酸雨对植物生长的影响

本文综述了近些年来国内外酸雨对植物生长影响的研究概况。认为酸雨对玉米及某些品种的大豆花粉的萌发有抑制作用;酸雨对松林虫害的发生具有潜在的促进作用。还认为酸雨与干旱、酸雨与SO_2对植物的复合影响具有明显的协同效应。     

水体pH和曝气方式对藻类生长的影响

利用水族箱微宇宙研究了藻类在不同pH和曝气条件下的生长和种类变化.使用天然湖水,一组试验每天调节pH,使其分别保持在8.0、8.5、9.0和9.5;另一组试验是设定不同的曝气方式,分别为不曝气、完全曝气、昼间曝气和夜间曝气,定期测定水体叶绿素a和藻类组成.pH试验结果显示,在pH 8.0～9.5范围内,pH 8.5下藻类生长状况最好,pH 9.5下生长最差,人为改变pH使其远离8.5能够抑制藻类生长.曝气试验结果显示,曝气不能抑制水体中藻类的生长,昼间曝气甚至还有明显的促进作用.     

藻菌共培养对小球藻生长及苯酚降解的影响

工业苯酚废水无序排放会对环境造成极大危害,构建既能去除苯酚又能积累微藻生物质的藻菌组合对实现苯酚废水净化及其资源化利用具有重要意义。首先,研究了小球藻对苯酚的耐受性和降解性能;然后,构建了其与简单芽胞杆菌Bacillus simplex的共培养体系;最后,测试了藻菌比、藻菌接种浓度和苯酚浓度等对小球藻生长及苯酚降解的影响。结果表明:小球藻能耐受400 mg·L~(-1)的苯酚,但其对100～600 mg·L~(-1)苯酚的降解率仅为1.21%～11.66%;对于藻菌共培养体系,在固定小球藻接种浓度为0.2 g·L~(-1)、藻菌比为1∶4～4∶1条件下,3～5 d完全降解了400 mg·L~(-1)的苯酚,小球藻叶绿素(a+b)含量较单藻组增加了0.14～2.21倍,且随着藻菌比降低,苯酚降解效率及小球藻生物量逐步提高;在固定藻菌比为1∶1、小球藻初始接种浓度为0.05～0.4 g·L~(-1)条件下,4～5 d完全降解400 mg·L~(-1)苯酚,且在藻接种浓度为0.2 g·L~(-1)条件下,小球藻具有最高的比生长速率;在藻菌接种浓度0.2 g·L~(-1)、藻菌比1∶1条件下,6 d内完全降解500 mg·L~(-1)的苯酚,且在各苯酚浓度(200～600 mg·L~(-1))下,小球藻叶绿素(a+b)含量较初始接种值增加了1.54～4.71倍。与简单芽胞杆菌共培养可以促进小球藻生长并提高其苯酚降解能力,在苯酚废水净化及资源化利用领域展现了一定的应用潜力。     

底物浓度影响微生物燃料电池性能和生物生长的模拟研究

建立了含有悬浮微生物、电极上生物量、可溶性化学底物和中介体的微生物燃料电池(MFC)数学模型。通过底物降解、生物增长和电流产生过程的模拟,考察了生物量和底物随时间的变化规律,底物质量浓度对生物量、底物降解和电流的影响。结果表明,当溶液中初始微生物量很少时,随着MFC反应的进行,生物主要富集在电极上,溶液中生物生长缓慢;MFC中的生物生长经历延滞期、对数期和平稳期,底物分解经历缓慢、快速和消耗殆尽3个阶段。底物质量浓度小于等于250 mg/L时,生物延滞期时间、底物缓慢分解阶段时间、生物生长到达平稳时间、底物消耗殆尽的时间和电流到达最大值所需的时间随着底物质量浓度的增加而缩短。底物质量浓度大于250 mg/L时,生物延滞期时间、底物缓慢分解阶段时间、生物生长到达平稳时间、底物消耗殆尽的时间和电流到达最大值所需的时间随着底物质量浓度的增加而增加。     

