Evaluation of endocrine disruption and dioxin-like effects of organic extracts from sewage sludge in autumn in Beijing,China

Study on effective disposal and utilization of sewage sludge has recently been the target of growing interest in China. However, potential risks are associated with the use of sludge due to its contamination with toxic organics, heavy metals and pathogenic microorganisms. In this study, a screening assessment was conducted on sewage sludge samples collected from 17 different sewage treatment plants in Beijing, based on a batch of in vitro bioassays, including a set of recombinant gene yeast assays for endocrine disruption, and an ethoxy resorufin-O- deethylase （EROD） assay using H4IIE cells for aryl hydrocarbon receptor （Ah-R） agonistic activities. Our results suggested that moderate levels of estrogen receptor agonistic activities （0.9 ng E2. g-1 to 6.8 ng E2. gl, dw）, but relative higher androgen receptor antagonistic activ- ities （nd to 45%）, progestin receptor antagonistic activities （nd to 80%） and Ah-R agonistic activities （1390 to 6740 pg 2,3,7,8-tetrachlorodibenzo-p-dioxin （TCDD）·g-1, dw） were found in sewage sludge samples. However, there were no significant correlations between the toxic effects of sewage sludge and the sewage treatment processes. In addition, the 17β-estradiol （E2） equivalent quantity （EEQ） level of the sewage sludge was increased after the composting treatment, whereas the 2,3,7,8-tetrachlorodi- benzo-p-dioxin toxic equivalent quantity （TEQ） level of sewagesludge composted was much lower than that of sewage sludge.     

干旱胁迫和复水对梨幼树生理特性的影响

为了解植物干旱生理适应机制和恢复机制,以梨品种‘翠冠’和‘黄冠’幼树为试材,研究土壤干旱胁迫及复水条件下叶片光合参数、叶片相对含水量、叶片质膜透性、超氧化物歧化酶活性及脯氨酸含量的变化特性.结果显示:1)随着干旱胁迫的加剧,两品种的叶片净光合速率、气孔导度和蒸腾速率均呈下降趋势;‘翠冠’叶片胞间CO2浓度呈先降后升的趋势,而‘黄冠’呈持续下降趋势,但‘黄冠’光合作用的4项指标明显高于‘翠冠’;复水后,两品种的光合指标恢复显著,但均未超过对照水平.2)干旱胁迫引起两品种的叶片相对含水量急剧下降,叶片质膜透性和脯氨酸含量显著升高,超氧化物歧化酶活性呈先升后降趋势;复水后,两品种的4项指标不同程度地得以恢复,但大部分指标没有恢复到对照水平,其中‘黄冠’各项指标在复水前后的变化幅度比‘翠冠’更小.综合分析表明,‘翠冠’和‘黄冠’对干旱胁迫的响应存在差异,‘黄冠’对干旱逆境具有更强的适应能力.     

Bioaccumulation and adverse effects of trace metals and polycyclic aromatic hydrocarbons in the common onion Allium cepa as a model in ecotoxicological bioassays

The common onion Allium cepa can be easily used in ecotoxicological bioassays to evaluate the bioavailability and adverse effects of pollutants and complex mixtures like waste, industrial effluent or coal-mining drainage that contain elevated levels of trace metals and polycyclic aromatic hydrocarbons (PAHs). In this study, onions were exposed for 7 days to individual metals (1?µg?mL^?1), i.e., aluminium, copper, iron and manganese, or PAHs (1.5?ng?mL^?1), i.e., benzo[a]antracene and benzo[a]pirene. Biological effects, measured as growth inhibition of roots and leaves, were integrated with analysis of bioaccumulation in roots, bulbs and leaves. Copper, iron and benzo[a]pirene caused a significant inhibition in root development of newly formed tissues, whereas only slight variations were caused by other chemicals; the number of new root filaments and the length of the leaves did not show significant variations, thus not representing sensitive parameters to evaluate adverse effects of pollutants in A. cepa. Chemicals bioaccumulation was always significant in roots, whereas levels in bulbs and leaves exhibited increased levels only for manganese, and a decrease for aluminium. The overall results confirmed the sensitivity of the bioassays with A. cepa, suggesting their utility for future applications to evaluate the adverse effects of complex mixtures containing metals or PAHs.     

