An Experimental Burn to Restore a Moth-Killed Boreal Conifer Forest, Krasnoyarsk Region, Russia

Mechanical treatment and prescribed fire were used to restore a mixed conifer stand (Picea-Abies-Pinus) following mortality from an outbreak of Siberian moth (Dendrolimus superans sibiricus). Moth-killed stands often become dominated by Calamagrostis, a sod-forming grass. The large amount of woody debris and the sod hinder coniferous seedling establishment and development as well as creating conditions favorable to the establishment and propagation of wildfires. Fire has been demonstrated to be an effective method of reducing woody debris and eliminating sod, but the random nature and timing of wildfires often do not create conditions favorable for conifer regeneration. Our study was conducted in a mature fir dominated stand that died during an outbreak 6–8 years previously with most of the dead trees still standing. A bulldozer drove through the stand downing standing snags in late summer with 15–20 m between passes. Snags knocked down by the bulldozer and additional snag fall throughout the following winter increased downed dead wood 50–60% and large downed dead wood 80% compared to an adjacent untreated area. In June, a prescribed fire was set and fuel load consumption averaged 70%. Average soil temperatures during the burn ranged from 47 ^∘C at a depth of 2 cm to 10 ^∘C at 10 cm; hot enough to kill the grass. Following treatment, the potential for wildfire was reduced and the area was suitable for either natural conifer regeneration or planting without further mechanical site preparation.     

1株草螺属植物内生菌R-13的分离鉴定及对龙葵吸收土壤镉的影响

植物内生菌联合超积累植物修复重金属污染土壤可显著提高植物修复效率.从镉污染稻田水稻根系中分离获得1株编号为R-13的植物内生菌.分别利用显微观察、碳源利用及分子生物学手段将该菌株鉴定为1株红苍白草螺菌（Herbaspirillum rubrisubalbicans）;该菌株具有较强的耐Cd²⁺能力,在镉含量为300 mg·kg^-1的固体培养基上仍能生长.经显色反应发现R-13菌株具有产生铁载体和分泌吲哚乙酸（IAA）能力,此外,经Pikovskaya''s固体培养基和Ashby固体培养基试验表明R-13菌株溶磷作用微弱,但是具有较强的固氮能力.在盆栽试验中,利用高通量测序技术追踪R-13菌株在龙葵根部定殖情况,发现接种1次3 d后草螺菌属在龙葵根系内相对丰度相比空白对照（CK）增加201.88%,两次接种可使草螺菌属在龙葵根部的相对丰度相比CK增加1182.44%,接种5 d后草螺菌属在龙葵根系内相对丰度开始出现显著降低趋势.当接种20 mL·pot^-1菌液时对龙葵的根、茎、叶及果实中镉含量无显著影响,当接种菌液达到40 mL·pot^-1时可显著提高龙葵营养器官中的镉含量,当接种量达到200 mL·pot^-1时龙葵营养器官中镉含量最高.此时,根系中镉含量与对照组相比提高84.42%,茎秆中提高43.67%,叶片中提高64.06%,果实中提高20.29%.综上可见,根系接种植物内生草螺菌R-13可显著提高龙葵根系中草螺菌属的相对含量,同时可起到强化龙葵吸收镉的作用,该菌株在植物修复镉污染土壤技术中具有较好应用前景.     

