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1.
<正>黑龙江(蒙语称哈拉穆河,俄语称阿穆尔河)是东北亚地区较大的河流,也是中国和俄罗斯的界河。黑龙江始于石勒喀河与额尔古纳河汇流处,最终注入鄂霍次克海。干流长约4 300千米,以结雅河和乌苏里江入口作为分界点将黑龙江分成上、中、下游3段。有松花江、乌苏里江、结雅河、布列亚河等支流200余条,流域面积达184.3万平方千米。黑龙江流域是野生莲自然分布区的最北界,在黑龙江中下游地区的旧河床、泡沼等静水湿地中,有众多野生莲种群分布。经  相似文献   

2.
采用实验生态学的方法研究了不同温度和流速对两个年龄组洛氏鱥呼吸代谢的影响。结果表明,1龄和2龄洛氏鱥在4℃水体中基本不摄食生长十分缓慢,随着水体温度升高,鱼类摄食和生长情况出现好转。在温度4℃增高至28℃的过程中,除流速16cm/s和18cm/s条件下水温由24℃升28℃时耗氧率出现降低外,其余流速下洛氏鱥耗氧率均随着温度升高而增加,呈典型的指数增长趋势Y=aebx,R2值均高于0.90;在流速由8cm/s增至18cm/s的过程中,虽然1龄组在低于20℃和2龄组低于24℃水体中耗氧率随流速增加而增加,但1龄组在温度24、28℃和2龄组在28℃的水体中当流速增至16cm/s时耗氧率达到最大值,1龄组持续30min和2龄组持续1h后出现鱼体紧贴栏鱼网的现象。通过分析得出,洛氏鱥的呼吸代谢受到温度、水流和个体大小等因素的相互影响,个体较大的2龄洛氏鱥对水环境的适应范围明显强大于1龄鱼,流速为12—14cm/s温度为16—24℃和流速为16cm/s温度为16—20℃是1龄洛氏鱥理想养殖条件,流速12—16cm/s温度8—24℃是2龄洛氏鱥理想养殖条件。  相似文献   

3.
实验旨在探索不同C/N生物絮团对急性铜暴露洛氏鱥免疫抑制、炎症反应与氧化应激的保护作用。挑选480尾洛氏鱥(Rhynchocypris lagowskii Dybowski)幼鱼(10±0.15) g,随机分成4组,每组3个重复,每个重复40尾鱼。对照组饲喂商品料(C/N 10.8﹕1),实验组选择葡萄糖为外添碳源调节C/N 15﹕1(Ⅱ组)、C/N 20﹕1(Ⅲ组)和C/N 25﹕1(Ⅳ组),生长实验为56d,之后进行为期96h的急性铜暴露胁迫实验。结果表明,各实验组中免疫、抗氧化酶活性与炎症因子含量随着C/N的增加先升高后下降。其中,与对照组相比,Ⅲ和Ⅳ组血清碱性磷酸酶(AKP)、酸性磷酸酶(ACP)、溶菌酶(LSZ)、一氧化氮合酶(NOS)、补体C3、C4和免疫球蛋白M(IgM)水平显著升高(P<0.05),而Ⅲ和Ⅳ组之间补体C3和C4水平差异不显著(P>0.05);Ⅲ和Ⅳ组血清过氧化氢酶(CAT)、抗坏血酸(ASA)、超氧化物歧化酶(SOD)、总抗氧化能力(T-AOC)、谷胱甘肽过氧化物酶(GSHPX)与谷胱甘肽还原酶(GR)酶活性显著高于对照组(P<0.05...  相似文献   

