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831.
环境规制对中国工业绿色增长指数的影响   总被引:1,自引:0,他引:1  
为衡量工业增长对资源的消耗和环境的污染,本文构建了"工业绿色增长指数",并运用基于松弛测度的方向距离函数(SBMDDF)对2007-2011年中国30省(区、市)进行测算,根据得分将其分成高绿化度地区、中绿化度地区和低绿化度地区;采用面板数据模型测算了行政型、市场型和公众参与型这三种类型的环境规制对工业绿色增长指数的影响,同时考察技术创新、工业结构对工业绿色增长的作用程度。研究发现:东部地区的工业绿色增长指数高于中西部地区;行政型和市场型环境规制对工业绿色增长的作用显著,市场型环境规制在高、中绿化度地区起主要作用,而低绿化度地区以行政型环境规制为主;公众参与型环境规制对工业绿色增长的作用有限;技术创新和工业结构也是影响工业绿色增长的重要因素。为促进工业绿色发展,中西部地区要树立绿色、低碳的理念对东部地区所转移的产业进行选择;高绿化度地区需在提高排污费标准的同时,逐步采用排污权交易等方式加大对环境污染总量的控制力度;低绿化度地区可在实行低标准排污费政策的同时,逐步实现从行政型向市场型环境规制的转变;逐步发挥并扩大公众参与型环境规制的作用;注重与节能减排相关的技术吸收和应用推广,降低高载能行业的比重。  相似文献   
832.
This paper established an equilibrium model including representative household, government, and eight industries, and two different environmental policy tools such as carbon intensity and carbon cap were added into the model. The paper points out that the carbon intensity policy imposed on major high-emission industries achieved double dividend of environmental-quality improvement and sustainable economic growth under the condition of proper constraint target. This result supports the environmental Porter hypothesis. This paper finds out that the double dividend is due to the fact that environmental governance policy leads to the rising price of resources and demand of labors, resulting in an effective redistribution of production factors among industries and sustainable economic growth. Furthermore, this paper estimates the marginal effect of economic structure on carbon emission and carbon intensity and provides targeted suggestions.  相似文献   
833.
唐青青  方治国  嵇雯雯  夏会龙 《环境科学》2014,35(11):4212-4217
采用发光二极管(light emitting diode,LED)调制光谱,研究了不同光质(红光、蓝光、白光、红蓝混光8∶1,红蓝混光8∶2,红蓝混光8∶3)对蛋白核小球藻(Chlorella pyrenoidosa)生长特性及生化组成的影响.结果表明,蓝光下蛋白核小球藻生长效果最佳,其接种后培养30 d,光密度为2.4,比生长速率为0.10 d-1,生物量为0.64 g·L-1,而其它光质下光密度、比生长速率和生物量分别在1.0~1.7、0.07~0.10 d-1和0.27~0.38 g·L-1之间,蓝光条件下其光密度、比生长速率和生物量分别约为红光下的2.05倍、1.33倍和2.06倍;红蓝混光有利于蛋白核小球藻叶绿素a和β-胡萝卜素的合成,蓝光可促进叶绿素b的合成,红蓝混光8∶1其叶绿素a和β-胡萝卜素的含量分别为13.5 mg·g-1和5.8 mg·g-1,而蓝光下分别为8.4 mg·g-1和3.6mg·g-1;红蓝混光更有利于蛋白核小球藻单位细胞干重蛋白质和总脂的积累,红蓝8∶3蛋白质含量为489.3 mg·g-1,红蓝8∶1总脂含量为311.2 mg·g-1,而蓝光下蛋白质和总脂含量均较低,分别为400.9 mg·g-1和231.9 mg·g-1.  相似文献   
834.
