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1.
为研究太子河大型底栖动物摄食功能群对河岸带土地利用类型的响应关系,于2012年5月对太子河流域底栖动物和水环境因子和土地利用类型进行野外调查及数据分析。结果表明:1)太子河流域底栖动物群落在4种不同土地利用类型内具有极显著差异,平均丰度、Shannon-Wiener多样性指数和Pielou均匀度指数在森林用地中最高,分别为8.86、0.73和0.94,平均密度在森林耕作用地中最高(782.75个/m2),除食碎屑者功能群(S),其他摄食功能群在不同土地利用类型内无差异(P > 0.05)。2)太子河土地利用类型与水环境因子之间的Pearson分析表明,森林用地与EC、TDS、TN、NH3-N、CODMn之间呈显著负相关性,与DO、IOS之间呈显著正相关性;耕地与DO和IOS之间呈显著负相关性;城镇用地与EC、TDS和TN之间呈正相关性。3)太子河土地利用类型与底栖动物功能群之间的Spearman分析表明森林用地与食碎屑者(S)、刮食者(SC)和收集者(GC)呈正相关性。耕地与食碎屑者(S)、滤食者(FC)之间呈负相关性,城镇用地与刮食者(SC)和收集者(GC)之间呈显著负相关性。4)底栖动物功能群和水环境因子之间的典范对应分析表明,食碎屑者(S)功能群主要受底质指数(IOS)驱动,其他功能群与环境因子之间无相关性。因此,水环境因子和底栖动物群落参数比摄食功能群更能反映人类活动对土地利用的改变,水环境和底栖动物群落研究可为河岸带土地利用保护提供理论依据。  相似文献   

2.
高欣  丁森  张远  马淑芹  刘思思  孟伟 《生态学报》2015,35(21):7198-7206
河流生态系统的退化是多空间尺度环境因子作用的结果。探讨不同尺度环境因子及水生生物之间的作用关系,识别影响水生生物群落完整性的尺度问题,是有效开展水生生物保护的基础。基于2009年对太子河流域15个样点的鱼类、河岸带栖息地质量评价,结合遥感影像解译的太子河流域土地利用情况(包括流域尺度和河段尺度),研究鱼类完整性指数(F-IBI)与两种尺度土地利用、栖息地质量参数之间的关系。结果表明太子河上游地区河岸栖息地质量较好,下游地区由于农业用地、城镇用地比例的增加河岸栖息地质量明显下降。F-IBI与自然用地比例呈正相关,与农业、城镇用地比例呈负相关。农业用地对F-IBI的影响体现在流域尺度,而城镇用地在两种尺度上都存在显著影响。相比于农业用地,城镇用地相同比例的增加会导致F-IBI更快的下降。底质、水质状况、人类活动强度是显著影响F-IBI的栖息地质量评价参数。3项参数均随农业和城镇用地比例增加而降低,农业用地主要在流域尺度上对3项参数产生影响,城镇用地主要影响底质和水质状况2项参数,而在两种尺度上的影响相差不大。  相似文献   

3.
韩洁  宋蒙蒙  张杰  殷旭旺  徐宗学  张远 《生态学报》2019,39(6):2013-2020
在生态系统中特定的环境变量组合对应着特定的物种群落结构。栖息地环境的不同,大型底栖动物的分布和所表现出的生物学特征也存在差异。在浑河流域选取22个点位进行调查研究,通过对大型底栖动物进行功能群分类并结合生物性状分析(BTA, Biological Traits Analysis)对浑河流域不同大型底栖动物摄食功能群对栖息地生境的选择适应性进行研究。研究结果表明:捕食者功能群主要以毛翅目为主;直接收集者功能群主要以双翅目为主;刮食者功能群主要以基眼目为主;过滤收集者多为颤蚓目。浑河流域不同大型底栖动物摄食功能群存在明显的空间差异,典范对应分析结果显示:影响捕食者功能群的驱动因子是流速,直接收集者功能群的驱动因子是IOS指数,刮者功能群的驱动因子是溶解氧;过滤收集者功能群的驱动因子是溶解氧和电导率。生物性状分析结果显示:捕食者功能群身体上附有一层硬壳保护,可在水体中自由活动,多分布流速较快,底质复杂的小鹅卵石、圆石的底质中;直接收集者只有头壳具有较厚的甲壳质壁,头部口器不能直接摄食,所以多以微粒有机颗粒为主,分布在石块、部分圆石以及部分粗砂中;刮食者多以藻类、菌类等为食,足腺多分泌粘液,多粘附在较深流速缓慢,底质多为细沙粗粒,食物来源充足的水体;过滤收集者喜栖于淤泥底质中,吸食淤泥或过滤有机碎屑,故多分布于淤泥与细沙底质中。  相似文献   