水源水中有机提取物生殖毒性评价和敏感检测指标的筛选（Reproductive Toxicity of Drinking Source Water and Selection of Sensitive Bioassays）

以原代培养的大鼠睾丸细胞为体外毒性试验靶细胞,采用支持细胞、生精细胞、间质细胞的形态、细胞活力、胞外乳酸脱氢酶(LDH)活力、细胞早期凋亡坏死率和间质细胞睾酮分泌量5种检测指标评价了X市和L市水源水中有机提取物的生殖毒性,并筛选了对痕量有机污染物敏感的生殖毒性指标.研究结果表明,两市水源水中有机提取物皆可引起支持细胞、间质细胞和生精细胞形态的变化,相比较而言,对生精细胞的影响更严重.X市水源水有机提取物对3种生殖细胞胞外LDH活力没有显著影响(p>0.05);而在L市水源水中有机提取物的暴露下,支持细胞和间质细胞胞外LDH活力显著增强(p<0.01).X市水源水中有机提取物可使间质细胞睾酮分泌量显著减少(p<0.01);而L市水源水有机提取物对间质细胞睾酮分泌量无明显影响(p>0.05).两市水源水有机提取物均能不同程度地诱发大鼠睾丸细胞损伤,生精细胞对环境毒物是比较敏感的细胞,细胞形态、活力、LDH活力、凋亡坏死率、睾酮分泌量等生殖毒理学检测指标可用于饮用水源地水质的评价.     

部分菊科入侵种种子(瘦果)的萌发能力和幼苗建群特性

对入侵种种子生物学各方面的了解有助于更好地预测入侵趋势和评估可持续管理的策略.研究通过对部分菊科入侵种种子(瘦果)进行的室内萌发实验和土壤埋藏实验,通过与相关研究的对比和分析,对这些入侵种的萌发能力和幼苗建群特性进行了研究.10个入侵种种子室内萌发实验的结果表明,在25℃、12h光照的情况下,除钻形紫菀和一年蓬以外,被研究的其它8个种的终萌发率超过了50%,而且都显示出早期快速萌发的特点.用SPSS的曲线拟合工具对10个种的累积萌发趋势进行了曲线回归分析,对应的最佳模型均为三次曲线方程.不同土壤埋藏深度下幼苗出苗实验的结果表明,菊科8个入侵种的种子在表土的出苗率均最高,随着覆土厚度的增加,种子的出苗率逐渐降低,当覆土厚度超过3 cm以上时,所有种子均不能出苗.种子在不同的埋藏深度的出苗情况与种子的大小有关,较大种子破土能力相对较强;种子在不同的埋藏深度的出苗情况与种子本身的萌发能力也相关.土壤埋藏期限的实验结果表明,随埋藏时期的增加,小蓬草、苏门白酒草和一年蓬3个人侵种种子的活力逐步降低,在土壤中埋藏12个月后,其活力分别为21.34%、18.15%和27.38%.这些入侵种较广的种子萌发温度适应范围和高萌发率为防除工作带来了困难.在生产上,可通过不同时期的翻耕、将种子深埋等措施减少这些入侵种的危害.     

甜椒穴盘苗对不同程度水分胁迫-复水的生理生化响应

对温室甜椒穴盘苗进行水分处理,探讨了不同程度水分胁迫-复水过程中叶片生理生化特性的变化.叶片相对含水量(RWC)、渗透势随基质水分减少而降低,渗调能力逐步增强.POD、SOD、CAT酶活性随水分减少而上升,SOD对水分胁迫最敏感,复水后主要由POD、CAT负责清除H2O2和过氧化物.游离氨基酸、脯氨酸随基质水分减少急剧上升,复水后大幅下降,可能为水分胁迫下主要渗透调节物质.水分胁迫下,甜椒叶片可溶性蛋白主要降解为氨基酸的形式参与渗透调节.RWC降至45%(停水后d3)时,可溶性糖显著积累,但明显晚于氨基酸,但它基础含量高,主要在较为严重的水分胁迫时发挥作用.尽管水分胁迫使保护酶活性和渗透调节能力均提高,但任何程度的胁迫均不可避免伤害幼苗.穴盘苗生产中,建议“水分胁迫锻炼”时间以不超过3d逐步达到RWC≥45%为宜.图4表2参12     

Necessity of Toxicity Assessment in Turkish Industrial Discharges (Examples from Metal and Textile Industry Effluents)