热解温度和时间对污泥生物碳理化性质的影响

污泥热解制备生物碳是一种环境友好的污泥处理处置途径。重点考察了热解温度及时间等因素对生物碳品质的影响。污泥取自厦门某城市污水处理厂脱水污泥（初始含水率为80%）,热解实验结果表明,随着热解温度的升高（从300～700℃）,热解时间的增加（2～4 h）,生物碳产率均下降;低温热解时（300℃）,生物碳偏酸性,而高温热解时（700℃）,生物碳偏碱性;生物碳N含量随着热解温度的升高、热解时间的增加而降低,而P、K及微量元素随着热解温度的升高,热解时间的增加而增加。DTPA浸提实验结果表明,高温热解能降低污泥生物碳中微量元素的有效性。     

重庆酸雨对陆地生态系统的影响和控制对策——中日酸雨合作研究总结

中日合作研究项目：酸沉降对陆地生态系统的影响及其控制对策的研究,于１９９０至１９９５年期间在中国重庆地区进行。本文是该项目最终研究结果主要方面的报导,包括大气污染和酸雨的状况,酸沉降对池塘、森林和土壤生态系统的影响以及大气污染和酸雨控制对策。该项研究为今后酸沉降生态监测的研究,打下了有力的基础。     

4种营养元素对水华鱼腥藻和四尾栅藻增殖的影响

以水华鱼腥藻和四尾栅藻分别作为蓝藻,绿藻代表藻种,采用均匀设计实验方法(uniform design experimentation,UDE)设计藻类AGP实验。采用通径分析法(Path Analysis,PA)对氮、磷、铁和锰在不同藻种增殖过程中的影响程度进行分析。结果表明,4种营养元素对水华鱼腥藻增殖影响的决策排序为Fe>TN>TP>Mn,微量金属元素铁是影响水华鱼腥藻(蓝藻)增殖的主要因素;对四尾栅藻增殖影响的决策排序为TN>TP>Fe>Mn,常量元素是影响四尾栅藻(绿藻)增殖的主要因素。联合通径分析法和逐步二次方回归分析法(QRA)建立的数学模型,可用于预判藻增殖。     

酸雨对污染环境中重金属化学行为的影响

综述了酸雨对污染环境中重金属化学行为的影响。在酸雨作用下 ,不同环境介质中重金属活性明显增强 ,化学形态转化明显 ,迁移能力和生态危害能力亦明显加强。探讨了控制酸雨发生、重金属污染环境修复技术以及开展复合污染环境化学风险评价的必要性     

酸雨对建筑材料的影响及防治研究综述

综合分析了酸雨对建筑外墙的涂料、石材、混凝土等主要建筑构件的腐蚀原理,并提出了防治措施,来预防酸雨对建筑材料的侵害。     

不同种植方式下伊乐藻生长对沉积物磷的影响

将伊乐藻以直接抛掷、直接扦插和断枝抛掷3种方式种植,测定其上覆水TP、DO、pH和沉积物中各形态磷。结果表明:(1)实验结束(120d)时,直接抛掷、直接扦插和断枝抛掷处理组的的生物量分别增加69.14、50.32、46.15g,从长期来看,直接抛掷最有利于伊乐藻生物量的增长。(2)实验结束时,直接抛掷、直接扦插和断枝抛掷处理组的沉积物中TP分别下降了8.90%、7.30%、5.40%;无机磷分别下降了11.80%、8.20%、6.60%;有机磷分别下降了7.47%、6.46%、2.65%;NaOH提取态磷分别下降了19.90%、17.20%、11.70%;HCl提取态磷分别下降了4.12%、3.47%、2.83%。直接抛掷种植伊乐藻对沉积物中各形态磷的去除效果最好。(3)上覆水TP与沉积物中各形态磷呈正相关,说明沉积物中的磷是上覆水中磷的重要来源;上覆水TP和沉积物各形态磷均与伊乐藻生物量呈负相关,说明伊乐藻可以有效去除上覆水和沉积物中的磷;DO和pH与生物量呈正相关,而与上覆水TP和沉积物各形态磷呈负相关,说明上覆水DO和pH主要受伊乐藻的影响。     

Effects of sulfur dioxide on growth, photosynthesis and enzyme activities of Chinese Guger-Tree seedlings

The Chinese Guger-Tree (Schima superba Gard et Champ var. superba) is an important harwood species in Taiwan where the ambient SO(2) concentration in some areas is high. Seedlings were raised in field chambers with and without SO(2) to determine whether this species is affected by this pollutant. After 4 weeks of exposure to 325 ppb of SO(2), the photosynthetic rate of seedlings decreased immediately. During the fumigation period, stem height growth was not inhibited, however, the stem diameter growth was reduced significantly. The dry weight of leaves was unchanged, while stem, root and total seedling weight were lower than those of control plants. Sulfhydryl groups in leaves increased by 75%, whereas they did not change in roots following SO(2) uptake. Superoxide dismutase in leaves did not change, however, peroxidase activity increased significantly. Results suggest that ambient SO(2) in some areas in Taiwan may affect the physiology and growth of the Chinese Guger-Tree.     