4.
长江口及邻近海域高营养层次生物群落功能群及其变化   总被引:6,自引:0,他引:6  
通过对2006年6、8和10月在长江口及邻近海域3次调查采集样品的分析,对该水域的高营养层次生物群落的功能群组成及其变化进行了研究.结果表明:长江口及邻近海域高营养层次生物群落包括鱼食性、蟹食性、虾食性、底栖动物食性、浮游生物食性和广食性6个功能群.由于受海洋环境变化以及鱼类洄游活动的影响,各月份长江口及邻近海域高营养层次生物群落的组成及营养级都有较大的变化.6月高营养层次以鱼类、毛虾类和蟹类为主,以浮游生物食性功能群为主要功能群,营养级最低,为3.06;8月高营养层次以鱼类为主,虾食性功能群为主要功能群,营养级达到最高,为3.78;10月高营养层次虽仍以鱼类为主,虾蟹类比例增大,功能群以浮游动物食性和底栖动物食性功能群为主,营养级为3.58.  相似文献   

5.
不同尺度因子对滦河流域大型底栖无脊椎动物群落的影响   总被引:1,自引:0,他引:1  
通过2011年滦河流域38个河段大型底栖无脊椎动物采集,探讨了河段尺度和流域尺度环境因子对大型底栖无脊椎动物分布的影响。其中,河段尺度因子包括水体/底质特征、河岸带特征和水质,流域尺度因子包括采样位置、流域土地利用结构和缓冲区土地利用结构。RDA(冗余分析)结果表明,河段尺度影响大型底栖无脊椎动物分布的关键因子为:细粒物质比例、河岸带植被盖度、河岸带人类干扰程度、河岸带农田比例、水面宽度和河道改造程度,总解释量为42%;流域尺度影响大型底栖无脊椎动物分布的关键因子为:纬度、海拔、流域内耕地面积百分比和流域面积,总解释量为32%。研究结果表明,河段尺度因子比流域尺度因子对于指示大型底栖无脊椎动物分布更为重要,在环境因子监测中应给以更多的重视。  相似文献   

6.
应用样方法研究了辽宁太子河河岸带草本物种组成特征。结果表明:1)太子河河岸带共有草本植物207 种,隶属于36 科125 属。其中菊科物种最多,水蓼出现的频率最高;2)太子河河岸带草本植物属级区系组成丰富,以温带分布区类型为主,其次为热带分布区类型;3)所有物种中,水生或湿生植物120 种,旱生或中生植物87 种,分别占总物种数的58.0%和42.0%;4)根据物种在样方中出现与否,将样点分为2 类;一类分布于高海拔地区,物种以旱生或中生植物为主,物种数多,而另一类分布于低海拔地区,物种以水生或湿生植物为主,物种数较少;5)河岸带草本物种中有杂草和人类伴生种出现,且频率较高,表明太子河河岸带受到人类活动,如农田开发、挖沙和人类居住的影响。  相似文献   

