中国化石能源消费碳排放与经济增长关系研究

化石能源过度消费导致的气候变化问题引发了全世界对经济发展模式的关注,论文运用计量经济学方法研究了中国化石能源消费碳排放与经济增长的关系,测算了中国1953-2010年化石能源消费引起的碳排放总量,建立了碳排放总量和国内生产总值的时序计量经济模型,通过协整检验、误差修正模型、基于VAR模型的脉冲响应函数、因果关系检验,分析了二者之间的长短期关系,结果表明:1953-2010年,我国的化石能源消费碳排放总量和国内生产总值之间存在长期均衡的协整关系和短期动态调整机制,通过短期调节,可以自动实现二者之间的长期均衡。当期GDP对碳排放总量的当期波动有显著性影响,每增加1%的GDP便会增加0.719%的碳排放量,上期误差对碳排放总量的当期波动调整幅度较大,单位调整比例为-0.102。利用脉冲响应函数波形图对碳排放量与经济增长之间的影响及响应进行了20期的详细刻画,揭示了二者之间复杂的短期动态关系。1953-2010年,存在从碳排放总量到GDP的单向Granger因果关系,碳排放是经济增长的Granger原因,而经济增长不是碳排放的Granger原因,说明从过去58 a的整体状况来看,高碳排放推动了经济增长,而经济增长并未导致明显的碳排放增加。研究结果将对中国制定节能减排和碳减排政策提供依据和支撑。     

基于能源消费的浙江省碳排放影响因素实证研究

本文运用协整和Granger因果检验方法,实证了在1995-2013年间浙江省碳排放与经济增长、能源效率、对外贸易、城市化和人口增长的现实关系。研究表明:浙江省碳排放与经济增长之间呈现"弱脱钩"关系,对外贸易、经济增长和人口增长对碳排放有正向驱动效应,而能源效率和城市化水平对碳排放有负向驱动效应。Granger因果关系上,对外贸易、经济增长、城市化水平和人口增长是引起浙江省碳排放变化的Granger原因,且仅存在单向影响机制,能源效率与碳排放互为Granger因果关系。     

农业碳排放与经济增长实证研究

本文选取甘肃省2001-2011年的数据,通过相应的计量分析方法,研究了农业碳排放和经济增长之间的关系。研究表明甘肃省农业碳排放量和强度逐年增长,但增长速度处于阶段性下降状态,同时经济增长和化肥、农药等农业碳源导致的碳排放强度之间存在一定的协整关系,并对此给出了降低农业碳排放量的建议。     

能源消费、能源效率与中国经济增长的协整分析研究

利用协整理论和基于误差修正模型的Granger因果关系检验分析了中国能源消费、能源效率和经济增长的关系。协整检验表明这三者之间存在长期协整关系,GDP和能源消费之间存在双向因果关系,而GDP和能源效率之间不存在因果关系。进一步脉冲响应函数分析结果表明,能源消费和GDP在长期内存在较强的双向正向效应;中国GDP在长期内对能源效率将会产生较强的正向效应,而能源效率则对GDP存在微弱的负向效应。     

森林碳汇与经济增长的长期均衡及短期动态关系研究——基于中国1998—2010年省级面板数据

森林是重要的陆地生态系统,森林碳汇与经济增长的长期均衡及短期动态关系的研究,有利于探求森林生态系统平衡发展及经济可持续增长的有效路径。测度中国30 个省份1998—2010 年的森林碳汇,采取面板数据的单位根检验、协整检验、误差修正模型的因果关系检验、脉冲响应等计量技术,考察并预测森林碳汇与经济增长间的动态关系。实证结果表明:森林碳汇与经济增长之间存在协整关系,并存在短期修正效应,当经济可持续增长偏离长期均衡时,将以19%的力度调整至均衡状态,且Granger 因果关系检验及VAR面板模型结果验证了森林碳汇与经济增长的正的双向互动关系;脉冲响应函数显示,经济增长对森林碳汇发展的稳健性产生微弱的正向冲击,而森林碳汇发展在短期对经济增长的稳定性产生显著的正向生态冲击。据此,提出了加大财政对碳汇森林的政策扶持、树种与造林模式相结合、建立并完善碳汇计量与监测机制、完善投融资渠道、加强森林管理等促进我国森林生态系统持续发展的对策建议。     

浙江省碳排放与经济增长的脱钩关系及驱动因素研究

运用IPCC参考方法、Tapio脱钩模型、协整分析和Granger因果检验,研究了浙江碳排放特征及其驱动因素.结果表明:碳排放量呈增长趋势,碳排放强度呈下降趋势,多数年份碳排放与经济增长之间呈"弱脱钩"状态;经济增长、外贸和人口增长对碳排放正向驱动,能源效率和城市化对碳排放负向驱动;经济增长、外贸、城市化和人口增长是引起碳排放增长的单向Granger原因,能源效率与碳排放互为Granger原因.     

海南省能源消费和碳排放预测研究

以海南省1993—2012年能源消费总量、人口、国民生产总值和工业比重作为研究对象,应用协整理论建立它们之间的关系,并预测不同经济增长情景下2015—2020年海南省能源消费总量和能源消费结构。在此基础上,借助相关方法预测碳排放量,最后根据海南的实际情况提出减排政策建议。     

城镇化、居民生活能源消费与生活碳排放之间关系的实证研究

利用中国1995年－2012年居民生活能源消费数据,通过协整检验、格兰杰因果关系检验等方法对城镇化、居民生活能源消费与碳排放之间关系进行了实证研究,结果发现：城镇化、居民生活能源消费与碳排放存在长期均衡关系;城镇化程度的提高会降低CO2排放;生活能源消费的增加是CO2排放提高的重要原因。居民生活能源消费与CO2排放之间存在着双向格兰杰因果关系。提出稳步推进新型城镇化进程、合理进行生活能源消费、调控城乡居民生活能源消费等建议。     

上海市能耗与GDP大气污染的协整关系研究

采用计量经济学中的协整理论考察上海市能源消费量与经济增长、废气排放量、二氧化硫排放量之间的关系。结果显示,上海市能源消费只与经济增长、废气排放量之间存在长期协整关系,并建立了相应的长期均衡方程及误差修正模型。另外,对1978～2003年的能源消费与经济增长之间进行Granger因果关系检验,提出实现上海市经济-能源-环境和谐发展的措施。     

陕西省经济增长与能源消耗和碳排放关系研究

选取2001年-2011年间统计数据,对陕西省经济发展、能源消耗和碳排放量的情况进行分析,并应用“脱钩”理论对经济增长与能源消耗和碳排放之间关系进行研究.结果表明:2002年-2008年经济增长与能源消耗脱钩指数和经济增长与碳排放脱钩指数均处在扩展脱钩状态,发展状况不太理想;2009年-2011年两个指数均处在弱脱钩状态,状况有所改善,但经济发展质量总体水平不高.提出调整能源产业消费结构、通过技术进步,提高能源利用率及调整产业结构三方面建议.     

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.     

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.     

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.     

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.     

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.     

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.     

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.