北京市典型土著沉水植物对水体中硝酸盐和正磷酸盐的耐受性研究

以北京市3种典型土著沉水植物轮叶黑藻、狐尾藻和金鱼藻为研究对象,构建模拟水生生态系统,研究3种沉水植物对水体中NO₃^-和PO₄^3-的耐受性并确定其耐受范围.同时,对植物体内过氧化氢酶、丙二醛、叶绿素和蛋白质4种指标进行检测.结果表明,轮叶黑藻对NO₃^-具有较强的耐受性,耐受浓度可达8 mg·L^-1,金鱼藻和狐尾藻次之,耐受浓度为3~5 mg·L^-1;狐尾藻对PO₄^3-的耐受性最差,耐受浓度约为0.2 mg·L^-1,轮叶黑藻和金鱼藻的耐受性相当,当PO₄^3-浓度达到0.4 mg·L^-1时开始出现显著胁迫.因此,在本研究的实验条件下,当水体NO₃^-浓度<5 mg·L^-1、PO₄^3-浓度<0.2 mg·L^-1时,建议3种沉水植物同时种植;当NO₃^-浓度>5 mg·L^-1时,建议种植轮叶黑藻;当PO₄^3-浓度为0.2~0.4 mg·L^-1时,建议种植轮叶黑藻和金鱼藻.研究结果可为北京市再生水补给河湖水库的水生态修复及其沉水植物群落的构建提供一定的理论指导.     

松属植物地质历史及生物地理演变

松属（Pinus L.）约113种,是松科现代属中最原始的类群。松属植物种类丰富且研究领域广泛,对其已经积累的资料数据进行系统梳理总结十分必要。本文通过总结国内外松属大化石资料,结合分子系统发育、地质背景和地理隔离事件讨论了其地史分布及植物地理学意义;该属化石在早白垩世至全新世地层中均有记录。化石证据表明松属很可能在早白垩世（之前）起源于西欧地区,从这一起源地通过北大西洋陆桥扩散到北美洲东部,而东亚的类群可能是从北美洲西部经过白令陆桥散布的。在晚白垩世分化出双维管束松亚属Subgenus Pinus L.及单维管束松亚属Subgenus Strobus (D. Don) Lemmon,前者更接近祖先类群。古新世由于全球显著增温以及白垩纪末期大灭绝等地质事件的影响使松属数量急剧减少,在晚始新世至中新世时期随着气温转凉转冷再次分化扩散,中新世达到其发展高峰且分布面貌与现代类群近似。松属多样性时空历史可能和新生代气候变迁及晚新生代构造运动塑造的山地隆升等环境变化紧密相关。     

南京地区污水厂、自来水厂及长江中抗性基因MCR-1和NDM-1的污染特征

近年来,新型抗性基因以其易传播和耐药广等特性,展现出比传统抗性基因更严峻的健康风险,在临床卫生领域受到广泛关注,但目前对其在环境中的行为和风险研究很少.为此,考察了2种有代表性的新型抗性基因MCR-1和NDM-1的污染特征,并借助荧光定量PCR探索了长江下游（南京段）及附近污水厂和自来水厂中MCR-1和NDM-1的分布特征,进而采用RDA（冗余性分析）评价了分布特征受水质指标的影响效果.结果表明:①污水厂进水中MCR-1和NDM-1绝对丰度较高,且随处理流程呈下降趋势,总去除率分别为92.5%和92.7%,但出水中MCR-1和NDM-1绝对丰度仍分别达2.5×108和7.0×106 copies/L.②长江下游（南京段）各采样点MCR-1和NDM-1绝对丰度的范围分别为8.5×107~3.5×109和4.3×105~2.1×107 copies/L,随水流方向呈降低趋势,但在个别采样点出现异常升高的情况,主要受该区域人为污染的影响.③自来水厂处理工艺对MCR-1和NDM-1去除率分别为75.0%和70.6%,但出水中存留的MCR-1和NDM-1绝对丰度分别达1.4×107和6.3×104 copies/L,且MCR-1和NDM-1在排泥水中大量富集.④MCR-1绝对丰度与ρ（COD_Cr）、ρ（NH₃-N）、电导率呈正相关,而NDM-1绝对丰度仅和浊度存在弱相关关系,与其他水质指标无明显相关性.研究显示,污水处理工艺无法有效去除MCR-1和NDM-1,大量抗性基因通过污水厂出水排入长江,同时自来水厂以含有较高绝对丰度抗性基因的长江水作为水源水,最终自来水厂出水中残存的抗性基因可能进入人体,生态健康风险较大.      

