呼和浩特资源-环境-经济承载和协调发展研究

为保持城市发展与城市承载间的动态平衡关系,揭示地区承载现状及演变规律,实现可持续发展,文章从自然资源、生态环境、经济社会三维度构建城市综合承载力指标集,以内蒙古和全国为参照对象,对呼和浩特市承载力水平动态演进和系统耦合协调度进行全面测评,运用PSO优化下的LSSVM模型对呼和浩特人口、承载力进行预测。结果表明:(1)2006-2017年呼和浩特承载力处于富裕状态;(2)三系统协调耦合度呈持续上升态势,2017年协调耦合度为0.86,已处于基本协调层级;(3)呼和浩特市未来人口与城市承载力将维持在相对富裕平稳的状态;(4)自然资源子系统是制约城市承载力有效提升和全面协调发展的主要原因;(5)耕地、水资源和城市绿地面积是阻碍呼和浩特承载力提升的关键因素。呼和浩特市承载力持续向好,高质量发展迈出坚实步伐,但内部支撑要素短板突出,需积极出台相关政策措施进一步提升城市承载容量。     

杭州城市化与水环境的耦合协调发展研究

城市化与水环境的同步发展对城市化质量提升意义重大。文章通过构建耦合协调发展模型,并利用杭州市2000—2013年的相关数据,分析研究了杭州市城市化与水环境的耦合协调发展情况。研究表明杭州市城市发展迅速,但水环境发展非同步,因此耦合度不高,且耦合协调度显示两者发展处于低度协调向一般协调的转换过程中,耦合度和耦合协调度呈现一定的分异特征。最后就城市化和水环境的均衡发展提出相应建议。     

辽宁沿海地区用水效率与经济的耦合协调发展评价

论文构建辽宁沿海经济带用水效率与经济耦合协调发展评价指标体系,首先运用改进的突变模型对2001—2010 年辽宁沿海经济带用水效率和经济发展各子系统进行状态评估,其次运用耦合协调模型对辽宁沿海经济带各市用水效率与经济发展的耦合协调度进行评价。研究结果表明：①辽宁沿海经济带整体用水效率与经济发展耦合度水平从0.437 提高到0.498,呈缓慢提高状态,但一直处于拮抗阶段。用水效率水平与经济发展水平差距不断减小,耦合协调度从0.254 增大到0.408,呈增大趋势但仍处于中低度协调水平;②辽宁沿海经济带各市用水效率与经济发展都处于上升趋势,其中用水效率最好的为大连市,用水效率评估值已达到0.887,其次为锦州、营口和葫芦岛,丹东和盘锦市用水效率处于最低水平,分别为0.604和0.535。经济发展水平最高的为大连市,其次为营口和盘锦市,丹东、锦州和葫芦岛较差; ③各市耦合度均处于拮抗阶段,并且处于上升趋势。大连市和营口市耦合协调度2010年已分别达到0.457 和0.401,已从低度协调进入中度协调且呈不断上升趋势,丹东、锦州、盘锦和葫芦岛均处于低度协调阶段,呈波动式上升。各市的经济发展滞后于水资源利用效率的提高,导致耦合协调度一直处于中低度协调水平;④辽宁沿海经济带耦合度和协调度的区域差距在不断减小,经济带协同发展趋势越加明显。     

中国西部地区水-能源-粮食系统耦合协调度的时空特征

在2005~2018年中国西部地区水-能源-粮食系统综合发展评价的基础上,运用耦合协调度模型和地理加权回归模型对水-能源-粮食系统耦合协调度的时空特征及其影响因素进行实证研究.结果表明:(1)中国西部水-能源-粮食系统及其各子系统的综合发展指数总体呈波动上升趋势,其中,水资源和能源子系统在2011年后长期滞后于粮食子系统,成为西部地区水-能源-粮食系统耦合协调发展的短板.(2)2005~2018年,中国西部水-能源-粮食系统耦合协调度从勉强耦合协调进入初级耦合协调阶段,且耦合协调度呈现“南高北低”的时空特征.(3)居民消费水平和人口规模对甘肃、内蒙古等西北地区的系统耦合协调度具有正向影响,对重庆、云南等西南地区具有负向影响,影响程度在地理空间上均呈现出“北正南负”的空间特征;地方财政环保投入的影响程度从北到南逐渐增大,广西、贵州、四川、陕西的系统耦合协调度受该因素的影响最大;R&D投入强度对系统耦合协调的推动作用相对较小,影响程度呈现“北高南低”的空间特征.基于上述分析结果,提出了多资源系统联合发展视角下的区域资源管理方式,减少对有限资源间的依赖性,改善人口规模及环保科技投入等因素,构建具有西部区域特色、体现资源优势、富有竞争力的水-能源-粮食系统耦合协调发展策略.     

城市化与生态环境耦合协调度评价研究——以济南市为例

以济南市为研究区域,利用2006年-2015年的统计数据,建立城市化与生态环境协调度评价指标体系,对济南市城市化与生态环境耦合协调关系进行分析与评价。结果表明:2006年-2015年期间,济南市城市化与生态环境耦合度处于拮抗阶段;2006年-2008年期间,城市化与生态环境耦合协调度处于严重不协调阶段,2009年-2015年期间,城市化与生态环境耦合协调度处于基本不协调阶段。正确认识城市化与区域生态环境耦合协调度特征,采取恰当的城市发展战略,改善生态环境,对区域可持续发展具有重要意义。     

