Relationship between herbaceous community distribution and soil environmental factors in the riparian zone of the Baiyangdian River Basin北大核心CSCD

Riparian zone vegetation is an important part of the riparian ecosystem and plays an important role in the riparian zone functioning. Herbs, which are one of the main types of riparian vegetation, are extremely sensitive to environmental changes and human activities and have become a hot spot of riparian vegetation research. In this study, the herbaceous communities of four representative rivers (Xiaoyi, Baohe, Fuhe, and Baigouyin River) entering Baiyangdian Lake in China were researched. The herbaceous species in their riparian zones were systematically investigated using the sample plot method. The Shannon-Wiener diversity (H’), Pielou evenness (J), and Patrick richness (R) indices were estimated to examine the species composition and diversity of the herb communities, following which redundancy analysis (RDA) was conducted. The relationship between species diversity, distribution patterns of herbaceous plant communities, and soil environmental factors in the riparian zone of the four rivers is discussed. (1) Eighty-three species of herbaceous plants belonging to 66 genera and 27 families in the riparian zone entering Baiyangdian Lake. Most herbaceous plants, including Poaceae, Compositae, and Chenopodiaceae, were weeds or associated plants. Riparian vegetation was greatly affected by human disturbance. (2) All the three estimated indices of the Xiaoyi, Baigouyin, and Fuhe rivers were better than those of the Baohe River. (3) The vegetation coverage and species diversity of riparian herbaceous communities were positively correlated with soil organic matter and water content but negatively correlated with pH, total nitrogen, and total phosphorus. Therefore, these communities are conducive to the restoration of vegetation and the stability of biodiversity in the riparian core area to reduce the disturbance of human activities and increase humidity. © 2022 Science Press. All rights reserved.     

Fate of microplastics in a coastal wastewater treatment plant: Microfibers could partially break through the integrated membrane system

• Fate of microplastics in integrated membrane system for water reuse was investigated. • Integrated membrane system has high removal efficiency (>98%) for microplastics. • Microplastics (>93%) were mainly removed through membrane bioreactor treatment. • Small scale fiber plastics (<200 μm) could break through reverse osmosis (RO) system. • The flux of microplastics maintained at 2.7 × 10¹¹ MPs/d after the RO treatment. Rare information on the fate of microplastics in the integrated membrane system (IMS) system in full-scale wastewater treatment plant was available. The fate of microplastics in IMS in a coastal reclaimed water plant was investigated. The removal rate of microplastics in the IMS system reached 93.2% after membrane bioreactor (MBR) treatment while that further increased to 98.0% after the reverse osmosis (RO) membrane process. The flux of microplastics in MBR effluent was reduced from 1.5 × 10¹³ MPs/d to 10.2 × 10¹¹ MPs/d while that of the RO treatment decreased to 2.7 × 10¹¹ MPs/d. Small scale fiber plastics (<200 μm) could break through RO system according to the size distribution analysis. The application of the IMS system in the reclaimed water plant could prevent most of the microplastics from being discharged in the coastal water. These findings suggested that the IMS system was more efficient than conventional activated sludge system (CAS) for the removal of microplastics, while the discharge of small scale fiber plastics through the IMS system should also not be neglected because small scale fiber plastics (<200 μm) could break through IMS system equipped with the RO system.     

竹林河岸带土壤反硝化脱氮效果模拟及机理研究

以太湖流域上游南苕溪流域农业区竹林河岸带土壤为研究对象,采用乙炔抑制法研究不同外源硝态氮（NO₃^--N）添加量(模拟添加NO₃^--N浓度分别为0、5和10 mg·L^-1的污水,分别用N0、N5和N10处理表示)对不同离水距离（0～3、3～6、6～12 m）、不同深度（0～10、10～20、20～40 cm）土壤反硝化速率的影响.结果表明,N0、N5和N10处理的土壤72 h内的反硝化速率均值分别为59.65、163.56和295.81μg·kg^-1·h^-1,不同处理间差异显著.N5和N10处理的土壤对外源NO₃^--N的脱氮率均值分别为0.45和0.51,且N5处理显著低于N10处理;土壤反硝化速率和对外源NO₃^--N脱氮率均随NO₃^--N添加量的增大而增加.土壤反硝化速率随离水距离的增加而降低,表层土壤的...     

