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1.
从蓝绿藻中选取绿藻门的普通小球藻(Chlorella vulgaris,CV藻)为研究对象,应用Monod方程考察氮、磷营养盐对CV藻生长的影响,分别计算出CV藻对TP、TN的半饱和常数KSP和KSN结果表明KSN>>KSP,说明TP对CV藻生长的影响明显大于TN.CV藻生长速率对磷质量浓度反应很灵敏:与空白值相比,在0.002 mg·L-1的低浓度下u就有提高,而浓度到0.2 mg.L-1时,u明显增大;但在0.000-0.050 mg·L-1氮浓度范围内u几乎没有变化.通过系统比较CV藻与优势蓝绿藻,甚至海水藻的生长动力学特征,探讨了CV藻与其它蓝绿藻的动力学普适性和共同性,证实这些藻类都具有非常类似的生长动力学和生态学特征.因此,推测CV藻生长动力学模型可以从整体上反映和代表库区优势蓝绿藻的生长行为.同时分析和归纳了蓝绿藻生长模型的相似性和规律性,得出三峡库区优势藻类生长行为存在普遍一致性的初步结论. 相似文献
2.
Urban forest is a very important part of urban ecosystems and provides significant ecosystem services. It benefits urban communities environmentally, aesthetically, recreationally and economically. This article reviews the development status, development patterns and influencing factors of urban forest in China. There are four typical development patterns of urban forest in China: the forest city, garden city, ecological economics and forest greenbelt. Social, climatic, economic and other factors influence urban forest development in China. Social factors include government behaviour, laws and regulations, science and technology, education and culture, public awareness and participation, ecological planning and management. Climatic factors include rainfall, temperature and sunlight. Economic factors include urban economic level and funding for urban forest. In future, government, NGOs and the private sector should be considered more in the planning and management of urban forest. The social, climatic and economic factors should be taken into account when improving urban forest management. Research on urban forest from the academic and the management viewpoint should be strengthened. This can improve the development and management of urban forest in China and in other developing countries. 相似文献
3.
以斑马鱼(Danio rerio)为受试动物,研究了四种环境雌激素-17β-雌二醇(E2)和三种增塑剂(DMP、DBP、DOP)对其内脏团的氧化损伤及应激效应。经急性毒性实验,得到E2、DMP、DBP、DOP对成体斑马鱼96 h的半数致死浓度(LC50)分别为2.51、12.33、9.67、9.89 mg·L-1。在此基础上分别设置5个浓度梯度,研究E2(暴露2 d,4 d)、DMP、DBP、DOP(暴露4 d)对斑马鱼内脏团的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽硫转移酶(GST)活性以及丙二醛(MDA)含量的影响。结果表明,SOD、CAT、GST、MDA对这四种环境激素都非常敏感,其中SOD、CAT、GST活性的影响均呈现先诱导后抑制的趋势,而MDA含量则随着污染物浓度的升高而增加。高浓度暴露条件下,E2(0.4 mg·L-1)和DMP、DBP、DOP(0.8 mg·L-1)对SOD、CAT、GST活性均有显著抑制(p0.05),MDA的含量有显著升高(p0.05)。可见,E2、DMP、DBP、DOP会导致斑马鱼内脏团氧化损伤,并且在同等浓度下E2的毒性明显高于三种增塑剂。 相似文献
4.
以大庆东城污水处理厂进水为实验原水,采用化学混凝-两级曝气生物滤池(BAF)组合工艺进行现场中试研究(12 m3/d),重点考察了在化学混凝的强化作用下,曝气生物滤池工艺对低温城市污水中有机物、氮和磷等污染物的净化效能。实验结果表明,单独采用两级曝气生物滤池工艺,当原水COD、NH3-N、TN和TP的平均浓度分别为450、45、60和6 mg/L左右时,曝气生物滤池可在25 d内完成挂膜;系统运行稳定后,常温条件下(>10℃)COD、NH3-N、TN和TP的平均去除率分别为94.3%、97.5%、77.71%和95.6%;低温条件下(6~10℃),采用化学混凝两级BAF组合工艺时,在混凝剂硫酸铝投量为25~30 mg/L条件下,组合工艺出水的COD、NH3-N、TN和TP平均浓度分别为45.2、3.26、12.56和0.43 mg/L,满足《城镇污水处理厂污染物排放标准》(GB18918-2002)中一级A排放要求。 相似文献
5.