Adsorptive behaviors of humic acid onto freshly prepared hydrous manganese dioxides

This study focused on the adsorptive behaviors of humic acid onto freshly prepared hydrous MnO₂(s) (δMnO₂), and investigated the feasibility of employing δMnO₂ for humic acid removal from drinking water. Effects of such parameters as molecular mass of humic acid, kinds of divalent cations on adsorptive behaviors and possible mechanisms involved were investigated. This study indicated that humic acid with higher molecular mass exhibited more tendency of adsorbing onto δMnO₂ than that with lower molecular mass. Ca²⁺ facilitated more humic acid adsorption than Mg²⁺; UV-Vis spectra analysis indicated higher capabilities of Ca²⁺ coordinating with acidic functional groups of humic acid than that of Mg²⁺. Additionally, ζ potential characterization indicated that Ca²⁺ showed higher potential of increasing gz potential of δMnO₂ than Mg²⁺. Ca²⁺ of 1.0 mmol/L increased ζ potential of δMnO₂ from −37 mV (pH 7.9) to +7 mV (pH 7.2), while 1.0 mmol/L Mg²⁺ increased to lower value as −9 mV (pH 6.5), correspondingly. Fourier transform infrared (FTIR) spectra demonstrated the adsorption of humic acid onto δMnO₂, showing the important roles of-COO⁻ functional groups and surface Mn-OH in the adsorption of humic acid onto δMnO₂. Translated from Acta Scientiae Circumstantiae, 2005, 25(3): 351–355 [译自: 环境科学学报]     

超富集植物藿香蓟(Ageratum conyzoides L.)对镉污染农田的修复潜力

为探究超富集植物藿香蓟(Ageratum conyzoides L.)对镉(Cd)污染农田土壤的修复潜力,通过野外调查,原土盆栽试验和田间试验,测定藿香蓟及其根系土壤Cd含量,计算藿香蓟的富集系数和去除率.结果表明,野外调查中不同铅锌矿区生长的藿香蓟叶片中Cd含量最大值为77. 01 mg·kg~(-1),盆栽试验中,高含量Cd土壤处理(T2)中,地上部Cd积累量达到69. 71mg·kg~(-1),其地上部Cd富集系数为6. 09,在低含量Cd土壤处理(T1)中,藿香蓟对Cd的富集特性与其在高含量条件下对Cd的富集特性一致.藿香蓟对Cd表现出稳定的积累特性.田间试验中,污染区藿香蓟中地上部Cd含量均值为21. 13 mg·kg~(-1),富集系数为6. 93,使用藿香蓟修复Cd污染土壤每亩地种植三茬藿香蓟的去除率为13. 2%～15. 6%.使用超富集植物藿香蓟修复农田Cd污染具有较好的工程应用前景.     

无柄小叶榕对盐碱地Cd、Cu的吸收特性及修复潜力

采用盆栽试验,研究无柄小叶榕(Ficus concinna var.Subsessilis)对盐碱地土壤重金属Cd和Cu的富集和转运能力,并探讨投加生物表面活性剂鼠李糖脂(RL)对无柄小叶榕生长及其吸收Cd、Cu的影响.结果表明,人工模拟盐碱环境下无柄小叶榕能在不同浓度Cd、Cu单独或复合投加胁迫下正常生长,且体内重金属含量随投加浓度增大而升高,均表现为根地上部分;无柄小叶榕对Cd和Cu具有较强的富集能力,Cd的最大生物富集系数(BCF)为4.52±0.73,Cu为2.1±0.18,BCF值随着重金属投加浓度的增大逐渐减小,Cd、Cu转移系数(TF)均小于1;在Cd 50 mg·kg~(-1)、Cu 400 mg·kg~(-1)下的修复率最高分别为4.07%和2.66%;投加鼠李糖脂可以显著提高无柄小叶榕体内重金属的含量,土壤Cd 25 mg·kg~(-1)时,根部Cd含量最大提高了2.38倍,Cu 50 mg·kg~(-1)时根部Cu含量最大提高了1.91倍.综上,无柄小叶榕对温州重金属污染的盐碱地有很好的修复潜力,投加生物表面活性剂可有效提高无柄小叶榕对重金属Cd和Cu的吸收富集效率.     

