黄河三角洲旅游环境承载力研究

旅游业发展应注重生态和社会经济的协调有序,生态旅游兼顾区域经济发展和生态保护,符合高效生态经济发展战略,是黄河三角洲高效生态经济区产业结构的重要组成部分,然而高效生态经济区旅游业起步晚、发展滞缓;同时,脆弱的生态环境以及围垦开发活动使得该区域在旅游开发和旅游活动中生态保护的重要性尤为突出。通过建立包含湿地生态指标的多层次旅游环境承载力评价指标体系,依托最小限制因子法,评估生态、空间、设施和社会环境容量及承载力,判识旅游环境容量的主要限制因子,以期诊断影响研究区旅游环境承载力的主要问题。结果表明：1)黄河三角洲高效生态经济区旅游环境日容量由1995年的-288.57万人升至2020年的11.60万人,但旅游环境承载力仍为严重超载;2)1995,2020年的最小限制因子分别为污水处理和交通设施,且仅有这2个指标超载,其他指标均为弱载,所有指标均不适载;3)1995年旅游环境承载力主要受限于生态环境容量,而2020年旅游环境容量二级指标顺序为空间>社会>生态>设施;4)目前,旅游设施超载,而包括湿地生态指标在内的生态环境和空间环境均弱载,服务供给不足以支撑旅游资源的充分利用...     

基于灰色关联与主成分分析的环境承载力评价

以广西为例,基于区域系统论的视角,从社会系统、资源系统和环境系统子系统选取21个指标构建环境承载力评价指标体系,以层次分析法确定指标权重,采用灰色关联法对2005-2014年广西环境承载力状况进行量化测度和系统分析,利用主成分分析法对承载力结果验证分析。结果表明:(1)从时序变化上看,2005-2014年,关联度由62.43提高至92.35,广西承载力水平逐年提高,高速发展的社会经济是环境承载力的最直接驱动力。(2)主成分分析法因剔除部分信息故导致评价结果波动大,灰色关联法评价结果稳定且差距小,但两者反映的趋势和结论是一致的,说明评价结果精度较好。(3)通过环境系统短板因子分析,水环境质量良好且逐年改善,固废指数呈"低-高-低"态势,大气污染成为阻碍广西环境治理的关键。     

沿海城市碳承载力研究——以青岛市为例

在构建沿海城市碳承载力评价指标体系的基础上,采用熵权法为指标赋权,构建了沿海城市碳承载力模型,并按照其取值范围将沿海城市碳承载水平划分为严重空载、轻度空载、适载、轻度超载和严重超载五个级别。利用所建模型和2000～2009年数据对青岛市碳承载状况进行了分析,研究表明:近几年来青岛市碳承载力状况良好,且2009年青岛市碳承载力为0.9左右,整体处于较为理想的适载状态。影响青岛市碳承载状况的主要因素包括经济增长、环境、能源、产业结构、城市化等方面。青岛市建立低碳发展模式降低碳排放,维持碳承载平衡应从调整产业结构、转变经济发展方式、建立低碳发展的长效机制、保护资源环境、大力开发新能源、发展低碳旅游业和进一步完善区域性碳承载力理论体系等方面努力。     

广西沿海重要海湾环境承载力评估

以广西沿海的珍珠港、防城港、廉州湾、钦州湾、铁山港5个海湾为例,通过剖析环境承载力的内涵,根据海洋环境的生态服务功能,构建了海洋环境承载力的评估指标体系。从定量表达和评估应用需求出发,构建了基于模法的海洋环境承载力评价模型。根据广西沿海2006～2007年908调查资料,计算了各重要海湾的环境承载力。     

武夷山世界遗产地旅游环境承载力研究

以旅游环境承载力理论为基础,初步构建了武夷山风景区的旅游环境承载力指标体系。通过问卷调查、专家访谈及相关资料的分析,对各分量旅游环境承栽力进行测算,得出：景区的限制因子为经济旅游环境承载力,景区的适宜承载力为8000人次／日,极限承载力为9600人次／日;武夷山景区旅游环境承载力利用现状为全年弱载,旺季超载,旺季高峰日严重超载,旅游淡季适载;景区各景点承载力利用水平不同,游客多聚集在九曲溪、天游-云窝景区。在旅游环境承载力测算的基础上,提出时空分流、加大对外的宣传、新增游览线路等调控措施解决景区超载和弱载问题．为武奏山世界遗产地可持续发展提供了科学依据．     

基于熵权模糊物元的辽宁省生态环境承载力研究

生态环境质量的下降影响着辽宁省社会经济的可持续发展。综合分析辽宁省生态环境的特点,选取18项指标,构建辽宁省生态环境承载力的评价指标体系,并划分各评价指标的等级。从近15年中选取8年的数据作为研究对象,构建熵权模糊物元模型,计算各评价指标的客观权重,并应用加权欧式距离对这8年生态环境的承载力水平做出评价。分析评价结果可知：辽宁省近15年生态环境承载力水平从“一般”转变为“较好”,整体水平提高。结果与辽宁省实际情况相符,证明了熵权模糊物元模型在评价问题上的可行性和合理性。最后为辽宁省生态环境的可持续开发利用提供了一些建议。     

