Genetic variability in Gymnodiniaceae ITS regions: implications for species identification and phylogenetic analysis

The internal transcribed spacer (ITS) regions and 5.8S rRNA genes from several strains of toxic Gymnodiniaceae were sequenced and subjected to phylogenetic analysis with other Gymnodiniaceae species. Sequence comparisons showed that high sequence divergence existed in Gymnodiniaceae, especially in the genus Gymnodinium. The amplicons of the ITS regions from Amphidinium and Gyrodinium species were 438–439 and 604–605 bp, respectively, and those of the Gymnodinium species ranged from 575 to 615 bp. The mean distance value within Gymnodinium, calculated from the ITS sequence, was 0.68827 (range: 0–0.92323), 0.11342 for Amphidinium (range: 0.00467–0.17120) and 0.2005 for Karenia (range: 0.00521–0.29971). Low distance values were found within the species Gyrodinium instriatum (<0.01) and Karlodinium micrum (<0.02). Amphidinium remarkably had a shorter ITS than did other genera in Gymnodiniaceae, this implied that Amphidinium might be distant from the other Gymnodiniaceae and supported Saunders opinion that the taxonomy of Amphidinium needs to be reevaluated. Largely congruent phylogenetic trees were produced by the maximum-parsimony method (PAUP), maximum-likelihood method (PAUP) and Bayesian inference (MrBayes), whereas the three analyses showed that the genera Gymnodinium and Karenia are unresolved groups in phylogeny. Minor sequence divergence was found within the different clones of Amphidinium carterae, suggesting that the ITS regions are suitable as genus- and species-specific oligonucleotide probes to rapidly detect and identify the red tide-forming algal species.Communicated by O. Kinne, Oldendorf/Luhe     

Effects of road dust on the growth characteristics of Sophora japonica L. seedlings

Road dust is one of the most common pollutants and causes a series of negative effects on plant physiology. Dust's impacts on plants can be regarded as a combination of load,composition and grain size impacts on plants; however, there is a lack of integrated dust effect studies involving these three aspects. In our study, Sophora japonica seedlings were artificially dusted with road dust collected from the road surface of Beijing so that we could study the impacts of this dust on nitrogen/carbon allocation, biomass allocation and photosynthetic pigments from the three aspects of composition, load and grain size. The results showed that the growth characteristics of S. japonica seedlings were mostly influenced by dust composition and load. Leaf N, root–shoot ratio and chlorophyll a/b were significantly affected by dust composition and load; leaf C/N, shoot biomass, total chlorophyll and carotenoid were significantly affected by dust load; stem N and stem C/N were significantly affected by dust composition; while the dust grain size alone did not affect any of the growth characteristics. Road dust did influence the growth characteristics more extensively than loam. Therefore, a higher dust load could increase the differences between road dust and loam treatments. The elements in dust are well correlated to the shoot N, shoot C/N, and root–shoot ratio of S. japonica seedlings. This knowledge could benefit the management of urban green spaces.     

絮凝浓缩武汉市巡司河底淤泥的研究

目的研究武汉市巡司河底淤泥在不同无机絮凝剂及PAM的助凝作用下淤泥清浑分界面的沉降速率、淤泥浓缩比以及淤泥沉降指数的变化情况。方法采用实验研究的方法,对巡司河底淤泥进行沉降实验,并通过沉降分析找到最佳脱水效果的脱水剂。结果当淤泥质量分数为10%时,Ca(OH)2取得的絮凝脱水效果最好,Ca(OH)2投加比为5 g/L,PAM投加比为0.04 g/L时,淤泥清浑分界面的沉降速率最大可达到3.7 cm/min,淤泥浓缩比为3.94,淤泥沉降指数为24.9%。结论 Ca(OH)2和PAM对巡司河底淤泥的脱水有促进效果,淤泥在Ca(OH)2和PAM共同作用下先后经历了自由沉降、絮凝沉降、区域沉淀和压缩沉降。     

长沙市大气中总挥发性有机物分布特征、变化规律及污染对策研究

为调查长沙市大气中TVOC的分布特征及变化规律,研究其污染控制措施,按照相关标准和技术规范,在不同的功能区划和行政区划内合理布设12个监测点位,分季节采集样品,使用热脱附－气相色谱法进行检测,利用反距离权重插值和遥感解译等方法进行综合分析。结果表明：长沙市大气中苯与甲苯（ B／T）特征比值为0．58,汽车尾气是长沙市苯系物和TVOC的主要来源;长沙市不同的工业区TVOC浓度有显著差异,工业区合理布局,增加绿化面积,可以有效的降低TVOC浓度。     

中国环境污染损害鉴定评估研究进展

环境污染损害鉴定评估是新时代环保工作的重要领域,是公众对人体健康和生态环境安全提出的更高要求,也是环境司法案件审理公平合理的迫切需求.开展环境污染损害鉴定评估工作即可以使环境私益损害得到足额赔偿,有利于环境公益损害赔偿的推动,又能通过提高环境污染成本,促使企业和地方加大环保投入,从而降低环境污染突发事故风险.该文简要概述了环境污染损害鉴定评估的基本概念,并从其发展历程和存在问题等方面探讨中国环境污染损害鉴定评估的研究进展,最后对其未来发展进行展望.     

Investment Risks of Agricultural Listed Companies from Visual Angle of Natural Disasters

The essential feature of agriculture is the interweavement of natural reproduction and economic reproduction. In recent years, the natural disasters have become more frequent and badly affect the production management and investment benefits. This problem has been an important risk in managing agricultural listed companies and cannot be ignored. It is of great importance to evaluate and prevent the risks of the natural disasters to enhance the competitive ability and increase the profits of those listed companies, thereby keeping the sustainable development of agricultural companies.     

对苏南地区城市化过程中环境问题的思考

对苏南地区城市化的特征和城市化过程中出现的环境问题进行了分析，指出城市化发展的必由之路是实行可持续发展，提出了该地区为实现可持续发展必须做到５个协调     

Municipal solid waste management in Beijing City

This paper presents an overview of municipal solid waste (MSW) management in Beijing City. Beijing, the capital of China, has a land area of approximately 1368.32 km² with an urban population of about 13.33 million in 2006. Over the past three decades, MSW generation in Beijing City has increased tremendously from 1.04 million tons in 1978 to 4.134 million tons in 2006. The average generation rate of MSW in 2006 was 0.85 kg/capita/day. Food waste comprised 63.39%, followed by paper (11.07%), plastics (12.7%) and dust (5.78%). While all other wastes including tiles, textiles, glass, metals and wood accounted for less than 3%. Currently, 90% of MSW generated in Beijing is landfilled, 8% is incinerated and 2% is composted. Source separation collection, as a waste reduction method, has been carried out in a total of 2255 demonstration residential and commercial areas (covering about 4.7 million people) up to the end of 2007. Demonstration districts should be promoted over a wider range instead of demonstration communities. The capacity of transfer stations and treatment plants is an urgent problem as these sites are seriously overloaded. These problems should first be solved by constructing more sites and converting to new treatment technologies. Improvements in legislation, public education and the management of waste pickers are problematic issues which need to be addressed.     

化学污染的现状及研究热点

本文分析了全球和我国化学污染的现状.目前化学污染覆盖的范围不断扩大、新化学污染物质不断涌现并对自然界和人体造成潜在的和深层次的危害、化学污染成为危害公共安全重要因素、危险化学废物越境转移频繁.当前化学污染研究中的热点问题：环境内分泌干扰物、持久性有机污染物和二[口恶][口英]等的研究.