7.
为揭示七星列岛省级海洋特别保护区鱼类群落现状, 于2014年秋季(11月)和2015年春季(5月)进行底拖网调查。利用生态位测度、非度量多维标度排序和等级聚类等方法对该海域鱼类功能群组成及生态位特征进行了研究。结果表明, 该区鱼类可划分为浮游生物食性、底栖动物食性、游泳动物食性、浮游生物/底栖动物食性、底栖动物/游泳动物食性和杂食性6个功能群。浮游生物食性、底栖动物食性和底栖动物/游泳动物食性功能群是秋季优势功能群, 浮游生物食性、游泳动物食性和杂食性是春季优势功能群。秋季, 主要鱼类生态位宽度值变化范围为0.28-3.84, 其中龙头鱼(Harpodon nehereus)、六指马鲅(Polydactylus sexfilis)、赤鼻棱鳀(Thrissa kammalensis)、红狼牙鰕虎鱼(Odontamblyopus rubicundus)、海鳗(Muraenesox cinereus)、尖头黄鳍牙鱼或(Chrysochir aureus)和叫姑鱼(Johnius belengerii)的生态位宽度值较高; 春季生态位宽度值变化范围为0.36-3.16, 其中带鱼(Trichiurus lepturus)、日本鳀(Engraulis japonicus)、蓝圆鲹(Decapterus maruadsi)、刺鲳(Psenopsis anomala)、龙头鱼和镰鲳(Pampus echinogaster)的生态位宽度值较高。秋季, 主要鱼类生态位重叠值在0-0.94之间波动; 春季, 主要鱼类生态位重叠值在0-0.92之间波动。以丰度数据平方根为基础, 利用非度量多维标度排序和等级聚类分析, 主要鱼类秋季可以分为4组, 而春季可以分为3组。上述结果表明, 保护区鱼类群落的营养结构和空间结构较好。  相似文献   

8.
为了解互花米草入侵对红树林湿地生态系统底栖甲壳动物和鱼类的影响,本研究利用地笼方式于2020年8月、2021年1月和4月对福建漳江口2个原生红树林样地(白骨壤和秋茄)、2个互花米草入侵样地以及1个光滩样地的底栖甲壳动物和鱼类进行采样调查。采用相对重要性指数、Shannon多样性指数、Pielou均匀度指数和Margalef丰富度指数分析底栖甲壳动物和鱼类的优势种及物种多样性,统计其功能群,并计算其生态位宽度和生态位重叠指数。结果表明: 3个季节共采集到底栖甲壳动物和鱼类种类37种,隶属于2门2纲8目17科,其中大多数为暖水性和广盐性物种,且以肉食性和杂食性功能群为主。双因素方差分析和非度量多维尺度分析结果表明,相比光滩,互花米草入侵后,底栖甲壳动物和鱼类的群落多样性指数变化不显著,但功能群发生了显著变化,浮游生物食性功能群以及肉食性和植食性功能群物种均有一定程度的增加。相比红树林样地,互花米草样地内底栖甲壳动物和鱼类物种丰富度更高。优势物种的时空生态位宽度变化范围在0~1.4186,其中棱鮻最高(1.4186),其次是中华乌塘鳢(1.0168)、刀额新对虾(0.9469)、脊尾白虾(0.8922)。  相似文献   

9.
莱州湾鱼类群落同功能种团的季节变化   总被引:4,自引:0,他引:4  
利用2011年5月、8月、10月和12月底拖网调查数据,对莱州湾海域鱼类同功能种团特征及其季节变化进行了研究。全年调查共渔获鱼类49种,全部为硬骨鱼类。根据鱼类的摄食习性,调查海域鱼类可划分为浮游动物食性种团、浮游动物/底栖动物食性种团、底栖动物食性种团、底栖动物/游泳动物食性种团、游泳动物食性种团、杂食性种团和碎屑食性种团共7个同功能种团,其中底栖动物食性种团种类数最多(14种),底栖动物/游泳动物食性种团次之(12种)。碎屑食性种团生物量在全年处于第一优势地位,占32.8%;其次为浮游动物食性种团,占31.6%;再次为底栖动物/游泳动物食性种团,占25.0%。同功能种团多样性(HFD)和种类多样性(Hs)季节变化趋势相同,均在夏季达到最高值,冬季达到最低值;两者关系使用指数方程拟合效果最佳。浮游动物食性种团平均营养级为3.71、浮游动物/底栖动物食性种团为3.83、底栖动物食性种团为3.43、底栖动物/游泳动物食性种团为3.75、游泳动物食性种团为3.86、杂食性种团为3.73、碎屑食性种团为3.34。与20世纪80年代、90年代调查结果相比,目前莱州湾碎屑食性种团比例明显上升,游泳动物食性种团比例大幅下;底栖动物食性种团和游泳动物食性种团的平均营养级明显下降,碎屑食性种团平均营养级有所上升。  相似文献   