确定卫生防护距离应注意的问题

本文总结了石化行业卫生防护距离标准编制和环境影响评价工作中的经验，对确定卫生防护距离时应注意的一些问题进行了探讨，并提出了一种新的确定石化装置废气无组织排放量的方法。     

涝洼农区畜牧业生产现状与发展对策—以监利县为例

分析了监测县涝洼农区发展节粮型畜牧业的有利条件和存在的问题，提出了充分利用本地自然资源，发展节粮型畜牧业的对策。     

屠宰厂项目环境防护距离的确定

综合考虑外界潜在污染源对屠宰厂的环境影响,从大气环境防护距离、卫生防护距离及外界潜在污染源的环境影响评价出发,分析污染评价因子的选取、标准值的确定、预测模式的选取和预测结果评价,实例探讨了屠宰厂项目环境防护距离的确定方法。结果表明,拟建化工项目未对屠宰厂的环境空气质量造成影响,TSP是外界污染源对屠宰厂影响最大的污染因子,综合计算大气环境防护距离值和卫生防护距离值得到屠宰厂的环境防护距离为300m。     

北京房山山区沟域经济产业空间布局研究

沟域经济是山区发展研究的新视角,通过对房山山区自然地理格局、 综合生态系统敏感性及服务功能分析,得出深山区-两大流域区-浅山区的生态功能区划格局。在生态功能区划的基础上,对相对综合资源承载力作出评价,确保从地域整体视角统筹区域发展,将开发强度控制在资源环境承载力范围之内。结果表明,根据不同功能区生态承载力的空间和阈值差异,可将沟域产业空间布局划分为深山限制发展区、 大石河重点发展区、 拒马河重点发展区和浅山优先发展区4类产业调控区,通过分析不同类型区的特征,分别制订产业准入门槛、 产业规模和产业发展方向等产业发展调控策略。     

成渝经济区火电发展的大气环境影响

基于CALPUFF模型,以2007年为基准年,根据成渝经济区基准年火电SO₂排放量、2008—2009年国家核定的火电SO₂减排量(20.9×104 t)、“十二五”年地方计划火电SO₂减排量(18.5×104 t)以及地方愿景下的“十二五”期间新增火电SO₂排放量,设计3种不同排放情景,并且对不同情景下的ρ(SO₂)分布特征进行了模拟. 结果表明:2008年和2009年成渝经济区的火电SO₂减排使成渝经济区的ρ(SO₂)年均值比2007年平均降低了18.9%;“十二五”新增火电装机将会使成渝经济区的ρ(SO₂)年均值比2007年平均升高20.7%. 虽然通过工程减排及“上大压小”的方式减缓了新增火电机组带来的影响,但从空间分布来看,ρ(SO₂)增加的局部地区与酸雨严重的地区高度重合,导致该区域酸雨污染风险依然存在.      

近岸海域环境功能区概念辨析及其存在的问题和对策

近岸海域环境功能区是进行近岸海域水环境管理的重要依据.随着经济和环境保护形势的发展,我国近岸海域环境功能区管理也应进行相应的调整.研究了近岸海域环境功能区与海洋功能区之间的差别,根据近岸海域环境功能区的定位,指出其应主要包含3个属性,即自然属性、社会属性和管理属性,因此近岸海域环境功能区划分应立足于保护当地的海洋生态系统,满足人类对近岸海域水体的使用功能,同时方便对近岸海域环境系统的管理.对近岸海域环境功能区目前存在的主要问题进行了分析,即超标严重、调整频繁、排污混合区设置不合理以及监管有待加强等.在此基础上,提出应突出近岸海域环境功能区战略定位,将近岸海域环境功能区划上升为国家标准,加强近岸海域环境功能区的生态保护功能,加快修编《近岸海域环境功能区划分技术规范》,并强化环境保护部对近岸海域环境功能区的监督管理等对策建议.      

大都市传统工业区休闲旅游转型发展研究综述

传统工业区休闲旅游转型是大都市城市功能和产业空间优化的关键问题,目前该方面研究尚未形成系统性的理论研究体系.论文梳理了国内外相关研究成果,从休闲旅游转型趋势,转型价值,转型空间演化,转型要素,转型模式,转型效应和转型策略等方面进行了研究内容和研究结果的总结,评述了国内外在研究时间,研究内容,研究方法上的差异.最后认为现有研究缺乏从人地关系视角对传统工业区转型背景,要素,动力,空间演化的系统分析,今后应针对中国大都市发展特点,重点关注传统工业区休闲旅游转型发展模式,转型过程,机制以及综合效应等方面的研究,从理论性和可操作性上指导我国城市传统工业区的休闲旅游改造.