Combined effects of lanthanum ion and acid rain on growth, photosynthesis and chloroplast ultrastructure in soybean seedlings

Rare earth elements (REEs) have been accumulated in the agricultural environment. Acid rain is a serious environmental issue. In the present work, the effects of lanthanum ion (La³⁺) and acid rain on the growth, photosynthesis and chloroplast ultrastructure in soybean seedlings were investigated using the gas exchange measurements system, chlorophyll fluorometer, transmission electron microscopy and some biochemical techniques. It was found that although the growth and photosynthesis of soybean seedlings treated with the low concentration of La³⁺ was improved, the growth and photosynthesis of soybean seedlings were obviously inhibited in the combined treatment with the low concentration of La³⁺ and acid rain. At the same time, the chloroplast ultrastructure in the cell of soybean seedlings was destroyed. Under the combined treatment with the high concentration of La³⁺ and acid rain, the chloroplast ultrastructure in the cell of soybean seedlings was seriously destroyed, and the growth and of photosynthesis were greatly decreased compared with those of the control, the single treatment with the high concentration of La³⁺ and the single treatment with acid rain, respectively. The degree of decrease and destruction on chloroplast ultrastructure depended on the increases in the concentration of La³⁺ and acid rain (H⁺). In conclusion, the combined pollution of La³⁺ and acid rain obviously destroyed the chloroplast ultrastructure of cell and aggravated the harmful effect of the single La³⁺ and acid rain on soybean seedlings. As a new combined pollutant, the harmful effect of REEs ions and acid rain on plant should be paid attention to.     

Effects of Ginkgo biloba extract on growth,photosynthesis, and photosynthesis-related gene expression in Microcystis flos-aquae

Environmental Science and Pollution Research - The inhibitory effect of plants on algae offers a new and promising alternative method for controlling harmful algal blooms. Previous studies showed...     

Effects of copper, chromium and nickel on growth, photosynthesis and chlorophyll a synthesis of Chlorella pyrenoidosa 251

Individual and combined effects of three heavy metals; namely, copper, chromium and nickel, on growth, photosynthesis and chlorophyll a synthesis of the unicellular green alga, Chlorella pyrenoidosa 251, were determined. Within the concentration range of 0.1 to 1.0 mg litre(-1) of the three heavy metals tested on growth, photosynthesis and chlorophyll a synthesis of the alga, the order of toxicity of the three heavy metals was copper > chromium > nickel. The presence of one of the three heavy metals interacted synergistically with the other two heavy metals in various bimetallic combinations on growth, photosynthesis and chlorophyll a synthesis of the alga.     

不同水层光照强度对4种沉水植物生长的影响

选取金鱼藻(Ceratophyllum demersum)、轮叶黑藻(Hydrilla verticillata)、水盾草(Cabombacaroliniana)、苦草(Vallisneria gigantean)为试验材料,研究不同水层的光照强度对其存活率、株高、生物量等的影响,旨在找出这4种沉水植物在自然条件下的最...     

Effects of 2,4-D, glyphosate and paraquat on growth, photosynthesis and chlorophyll-a synthesis of Scenedesmus quadricauda Berb 614

The effects of 2,4-D, glyphosate and paraquat on growth, photosynthesis and chlorophyll-a synthesis by a freshwater green alga, Scenedesmus quadricauda Berb 614, were determined. These herbicides are the most often used in Hong Kong. Within the concentration range 0.02-200 mg/l, paraquat was more toxic than glyphosate and 2,4-D to the growth, photosynthesis and chlorophyll-a synthesis. The presence of 0.02, 0.2 or 2 mg/l of 2,4-D was not toxic to the alga. Algal growth, photosynthesis and chlorophyll-a synthesis were stimulated by the presence of low concentrations (0.02 or 0.2 and 0.02 mg/l, respectively) of 2,4-D and glyphosate. The presence of 0.02 or 0.2 mg/l of paraquat, 2 mg/l of glyphosate or 20 mg/l of 2,4-D was significantly inhibitory to the three test parameters, whereas the presence of 2 or more mg/l of paraquat, 20 or more mg/l of glyphosate or 200 mg/l of 2,4-D completely inhibited algal growth, photosynthesis and chlorophyll-a synthesis. The use of the alga as a bio-indicator of herbicide contamination in freshwater environment was discussed.     