10.
和克俭  刘虹  丁佼  黄晓霞  刘琦  张琦 《生态学报》2021,41(23):9525-9535
研究土地利用对大型底栖动物群落的影响,对流域土地利用规划修编和河流生态修复等有重要意义。以红河上游的把边江流域为研究区,调查大型底栖动物群落现状,计算37个样点上游集水区土地利用组分、配置、多样性和水文距离4个方面20个土地利用指标,分析不同土地利用方式对大型底栖动物群落的影响。本次调查共鉴定出25个大型底栖动物分类单元,其中水生昆虫最多,占分类单元总数的72%;摄食功能群以捕食者(PR)、刮食者(SC)和直接收集者(GC)为主。把边江流域城镇用地和林地对大型底栖动物群落的影响占主导地位,而耕地对大型底栖动物群落的影响较小。影响把边江流域大型底栖动物群落的关键土地利用指标为城镇用地面积比(3PLA)、城镇用地最大斑块指数(3LPI)、城镇用地聚合指数(3AI)、城镇用地水流长度(3FLOW)、林地最大斑块指数(1LPI)和林地形状指数(1LSI)。土地利用组分、配置和水文距离是影响把边江流域大型底栖动物群落的主要方面,而土地利用多样性对大型底栖动物群落的影响较小。大型底栖动物物种密度和物种多样性与3PLA、3LPI、3AI、3FLOW和1LSI呈负相关,与1LPI呈正相关。1LPI与浮游目(如小蜉科、扁蜉科)为代表的清洁物种呈现较明显的正相关关系。城镇用地指标与SC和SH(撕食者)密度具有显著的负相关关系,与GC密度有较弱的正相关关系,而与其他功能群没有明显的相关关系。SC和SH对水质和环境条件敏感,而GC对人类干扰耐受性较强。1LPI与SC和FC(滤食收集者密度)正相关,而与PR和GC密度负相关。SC和FC对生境的完整性要求较高,而GC和PR对人为干扰和较为破碎的生境更为适应。一方面,随着城镇用地的规模、边界复杂性和聚集程度增加,研究区大型底栖动物密度和多样性降低;另一方面,随着林地完整性降低,大型底栖动物物种均匀度降低。土地利用与大型底栖动物物种多样性和功能群多样性的关系不完全一致,1LSI和3FLOW与物种多样性负相关,而与功能群多样性呈正相关关系,土地利用对物种-功能群-群落不同尺度上的影响差异还需要更深入的研究。  相似文献   

11.
12.
《环境昆虫学报》2014,(5):790-804
综述了白蚁螱客的主要种类、共生关系及相关机制的研究进展。白蚁螱客中,已报道的动物种类达170种。在与动物的共生关系中存在偏利共生(宾主共栖和异种共栖)、互利共生和无关共生三种;在与微生物的共生关系中,存在与内生菌(原生动物、细菌、真菌和放线菌)和外生菌(蚁巢伞菌等)间的互利关系。指出了白蚁与螱客研究中存在的问题,给出了解决方案,并提出了今后可能的研究热点或方向,为白蚁的综合利用(如纤维素酶)及今后研究物种间的协同进化提供了基础资料。  相似文献   