两种不同镉富集能力油菜品种耐性机制

利用水培试验研究了不同浓度镉(cadmium,Cd)胁迫条件下(0、2和5 mg·L~(-1))两种Cd富集能力油菜品种[秦油1号(QY-1)和三月黄(SYH)]生长状况与Cd富集特征的差异,并从Cd亚细胞区隔化和抗氧化酶活性等角度探索了两种油菜Cd富集能力的差异机制,并通过田间试验进行验证.结果表明,水培条件下,这两种油菜在Cd胁迫下生长均未受到明显的抑制.在低浓度Cd(2 mg·L~(-1))处理下,两种油菜地上部Cd含量无显著差异,在高浓度Cd(5 mg·L~(-1))胁迫下SYH的地上部和根部Cd含量均显著高于QY-1,分别提高32. 05%和99. 57%,同时其根部生物富集系数(BCF)也较QY-1显著提高.对两种油菜叶片中Cd亚细胞区隔化研究结果表明,随着Cd处理浓度的增加,QY-1和SYH叶片中Cd在热稳定蛋白和镉富集颗粒组分的分布分别提高了143. 69%、118. 91%和63. 34%、118. 91%,由此可见将Cd区隔在热稳定蛋白和镉富集颗粒体等重金属解毒组分是油菜在亚细胞水平上的重要解毒机制.同时,高浓度Cd胁迫下SYH叶中Cd在细胞碎屑组分的含量达QY-1的4. 41倍,可知Cd在细胞碎屑组分中的分布是导致两种油菜Cd富集能力差异的重要机制.结合对两种油菜抗氧化酶活性研究结果,发现抗氧化酶系统可能是QY-1应对高浓度Cd胁迫的重要解毒机制,而SYH则更多地通过将Cd区隔在金属低活性的亚细胞组分来减轻其毒性.田间试验结果验证表明,SYH地上部和地下部Cd含量均显著高于QY-1,分别是QY-1的2. 34和1. 43倍.综上所述,SYH具有更高的Cd提取量和富集能力,具有应用于中轻度Cd污染农田修复的潜力.     

Improvement of detection method of Cryptosporidium and Giardia in reclaimed water

Cryptosporidium and Giardia are two typical species of pathogenic protozoans that seriously endanger water quality. Previous works indicated that detection of Cryptosporidium and Giardia with modified United States Environmental Protection Agency (USEPA) method-1623 using a membrane filtration-elution for sample concentration attained better recovery and lower cost compared to the USEPA method-1623. Several improvements of membrane filtration-elution step as well as immunomagnetic separation (IMS) steps were investigated and an optimized method for detection of Cryptosporidium and Giardia in wastewater reclamation system was recommended in this paper. The experimental results show that an overnight soak of the membrane after scraping and vortex agitation before elution could enhance and stabilize the recovery. Increasing turbidity to 4 NTU by adding kaolin clay before filtration could effectively improve the recovery of low-turbidity water. Washing the concentrate after centrifugation and twice acid dissociation both reduced the impact of water quality to protozoan recovery. Protozoans in different water samples were determined by this optimized method, and the recovery of Cryptosporidium and Giardia were above 70% and 80% respectively, much higher than the acceptance of method-1623. __________ Translated from Environmental Science, 2006, 27(12): 2547–2552 [译自: 环境科学]     