工业园区规划环境影响评价中的环境承载力方法研究

环境承载力是区域规划环境影响评价的重要依据,可为区域发展适度规模提供环境支撑依据.针对工业园区生态环境特征,以珠海富山工业园为案例建立环境承载力评价指标体系,并结合该指标开发基于熵值法的工业园区环境承载力动态评价模型,模拟珠海富山工业园区规划情景下的环境承载力变化.结果表明,工业园区环境承载力于规划中后期处于下降趋势,但下降的趋势较为缓和;园区发展压力伴随着园区规划建设处于下降趋势,规划建设初期的下降趋势最为明显.通过灰色关联度分析发现,规划期园区经济社会发展始终处于园区资源环境的可承载范围,随着园区进一步发展、科学技术水平提高和基础设施完善,园区综合环境承载力可提升至较为稳定的水平.     

基于DPSIR-TOPSIS模型的福建省生态环境承载力评价及障碍因素研究

生态环境承载力是生态文明建设的基础,研究生态环境承载力对于深入实施生态文明建设具有重要意义.福建省在生态文明建设方面走在全国前列,通过研究福建省的生态环境承载力情况,有助于更好地推进福建省生态文明建设.基于DPSIR概念模型构建了福建省生态环境承载力评价指标体系,采用TOPSIS分析法和障碍度模型对福建省2000—2015年生态环境承载力状况和障碍因子进行了评价分析.结果表明:总体而言,福建省生态环境承载力综合贴近度不断上升,从2000年的0.09981上升到2015年的0.89625,表明福建省生态环境承载力水平稳步提升;从分类指标来看,驱动力、状态、影响和响应子系统评价指数均呈不同幅度的上升趋势,而压力子系统评价指数呈下降趋势,表明福建省在生态环境治理方面所做的努力是卓有成效的,生态文明建设压力相对减小;从障碍度分析来看,就分类指标而言,响应子系统承载力是影响福建省生态环境承载力的主要因素系统.就主要障碍因素而言,在研究期内,影响福建省生态环境承载力的主要障碍因素包括能源消耗弹性系数、城市环境基础设施投资、环境保护投资占GDP的比例等.基于上述结论,本研究最后提出了相应的对策措施.     

区域生态承载力综合评价及分析——以云南省易门县为例

基于生态压力、生态弹性力及社会生态发展水平之间的相互作用关系,利用综合评价法构建生态承载力评价指标体系,研究区域生态承载力水平,采用主成分分析法对指标进行赋权并求解易门县生态承载力水平。针对易门县主要的生态环境问题利用GIS技术并结合相关数据,对该区域矿产资源承载力、耕地承载力和森林承载力进行计算。结果显示:2005—2013年,易门县的生态承载力水平呈现先增大后减小的趋势,并在2010年恶化为超载,但是社会生态发展水平保持持续增长的态势。2015年易门县的铜矿可承载的经济能力为1200.932亿元,保证年限为23.829a;最大允许耕地面积为13100.752km2;适合天然林生长的生境面积为135470.780km2。     

基于模糊综合评判的辽宁省海域承载力研究

借鉴有关承载力的研究成果,利用模糊综合评判方法对辽宁省海域承载力进行了评价分析。结果表明:1999至2009年间,除2000年,辽宁省的海域承载力数值均处于适载范围,但是由于其数值绝大多数都在0.34～0.40之间浮动,因此辽宁省的海域承载能力为中等偏弱。过度捕捞、环境污染、环境治理能力和科技发展水平等因素的影响是辽宁省海域承载力中等偏弱的主要因素,基于此提出了改善辽宁省海域承载力的对策建议。     

Distribution and ecological effect of mercury in Laogang landfill, Shanghai, China

Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury （HgT）, combinative mercury （Hgc） and gaseous mercury （HgG）, and content of total organic carbon （TOC）, but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of （HgG,/HgT）1992〉（HgG/HgT）1996〉〉（HgG/HgT）2000. A simple outline of Hg release in landfill could be drawn： with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants （e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum） are capable of enriching more Hg than herbaceous plants.     

EDTA-enhanced phytoremediation of lead contaminated soil by Bidens maximowicziana

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.     

Decomposition of alachlor by ozonation and its mechanism

Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.     

Enzymatic oxidation of aqueous pentachlorophenol

The influence of the nonionic surfactant Tween 80 on pentachlorophenol （PCP） oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.     