13.
New sulfur derivatives of phosphoramidite ligands were synthesized and the impact of the sulfur unit on the spectroscopic properties of their rhodium and iridium complexes was investigated. The new ligands Bn2NPSCH2CH2Sa(P-Sa) (Bn = benzyl, 4), Bn2NPSCHCHSa(CH2)3CaH2(P-Sa)(Ca-Sa) (6) and Bn2NP(4-XC6H4OMe)2 (X = S, 7a; X = O, 7b) were converted to the rhodium and iridium complexes trans-[Rh(CO)Cl(L)2] (L = 4, 6, 7), [RhCl(COD)(L)] (L = 4, 6, 7), [IrCl(COD)(7a)] and [IrCl2Cp∗(6)]. For comparison, some phosphoramidite complexes of these formulations also were synthesized. The new metal complexes were spectroscopically analyzed. For the carbonyl complexes, the νCO IR stretching frequencies were lower than for the corresponding phosphite and phosphoramidite ligands. The 1JPRh coupling constants for the rhodium complexes with the new ligands were also smaller than for the respective phosphoramidite and phosphite complexes. Finally, the 1JPSe coupling constants of the selenides of the new ligands were lower than those of the phosphoramidite ligands but higher than for PPh3. The spectroscopic data reveal that the new thio ligands 4, 6 and 7a are more electron donating than phosphites and phosphoramidites but less electron donating than PPh3.  相似文献   

14.
Astrocytes transport the monocarboxylate acetate, but synaptosomes do not. The reason for this is unknown, because both preparations express monocarboxylate transporters (MCT). The transport and metabolism of lactate, another monocarboxylate, was examined in these two preparations, and the results were compared to those for acetate. Lactate transport is more rapid in astrocytes than in synaptosomes, but of lower affinity (Kms of 17 and 4 mM, respectively). Lactate (0.2 mM) is metabolized to CO2 more rapidly in synaptosomes than in astrocytes (rates of 0.37 and 0.07 nmol x mg protein(-1) x min(-1), respectively). The reason for this is unclear, but cellular differences in lactate dehydrogenase isotype expression may be involved. Acetate is metabolized to CO2 more rapidly in astrocytes than in synaptosomes (rates of 0.43 and 0.02 nmol x mg protein(-1) x min(-1), respectively). This is likely due to cellular differences in the expression of monocarboxylate transporter subtypes.  相似文献   

15.
The first and second sessions of the Workshop focussed on the basics of ultrasound and infrasound, their applications in both industry and medicine, and metrology and protection standards for ultrasound applications.  相似文献   

16.
Cytoskeleton and mitochondrial morphology and function   总被引:10,自引:0,他引:10  
It has been well established that the cytoskeleton is an essential modulator of cell morphology and motility, intracytoplasmic transport and mitosis, however cytoskeletal linkage to the organelles has not been unequivocally demonstrated. Indeed, cytoskeleton appears to be essential in determining and modulating gene phenotype as a function of cellular environment. According to recent studies, the organization of the cytoskeleton network together with associated protein(s) could be essential in regulating mitochondrial function and particularly the permeability of the mitochondrial outer membrane to ADP. The aim of this chapter is to summarize the main properties of the cytoskeletal environment of mitochondria and the possible role(s) of this network in mitochondrial function in myocytes.  相似文献   

17.
To elucidate accumulation of minerals in human iliac arteries with aging, the content of minerals was analyzed by inductively coupled plasma atomic emission spectrometry. Bilateral common, internal, and external iliac arteries of 16 men and 8 women, ranging ages from 65 to 93 yr, were examined. It was found that an extremely high accumulation of calcium and phosphorus occurred in the common iliac artery at old age, being higher than that of the internal and external iliac arteries. It should be noted that the accumulation of calcium and phosphorus is the highest in the common iliac artery among the human arteries examined to date. Regarding sexual differences, the content of calcium and phosphorus in the common and internal iliac arteries was higher in women than in men, whereas their content in the external iliac artery was lower in women than in men.  相似文献   