绿狐尾藻对铜绿微囊藻和羊角月牙藻的抑藻效应

分别将不同起始浓度(10~5、10~6、10~7、10~8和10~9ind.·L~(-1))的铜绿微囊藻和羊角月牙藻分组与绿狐尾藻进行共培养,连续10 d,每天测定各组铜绿微囊藻或羊角月牙藻的光密度值,用以确定绿狐尾藻对两种藻类不同浓度的生长抑制情况.结果表明,2. 5 g·(200 m L)~(-1)的绿狐尾藻对起始浓度为10~7ind.·L~(-1)和10~8ind.·L~(-1)的铜绿微囊藻具有明显的抑制作用;而对实验所设的所有起始浓度的羊角月牙藻生长均没有显著的抑制作用.并且,采用溶剂浸提与气相色谱-质谱联用(GC-MS)测定的方法,分析了绿狐尾藻粉末浸提液和绿狐尾藻生长液中可能存在的化感物质,通过分析,确定棕榈酸是绿狐尾藻分泌的化感物质之一,并且发现了3种可能是绿狐尾藻分泌的新型化感物质:3-乙基-3-甲基庚烷、磷酸三乙酯和酞酸二丁酯.     

光倒刺鲃、白鲢协同投放抑制丝状藻(水绵)藻华围隔研究

为探究高效与安全抑制丝状藻藻华的方法,利用光倒刺鲃(Spinibarbus hollandi)、白鲢(Hypophthalmichthys molitrix)的食性特点,研究了不同密度(低密度(L)40 g·m-3、高密度(H)80 g·m-3)与不同投放比例(光倒刺鲃∶白鲢=3∶1、1∶1、1∶3)协同作用下,对围隔内水体丝状藻水绵(Spirogyra sp.)的抑制效果,以及对水生植物和水质的影响.结果表明,光倒刺鲃可以显著摄食丝状藻水绵,且在低密度、高比例(3∶1)时,即对丝状藻的生长具有明显抑制作用.高密度(80 g·m-3)投放光倒刺鲃、白鲢,无论比例如何,都会引起水体水质下降,引起轻微富营养化,并导致浮游藻类生物量上升,不适用于本试验水体.在本试验条件下,高密度(80 g·m-3)投放条件下,白鲢可以抑制浮游生物总量,H(1∶3)、H(1∶1)组中,呈现藻类小型化的趋势;而在低密度(40 g·m-3)投放条件下,未发现浮游藻类有小型化趋势.本试验L(3∶1)组,即光倒刺鲃30 g·m-3、白鲢10 g·m-3,可以有效控制试验水体丝状藻水绵滋生,且能够兼顾改善水质.     

Scale-dependent analysis of an otter–crustacean system in Argentinean Patagonia

The Southern river otter or ‘huillin’, Lontra provocax, is an endangered species endemic of the Andean Patagonian region of Argentina and Chile. It feeds almost exclusively on the genera of macro-crustacea: Aegla and Sammastacus. The aim of this study was to analyse the role of food availability on the huillin’s distribution using a scale-dependent analysis of crustacean and otter distributions. We compared the distributions of otters and macro-crustaceans along a north–south regional gradient, between river basins of northern Patagonia, in an altitudinal gradient within a river basin, and between habitat types within a lake. We investigated the distribution of otters by sign surveys along lake shores, river banks and marine coasts, and of crustaceans using surveys in the water, undigested remains in mink (Mustela vison) scats, presence of external skeletons at the waterside and through interviews with local people. Our results show that there were heterogeneities in the distributions of macro-crustaceans at four scales and these were generally reflected in the distributions of freshwater otters. We conclude that the main factor limiting the distributions of L. provocax in freshwater environments is the availability of macro-crustaceans. This paper shows how scale-dependent type analyses of population distribution serves as a method for identifying key environmental factors for species for which the use of long-term demographies is unfeasible.     

