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1.
研究了酸性水对椭圆萝卜螺和铜锈环棱螺等淡水螺类存活、生长及繁殖的影响。结果表明,椭圆萝卜螺对低pH值的耐受能力,96小时LC_(50)值为pH3.96。pH值低于5.0时,淡水肺螺类产的卵袋数量较少,卵孵化时间较长,幼螺生长较缓慢。铜锈环棱螺仔螺在低pH(对照组)下生长到第35和45天时,其体长生长率分别为1.21和1.07%,而pH5.0组则仅有0.18和0.29%。pH5.5对淡水肺螺类无明显影响,pH3.0则不能生存。  相似文献   

2.
水生生态系统中,pH是重要的非生物因子之一.pH可以通过影响水生生物的存活和繁殖,进而影响其在水体中的分布和多度,最终决定水生群落的物种组成和丰富度[1].  相似文献   

3.
不同盐度、pH条件下氨氮对管角螺稚贝毒性影响   总被引:6,自引:1,他引:5  
在水温28.5℃,采用实验生态学方法研究了不同盐度、pH条件下氨氮对管角螺(Hemifusus tuba)稚贝[壳高(11.3±0.11)mm,n=30]毒性的影响。结果表明,(1)盐度对氨氮的毒性有较大影响,随着盐度的降低,氨氮在水体中的毒性增强;盐度为16、19、23和28,总氨氮对稚贝的96h半数致死浓度(96hLC50)分别为36.5、43.7、52.6和58.8mg/L,安全浓度(SC)为3.7、4.4、5.3和5.9mg/L。(2)氨氮在水体中的毒性随pH的升高而增强,pH为7.6、8.0、8.4和8.8时,总氨氮对稚贝的96hLC50依次为58.3、54.5、50.6和20.2mg/L,对应的SC依次为5.8、5.5、5.1和2.0mg/L。氨氮在pH8.8时对稚贝的96hLC50急剧下降,其毒性是在pH7.6时的2.9倍。  相似文献   

4.
原生动物与环境保护   总被引:1,自引:0,他引:1  
原生动物是动物界里最原始、最低等的动物,身体由一个细胞组成,最大的多核变形虫约有2毫米,最小的海产纤毛虫只有1-1.5微米,一般都在50-100微米左右。种类多、分布广,约有3万多种,除一部分寄生生活外,大多生活于水体中营自由生活,与水体中的其他水生生物一起组成水生生物系统。随着工农业的发展,大量未经处理的废水和其他污染物不断进入水体,对水生态系统造成强大压力。在水环境保护工作中,越来越发现原生动物在水体自净,水体生物监测中占有重要位置。原生动物在水体自净和污水处理中的作用天然水体受到污染以后,由于自然界的物理、化学和生物等作用,水体会得到净化,生  相似文献   

5.
本文通过酸雨对翅荚木种子萌发生理影响的简易模拟试验,结果表明:酸雨对种子发芽率和胚生长的影响。pH4以上较小,pH3以下则产生明显的抑制效应。酸雨对种子透性的变化,随酸雨pH值的降低而增大。酸雨与酶活性的关系是pH4以上的酸雨对抗坏血酸氧化酶活性表现促进效应,pH3以下的酸雨则产生抑制作用。唯多酚氧化酶的活性,随酸雨的pH值降低而减少。呼吸作用与抗坏血酸氧化酶的活性有着相似的变化规律,pH5的呈现促进作用,pH4以下则随pH值下降而减弱。种子萌发时可溶性糖、粗脂肪和蛋白质的含量也随酸雨的pH值降低而减少。  相似文献   

6.
中国科学院水生生物研究所(以下简称“水生所”)是研究内陆水体生命过程、生态环境保护与生物资源利用的综合性学术机构。自20世纪50年代开始,水生所科研人员率先有计划地针对全国主要水体开展了实地科学考察,产生了大量的水生生物原始生态学数据;随着显微拍照和测序技术的进步,调查还产生了各种浮游生物显微照片和大量的遗传数据。这些数据为水生态监测服务系统和数据库的构建提供了数据支持,有助于推进水生生物学研究的发展。此外,面向国家在水环境保护、渔业可持续发展方面的重大战略需求,中国科学院水生生物研究所科学数据中心(以下简称水生所科学数据中心)(http://sdb.ihb.ac.cn/)聚焦科学数据标准规范、安全可控和开放共享,对上述科学数据进行收集保存、汇交整合、分级管理和分析挖掘,以期为生态环境保护与生物资源保护利用等领域的基础性、战略性和前瞻性的科学研究和技术创新服务。  相似文献   

