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1.
合浦珠母贝两个种群染色体组型的分析 总被引：2，自引：0，他引：2
以北部湾和大亚湾两个地域的野生合浦珠母贝种群为研究对象，采用成贝的鳃组织．经空气干燥法制片进行染色体组型分析。结果表明两地种群的核型公式都为2N=28=16m 6sm 4st 2t．NF=50．但在染色体排序方面表现出较明显的群体差异。并与以往研究报道相比较．分析了不同的实验结果及可能产生差异的原因。 相似文献
2.
管角螺、细角螺的核型研究 总被引：2，自引：0，他引：2
以管角螺、细角螺鳃组织为材料,经过秋水仙素处理,空气干燥法制片,Giemsa染色,观察分析获得染色体核型。结果表明,管角螺核型公式为2n=60=44m+10sm+6t,染色体总臂数NF=114。细角螺核型公式为2n=42m+10sm+2st+6t,总臂数NF=112。两种螺的全套染色体中未发现次缢痕、随体,也无性染色体。 相似文献
3.
《广东海洋大学学报》2016,(3)
以洛氏鱥(Phoxinus lagowskii)肾组织为材料,采用腹腔注射植物血球凝集素(PHA)、秋水仙素和空气干燥法制备染色体标本,进行染色体组型分析。结果表明:洛氏鱥染色体为50条,核型公式为2n=50=24m+14sm+12t,臂数NF=88,未发现异型染色体、随体染色体和次缢痕。 相似文献
4.
利用常微分方程的定性理论,研究了两个种群具有非线性密度制约的捕食-被捕食者系统:dxdt=b0x(b1+b2x-b3x2)-b4xy,dydt=-cy+(αx-βy)y,的平衡点的性质,并证明了该系统存在唯一极限环的一个充分必要条件。 相似文献
5.
帝企鹅是南极生态的指示器,其种群栖息地分布变化对研究南极气候具有重要意义,但传统的人工实地调查难以获取全面、准确的种群栖息地信息。本文依据帝企鹅种群排泄物在卫星影像上的蓝、红波段和近红外与短波红外波段的反射率差异,提出2种可以有效判别种群排泄物的光谱指数（NDII、EI）,据此精确识别帝企鹅种群排泄物并确定其种群栖息地位置。根据2009年195景时相合适、质量较好的Landsat 7 ETM+卫星影像,获取了南极共计38个帝企鹅种群栖息地,其中新发现7处（Bowman Island , Dibble Glacier , Auster, Point Geologie , Cape Crozier , Brownson Islands和Rupert Coast）,消失2处（Amundsen Bay 和Ledda Bay）,另外25处（除Thuston Glacier, Luitpold, Sanae, Gould, Ragnhild和Beaufort Island外）位置未发生明显变化,实现了全南极帝企鹅种群栖息地的识别与定位。种群栖息地提取的正确率为94%,提取结果受限于影像质量和种群规模,且随着种群规模的提高,该方法的提取效果也越好。帝企鹅种群栖息地的分布与气候要素息息相关,种群栖息地往往倾向于气温较低和海冰密集度较高的区域,气候变化对每个种群栖息地的影响不同,因此气候与种群栖息地变化的具体关系需要长时间、区域性的观测进行研究。随着气温持续上升和海冰密集度的变化,南纬70°以北的种群栖息地面临较大的威胁,帝企鹅种群呈现向极点逐渐收缩的趋势。 相似文献
6.
【目的】研究棕点石斑鱼(Epinephelus tukula,♀)与蓝身大斑石斑鱼(Epinephelus fuscoguttatus,♂)杂交F1代(下称"金虎斑")的染色体核型。【方法】采用头肾-PHA注射法制备金虎斑染色体,并分析其核型。【结果与结论】金虎斑二倍体染色体数为48,包括23对端部着丝粒染色体,1对亚中部着丝粒染色体,核型公式是2n=48=2sm+46t,染色体臂数(NF)为50。与其他石斑鱼核型相比,金虎斑染色体核型特点符合典型的高位类群鱼类核型特征;根据染色体臂数,金虎斑属于特化类群。 相似文献
7.
利用常微分方程的定性理论，研究了两个种群具有非线性密度制约的捕食-被捕食者系统：dx/dt=box（b1＋b2x-b3x^2）-b4xy，dy/dt=-cy＋（ax-βy）y，的平衡点的性质，并证明了该系统存在唯一极限环的一个充分必要条件。 相似文献
8.
