A study on aquaculture industry regulations and policies of globally representative states

Aquaculture has a long history,and has achieved rapid development from 1950 to 2010,especially since the 1990s.Nevertheless,aquaculture has also seen a series of problems emerge.Inevitably,aquaculture interacts with the environment and society.Rapid development requires that close attention be paid to potential environmental and social impacts and their prevention or mitigation.The development and management of aquaculture is related closely with a variety of legal and institutional arrangements.Thus,aquaculture raises numerous legal and institutional issues.This paper explores actual legal and institutional practices of global representative aquaculture countries and provides a comprehensive account of the legislation and policies of different countries.Further,this paper reveals that the optimal legal framework for aquaculture is in line with related international regulations(especially the soft laws)and strictly operational,and the corresponding policy framework should establish early access and warning,as well as post assessment and feedback mechanisms.     

长江口及其邻近海域表层沉积物中有机污染物复合毒性与多环芳烃毒性贡献

本研究利用发光细菌急性毒性实验测定了长江口及其邻近海域表层沉积物中有机污染物的复合毒性,同时运用气相色谱-质谱联用仪测定了沉积物中16种美国环境保护局(United States Environmental Protection Agency, US EPA)规定的优先控制的多环芳烃(polycyclic aromatic hydrocarbons, PAHs)的浓度。在此基础上,分析其时空分布特征及多环芳烃毒性贡献,并评估其环境风险。结果表明,2019年长江口及邻近海域表层沉积物中16种PAHs总浓度范围为32.84～283.47 ng·g^(-1);2020年浓度范围为66.93～132.64 ng·g(-1);2020年浓度范围为66.93～132.64 ng·g^(-1)。在空间分布上,2019年长江口表层沉积物中PAHs在靠近渔港的区域呈现较高浓度(S3=(283.47±29.94) ng·g(-1)。在空间分布上,2019年长江口表层沉积物中PAHs在靠近渔港的区域呈现较高浓度(S3=(283.47±29.94) ng·g^(-1)),而2020年在靠近舟山岛的区域呈现较高浓度(L6=(132.64±9.95) ng·g(-1)),而2020年在靠近舟山岛的区域呈现较高浓度(L6=(132.64±9.95) ng·g^(-1))。与2019年相比,2020年多环芳烃的平均浓度有所降低,且其细胞毒性量化指标——生物分析当量浓度(BEQ_(bio))的平均值(66.62 mg·kg(-1))。与2019年相比,2020年多环芳烃的平均浓度有所降低,且其细胞毒性量化指标——生物分析当量浓度(BEQ_(bio))的平均值(66.62 mg·kg^(-1))远低于2019年(128.20 mg·kg(-1))远低于2019年(128.20 mg·kg^(-1))。在长江口沉积物毒性当量浓度中PAHs所占比例较小,2019年和2020年由PAHs引起的细胞毒性的平均占比分别为4.46%和4.25%。该结果表明,检测到的PAHs仅能解释所观察到的复合毒性效应的一小部分,因此,还需要进一步对其他未检测的化学物质进行测试分析。     

Degradation of sulfadiazine by UV/Oxone: roles of reactive oxidative species and the formation of disinfection byproducts

Environmental Science and Pollution Research - Sulfadiazine (SDZ) is a typical persistent sulfonamide antibiotic, which has been widely detected in natural drinking water sources. The degradation...     

Effects of Environmental Aging on the Durability of Wood-Flour Filled Recycled PET/PA6 Wood Plastic Composites

Journal of Polymers and the Environment - Outdoor building materials made of wood require preservatives containing chromated copper arsenate and other carcinogenic substances but still are subject...     

基于彼得斯治理理论的京津冀协同发展路径重构

基于彼得斯治理理论,分析了京津冀地区的协同发展现状和要求,重构了其协同发展路径。结果表明:①要素禀赋、区域政策分别是区域协同发展的客观基础和主观条件。②区域协调发展新机制为京津冀地区提出了“坚持以北京和天津尤其是以非首都功能疏解为引领,借助市场力量调动各个主体的积极性,同时注重协同方式(机制)建设”的新要求。③京津冀协同发展路径重构可从“由软硬兼施的市场(市场平台和政府效能)、三维协同的主体(地方政府,中央政府和非政府部门)和富有弹性的方式(临时机构和互动机制)”的“3M”策略入手。     

A Hydrologic Data Screening Procedure for Exploring Monotonic Trends and Shifts in Rainfall and Runoff Patterns

A thorough understanding of past and present hydrologic responses to changes in precipitation patterns is crucial for predicting future conditions. The main objectives of this study were to determine temporal changes in rainfall‐runoff relationship and to identify significant trends and abrupt shifts in rainfall and runoff time series. Ninety‐year rainfall and runoff time series datasets from the Gasconade and Meramec watersheds in east‐central Missouri were used to develop data screening procedure to assess changes in the rainfall and runoff temporal patterns. A statistically significant change in mean and variance was detected in 1980 in the rainfall and runoff time series within both watersheds. In addition, both the rainfall and runoff time series indicated the presence of nonstationary attributes such as statistically significant monotonic trends and/or change in mean and variance, which should be taken into consideration when using the time series to predict future scenarios. The annual peak runoff and the annual low flow in the Meramec watershed showed significant temporal changes compared to that in the Gasconade watershed. Water loss in both watersheds was found to be significantly increasing which is potentially due to the increase in groundwater pumping for water supply purposes.     