Degradation of 4-aminophenol by hydrogen peroxide oxidation using enzyme from Serratia marcescens as catalyst

This paper reports on the degradation of 4-aminophenol using hydrogen peroxide as oxidizer and the enzyme from Serratia marcescens AB 90027 as catalyst. The effecting factors during degradation and the degrading mechanism were studied. Also, the location of the enzyme in the cell, which could catalyze the degradation of 4-aminophenol, was analyzed. The results showed that to degrade 50 mL of 4-aminophenol whose concentration was 500 mg/L, the optimal conditions were: volume of H₂O₂ = 3 mL, temperature = 40–60°C and pH = 9–10. In the degradation process, 4-aminophenol was first converted to benzoquinone and NH₃, then organic acids including maleic acid, fumaleic acid, and oxalic acid were formed, and then finally CO₂ and H₂O were generated as final products. The enzyme that could catalyze the degradation of 4-aminophenol was mainly extracellular enzyme. Translated from Environmental Chemistry, 2006, 25(2): 141–144 [译自: 环境化学]     

Contribution of anadromous fish to the diet of European catfish in a large river system

Many anadromous fish species, when migrating from the sea to spawn in fresh waters, can potentially be a valuable prey for larger predatory fish, thereby efficiently linking these two ecosystems. Here, we assess the contribution of anadromous fish to the diet of European catfish (Silurus glanis) in a large river system (Garonne, southwestern France) using stable isotope analysis and allis shad (Alosa alosa) as an example of anadromous fish. Allis shad caught in the Garonne had a very distinct marine δ¹³C value, over 8‰ higher after lipid extraction compared to the mean δ¹³C value of all other potential freshwater prey fish. The δ¹³C values of European catfish varied considerably between these two extremes and some individuals were clearly specializing on freshwater prey, whereas others specialized on anadromous fish. The mean contribution of anadromous fish to the entire European catfish population was estimated to be between 53% and 65%, depending on the fractionation factor used for δ¹³C.     

Bio-char Sequestration in Terrestrial Ecosystems – A Review

The application of bio-char (charcoal or biomass-derived black carbon (C)) to soil is proposed as a novel approach to establish a significant, long-term, sink for atmospheric carbon dioxide in terrestrial ecosystems. Apart from positive effects in both reducing emissions and increasing the sequestration of greenhouse gases, the production of bio-char and its application to soil will deliver immediate benefits through improved soil fertility and increased crop production. Conversion of biomass C to bio-char C leads to sequestration of about 50% of the initial C compared to the low amounts retained after burning (3%) and biological decomposition (< 10–20% after 5–10 years), therefore yielding more stable soil C than burning or direct land application of biomass. This efficiency of C conversion of biomass to bio-char is highly dependent on the type of feedstock, but is not significantly affected by the pyrolysis temperature (within 350–500 ^∘C common for pyrolysis). Existing slash-and-burn systems cause significant degradation of soil and release of greenhouse gases and opportunies may exist to enhance this system by conversion to slash-and-char systems. Our global analysis revealed that up to 12% of the total anthropogenic C emissions by land use change (0.21 Pg C) can be off-set annually in soil, if slash-and-burn is replaced by slash-and-char. Agricultural and forestry wastes such as forest residues, mill residues, field crop residues, or urban wastes add a conservatively estimated 0.16 Pg C yr⁻¹. Biofuel production using modern biomass can produce a bio-char by-product through pyrolysis which results in 30.6 kg C sequestration for each GJ of energy produced. Using published projections of the use of renewable fuels in the year 2100, bio-char sequestration could amount to 5.5–9.5 Pg C yr⁻¹ if this demand for energy was met through pyrolysis, which would exceed current emissions from fossil fuels (5.4 Pg C yr⁻¹). Bio-char soil management systems can deliver tradable C emissions reduction, and C sequestered is easily accountable, and verifiable.     