4.
温度对绥芬河滩头雅罗鱼胚胎发育的影响   总被引:5,自引:1,他引:4       下载免费PDF全文
  相似文献   

5.
为了研究饲料蛋白质水平对洛氏鱥(Rhynchocypris lagowskii Dybowski)生长、非特异性免疫及蛋白质合成的影响, 以洛氏鱥幼鱼[(6.98±0.01) g/尾]为研究对象, 以鱼粉、棉粕、豆粕及菜粕为蛋白源, 配制成蛋白质水平为24.98%、30. 02%、34.99%、40.01%和44.98%的5种等能、等脂肪的配合饲料, 进行为期8周的饲养试验。结果表明, 在试验条件下, 随着饲料蛋白质水平的升高, 洛氏鱥的终末体质量、特定生长率、增重率均呈先升高后降低的趋势, 其中34.99%和40.01%组洛氏鱥的终末体质量、特定生长率及增重率显著高于24.98%组(P<0.05); 随着饲料蛋白质水平的升高, 洛氏鱥饲料效率和蛋白质效率呈先升高后降低的趋势, 其中40.01%组洛氏鱥饲料效率和蛋白质效率显著高于24.98%组(P<0.05), 但与30.01%、34.99%和40.01%组差异不显著(P>0.05)。通过折线回归分析得出, 饲料蛋白质水平为35.89%时, 洛氏鱥的特定生长率最高; 饲料蛋白质水平为36.11%时, 洛氏鱥饲料效率最高。洛氏鱥肌肉中粗蛋白质含量随饲料蛋白质水平的升高呈先上升后下降趋势, 其中, 40.01%组洛氏鱥肌肉中粗蛋白质含量显著高于24.98%、30.02%、34.99%和44.98%组(P<0.05); 而洛氏鱥肌肉中粗脂肪含量随饲料蛋白质水平的升高呈先下降后上升趋势, 其中, 40.01%组显著低于24.98%、30.02%和34.99%组(P<0.05), 但与44.98%组差异不显著(P>0.05)。洛氏鱥肝胰脏的碱性磷酸酶(AKP)、酸性磷酸酶(ACP)、超氧化物歧化酶(SOD)和溶菌酶(LZM)活性随饲料蛋白质水平的升高呈先上升后下降的趋势, 其中40.01%组洛氏鱥AKP、ACP、SOD和LZM活性显著高于24.98%、30.02%、34.99%和44.98%组(P<0.05); 洛氏鱥白肌中RNA含量和RNA/DNA比值随饲料蛋白质水平的升高呈先升高后降低的趋势, 其中40.01%组洛氏鱥白肌中RNA含量和RNA/DNA显著高于24.98%、30.02%、34.99%和44.98% (P<0.05)。通过折线模型回归分析可知饲料蛋白质水平为36.10%时, 洛氏鱥白肌中RNA含量最高; 饲料蛋白质水平为35.91%时, 洛氏鱥白肌中RNA/DNA比率最高。在洛氏鱥配合饲料中, 最适宜蛋白质需求水平为34.99%—40.01%。  相似文献   

6.
水体中水生维管束植物的种类粗成及数量的多寡,对于渔业是有着密切关系的。有些主要的经济鱼类(如草鱼、鳊、鲤、鲫等)是以水生维管束植物作主要的食料,也有很多产粘着性卵的鱼类(如鲤、鲫、鲶等)要把卵产在水生植物上;一些高等水生植物的多寡也直接或间接地影响底棲生物和浮游生物的生长繁殖。另一方面,有些高等水生植物的大量繁殖,  相似文献   

7.
水体中水生维管束植物的种类组成及数量的多寡,对于渔业是有着密切关系的。有些主要的经济鱼类(如草鱼、鳊、鲤、鲫等)是以水生维管束植物作主要的食料,也有很多产粘着性卵的鱼类(如鲤、鲫、鲶等)要把卵产在水生植物上;一些高等水生植物的多寡也直接或间接地影响底棲生物和浮游生物的生长繁殖。另一方面,有些高等水生植物的大量繁殖,对于鱼类却有不良的影响。因此,调查了解流域中水生高等植物的种类和数量对于正确地估价水体生产力是有帮助的。  相似文献   

8.
黑龙江水系不同倍性鲫鱼的遗传多样性   总被引:1,自引:0,他引:1  
贾智英  石连玉  刘晓峰  孙效文 《遗传》2008,30(11):1459-1465
摘要: 利用12对微卫星标记对黑龙江水系6个野生鲫鱼不同倍性群体进行遗传结构分析。结果表明: 6个采集群体的平均等位基因数为5.8~6.8, 平均有效等位基因数为2.8~4.6, 平均期望杂合度为0.5592~0.6962, 平均多态信息含量为0.5962~0.6481, 说明这几个群体遗传多样性水平较高。根据d值, 各群体均有不同程度的偏离Hardy-Weinberg平衡的现象, 均表现为杂合度过度。Kruskal-Wallis 检验表明两种倍性、6个采集群体鲫鱼遗传多样性差异不显著, 没有发现三倍体鲫由于倍性增加而出现额外的等位基因片段。群体间基因分化系数(GST)为0.0398, 表明群体间存在轻度遗传分化。聚类分析表明, 同水体两种鲫鱼亲缘关系最近, 不同采集群体间松花江与乌苏里江分化最小, 月亮湾与新荒泡其次, 双凤水库群体分化最大  相似文献   

9.
黄河水系对流域碳分布的影响   总被引:3,自引:0,他引:3       下载免费PDF全文
本文利用区段模型并以土壤流失资料和水文资料为基础,计算黄河水系碳输运的诸特征量。结果表明:黄河水系的碳输运主要表现为无机离子态碳和悬浮态碳,它们的输运量主要受土壤流失量和径流量的影响,并可表示为相关性较高的线性回归函数;黄河流域各区段的碳的源汇功能状况取决于土壤流失与泥沙沉积的总效果,具体讲,河源至安宁渡段和河口至三门峡段为主要的碳输运之源,其余则为主要的碳输运之汇。  相似文献   