污水处理厂二级出水中四环素抗性菌的生长特性与耐药性   总被引:1,自引:0,他引:1  
抗生素抗性菌的扩散已成为全世界面临的重要公共卫生安全隐患.本文从某城市污水处理厂二级出水中分离出21株四环素抗性菌,对其种属、生理生化特性、抗生素耐受性进行了研究.结果表明,21株四环素抗性菌均属于肠杆菌科,分别属于气单胞菌属(9株)、埃希氏菌属(5株)、肠杆菌属(3株)、克雷伯氏菌属(2株)、柠檬酸杆菌属(1株)和哈夫尼菌属(1株).这些菌大多属于条件致病菌,且有18株携带质粒.21株四环素抗性菌中,气单胞菌、埃希氏菌的平均最大生长量显著高于肠杆菌,大部分菌株的迟滞时间在2 h以内.抗生素耐受性试验结果表明,四环素抗性菌对氯霉素耐受能力最强,对β-内酰胺酶类抗生素(青霉素、氨苄青霉素、头孢噻吩)的耐受性次之,对利福平的耐受性最弱.75%以上的四环素抗性菌同时表现出对其它5种抗生素具有抗性.以上结果为我国污水处理厂抗生素抗性菌的风险分析与控制提供了参考数据.  相似文献   
835.
The strategy of choosing suitable plants should receive great performance in phytoremediation of surface water polluted by triazophos(O,O-diethyl-O-(1-phenyl-1,2,4-triazol-3-base) sulfur phosphate, TAP), which is an organophosphorus pesticide widespread applied for agriculture in China and moderately toxic to higher animal and fish. The tolerance, uptake, transformation and removal of TAP by twelve species of macrophytes were examined in a hydroponic system and a comprehensive score(CS) of five parameters(relative growth rate(RGR), biomass, root/shoot ratio, removal capacity(RC), and bio-concentration factor(BCF)) by factor analysis was employed to screen the potential macrophyte species for TAP phytoremediation. The results showed that Thalia dealbata, Cyperus alternifolius, Canna indica and Acorus calamus had higher RGR values, indicating these four species having stronger growth capacity under TAP stress. The higher RC loading in Iris pseudacorus and Cyperus rotundus were 42.11 and 24.63 μg/(g fw·day), respectively. The highest values of BCF occurred in A. calamus(1.17), and TF occurred in Eichhornia crassipes(2.14). Biomass and root/shoot ratio of plant showed significant positive correlation with first-order kinetic constant of TAP removal in the hydroponic system, indicating that plant biomass and root system play important roles in remediation of TAP. Five plant species including C. alternifolius, A. calamus, T. dealbata, C. indica and Typha orientalis, which owned higher CS, would be potential species for TAP phytoremediation of contaminated water bodies.  相似文献   
836.
Water biostability is of particular concern to water supply as a major limiting factor for heterotrophic bacterial growth in water distribution systems. This study focused on bacterial growth dynamics in the series dilution of water samples with TOC(total organic carbon) values determined beforehand. The results showed that the specific growth rate of Pseudomonas fluorescens P17 varied dramatically and irregularly with TOC value when TOC concentrations were low enough during the initial periods of incubation under given conditions. According to this relationship between bacterial growth rate and TOC, a dilution incubation method was designed for the study of water biostability. With the method under a given condition, a turning-point TOC value was found at a relatively fixed point in the curve between bacterial growth rate and TOC of water sample, and the variation of growth rate had different characteristics below the turning-point TOC value relative to that over this value. A turning-point TOC value similarly existed in all experiments not only with tap water, but also with acetate and mixed solutions. And in the dilution incubation method study, the affections were analyzed by condition factors such as inoculum amount,incubation time and nature of the organic carbon source. In very low organic carbon water environments, the variation characteristics of bacterial growth rate will be useful to further understand the meaning of water biostability.  相似文献   
837.