18.
以人胎盘脐带组织为材料,提取组织总RNA,用netRTPCR方法合成人血管能抑素cDNA基因,将该cDNA克隆进pSP72载体获得重组质粒pSP72C, DNA序列分析结果与预期序列一致。用BamHⅠ和NdeⅠ双酶切,切下pSP72C上的血管能抑素cDNA,插入pET3c载体的相应位点获得重组表达质粒pETC, 转化E. coli BL21(DE3), SDSPAGE分析显示:在IPTG诱导下,血管能抑素基因获得了高效表达,表达量约占菌体总蛋白的 27.9 %,主要以包涵体形式存在。包涵体经过洗涤、裂解、蛋白复性以及Sephadex G75凝胶过滤层析等步骤后,获得了纯度达91.4 %的人血管能抑素。CAM实验证明10 μg纯化蛋白就能显著抑制鸡胚新生血管生成。  相似文献   

19.
To examine the hypothesis that foot-strike hemolysis alters vascular volumes and selected hematological properties is trained athletes, we have measured total blood volume (TBV), red cell volume (RCV) and plasma volume (PV) in cyclists (n = 21) and runners (n = 17) and compared them to those of untrained controls (n = 20). TBV (ml x kg(-1)) was calculated as the sum of RCV (ml x kg(-1)) and PV (ml x kg(-1)) obtained using 51Cr and 125I-labelled albumin, respectively. Hematological assessment was carried out using a Coulter counter. Peak aerobic power (VO2peak) was measured during progressive exercise to fatigue using both cycle and treadmill ergometry. RCV was 15% higher (P < 0.05) in male cyclists [35.4 (1.0), mean (SE); n = 12] and runners [35.3 (0.98); n = 9] compared to the controls [30.7 (0.92); n = 12]. Similar differences existed between the female cyclists [28.2 (2.1); n = 9] and runners [28.4 (1.0); n = 8] compared to the untrained controls [24.9 (1.4); n = 8]. For the male athletes, PV was between 19% (cyclists) and 28% (runners) higher (P < 0.05) in the trained athletes compared to the untrained controls. The differences in PV between the female groups were not significant. Although the males had a higher (P < 0.05) TBV, RCV and PV than the females, no differences between cyclists and runners were found for either gender. Mean cell volume was not different between the athletic groups. VO2peak (ml x kg(-1) x min(-1)) was higher (P < 0.05) in both male [68.4 (1.5)] and female [54.8 (2.1)] runners when compared to the untrained males [47.1 (1.0)] and females [40.5 (2.1)]. Although differences existed between the genders in VO2peak for both cyclists and runners, no differences were found between the athletic groups within a gender. Since the vascular volumes were not different between cyclists and runners for either the males or females, foot-strike hemolysis would not appear to have an effect on that parameter. The significant correlations (P < 0.05) found between VO2peak and RCV (r = 0.64 and 0.64) and TBV (r = 0.82 and 0.63) for the males and females, respectively, suggests a role for the vascular system in realizing a high aerobic power.  相似文献   

20.
D-Xylitol is found in low content as a natural constituent of many fruits and vegetables. It is a five-carbon sugar polyol and has been used as a food additive and sweetening agent to replace sucrose, especially for non-insulin dependent diabetics. It has multiple beneficial health effects, such as the prevention of dental caries, and acute otitis media. In industry, it has been produced by chemical reduction of D-xylose mainly from photosynthetic biomass hydrolysates. As an alternative method of chemical reduction, biosynthesis of D-xylitol has been focused on the metabolically engineered Saccharomyces cerevisiae and Candida strains. In order to detect D-xylitol in the production processes, several detection methods have been established, such as gas chromatography (GC)-based methods, high performance liquid chromatography (HPLC)-based methods, LC-MS methods, and capillary electrophoresis methods (CE). The advantages and disadvantages of these methods are compared in this review.  相似文献   

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