10.
辽宁省河流水系及流域的遥感解译   总被引:4,自引:0,他引:4  
水资源是人民生活、生产不可缺少的重要资源,随着人口增长和工业发展,水资源供需矛盾日益突出,水资源的合理开发利用是当前急需解决的问题,而河流水系分布及流域面积的准确计算是开发利用的基础。1984年辽宁省曾进行第一次水资源普查工作,由于时间变迁和当时技术水平的限制,许多河流水系分布、流域面积等基础资料己不能准确反映当前状况。本研究利用美国地球资源卫星TM数字图像资料,选用ER-Mapper图像处理软件,对辽宁省河流水系及流域进行遥感解译。采用多比例尺、多波段、多时相的解译方法,同时还进行了直方图均衡化处理、滤波处理、线性变换等多种图像处理技术。采用波谱间关系法,建立了河流水系和流域遥感解译标志,同时采用主成分分析方法进行海岸线的遥感解译。计算了辽宁省主要河流长度及流域面积,与第一次水资源普查时的计算结果进行了对比分析,并探论其变化的原因。  相似文献   

11.
将2004年4~12月对木里县木里河、水洛河流域的鸟类调查结果与1928年美国博物学家约瑟夫.洛克(Joseph F Rock)在该区域内的鸟类调查记录比较,结果表明:①2004年调查的种类为123种,少于1928年调查记录139种,而且2004年调查的时间更长;②2004年调查鸟类群落的多样性指数和均匀度都小于1928年;③2004年调查鸟类的优势种有5种,常见种12种,主要为农耕-民居生境鸟类,1928年没有优势种,常见种有35种,主要为森林-灌丛生境鸟类;④鸟类区系构成没有产生大的变化。优势类群变化的主要原因是海拔3000m以下森林和灌丛生境受到干扰,蜕变为农耕地-民居生境,该区域的生境与1928年相比,已受到了破坏。  相似文献   

12.
13.
The study of tooth wear among prehistoric and recent populations has frequently been concerned with the rate and pattern of wear over the dental arches. In this report we considered the question of tooth wear variation among collections of Australian Aboriginal crania recovered from several sites along the Murray River in Southeastern Australia. These crania represent the remains of relatively recent populations from about 2,000 years ago until the early 19th century. The degree of tooth wear for each dental arch was recorded by an established method of determining the ratio of exposed dentin. The pattern or distribution of wear over each arch was summarized by principal component analysis. The mean wear degree and pattern were compared among four geographical grouping of crania separated by up to 700 miles of river frontage. Our results showed, as expected, a significant difference between the well-defined population at the Lower Murray site (Swanport) and the three upriver groups. However, there were significant differences among these three collections as well. Sexual dimorphism was noted but was only significant in the Lower Murray group; the mean wear was greater and also more variable among the males. At the second of the Middle Murray sites the pattern of wear was different and the degree of wear was significantly less than in the other groups. A possible explanation for this diversity may be environmental and subsistence base differences. The evidence from the Lower Murray supports this possibility, but the differences among the other three groups are not as clearly established. However, our results do suggest that the Murray Black collection, from which these crania were obtained, may not be as homogeneous a group as previously believed.  相似文献   

14.
Sera collected from inhabitants of the Tana River valley in 1971 were examined for antibody to tanapox virus. Neutralizing antibody was present in 16·3%. The levels of antibody and its presence in two children under the age of 10 years indicated that infection had been occurring in the area since the reported outbreak in 1962. A comparison of the incidence and distribution of antibodies in the same sera to West Nile virus revealed marked similarities suggesting that tanapox, like West Nile virus infections, might be transmitted in the same way—namely, by a culicine mosquito.  相似文献   

15.
The developmental stages of 12 Erythrocebus patas embryos, ranging in gestational age from 30 to 50 days, is described. The pattern of embryogenesis in E. patas closely parallels the anatomic characteristics of human and other nonhuman primate embryos between stages 12 and 23. However, there is a delay in development in E. patas similar to that observed in human embryos which differs from the macaques and baboons. This temporal difference in the embryonic period is an important factor in the design and analysis of early pregnancy studies in this species.  相似文献   

16.
The effects of development and disturbance on schooling and shoaling were observed in laboratory-raised minnows. Both behaviours were present at the onset of free swimming. Shoaling increased to become the most important behaviour by 3 weeks after emergence from gravel, while the main increase in schooling behaviour occurred at 4 weeks. These changes were accompanied by rises in elective group size and in the number of following responses, and by a decrease in nearest neighbour distance. The increases in social behaviour were observed at an earlier stage in the same minnows threatened by a standard net chase. The main increase in schooling in disturbed minnows took place between 3 and 4 weeks after emergence; after this time schooling became the dominant behaviour. Disturbed fish were also more likely to follow another minnow during an encounter.  相似文献   