Host pollination mode and mutualist pollinator presence: net effect of internally ovipositing parasite in the fig–wasp mutualism

The Ficus–their specific pollinating fig wasps (Chalcidoidea, Agaonidae) interaction presents a striking example of mutualism. Figs also shelter numerous non-pollinating fig wasps (NPFW) that exploit the fig–pollinator mutualism. Only a few NPFW species can enter figs to oviposit, they do not belong to the pollinating lineage Agaonidae. The internally ovipositing non-agaonid fig wasps can efficiently pollinate the Ficus species that were passively pollinated. However, there is no study to focus on the net effect of these internally ovipositing non-agaonid wasps in actively pollinated Ficus species. By collecting the data of fig wasp community and conducting controlled experiments, our results showed that internally ovipositing Diaziella bizarrea cannot effectively pollinate Ficus glaberrima, an actively pollinated monoecious fig tree. Furthermore, D. bizarrea failed to reproduce if they were introduced into figs without Eupristina sp., the regular pollinator, as all the figs aborted. Furthermore, although D. bizarrea had no effect on seed production in shared figs, it significantly reduced the number of Eupristina sp. progeny emerging from them. Thus, our experimental evidence shows that reproduction in Diaziella depends on the presence of agaonid pollinators, and whether internally ovipositing parasites can act as pollinators depends on the host fig’s pollination mode (active or passive). Overall, this study and others suggest a relatively limited mutualistic role for internally ovipositing fig wasps from non-pollinator (non-Agaonidae) lineages.     

Detection of Escherichia coli in wastewater based on enzyme immunoassay

This research describes a fast detection method on the basis of enzyme-linked immunosorbent assay (ELISA) for Escherichia coli in drainage of wastewater treatment plants. Optimized conditions such as the reaction format (sandwich or direct), the concentrations of diluted horseradish peroxidase (HRP)-E. coli conjugate, and anti-HPR antibody and pretreatment of E. coli were studied. Those results showed that the linear range of detection for E. coli was 10 cfu/mL-6 × 10⁴ cfu/mL. Compared with conventional methods, it is a convenient and sensitive detection method with low cost. Translated from Environmental Science, 2005, 26(5): 128–131 [译自: 环境科学]     

氧化石墨烯对邻苯二甲酸二丁酯藻毒性的影响

以海洋微藻青岛大扁藻(Platymonas helgolanidica var.tingtaoensis)为受试对象,研究了氧化石墨烯(graphene oxide,GO)与邻苯二甲酸二丁酯(dibutyl phthalate,DBP)单独及共同对青岛大扁藻的急性毒性效应,考察了藻细胞的生长状况,光合色素产量,细胞通透性,氧化应激指标及扫描电镜,以探讨GO的加入对DBP藻毒性的影响.结果表明,低浓度GO(0.1~10 mg·L~(-1))对青岛大扁藻的藻密度和叶绿素产量无明显影响,但藻细胞通透性随GO浓度升高显著增加(P0.05),10mg·L~(-1)时达到空白组的2.2倍.DBP对青岛大扁藻的EC50,96 h为(11.14±0.80)mg·L~(-1),其毒性远大于GO(EC50,96 h大于100mg·L~(-1)).1 mg·L~(-1)GO的加入使DBP的EC50,96 h降低到(4.93±2.14)mg·L~(-1),低浓度GO对DBP藻毒性表现出一定的增强作用.1 mg·L~(-1)的GO加入时,对低浓度DBP组(0.1~2 mg·L~(-1))的藻密度、叶绿素产量、细胞通透性水平没有显著性影响,但加剧了高浓度DBP组(4 mg·L~(-1))对藻密度、叶绿素产量的抑制,使单个藻细胞内ROS和SOD平均增加了21%和7%.扫描电镜结果发现GO对藻细胞具有覆盖,包裹及聚集作用,这些可能是DBP藻毒性增强的主要原因.该结果为揭示新型污染物碳纳米材料对海洋生物的风险提供了数据支持.