7.
模拟酸雨对蚕豆植物生长的影响   总被引:24,自引:2,他引:22  
模拟酸雨对盆栽蚕豆(Vicai faba)植物生长的影响表明,它对出苗率影响不大,但当它的pH为2.0时则对蚕豆初期的出苗速率有一定的促进作用。在苗出土后,酸雨的作用由促进转变为抑制,并随酸雨pH值的降低而增大,致使株高、叶片生长和叶绿素含量减少,酸雨对叶片的伤害幼叶较老叶更容易。  相似文献   

8.
LY-04和WSQIF是由华中师范大学农药所合成的两种新型有机磷农药,LY-04属于α-氧代膦酸衍生物,WSQIF属于芳氧基乙酰氧基烃基膦酸脂。选用斜生栅藻(ScenedesmusobliquusKütz.)作为实验生物,通过显微计数测定藻细胞的密度以计算LY-04和WSQIF对斜生栅藻24h、48h、72h、96h的半效应抑制浓度(EC50),研究其对斜生栅藻的毒性效应。结果表明:以丙酮为溶剂时,每隔24h取样,测得LY-04对斜生栅藻的48h、72h、96h的EC50值分别为2942.5mg/L、239.7mg/L和65.0mg/L,而WSQIF的24h、48h、72h、96h的EC50值分别为15.9mg/L、53.0mg/L、98.0mg/L和28.8mg/L。LY-04和WSQIF分别作为杀虫剂和除草剂而研制,经活体研究表明,LY-04具有较强的杀虫活性,WSQIF则具有很强的除草活性,所得EC50值基本符合设计结果。根据毒性分级标准,LY-04和WSQIF的EC50值远大于3mg/L,其对非靶生物中的水生藻类都属于低毒,可推广应用。  相似文献   

9.
五种水蛭对不同P^H值的生物效应   总被引:1,自引:0,他引:1  
本文论述了使用常规试验方法研究5种水蛭:宽身舌蛭(Glossiphonia lata)、八目石蛭(Erpobdella octoculata)、光润金线蛭(Whitmania laevis)、尖细金线蛭(Whitmania acranulata)和日本医蛭(Hirudo nipponia)对12个pH值的24—96小时急性生物效应。结果表明:稻田3个种(尖细金线蛭,光润金线蛭和日本医蛭)均较湖泊近岸2个种(八目石蛭和宽身舌蛭)对pH值的变化要敏感,其中尖细金线蛭最敏感(pH6.0—7.2),八目石蛭的忍耐限度最宽(pH4.0—10.5);当pH值在9.5时,稻田3种水蛭的死亡率在40%以上,其中日本医蛭高达70%;当pH值在3.0时,湖泊近岸2种在24小时内全部死亡,日本医蛭仅死亡10%。日本医蛭是华中农村地区一种主要吸血蛭类,生石灰是一种从稻田消灭蛭类的有效手段,然而水的pH值必须不低于8.6。  相似文献   

10.
探讨了利用典型沉水植物密齿苦草修复城市水体的技术,评价了生态浮岛技术对城市水体的净化作用,探索了滤食性动物对水体的净化作用。研究表明,沉水植物恢复、生态浮岛和滤食性动物吸收转化技术可用于修复城市水体,恢复水体的自净能力,逐步增加水生生态系统的生物多样性,完善水生生态系统的结构及其生态功能。  相似文献   

11.
Response of Soybean Seed Germination to Cadmium and Acid Rain   总被引:2,自引:0,他引:2  
Cadmium (Cd) pollution and acid rain are the main environmental issues, and they often occur in the same agricultural region. Nevertheless, up to now, little information on the combined pollution of Cd(2+) and acid rain action on crops were presented. Here, we investigated the combined effect of Cd(2+) and acid rain on the seed germination of soybean. The results indicated that the single treatment with the low level of Cd(2+) (0.18, 1.0, 3.0?mg?L(-1)) or acid rain (pH ≥3.0) could not affect the seed germination of soybean, which was resulted in the increased activities of peroxidase and catalase. The single treatment with the high concentration of Cd(2+) (>6?mg?L(-1)) or acid rain at pH?2.5 decreased the activities of peroxidase and catalase, damaged the cell membrane and then decreased the seed germination of soybean. Meanwhile, the same toxic effect was observed in the combined treatment with Cd(2+) and acid rain, and the combined treatment had more toxic effect than the single treatment with Cd(2+) or acid rain. Thus, the combined pollution of Cd(2+) and acid rain had more potential threat to the seed germination of soybean than the single pollution of Cd(2+) or acid rain.  相似文献   