采用RAPD方法研究了洪湖微齿眼子菜种群的遗传多样性，矛初步探讨了它的遗传结构及影响因素。在97个脚标记中有28条（28．87％）是多态性标记，Shannon信息多样性指数分析表明该种群总的遗传多样性为0.193，说明洪湖微齿眼子菜种群的遗传多样性水平较低。研究发现距离和种群发展历史对洪湖微齿眼子菜种群的遗传结构有重要影响。 相似文献
9.
湛江沿海大黄鱼种群的研究 总被引：2，自引：0，他引：2
曹启华 《广东海洋大学学报》1998,18(2):15-16
徐闻和硇州两海区所产的大黄鱼,过去一直认为是同一种群－－粤西种群。通过生物学测定,发现在体长组成、年龄组成、体重组成和年渔获量方面,两者有显著的差异,应叙说了种群硇州种群。 相似文献
10.
哲罗鱼(Hucho taimen)染色体组型与DNA含量分析 总被引：1，自引：0，他引：1
采用体内注射PHA和秋水仙素、肾细胞短期培养、常规空气干燥法制备哲罗鱼(Hucho taimen)的染色体。对其肾细胞染色体数目统计分析表明,哲罗鱼染色体组有84条染色体,核型公式为2n=18m+16sm+34st+16t,其染色体总臂数(NF)为118。采用流式细胞分析仪测定哲罗鱼的DNA含量,与鸡血细胞标准对照的比值为2.23±0.17,以鸡红细胞DNA含量2.30pg·N~(-1)计,则哲罗鱼的体细胞DNA含量为5.12pg·N~(-1)。哲罗鱼染色体数目和DNA含量体现为四倍体特征。 相似文献
11.
The seasonal variations in phytoplankton community structure were investigated for the Sanggou Bay （SGB） and the adjacent Ailian Bay （ALB） and Lidao Bay （LDB） in Shandong Peninsula,eastern China.The species composition and cell abundance of phytoplankton in the bay waters in spring （April 2011）,summer （August 2011）,autumn （October 2011）,and winter （January 2012） were examined using the Uterm6hl method.A total of 80 taxa of phytoplankton that belong to 39 genera of 3 phyla were identified.These included 64 species of 30 genera in the Phylum Bacillariophyta,13 species of 8 genera in the Phylum Dinophyta,and 3 species of 1 genus in the Phylum Chrysophyta.During the four seasons,the number of phytoplankton species （43） was the highest in spring,followed by summer and autumn （40）,and the lowest number ofphytoplankton species （35） was found in winter.Diatoms,especially Paralia sulcata （Ehrenberg） Cleve and Coscinodiscus oculus-iridis Ehrenberg,were predominant in the phytoplankton community throughout the study period,whereas the dominance of dinoflagellate appeared in summer only.The maximum cell abundance of phytoplankton was detected in summer （average 8.08 × 103 cells L-1） whereas their minimum abundance was found in autumn （average 2.60 x 103 cellsL-1）.The phytoplankton abundance was generally higher in the outer bay than in the inner bay in spring and autumn.In summer,the phytoplankton cells were mainly concentrated in the south of inner SGB,with peak abundance observed along the western coast.In winter,the distribution of phytoplankton cells showed 3 patches,with peak abundance along the western coast as well.On seasonal average,the Shannon-Wiener diversity indices of phytoplankton community ranged from 1.17 to 1.78 （autumn 〉 summer 〉 spring 〉 winter）,and the Pielou＇s evenness indices of phytoplankton ranged from 0.45 to 0.65 （autumn 〉 spring 〉 summer〉 winter）.According to the results of canonical correspondence analysis,phosphate level w 相似文献
12.
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｐｒｏｄｕｃｔｉｏｎｏｆｐｈｙｔｏｐｌａｎｋｔｏｎｉｓｔｈｅｆｉｒｓｔｔａｃｈｅｉｎｔｈｅｐｒｏｄｕｃｔｉｏｎｂｙｍａｒｉｎｅｏｒｇａｎｉｓｍｓａｎｄｉｎｔｈｅｍａｒｉｎｅｆｏｏｄｃｈａｉｎ .Ｋｎｏｗｌｅｄｇｅｏｆｐｒｉｍａｒｙｐｒｏｄｕｃｔｉｏｎｉｎｍａｒｉｎｅｗａｔｅｒｓｉｓｐｒｅｒｅｑｕｉｓｉｔｅｆｏｒｅｘｐｌｏｉｔａｔｉｏｎａｎｄｍａｎａｇｅｍｅｎｔｏｆｔｈｅｏｃｅａｎ’ｓｌｉｖｉｎｇｒｅｓｏｕｒｃｅｓ.Ｔｈｅｐｒｉｍａｒｙｐｒｏｄｕｃｔｉｏｎｉｎｍａｒｉｎ… 相似文献
13.
Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou B ay, were analyzed to determine the spatiotemporal variations in temperature, light, nutrients (NO-3-N, NO-2-N, NH+4-N, SiO2-3-Si, PO3-4-P), phytoplankton, and primary production in Jiaozhou Bay. The results indicated that only silicate correlated well in time and space with, and had important effects on, the characteristics, dynamic cycles and trends of, primary production in Jiaozhou Bay. The authors developed a corresponding dynamic model of primary production and silicate and water temperature. Eq.(1) of the model shows that the primary production variation is controlled by the nutrient Si and affected by water temp erature; that the main factor controlling the primary production is Si; that water temper ature affects the composition of the structure of phytoplankton assemblage; that the different populations of the phytoplankton assemblage occupy different ecologica l niches for C, the apparent ratio of conversion of silicate in seawater into phytoplankton biomas and D, the coefficient of water temperature's effect on phytoplankton biomass. The authors researched the silicon source of Jiaozhou Bay , the biogeochemical sediment process of the silicon, the phytoplankton predominan t species and the phytoplankton structure. The authors considered silicate a limit ing factor of primary production in Jiaozhou Bay, whose decreasing concentration of silicate from terrestrial source is supposedly due to dilution by current and up take by phytoplankton; quantified the silicate assimilated by phytoplankton, the intrins ic ratio of conversion of silicon into phytoplankton biomass, the proportion of silicate uptaken by phytoplankton and diluted by current; and found that the primary production of the phytoplankton is determined by the quantity of the silicate assimilated by them. The phenomenon of apparently high plant-nutrient concentrations but low phytoplankton biomass in some waters is reasonably explained in this paper. 相似文献
14.
15.
Biomarkers including brassicasterol, dinosterol and alkenone in sediments are used as indicators to reconstruct changes to the phytoplankton community in surface and sub-aerial sediments of Prydz Bay, Antarctica. The results indicate that the bio- marker records in surface and core sediment samples changed with time and space. The total content of phytoplankton biomarkers ranges from 391.0--1 470.6 ng.g-l. The phytoplankton biomass has increased in Prydz Bay over the past 100 years. This variation may be mainly related with climate change in the region. The total biomarker contents in surface sediments from 5 stations in Prydz Bay are in the range of 215.8--1 294.3 ng.g4. The phytoplankton biomass in Prydz Bay is higher than that outside of the bay. This is similar to the distributions of chlorophyll a, organic carbon and biogenic silica in surface waters determined through in situ investigation. Such consistency indicates a coupling between the bottom of the ocean and biogeochemical processes in the upper water. 相似文献
16.
Source and spatial distributions of particulate organic carbon and its isotope in surface waters of Prydz Bay,Antarctica, during summer 总被引：1，自引：0，他引：1
In this study, we investigated the distributions of sea-surface suspended particulate organic carbon （POC） and its stable isotope （δ13C POC） in Prydz Bay, Antarctica, and examined the factors influencing their distribution, sources, and transport. We used measurements collected from 61 stations in Prydz Bay during the 29th Chinese National Antarctic Research Expedition, in combination with remote sensing data on sea surface temperature （SST）, chlorophyll a concentration, and sea ice coverage. The POC concentration in the surface waters of Prydz Bay was 0.28-0.84 mg.L-1, with an average concentration of 0.48 mg.L-1. The δ13C POC value ranged from -29.68‰ to -26.30‰, with an average of-28.01‰. The concentration of suspended POC was highest in near-shore areas and in western Prydz Bay. The POC concentration was correlated with chlorophyll a concentration and sea ice coverage, suggesting that POC was associated with phytoplankton production in local water columns, while the growth of phytoplankton was obviously affected by sea ice coverage. The δ13C poc value in suspended particles decreased gradually towards the outer waters of Prydz Bay, while in eastern Prydz Bay the δ13Cpoc value become gradually more negative from nearshore to deep-water areas, suggesting that δ13C poc was mainly influenced by CO2 fixation by phytoplankton. The δ13C POC value in suspended particles near Zhongshan Station was significantly negative, possibly as a result of the input of terrigenous organic matter and changes in the phytoplankton species composition in the nearshore area. 相似文献
17.