城市综合应灾能力的耦合协调度评估

城市综合应灾能力能否在城市灾害过程中相互协调、互相配合,是衡量一座城市在未来是否能够可持续发展的重要指标。首先,在阐述城市综合应灾能力内部耦合关系的基础上,综合利用熵权法和耦合度理论,建立了能够量化城市综合应灾能力内部关联程度的耦合度模型;其次,利用耦合协调理论,建立了能够评价城市综合应灾能力协调程度的耦合协调度模型;最后,以某一城市为例,对2007—2018年该城市的综合应灾能力进行耦合度和耦合协调度评估。结果表明:2007—2018年该城市的综合应灾能力的耦合度一直处于高水平耦合状态,且其值波动幅度较小,说明该城市综合应灾能力内部各应灾子能力之间的关联程度极强;其耦合协调类型由最初的初级协调型发展成为良好协调型,且呈稳步上升趋势,说明该城市的综合应灾能力呈良好发展态势。     

熵权法在城市经济与环境耦合协调发展评价中的应用

运用熵权法和耦合协调度模型对城市经济与环境的协调发展情况进行评价。在建立经济和环境指标体系基础上,算出阿图什市经济与生态环境系统耦合协调度,并判别阿图什市的经济与环境的协调发展状态。研究结果表明:2010—2015年,阿图什市经济与环境的耦合度均高于0.75,平均值为0.892,高度耦合,协调度分别为0.573,0.611,0.668,0.755,0.630和0.735;2010年的系统协调状态为勉强协调型,其余年分均为中度协调型。研究期间经济与生态环境的耦合度类型,从经济滞后型转变为环境滞后型。熵权法与耦合协调度模型法混合应用判别城市协调发展情况计算步骤简单,结果合理,有一定的参考价值。     

成渝地区双城经济圈人口-经济-环境系统协调发展时空演化

人口、经济和环境协调发展是成渝地区双城经济圈协调发展及高质量发展的重要途径和关键点.本研究基于成渝地区双城经济圈36个市（区、县）面板数据,构建了人口-经济-环境系统协调发展指标体系,利用综合指标评价法、耦合模型、耦合协调模型等测算了2010—2019年成渝地区双城经济圈人口-经济-环境复合系统综合发展水平、耦合度及耦合协调度,据此分析研究时段内三元系统耦合协调的时空演变特征及规律,并对子系统发展差异性进行初探.结果表明：整体上,成渝地区双城经济圈耦合协调度和经济、环境子系统发展水平呈不断升高趋势;时序上各市（区、县）人口-经济-环境耦合协调发展关系呈良性向上发展趋势;空间上呈现“两核突出、中部塌陷,外围高于内部”的分布格局和“外围包围中部、由西向东推进”演变特征;研究时段内成渝地区双城经济圈各市（区、县）子系统滞后问题得到极大改善,呈“无序-有序、同步滞后-局部滞后”发展演变趋势和“U”型发展空间格局,但发展过程中人口子系统依旧存在较严重滞后问题.     

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.     

山地城镇化与资源环境承载力耦合协调发展的时空演变

中国是山地大国,在生态文明建设理念下,如何实现山地城镇化与资源环境承载力的协调发展,已经成为我国亟待解决的重大难题. 基于我国西南地区三省一市(重庆市、四川省、云南省、贵州省)的31个地级市2004—2018年面板数据,运用综合评价法和耦合协调度模型,揭示了山地城镇化与资源环境承载力耦合协调的时空演变特征. 结果表明:①西南地区综合城镇化指数和资源环境承载力均呈稳步增长趋势,二者差距逐渐缩小,但由于发展水平较低,仍处于低度耦合协调阶段. ②在空间格局上,都市圈内城市属于高承载、高发展、中度耦合协调度地区,但重庆市、昆明市以及一些工业型城市由于人口和财富在城市高度集聚,其资源环境承载力显著低于西南地区平均值;以高山大川为界的省际交界地区,由于自然地理上的“分割”,城镇化发育不足,属于高承载、低发展、低度耦合协调度地区. 研究显示,山地城镇化与资源环境承载力之间的耦合关系日趋紧密,应推进以人为本的绿色城镇化道路,使两大系统处于良好的耦合协调状态.      

Effects of two sludge application on fractionation and phytotoxicity of zinc and copper in the soil

The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic bound (OM) became predominance of Zn and organic bound Cu occupied the largest portion. There was more available amount of Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to ΔEXCH and ΔCAR forms but also in ΔOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by ΔEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.     

Intraspecific differences in effects of co-contamination of cadmium and

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium (Cd)(0-10 mg/L) and arsenate (As(V)) (0-8 mg/L) on the growth parameters and accumulation of Cd and As in six wheat varieties Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongmai-8. The endpoints of wheat seedlings, including seed germination,biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties (p ＜ 0.05). The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11,Jing-411, Jingdong-8 and Zhongmai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongmai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.     

Toxic effects of acetochlor, methamidophos and their combination on nifH gene in soil

Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis （DGGE） and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity （both in gene richness and diversity index values） and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor （50 mg/kg） recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos （150 mg/kg） caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos （250 mg/kg） produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes （bands） responded differently to the impact of agrochemicals： four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.     

Arsenic uptake by arbuscular mycorrhizal maize （Zea mays L.） grown in an arsenic-contaminated soil with added phosphorus

The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.     

Degradation of metabolites accumulated of benzo[a]pyrene by coupling Penicillium Chrysogenum with KMnO4

Several main metabolites of benzo[a]pyrene （BaP） formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone （BP 1,6- quinone）, trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene （BP 7,8-diol）, 3-hydroxybenzo[a]pyrene （3-OHBP）, were identified by high-performance liquid chromatography （HPLC）. The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that （1） the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; （2） the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; （3） the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% （w/v）, concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.     

Impact of atrazine and nitrogen fertilizers on the sorption of chlorotoluron in soil and model sorbents

Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.     

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.