Ming W. Song Ping Huang Feng Li Hui Zhang Kai Z. Xie Xi H. Wang Guo X. He 《Environmental monitoring and assessment》2011,172(1-4):589-603
Water quality information of Beijiang River, a tributary of Pearl River in Guangdong, China, was analyzed to provide an overview of the hydrochemical functioning of a major agricultural/rural area and an industrial/urban area. Eighteen water quality parameters were surveyed at 13 sites from 2005 to 2006 on a monthly basis. A bivariate correlation analysis was carried out to evaluate the regional correlations of the water quality parameters, while the principal component analysis (PCA) technique was used to extract the most influential variables for regional variations of river water quality. Six principal components were extracted in PCA which explained more than 78% and 84% of the total variance for agricultural/rural and industrial/urban areas, respectively. Physicochemical factor, organic pollution, sewage pollution, geogenic factor, agricultural nonpoint source pollution, and accumulated pesticide usage were identified as potential pollution sources for agricultural/rural area, whereas industrial wastewaters pollution, mineral pollution, geogenic factor, urban sewage pollution, chemical industrial pollution, and water traffic pollution were the latent pollution sources for industrial/urban area. A multivariate linear regression of absolute principal component scores (MLR-APCS) technique was used to estimate contributions of all identified pollution sources to each water quality parameter. High coefficients of determination of the regression equations suggested that the MLR-APCS model was applicable for estimation of sources of most water quality parameters in the Beijiang River Basin. 相似文献
6.
As a carrier to develop various marine resources, sea area is regulated as a kind of important resources through legislation by many coastal countries with a management system for the paid use of sea area. Since the early 1990s, China has begun to implement the paid use and formed an institutional system comprised of three levels after developing it for more than two decades. From 2002 to 2015, the Chinese Government transferred the use right of sea area of 33,910 km2 by paid use and levied a total of 75.89 billion CNY (11.328 billion US dollars) of sea area use payment. Apart from this, the Government has gained rich experience in operating and managing the compensable use of sea area. After retrospectively analyzing the development history of paid use of China’s sea area, the research presents an institutional structure and the implementation of the management system for the paid use of sea area and the main problems therein. On this basis, management policies and feasible policy suggestions are proposed. Research results from this study can provide available references for other developing countries and emerging economies to apply and improve native management system for the paid use of sea area. 相似文献
7.
Liu Z He Y Li F Liu Y 《Environmental science and pollution research international》2006,13(5):328-332
Background, Aim and Scope
The polynitramines, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX),
are important military explosives and regulated toxic hazardous compounds. Production, testing and use of the compounds has
resulted in numerous acres of contaminated soils and groundwater near many munitions facilities. Economical and efficient
methods for treatment of wastewater and cleanup of soils or groundwater containing RDX and HMX are needed. This study focuses
on the photocatalytic treatment of RDX wastewater with nano-sized titanium dioxide (nano-TiO2) under simulated sunlight, whose
intensity and wavelength are similar to that of the real sunlight in Xi'an at noon. The objective is to determine the potential
for RDX destruction with nano-TiO2 in aqueous solution.
Materials and Methods:
An activated carbon fiber (ACF) cloth-loaded with nano-TiO2 was put into the RDX containing solution, and the concentration
of RDX was measured (by HPLC–UV) at regular time intervals under simulated sunlight.
Results:
The RDX degradation percentage of the photocatalytic process is higher than that of Fenton oxidation before 80 min, equivalent
after 80 min, and it reaches 95% or above after 120 min. The nano-TiO2 catalyst can be used repeatedly.
Discussion:
The photocatalytic degradation kinetics of RDX under simulated sunlight can be described by a first-order reaction kinetics
equation. The possible degradation mechanism of RDX was presented and the degradation performance was compared with that of
biological method.
Conclusions:
It was demonstrated that the degradation of RDX wastewater is very effective with nano-TiO2 as the photocatalytic catalyst
under simulated sunlight. The efficiency of the nano-TiO2 catalyst for RDX degradation under simulated sunlight is nearly
identical to that of Fenton oxidation.
Recommendations and Perspectives:
To date, a number of catalysts show poor absorption and utilization of sunlight, and still need ultraviolet light irradiation
during wastewater degradation. The nano-TiO2 used in the described experiments features very good degradation of RDX under
simulated sunlight, and the manufacturing costs are rather low (around 10 Euro/m2). Moreover, the degradation efficiency is
higher compared to that of the biological method.
This method exhibits great potential for practical applications owing to its easiness and low cost. If it can be applied extensively,
the efficiency of wastewater treatment will be enhanced greatly. 相似文献
8.
大众心理因素对环保理念的推广表现为人的心理与环保行为之间的关系问题,是人类生态学和环境生理学研究的范畴。大众对环保心理的认知程度和接受程度对环保意识的形成和整个社会环保理念的推广具有促进性作用。通过环保宣传和环保教育,在大众中培养自觉环保意识,大众通过环境保护教育提高对环境污染防治和环境保护的心理认知,自觉形成环保理念,形成环保的行动自觉。通过环境心理因素引导,培养大众的环保科学文化知识,让大众将环保关注点放在具体的实际生活和工作问题上,并引导大众从身边生活的细节出发,做一位爱护环境的公民。 相似文献
9.
QuantitativemodelforspeciesdistributionofhydroxypolyaluminumchlorideFengLi,LuanZhaokun,TangHongxiaoResearchCenterforEcoEnvir... 相似文献
10.