17.
通过人工授精获得受精卵,利用数码显微镜进行连续观察和拍照记录,对沱江宽体沙鳅胚胎发育特征进行了详细观察和描述,并确定了到达各发育期所需的时间.成熟卵直径为0.9~1.1 mm.受精卵卵膜吸水膨胀之后直径为1.6~1.9 mm,半漂流性.卵膜直径较小是区分宽体沙鳅和其他鳅科漂流性鱼卵的标志性特征.水温23℃±0.5℃,受精卵历时27 h孵出.胚胎发育过程可划分为7个阶段、28个发育期.初孵仔鱼全长约为3.5~3.8 mm.建议水利工程规划及建设中应该保留满足漂流性卵胚胎发育的足够长的天然河段.  相似文献   

18.
The minnow (Phoxinus phoxinus) was raised up to the stage of swim bladder inflation at temperatures between 10 degrees C and 25 degrees C, and the time of development significantly decreased at higher temperatures. Accordingly, initiation of cardiac activity was observed at day 2 in 25 degrees C animals and at day 4 in 12.5 degrees C animals. Only a minor increase in body mass was observed during the incubation period, and, at the end of the incubation period, animals raised at 25 degrees C did not have a significantly lower body mass compared with animals raised at 15 degrees C. Metabolic activity, determined as the rate of oxygen consumption of a larva, increased from 3.3 to 19.5 nmol/h during development at 15 degrees C and from 5.6 to 47.6 nmol/h during development at 25 degrees C. Heart rate showed a clear correlation to developmental stage as well as to developmental temperature, but at the onset of cardiac activity, diastolic ventricular volume and also stroke volume were higher at the lower temperatures. Furthermore, stroke volume increased with development, except for the group incubated at 12.5 degrees C, in which stroke volume decreased with development. Initial cardiac output showed no correlation to incubation temperature. Although metabolic activity increased severalfold during development from egg to the stage of swim bladder inflation at 15 degrees C and at 25 degrees C, weight-specific cardiac output increased only by approximately 40% with proceeding development. At 12.5 degrees C, cardiac output remained almost constant until opening of the swim bladder. The data support the notion that oxygen transport is not the major function of the circulatory system at this stage of development. The changes in heart rate with temperature appear to be due to the intrinsic properties of the pacemaker; there was no indication for a regulated response.  相似文献   

19.
The pomegranate has been used traditionally in Coruh Valley in Turkey for a long time; fruits are harvested from wild, semi-domesticated and cultivated trees. In the valley, it occurs in general along with olive trees. We sampled 23 wild-grown pomegranate genotypes sampled from different parts of Coruh Valley and compared them using RAPD primers to determine genetic variability. Eighty-six RAPD primers were used for molecular characterizations, among which 12 gave reliable polymorphic patterns. These primers generated 145 RAPD bands of which 91% were polymorphic. The highest polymorphism ratio was observed with primers OPY06, OPY13, OPBA03, OPBB03, OPBB07, and OPBB09 (100%), while the lowest was with OPBB09 and OPBB10 (75%). The band size was between 250 and 2400 bp. There were five main clusters in the dendrogram; the highest genetic similarity was 0.24 and the lowest was 0.08.  相似文献   

20.
Concurrent infections with vector-borne pathogens affected a cattle herd in Switzerland, and one of the pathogens was identified as Babesia bigemina, which had never been observed in this country before. Therefore, a survey of the occurrence of ruminant Babesia spp. and their tick vectors in Switzerland was conducted. A total of 2,017 ticks were collected from sheep, goats, cattle, and wild ruminants (deer, roe deer, and chamois) in southern parts of Switzerland and identified morphologically. The vast majority of the ticks (99.2%) were Ixodes ricinus, but 14 ticks from sheep and goats were identified as Dermacentor marginatus and two ticks from wild ruminants were identified as Hemaphysalis punctata. PCR analyses of 700 ticks revealed the presence of Babesia divergens (n = 6), Babesia sp. genotype EU1 (n = 14), and B. major (n = 2), whose suggested occurrence was confirmed in this study by molecular analysis, and the presence of novel Babesia sp. genotype CH1 (n = 4), which is closely related to B. odocoilei and to Babesia sp. genotype RD61 reported from North America. The identification of B. divergens and B. major in ticks collected from wild ruminants cast doubt on the postulated strict host specificity of these bovine Babesia species. Furthermore, the zoonotic Babesia sp. genotype EU1 was detected in ticks collected from domestic animals but was obtained predominantly from ticks collected from wild ruminants. More than one tick containing DNA of different Babesia spp. were collected from two red deer. Hence, the role of these game animals as reservoir hosts of Babesia spp. seems to be important but requires further investigation.  相似文献   

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