,未曾亲自捕获金头闭壳龟,证明该龟野外种群处于极危状态。国内各高等院校和科研单位所收集的该龟标本不足20只,国内拥有该龟的养龟爱好者和养殖户约20余家,人工饲养成龟共80只左右,人工繁殖出的幼龟不超过100只。金头闭壳龟的生存现状正面临严重危机,应采取有效的保护措施。  相似文献   

10.
2005年7~9月(雨季)和2006年2~4月(旱季),对海南吊罗山国家级自然保护区海拔900~1100 m地区的黄额闭壳龟Cuora galbinifrons种群密度进行了调查.在调查样区内根据植被类型随机选取6个调查样区,424个布笼点,6360个笼捕日,调查面积6.36 km2,捕获黄额闭壳龟5只,其中,人工林中...  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.
16.
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   

17.
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   

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.
《Ibis》1894,36(3):447-460
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20.
Nine blood group systems of goats were identified using 12 caprine reagents produced by absorption of alloimmune antisera. The caprine C blood group system, possibly homologous to the ovine C blood group system, was characterized by two reagents and shown to be controlled by three alleles,C 12,C 25, andC . A more complex blood group system of goats, designated G, was identified using three reagents and shown to be controlled by six codominant alleles (G 10.19.20,G 10.19,G 10.20,G 10,G 19,G 20) and a recessive allele (G ). A further seven one-factor two-allelic systems were identified by seven reagents. The nine genetic systems provided exclusion probabilities of 0.479, 0.492, 0.548, and 0.572 in Australian Angora, Dairy, Cashmere, and Texan Angora goat breeds, respectively. This work was supported by a grant from the Australian Stud Book, Alison Road, Randwick, New South Wales 2031, Australia.  相似文献   

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