Assessment on the effectiveness of environmental regulation in China—evidence from a panel data analysis

Environmental Science and Pollution Research - In the context of global warming and environmental deterioration, the environment impact assessment is a crucial institutional guaranty to assure less...     

The key elements analysis of Guangdong & Shenzhen ETS & tips for China national ETS construction

The only joint effort area of provincial and municipal governments resides in Guangdong Province and Shenzhen City in China’s carbon emission trading system (ETS) pilots, which characterize the national carbon ETS plots. The present study on the operating experience from this area has important reference value for the national carbon ETS. Analysis and comparison of the key elements show many differences in coverage, total allowance, allowance allocation, and MRV mechanism between Guangdong and Shenzhen carbon ETS. The present study provides the following explanation: (1) the design characteristics of carbon ETS (e.g. coverage, total quotas, the allocation, and MRV mechanism) depend on the local geographical conditions and policy goals. The differences of economic structure in Guangdong Province and Shenzhen City result in different coverage, which then result in differences in other management elements. (2) The operating state of the carbon market is affected by overall design of carbon ETS: in the case of tighter total allowance, lower proportion of China Certified Emission Reductions, and harsher punishment, the carbon market is relatively active, which intends to produce carbon financial market. Based on deep analysis of operation characteristics of carbon ETS in Guangdong and Shenzhen, the present study suggests that (1) the allowance should be allocated freely at the beginning stage and then gradually transited to the voluntary paid auction; (2) the allowances assigned to companies shall be linked up with their energy-saving objectives; (3) the output fluctuations and economic influence on the allowance allocation should be properly handled to maintain the fairness and consistence of allowance allocation standards; (4) stable public expectation is one of the key elements to maintain the regular operation of carbon ETS; (5) constrained carbon emission behavior outside ETS can contribute to social justice; and (6) the improvement of professional skills of relevant personnel in the enterprise and independent third party can enhance carbon emissions data reliability.     

中国水产养殖规划现状分析与对策

水产养殖规划可以降低水产养殖和水环境之间的不确定性、减少水产养殖活动的外部不经济性、提高水资源的利用效率,对中国水产养殖的可持续发展有重要作用.对已实施的水产养殖规划的现状分析结果表明,存在着水产养殖规划基础与水产养殖规划实施间的不协凋性、环境影响评价环节的缺失和水产养殖规划的实施效果蔗等主要现象.其根本原因是现有水产养殖相关制度的配置不完善.应从环境影响评价与水产养殖规划的集成关系入手,通过完善水产养殖容量的估算、水产养殖的技术与经济评估指标、制度和相关利益者分析与评估的方法和指标,建立水产养殖规划的技术体系.引入第三方评审制度以监督规划环境影响评价的质量.     

新型转式垃圾焚烧过程中脱氯脱硫机理的研究

为了探讨有机垃圾焚烧过程钙基添加剂对HCl,SO_x生成特性的影响,分别在自行设计的中空水冷转式垃圾焚烧炉和固定床加热炉中进行了一系列的实验,研究结果表明新型转式焚烧炉具有强化传热传质特性,能提高HCl、SO_x的脱除率,可抑制有害气体的生成;同时也研究了 HCl,SO₂气体同时存在时,钙基添加剂对脱氯脱硫效率的影响规律。     

Nitrogen fertility and abiotic stresses management in cotton crop: a review

This review outlines nitrogen (N) responses in crop production and potential management decisions to ameliorate abiotic stresses for better crop production. N is a primary constituent of the nucleotides and proteins that are essential for life. Production and application of N fertilizers consume huge amounts of energy, and excess is detrimental to the environment. Therefore, increasing plant N use efficiency (NUE) is important for the development of sustainable agriculture. NUE has a key role in crop yield and can be enhanced by controlling loss of fertilizers by application of humic acid and natural polymers (hydrogels), having high water-holding capacity which can improve plant performance under field conditions. Abiotic stresses such as waterlogging, drought, heat, and salinity are the major limitations for successful crop production. Therefore, integrated management approaches such as addition of aminoethoxyvinylglycine (AVG), the film antitranspirant (di-1-p-menthene and pinolene) nutrients, hydrogels, and phytohormones may provide novel approaches to improve plant tolerance against abiotic stress-induced damage. Moreover, for plant breeders and molecular biologists, it is a challenge to develop cotton cultivars that can tolerate plant abiotic stresses while having high potential NUE for the future.     