Algal purification of pretreated landfill Leachate

The efficiency of microalgae in removing various pollutants in landfill leachate after pretreatment by free stripping or air stripping was tested by a laboratory batch system. The results showed that Chlorella pyrenoidosa and Scenedesmus sp. had similar removal efficiencies with regard to ammoniacal‐nitrogen, oxidized‐nitrogen, orthophosphate and chemical oxygen demand (COD). The COD removal by algal treatment was better in Junk Bay (JB) leachate than in Gin Drinkers’ Bay (GDB) leachate (14–21% and 0.4–7% respectively). No significant difference (P > 0.05) was found in removing other nutrients including ammoniacal‐nitrogen, oxidized‐nitrogen and orthophosphate between leachate from the two landfills, regardless of the pretreatment used. The removal efficiencies of ammoniacal‐nitrogen and phosphorus were found to be higher in air‐stripped leachate than in free‐stripped one. Removal of ammoniacal‐nitrogen and phosphorus in air‐stripped leachate was 30% and 87% respectively. Poor removal of ammoniacal‐nitrogen was probably due to a deficiency in phosphorus (high N : P ratio) for algal growth in leachate. The two‐stage leachate treatment (ammonia stripping followed by algal purification) resulted in overall reduction of COD (38–51%), ammoniacal‐nitrogen (72–96%) and orthophosphate (79–96%).     

Exploring price effects on the residential water conservation technology diffusion process: a case study of Tianjin city

Reforms of the water pricing management system and the establishment of a flexible water pricing system are significant for cities in northern China to tackle their critical water issues. The WATAP (Water conservation Technology Adoption Processes) model is developed in order to capture the water conservation technology adoption process under different price scenarios with disaggregate water demands down to the end use level. This model is explicitly characterized by the technological selection process under maximum marginal benefit assumption by different categories of households. In particular, when households need to purchase water devices in the provision market with the consideration of complex factors such as the life span, investment and operating costs of the device, as well as the regulated water price by the government. Applied to Tianjin city, four scenarios of water price evolutions for a long-term perspective (from year 2011 to 2030) are considered, including BAU (Business As Usual), SP1 (Scenario of Price increase with constant annual rate), SP2 (Scenario of Price increase every four years) and SP3 (Scenario of Price increase with affordable constraint), considering many factors such as historic trends, affordability and incentives for conservation. Results show that on aggregate 2.3%, 11.0% and 18.2% of fresh water can be saved in the residential sector in scenario SP1, SP2 and SP3, respectively, compared with the BAU scenario in the year 2030. The water price signals can change the market shares of different water appliances, as well as the water end use structure of households, and ultimately improve water use efficiency. TheWATAP model may potentially be a helpful tool to provide insights for policy makers on water conservation technology policy analysis and assessment.     

Removal of phenol by powdered activated carbon adsorption

In this study, the adsorption performance of powdered activated carbon (PAC) on phenol was investigated in aqueous solutions. Batch adsorption studies were performed to evaluate the effects of various experimental parameters like PAC type, PAC dose, initial solution pH, temperature and pre-oxidation on the adsorption of phenol by PAC and establish the adsorption kinetics, thermodynamics and isothermal models. The results indicated that PAC adsorption is an effective method to remove phenol from water, and the effects of all the five factors on adsorption of phenol were significant. The adsorption rate of phenol by PAC was rapid, and more than 80% phenol could be absorbed by PAC within the initial 10 min. The adsorption process can be well described by pseudo-second-order adsorption kinetic model with rate constant amounted to 0.0313, 0.0305 and 0.0241 mg·μg ^-1·min ^-1 with coal, coconut shell and bamboo charcoal. The equilibrium data of phenol absorbed onto PAC were analyzed by Langmuir, Freundlich and Tempkin adsorption isotherms and Freundlich adsorption isotherm model gave the best correlation with the experimental data. Thermodynamic parameters such as the standard Gibbs free energy (?G^o), enthalpy (?H^o) and entropy (?S^o) obtained in this study indicated that the adsorption of phenol by PAC is spontaneous, exothermic and entropy decreasing.