12.
酸雨对植物—害虫—天敌系统的作用   总被引:3,自引:0,他引:3  
综述了酸雨对植物—害虫—天敌系统的影响和酸雨对害虫的作用机制 ,探讨了模拟酸雨与自然酸雨对生态系统的不同作用 ,并展望了进一步研究和发展的方向。  相似文献   

13.
At present, acid rain has become one of the top ten global environmental issues. Acid rain causes slower growth, injury, or decline of forests. Some dramatic effects on forests have been observed in south China since the late 1970s and the situation is deteriorating. We carried out a comparative proteomic analysis on Pinus massoniana Lamb, a staple tree species widely distributed in middle and south China to gain a better understanding of tree response to acid rain at molecular level. Two-year-old P. massoniana saplings were treated with simulated AR (SiAR) or control solution, respectively, for 8 months. The changes in total protein profile of P. massoniana leaves were studied using two-dimensional differential gel electrophoresis (2D-DIGE). Among the total protein spots reproducibly detected on each gel, 65 spots representing 28 proteins were identified to be differentially regulated. These proteins were annotated in various biological functions, such as photosynthesis and energy metabolism, secondary metabolism, protein stability, amino acid and nitrogen metabolism and defense. Down-regulation of four key enzymes in the Calvin cycle identified that biomass loss by SiAR was mainly due to the inhibition of carbon fixation. Primary energy metabolisms involved in sucrose biosynthesis, glycolytic pathway and Krebs cycle, etc., were also disturbed after SiAR treatment. Specifically, most of up-regulated proteins were related to secondary metabolism, protein stability and defense, suggesting that in response to SiAR stress, plants started a variety of metabolic pathways to prevent cells from damage. Different from the herbaceous plants suffering SiAR, it revealed that secondary metabolites in P. massoniana play pivotal roles against SiAR. Protemoic techniques were demonstrated a reliable and robust tool to expand our understanding of differentially expressed proteins associated with acid rain stress on P. massoniana. Functional analysis of these proteins further revealed biochemical and physiological basis of the plant in response to acid rain and would provide strategies for breeding new acid rain tolerant tree species. To our knowledge, it is the first proteome report on the forest plant suffering long-term acid rain stress.  相似文献   

14.
The synthesis and accumulation of starch is greatly affected by environmental stress. Wheat grown in the downstream area of the Yangtze River is easily subjected to stress of waterlogging and acid rain. In order to probe the effect of waterlogging and acid rain on yield and starch characteristic, we used winter wheat cultivars of Yangmai 16 (more resistant) and Wennong 17 (relatively sensitive) to sole stress of acid rain or waterlogging and to their combinations during grain filling. The responses of grain yield, the physiochemical properties and morphology of starch granules in endosperm to the stresses were investigated. Compared with CT (control), grain yield in Wennong 17 were significantly decreased by both pH 4.0 acid rain and pH 2.5 acid rain, while in Yangmai 16 only by pH 2.5 acid rain. Waterlogging combined with acid rain significantly reduced grain weight and grain yield in both wheat cultivars. Acid rain, waterlogging and their combination depressed activities of ADP glucose pyrophosphorylase and soluble starch synthase (SSS) in grains of both cultivars. Acid rain and waterlogging damaged endosperm cell structure and caused abnormal starch granules. Starch granules at maturity became fragile and failed to keep in shape and some granules were even totally submerged in the protein matrix and other tissue under acid rain and waterlogging. Content of amylopectin and amylopectin/amylose ratio was also decreased, while content of amylose was increased under acid rain and waterlogging. As a result, swelling power and most viscosity parameters decreased, while the pasting temperature increased in both cultivars due to stresses. In sum, acid rain and waterlogging and their combination damaged cell structure and depressed synthesis of amylopectin, and led to the formation of abnormal fragile starch granules, and finally reduced grain weight and then yield, and deteriorated starch quality.  相似文献   