文思湖底泥COD释放规律模拟研究

采用室内模拟实验方法,研究环境因子（温度、pH、扰动强度、供气量）对底泥释放COD的影响。结果表明,水温升高能加速底泥中有机质的释放;上覆水在弱酸至中性条件下底泥释放有机质最低;扰动上覆水体会加快有机质的释放。     

Synthesis of hybrid carbon nanotubes using Brassica juncea L. application to photodegradation of bisphenol A

Hyperaccumulators contain tubular cellulose and heavy metals, which can be used as the sources of carbon and metals to synthesize nanomaterials. In this paper, carbon nanotubes (CNTs), Cu_0.05Zn_0.95O nanoparticles, and CNTs/Cu_0.05Zn_0.95O nanocomposites were synthesized using Brassica juncea L. plants, and the ultraviolet (UV)-light-driven photocatalytic degradations of bisphenol A (BPA) using them as photocatalysts were studied. It was found that the outer diameter of CNTs was around 50 nm and there were a few defects in the crystal lattice. The synthesized Cu_0.05Zn_0.95O nanocomposites had a diameter of around 40 nm. Cu_0.05Zn_0.95O nanocomposites have grown on the surface of the CNTs and the outer diameter of them was around 100 nm. The synthesized hybrid carbon nanotubes using B. juncea could enhance the efficiency of photocatalytic degradation on BPA. The complete equilibration time of adsorption/desorption of BPA onto the surface of CNTs, Cu_0.05Zn_0.95O nanoparticles, and CNTs/Cu_0.05Zn_0.95O nanocomposites was within 30, 20, and 30 min, and approximately 14.9, 8.7, and 17.4 % BPA was adsorbed by them, respectively. The combination of UV light irradiation (90 min) with CNTs, Cu_0.05Zn_0.95O nanoparticles, and CNTs/Cu_0.05Zn_0.95O nanocomposites could lead to 48.3, 75.7, and 92.6 % decomposition yields of BPA, respectively. These findings constitute a new insight for synthesizing nanocatalyst by reusing hyperaccumulators.     

赤铁矿的硫化改性及硫化产物对水中六价铬的还原固定化

以赤铁矿为原料、硫化钠为硫化试剂,对赤铁矿进行了硫化改性,考察了硫化赤铁矿(SH) 对水中六价铬Cr(Ⅵ) 的还原固定化性能。 Langmuir等温吸附模型拟合结果表明,该材料在pH=7时对Cr(Ⅵ)的最大吸附量为66.7 mg·g⁻¹,约为原始赤铁矿的39倍。SH对 Cr(Ⅵ) 的去除过程符合准二级动力学模型,表明该过程可能受化学吸附控制。进一步采用TEM、XRD等手段对SH进行了表征,并结合材料吸附前后的XPS图谱变化,对SH去除水中 Cr(Ⅵ) 的机制进行了分析。结果表明, 与未改性的赤铁矿相比,硫化改性赤铁矿对Cr(Ⅵ)去除性能显著提高的原因可能源于赤铁矿表面形成的铁-硫化合物层。在SH还原固定化 Cr(Ⅵ) 的过程中,表面硫化层中的还原性物质FeS、吸附态 Fe(Ⅱ) 和 S(-II) 将 Cr(Ⅵ) 还原为 Cr(Ⅲ),从而实现对Cr(Ⅵ) 的稳定化。     

Rapid degradation of butachlor in wheat rhizosphere soil

The degradative characteristics of butachlor in non-rhizosphere, wheat rhizosphere, and inoculated rhizosphere soils were measured. The rate constants for the degradation of butachlor in non-rhizosphere, rhizosphere, and inoculated rhizosphere soils were measured to be 0.0385, 0.0902, 0.1091 at 1 mg/kg, 0.0348, 0.0629, 0.2355 at 10 mg/kg, and 0.0299, 0.0386, 0.0642 at 100 mg/kg, respectively. The corresponding half-lives for butachlor in the soils were calculated to be 18.0, 7.7, 6.3 days at 1 mg/kg, 19.9, 11.0, 2.9 days at 10 mg/kg, and 23.2, 18.0, 10.8 days at 100 mg/kg, respectively. The experimental results show that the degradation of butachlor can be enhanced greatly in wheat rhizosphere, and especially in the rhizosphere inoculated with the bacterial community designated HD which is capable of degrading butachlor. It could be concluded that rhizosphere soil inoculated with microorganisms-degrading target herbicides is a useful pathway to achieve rapid degradation of the herbicides in soil.     

Effects of EDTA and low molecular weight organic acids on soil solution properties of a heavy metal polluted soil

A pot experiment was conducted to study the effects of EDTA and low molecular weight organic acids (LMWOA) on the pH, total organic carbon (TOC) and heavy metals in the soil solution in the rhizosphere of Brassica juncea grown in a paddy soil contaminated with Cu, Zn, Pb and Cd. The results show that EDTA and LMWOA have no effect on the soil solution pH. EDTA addition significantly increased the TOC concentrations in the soil solution. The TOC concentrations in treatments with EDTA were significantly higher than those in treatments with LMWOA. Adding 3 mmol kg(-1) EDTA to the soil markedly increased the total concentrations of Cu, Zn, Pb and Cd in the soil solution. Compared to EDTA, LMWOA had a very small effect on the metal concentrations. Total concentrations in the soil solution followed the sequence: EDTA > citric acid (CA) approximately oxalic acid (OA) approximately malic acid (MA) for Cu and Pb; EDTA > MA > CA approximately OA for Zn; and EDTA > MA > CA > OA for Cd. The labile concentrations of Cu, Zn, Pb and Cd showed similar trends to the total concentrations.