WilliamA．Gough 《地球科学与环境学报》2004,26(4):41-45
Hudson海湾的河川径流量在整个加拿大河川径流量中占有很大的比例，所有河流排泄量约30％流人了Hudson和James海湾。研究了该地区河川径流与当地气候变化之间的关系；把河川向James海湾的排泄与曼尼托巴省Churchill地区海水位的变化联系起来，讨论了其对Hudson海湾再循环的影响；根据曼尼托巴省Churchill地区海水位的观测资料重点讨论了该地区海水位在历史时期的变化及未来的预测变化等三个重要水文问题。最后指出了今后在Hudson海湾地区进行水文研究的方向。 相似文献
18.
Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou Bay, were analyzed to determine the spatiotemporal variations in temperature, light, nutrients (NO3^--N, NO2^--N, NH4^ -N, SIO3^2--Si, PO4^3--P), phytoplankton, and primary production in Jiaozhou Bay. The results indicated that only silicate correlated well in time and space with, and had important effects on, the characteristics, dynamic cycles and trends of, primary production in Jiaozhou Bay. The authors developed a corresponding dynamic model of primary production and silicate and water temperature. Eq. ( 1 ) of the model shows that the primary production variation is controlled by the nutrient Si and affected by water temperature; that the main factor controlling the primary production is Si; that water temperature affects the composition of the structure of phytoplankton assemblage; that the different populations of the phytoplankton assemblage occupy different ecological niches for C, the apparent ratio of conversion of silicate in seawater into phytoplankton biomas and D, the coefficient of water temperature‘s effect on phytoplankton biomass. The authors researched the silicon source of Jiaozhou Bay, the biogeochemical sediment process of the silicon, the phytoplankton predominant species and the phytoplankton structure. The authors considered silicate a limiting factor of primary production in Jiaozhou Bay, whose decreasing concentration of silicate from terrestrial source is supposedly due to dilution by current and uptake by phytoplankton; quantified the silicate assimilated by phytoplankton, the intrinsic ratio of conversion of silicon into phytoplankton biomass, the proportion of silicate uptaken by phytoplankton and diluted by current; and found that the primary production of the phytoplankton is determined by the quantity of the silicate assimilated by them. The phenomenon of apparently high plant-nutrient concentTations but low phytoplankton biomass in some waters is reasonably explained in this paper. 相似文献
19.
LOU Angang） ）* HU Yuebo） KUANG Liang） ZHANG Xueqing） DU Peng） ）） College of Environmental Science Engineering Ocean University of China Qingdao P. R. China ） Key Lab of Marine Environmental Science Ecology P. R. China 《中国海洋大学学报(英文版)》2009,8(1)
The 3-D ECOMSED ocean model was applied to establish a time-dependent boundary model for Jiaozhou Bay (JZB), in which the operator-splitting technique was used and the ‘dry and wet’ method was introduced. The influence caused by JZB reclamation on the surface level, residual currents, tidal system and tidal energy of M2 tidal system were predicted and analyzed. The results show that JZB reclamation has slight impact on the M2 tidal system, in which the variation of amplitude and phase is less than 1%.The ch... 相似文献
20.
The densities of 36 water samples from the Huanghe River estuary and Bohai Bay were determinedby a magnetic float densimcter under three temperatures from 15℃ to 25℃.All the measured densities ofsamples were greater than that of the values calculated from the International Equation of State of Seawater.The differences between the measured and calculated densities increased with the decrease of salinities.The dif-ferences appeared exponentially correlated with[Ca~(2+)]/s,[Mg~(2+)]/s and[SO_4~(2-)]/s,and had"s"type curverelationship with the alkalinity in all salinity range.But in the salinity ranging from 25.72 to 31.57,therelationships were all linear.The density difference can be estimated from the equation △ρ（10~3kg·m~(-3)）=（-2.79+236.5([Ca~(2+)]/s)/(-9.7464×10~（-3）+[Ca~(2+)]/s).It was the high alkalinity and[Ca~(2+)]/s that resulted in the measured densi-ties of seawaters being higher than the calculated densities in the Huanghe estuary and Bohai Bay. 相似文献