湖泊底质对根着水生植物生长发育有重要的影响,通过滨岸底质植生性改良、重建水生植被被认为是污染湖泊生态修复的重要手段.本研究模拟5种客土厚度对芦苇生长和叶绿素荧光参数的影响,结果表明,覆盖5 cm处理芦苇总生物量、株高、叶长和叶宽显著大于覆盖18 cm处理(P0.01),实验第120 d,地下/地上部生物量和细根/地下部生物量显著大于其他处理(P0.05).表明覆盖18 cm显著抑制芦苇生长,但对照组富营养底质可能对芦苇生长造成轻微胁迫,随覆盖厚度增大,显著降低芦苇的地下部/地上部生物量比值,芦苇优先生长地下部,特别是细根的生物量,以便从底质中吸收更多养分供植物生长.不同处理芦苇F_v/F_m、Yield、q P和q N变化差异不显著(P0.05),覆盖厚度越大,芦苇光合结构PSⅡ更易受到损坏,主要是通过较高的热耗散、降低叶片光合面积与叶片捕光色素含量来维持光合结构PSⅡ保持正常.就客土改良对芦苇生长与叶绿素荧光参数总体影响而言,覆盖2 cm和5 cm能有效改善基质Eh和营养条件,促进植物生长,其中覆盖2 cm处理能有效地提高芦苇光合利用效率(α)、相对电子传递速率(ETRmax)和半饱和光强(E_k),覆盖18 cm使得芦苇对冬季的低光抑制有更强的适应能力.  相似文献   
838.
The conversion of natural habitat to urban settlements is a primary driver of biodiversity loss, and species' persistence is threatened by the extent, location, and spatial pattern of development. Urban growth models are widely used to anticipate future development and to inform conservation management, but the source of spatial input to these models may contribute to uncertainty in their predictions. We compared two sources of historic urban maps, used as input for model calibration, to determine how differences in definition and scale of urban extent affect the resulting spatial predictions from a widely used urban growth model for San Diego County, CA under three conservation scenarios. The results showed that rate, extent, and spatial pattern of predicted urban development, and associated habitat loss, may vary substantially depending on the source of input data, regardless of how much land is excluded from development. Although the datasets we compared both represented urban land, different types of land use/land cover included in the definition of urban land and different minimum mapping units contributed to the discrepancies. Varying temporal resolution of the input datasets also contributed to differences in projected rates of development. Differential predicted impacts to vegetation types illustrate how the choice of spatial input data may lead to different conclusions relative to conservation. Although the study cannot reveal whether one dataset is better than another, modelers should carefully consider that geographical reality can be represented differently, and should carefully choose the definition and scale of their data to fit their research objectives.  相似文献   
839.
本研究从某农药厂污水处理池的活性污泥中分离得到1株能以乙羧氟草醚为唯一碳源生长的菌株。经生理生化鉴定和16SrRNA基因序列同源性分析,将此菌株初步鉴定为腐生葡萄球茵(Staphylococcussaprophyticus),并命名为YSC.1。对菌株YSC.1的生长特性研究表明:茵株的最佳生长温度和pH分别为30℃、7.0;NaCI浓度对菌株YSC-1生长有较大的影响。菌株在20℃-40℃之间均能降解乙羧氟草醚,在30%1、pH7.0的条件下对乙羧氟草醚的降解率最高;增加乙羧氟草醚的浓度会对菌株产生毒害作用,降低其降解率;提高接种量可以加快乙羧氟草醚的降解。在乙羧氟草醚终浓度为100mg/L的工业废水经7d处理后,乙羧氟草醚的去除率达91.62%,说明菌株YSC-1在废水处理中具有很好的应用前景。  相似文献   
840.
One of the key problems confronting ecological forecasting is the validation of computer models. Here we report successful validation of a forest dynamics model Ecosystem Dynamics Simulator (EDS), adapted from the JABOWA-II forest succession model. This model and many variants derived from it have successfully simulated growth dynamics of uneven-aged mixed forests under changing environment with a moderate amount of input data. But rarely are adequate time-series data available for quantitative model validation. This study tested the performance of EDS in projecting the tree density, tree diameter at breast height (dbh), tree height, basal area and aboveground biomass of uneven-aged, mixed species sclerophyll forests in St. Mary state forests of eastern Australia. The test data were collected between 1951 and 2005. Every tree was uniquely numbered, tagged and measured in consecutive re-measurements. Projected growth attributes were compared with those observed in an independent validation dataset. The model produced satisfactory projections of tree density (91.7%), dbh (92.3%), total tree height (82.8%), basal area (89.3%) and aboveground biomass (87.6%) compared to the observed attributes. These results suggest that the EDS model can provide reasonable capability in projecting growth dynamics of uneven-aged, mixed species sclerophyll forests.  相似文献   
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