基于综合水质标识指数和对应分析法的校园河道水质评价

以三峡大学的校园河道求索溪为研究对象,利用综合水质标识指数法确定求索溪水质类别,分析其水质时空变化规律,并利用对应分析法得出求索溪中不同监测点的主要污染因子.研究结果表明:求索溪整体的综合水质标识指数为7.423,整体水质为劣V类(地表水环境质量标准GB 3838-2002)且黑臭.从时间变化来看,求索溪4月份的水质最差,5月份次之,4、5月份所有监测点的水质都劣于V类且黑臭;8月份水质最好,水质为Ⅳ类;从空间分布来看,8个监测点综合水质标识指数均超过6.0,水质为劣V类,其中6号监测点的水质相对最好,监测点3号的水质相对最差;对应分析法得出求索溪的整体水体污染程度受总氮因子的影响最大,其次为总磷.该研究拟为求索溪及类似校园河道的水环境治理研究提供基础依据和参考.     

Effects of chitosan on growth of an aquatic plant (Hydrilla verticillata) in polluted waters with different chemical oxygen demands

Effects of chitosan on a submersed plant, Hydrilla verticillata, were investigated. Results indicated that H. venicillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand (COD). Superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD (980 mg/L) and decreased with low COD (63 mg/L), respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant cells from the control experiment (untreated with chitosan) were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.     

Removal of cadmium using MnO2 loaded D301 resin

MnO2 loaded weak basic anion exchange resin D301 （Anion exchange resin, macroreticular weak basic styrene） as adsorbent has been prepared and applied to the removal of cadmium. The adsorption characteristics have been investigated with respect to effect of pH, equilibrium isotherms, removal kinetic data, and interference of the coexisting ions. The results indicated that the Cd^2＋ could be efficiently removed using MnO2 loaded D301 resin in the pH range of 3-8 from aqueous solutions with the co-existence of high concentration of alkali and alkaline-earth metals ions. The saturate adsorption capacity of the Cd^2＋ was 77.88 mg/g. The adsorption process followed the pseudo first-order kinetics. The equilibrium data obtained in this study accorded excellently with the Langmuir adsorption isotherm.     

Effect of coagulation pretreatment on the fouling of ultrafiltration membrane

The purpose of this study is to understand the effect and mechanism of preventing membrane fouling, by coagulation pretreatment, in terms of fractional component and molecular weight of natural organic matter （NOM）. A relatively higher molecular weight （MW） of hydrophobic compounds was responsible for a rapid decline in the ultrafiltration flux. Coagulation could effectively remove the hydrophobic organics, resulting in the increase of flux. It was found that a lower MW of neutral hydrophilic compounds, which could remove inadequately by coagulation, was responsible for the slow declining flux. The fluxes in the filtration of coagulated water and supernatant water were compared and the results showed that a lower MW of neutral hydrophilic compounds remained in the supernatant water after coagulation could be rejected by a membrane, resulting in fouling. It was also found that the coagulated flocs could absorb neutral hydrophilic compounds effectively. Therefore, with the coagulated flocs formed on the membrane surface, the flux decline could be improved.     

Penetration analysis of elements and bioleaching treatment of spent refractory for recycling

Acidithiobacillus ferrooxidans ATCC23270 and Acidithiobacillus thiooxidans TM-32 were used for bioleaching of spent refractories of aluminium and copper melting furnaces for their recycling.Firstly,penetration of elements into aluminium melting furnace refractory was investigated and it was found that up to 7 cm from surface was contaminated.Comparison on leaching efficiency by the strains ATCC23270 and TM-32 found that the strain ATCC23270 could treat larger amount of the refractories than the strain TM-32 could do.In the experiment of bioleaching of spent refractory aluminium melting furnace by the strain ATCC23270,high leaching efficiency were obtained on Al,Si,and Ca,and extremely low leaching performance was,however,shown on the rest of elements i.e.,Na,Mn,and Zn.Under the strain TM-32 use,relatively high leaching performance was recognized on Al,Si,Ca,Na,Mn,and Zn.In the experiment of bioleaching for spent refractory copper melting furnace,almost the same leaching trends were shown on Cu,Zn,Al,and Si under the strains ACTT23270 and TM-32 uses.     

Simultaneous removal of ammonium and phosphate by zeolite synthesized from coal fly ash as influenced by acid treatment

Zeolite synthesized from fly ash （ZFA） without modification is not efficient for the purification of NH4＋ and phosphate at low concentrations that occur in real effluents, despite the high potential removal capacity. To develop an effective technique to enhance the removal efficiency of ammonium and phosphate at low concentrations, ZFA was modified with acid treatment and the simultaneous removal of ammonium and phosphate in a wide range of concentration was investigated. It was seen that when compared with untreated ZFA, only the treatment by 0.01 mol/L of H2SO4 significantly improved the removal efficiency of ammonium at low initial concentrations. The behavior was well explained by the pH effect. Treatment by more concentrated H2SO4 led to the deterioration of the ZFA structure and a decrease in the cation exchange capacity. Treatment by 0.01 mol/L H2SO4 improved the removal efficiency of phosphate by ZFA at all initial P concentrations, while the treatment by concentrated H2SO4 （≥0.9 mol/L） resulted in a limited maximum phosphate immobilization capacity （PIC）. It was concluded that through a previous mild acid treatment （e.g. 0.01 mol/L of H2SO4）, ZFA can be used in the simultaneous removal of NH4＋ and P at low concentrations simulating real effluent.