15.
本文指出了酸雨对翅荚木细胞透性、pH值、等电点、耐酸力均有显著的影响。其影响是随酸雨pH值的下降和浸没时间的延长而增加。发芽种子的抗坏血酸氧化酶、多酚氧化酶的活性,呼吸强度和可溶性糖、粗脂肪和蛋白质的含量,也是随酸雨pH值的下降而降低。叶绿素总量、叶绿素a,b和a/b的比值,pH 5处理与对照无差异,低于pH4以下的处理叶绿素a含量则大幅度减少。叶绿素b含量则较稳定。根系的活力也是随酸雨pH值下降而急剧减少。酸雨对翅荚木种子的发芽率、出苗率及胚和幼苗的生长,都表现有不同程度的抑制效应,酸雨对叶片的伤害,也是随酸雨pH值的降低、喷洒次数的增多和浸没时间的延长而加重。  相似文献   

16.
酸雨引起森林生态系统钙流失研究进展   总被引:7,自引:0,他引:7  
酸雨作为一个全球性环境问题,随着我国经济的快速发展,其危害也日益严重。诸多长期观测研究认为酸雨导致森林生态系统营养流失,特别是Ca的流失是酸雨导致森林衰退的一个重要原因。长期酸雨影响下,土壤中的Ca大量流失,在红壤等酸性土壤中表现得尤为严重;此外酸雨也会直接淋溶出植物叶片中的Ca,造成林冠中Ca不同程度的淋溶流失,并可能造成叶片Ca含量下降。且酸雨会导致叶片细胞内Ca稳态的失衡,影响植物的正常生理响应。对于整个森林生态系统而言,酸雨改变了生态系统中Ca生物地球化学循环的特征,大量的Ca从森林生态系统中以地表径流的形式流出系统,导致可利用Ca库的下降和周转速率的上升。酸雨对森林土壤、植物及生态系统各层面中的Ca均造成了长期广泛的影响,深入研究其影响程度与植物的应对机制,对我国酸雨危害区的酸雨防治和森林保育具有重大意义。  相似文献   

17.
酸雨是中国重要的环境问题,为研究酸雨对小麦籽粒品质的可能影响,以小麦品种扬麦15和汶农17为材料开展盆栽试验,研究了不同酸度(pH2.5、p H4.0和p H5.6)酸雨对小麦花后氮硫代谢关键酶活性和籽粒蛋白质含量及组分的影响。结果显示:酸雨处理抑制叶片硝酸还原酶(NR)活性,提高了扬麦15整个灌浆期及汶农17灌浆中后期叶片谷氨酰胺合成酶(GS)活性,促进了叶片蛋白的降解,降低了叶片可溶性蛋白含量。不同酸度酸雨提高了成熟期籽粒中蛋白质含量,酸度越强,增加幅度越大,籽粒中各蛋白组分含量和大部分氨基酸含量也有明显提高。酸雨提高了扬麦15叶片丝氨酸乙酰转移酶(SAT)和O-乙酰丝氨酸硫裂解酶(OAS-TL)活性,但对汶农17硫代谢关键酶活性影响较小,酸雨处理还提高了籽粒中二硫键和含硫氨基酸含量。可见酸雨对小麦氮硫代谢有不同程度影响,进而影响了小麦籽粒蛋白质含量和组成,酸度越强影响越大,但不同品种对酸雨响应有一定差异。  相似文献   

18.
19.
王楠  潘小承  白尚斌 《生态学报》2020,40(10):3420-3430
酸沉降造成的土壤持续酸化对毛竹林生态系统碳循环具有重要的影响,为量化酸沉降我国亚热带毛竹林土壤的影响,于2016年在浙江省杭州临安天目山国家级自然保护区毛竹林持续开展了2年野外模拟酸雨淋溶土壤实验,设置pH 4.0(T1)和pH 2.0(T2)两个模拟酸雨处理,以pH 5.8天然湖水为对照(CK),分析酸雨作用下土壤CO2排放及土壤微生物多样性的变化趋势,并明确毛竹林土壤呼吸、土壤微生物及土壤理化性质三者之间的关系。结果表明:土壤呼吸速率在酸雨作用下经过缓冲期后呈现先促进后抑制的变化,作用强度表现为:T2>T1。不同处理的土壤呼吸对温度的敏感性由高到低依次是:T2、CK、T1。PCR-DGGE分析表明,模拟酸雨改变了土壤微生物菌群结构,T2处理抑制了土壤细菌的多样性和丰富度,而T1处理对土壤真菌多样性和丰富度具有促进作用。土壤pH值、有效钾、可溶有机碳、微生物量碳、碱解氮和有效磷对土壤微生物群落结构及土壤呼吸具有显著的影响(P<0.05)。综上所述,模拟酸雨能够显著抑制毛竹林的土壤呼吸,并改变土壤微生物群落结构及多样性,这些结果为进一步研究毛竹林土壤生...  相似文献   

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