Effects of aluminium in acid streams on growth and sporulation of aquatic hyphomycetes

We investigated, by field and laboratory experiments, the effects of aluminium in an acid stream (pH 5.0) on the growth and sporulation of aquatic hyphomycete fungi which degrade organic litter. The stream water had monomeric aluminium (Al(m)) concentrations of 9.1-13.4 microm - fifty times higher than a nearby circumneutral stream. Alder leaves submersed in the stream accumulated Al, most of which was tightly bound. Growth rates of four species of aquatic hyphomycetes were altered by inclusion of Al(m) in the culture medium. On a polypectate substrate, and on low-phosphate medium with glucose, growth rates increased significantly. On a low-nutrient substrate of homogenized alder leaves, growth rates were inhibited by aluminium. The pattern of mycelial growth was found to be different on a polypectate medium including Al(m), compared with a control without aluminium. There was a significant increase in hyphal radial growth and a decrease in the hyphal growth unit. The effect resembled the growth of a starved fungal colony. Treatment with Al(m) decreased pectinase production by the four fungal species tested. The capacity of these species to sporulate was reduced by flooding culture plates with Al(m) solution. These deleterious metabolic effects were most severe in isolates taken from circumneutral streams and less marked, though significant, in species originating from acid streams.     

Effects of ammonia from livestock farming on lichen photosynthesis

This study investigated if atmospheric ammonia (NH₃) pollution around a sheep farm influences the photosynthetic performance of the lichens Evernia prunastri and Pseudevernia furfuracea. Thalli of both species were transplanted for up to 30 days in a semi-arid region (Crete, Greece), at sites with concentrations of atmospheric ammonia of ca. 60 μg/m³ (at a sheep farm), ca. 15 μg/m³ (60 m from the sheep farm) and ca. 2 μg/m³ (a remote area 5 km away). Lichen photosynthesis was analysed by the chlorophyll a fluorescence emission to identify targets of ammonia pollution. The results indicated that the photosystem II of the two lichens exposed to NH₃ is susceptible to this pollutant in the gas-phase. The parameter PI_ABS, a global index of photosynthetic performance that combines in a single expression the three functional steps of the photosynthetic activity (light absorption, excitation energy trapping, and conversion of excitation energy to electron transport) was much more sensitive to NH₃ than the F_V/F_M ratio, one of the most commonly used stress indicators.     

Effects of ozone and simulated acid rain on birch seedling growth and formation of ectomycorrhizae

Four-week-old paper birch (Betula papyrifera Marsh.) seedlings, inoculated or non-inoculated with the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker & Couch and grown in steamed or non-steamed soil, were exposed to ozone (O(3)) and/or simulated acid rain (SAR). Plants were exposed to O(3) for 7 h per day on 5 days per week for 12 weeks. O(3) concentrations were maintained between 0.06 and 0.08 ppm. SAR was applied 10 min per day on 2 days per week. O(3), SAR, soil regime and mycorrhizal treatment did not significantly affect any of the measured variables. Interactions between O(3) and SAR, SAR and mycorrhizal treatment, soil regime and mycorrhizal treatment and ozone and soil regime had significant effects. Treatment of seedlings with pH 3.5 SAR caused increases in growth which were more apparent in birch exposed to O(3). Mucorrhizal treatment caused increased growth in non-steamed soil, while growth appeared to decrease in steamed soil. Birch seedlings grew much better in steamed soil. The implications of increased growth in steamed soil may demonstrate the importance of looking at the secondary effects of pollutants on soil-borne organisms.     

Effects of simulated acid rain on growth rate in a spruce-living spider

Growing juveniles of the spruce-living spider Pityohyphantes phrygianus were sprayed with water of different acidity--pH approximately 7 (control), 4.0 (acid rain) and 2.2-in a 2.5-month laboratory experiment. The growth rates did not differ between control and pH 4.0, while there was a significant growth reduction at pH 2.2. A low mortality occurred only in the pH 2.2 group. P. phrygianus seems to be resistant against acid rain although negative long-term effects cannot be ruled out.