Toxicity of some organic and inorganic chemicals to microorganisms is an important consideration in assessingtheir environmental impact against their economic benefits.Microorganisms play an important role in several environmentalprocesses, both natural and engineered. Some organic and inorganics at toxic levels have been detected in industrial discharges resulting in plant upsets and discharge permit violations. In addition to this, even though in some cases the effluent wastewater does not exceed the discharge limits,the results of toxicity tests show potential toxicity. Toxicityknowledge of effluents can benefit treatment plant operators inoptimising plant operation, setting pre-treatment standards, and protecting receiving water quality and in establishing sewer discharge permits to safeguard the plant. In the Turkish regulations only toxicity dilution factor (TDF) with fish is part of the toxicity monitoring program of permissible wastewater discharge. In various countries, laboratory studiesinvolving the use of different organisms and protocol for toxicity assessment was conducted involving a number of discharges.In this study, it was aimed to investigate the acute toxicity of textile and metal industry wastewaters by traditional and enrichment toxicity tests and emphasize the importance of toxicity tests in wastewater discharge regulations. The enrichment toxicity tests are novel applications and give anidea whether there is potential toxicity or growth limiting and stimulation conditions. Different organisms were used suchas bacteria (Floc and Coliform bacteria) algae (Chlorella sp.), fish (Lepistes sp.) and protozoan (Vorticella sp.) to represent four tropic levels. The textile industry results showed acute toxicity for at least one organism in 8 out of 23 effluent samples. Acute toxicity for at least two organisms in 7 out of 23 effluent sampling was observed for the metal industry. The toxicity test results were assessed with chemical analyses such as COD, BOD, color and heavy metals. It was observed that the toxicity of the effluents could not be explained by using physicochemical analyses in 5 cases for metal and 4 cases for the textile industries. The results clearly showed that the useof bioassay tests produce additional information about the toxicity potential of industrial discharges and effluents.     

Influences of Climatic Change on Some Ecological Processes of an Insect Outbreak System in Canada's Boreal Forests and the Implications for Biodiversity

Insect outbreaks are a major disturbance factor in Canadian forests. If global warming occurs, the disturbance patterns caused by insects may change substantially, especially for those insects whose distributions depend largely on climate. In addition, the likelihood of wildfire often increases after insect attack, so the unpredictability of future insect disturbance patterns adds to the general uncertainty of fire regimes. The rates of processes fundamental to energy, nutrient, and biogeochemical cycling are also affected by insect disturbance, and through these effects, potential changes in disturbance patterns indirectly influence biodiversity. A process-level perspective is advanced to describe how the major insect outbreak system in Canadian forests, that of the spruce budworm (Choristoneura fumiferana Clem. [Lepidoptera: Tortricidae]), might react to global warming. The resulting scenarios highlight the possible importance of natural selection, extreme weather, phenological relationships, complex feedbacks, historical conditions, and threshold behavior. That global warming already seems to be affecting the lifecycles of some insects points to the timeliness of this discussion. Some implications of this process-level perspective for managing the effects of global warming on biodiversity are discussed. The value of process-level understanding and high-resolution, long-term monitoring in attacking such problems is emphasized. It is argued that a species-level, preservationist approach may have unwanted side-effects, be cost-ineffective, and ecologically unsustainable.     

桤木育苗技术试验

随着退耕还林等林业重点工程在我省大规模实施,桤木已在全省广泛引种栽培并成为我省主要造林树种之一,本文作者根据桤木的生物学、生态学特性,通过多年的实践,从种子采收及贮藏,圃地选择及作床,浸种及播种,覆盖及揭草,田间管理及防病虫等方面出发,总结、归纳了一套简单、实用、易于掌握的育苗技术,具有较高的科学性和实用性.     

用幼苗法指示污泥和土壤中重金属的植物有效性

利用小麦幼苗与黑麦幼苗研究了污泥和土壤中重金属的植物有效性,并对二者进行了比较。结果表明, 在两种污灌区土壤、四种污泥以及一种污泥施用于两种清洁土壤中,黑麦和小麦测定的Cd,Pb,Cu,Zn,Ni五种重金属有效性的顺序,以及有效性大小的数量级上是一致的;除了在污泥中,二者的茎Pb,Ni及根Zn相关不显著,以及在Lou土中施用污泥后,两种植物各部位相关不好外,在污泥及污泥施于赤红壤各处理中黑麦与小麦相关均匀为极显著。上述结果表明,应用小麦幼苗可以替代黑麦幼苗指标土壤中重金属的植物有效性,但同时也应考虑不同植物间的差异。