应用δ~(13)C值探讨土壤中有机碳的迁移规律

C3 植物与C4 植物具明显的δ13C值差异 ,利用这种特性 ,选取荔波茂兰喀斯特森林边缘处这个C3植物—C4 植物转换生长的地点 ,分别采集森林与农田各三个剖面的土壤样品 ,根据测定其土壤总有机碳、不同粒径及不同比重组分的δ13C值间的相互关系来推导土壤有机碳的若干迁移规律     

原子力显微镜在环境样品研究与表征中的应用与展望

简要阐述了原子力显微镜仪器操作原理及最新成像技术发展情况;结合作者近期的研究工作,从环境微生物界面观察与表征、腐殖酸在微界面上的聚集行为观测、无机高分子絮凝剂的界面形貌及行为观察以及膜材料表面结构观测与表征等4个方面对原子力显微镜在环境领域内的应用情况作了概括介绍．最后,对原子力显微镜在环境微界面研究与表征中的应用前景进行了展望。     

水分管理对水稻生长与根际激发效应的影响特征

作物根际沉积碳输入而引起的根际激发效应,对农田土壤碳排放通量和碳平衡起到关键的调控作用.在稻田生态系统中,由于频繁的干湿交替,土壤CO2 和CH4 排放以及根际激发效应明显有别于其他自然生态系统.因此,明确稻田生态系统干湿交替过程中水稻根际激发效应的方向与强度,对于减缓稻田温室气体排放具有重要意义.本研究采用13C-C...     

Optimum conditions for the formation of Al13 polymer and active chlorine in electrolysis process with Ti/RuO2-TiO2 anodes

A polyaluminum containing a high concentration of Al₁₃ polymer and active chlorine (PACC) was successfully synthesized by a new electrochemical reactor using Ti/RuO₂-TiO₂ anodes. PACC can potentially be used as a dual-function chemical reagent for water treatment. The obtained results indicated that the formation of Al₁₃ polymer and active chlorine, were the most active components in PACC responsible for coagulation and disinfection respectively. These components were significantly influenced by electrolyte temperature, current density, and stirring rate. It was observed that high electrolyte temperature favored the formation of Al₁₃. Increasing current density and stirring rate resulted in high current efficiency of chlorine evolution, thus favoring the generation of Al₁₃ and active chlorine in PACC. When the PACC (Al_T = 0.5 mol/L, basicity = 2.3) was prepared at the optimum conditions by electrolysis process, the Al₁₃ polymer and active chlorine in product reached above 70% of Al_T and 4000 mg/L, respectively. In the pilot scale experiment with raw polyaluminum chloride used as an electrolyte, PACC was successfully prepared and produced a high content of Al₁₃ and active chlorine products. The pilot scale experiment demonstrated a potential industrial approach of PACC preparation.     

经济新常态下的“十三五”环境压力预测

我国经济已经从高速增长转向中高速增长的新常态阶段,经济发展方式从规模速度型粗放增长转向质量效率型集约增长,产业结构从劳动密集型向资金密集型和知识密集型转换,经济发展动力从要素驱动、投资驱动转向创新驱动。经济新常态下,环境保护将迎来难得的历史机遇,同时也面临严峻的挑战。为了深入理解和准确把握经济新常态下我国"环境态"的发展特征,本文基于中长期环境经济预测模型定量测算了2020年我国社会经济、能源和水资源以及主要污染物排放趋势和特征。结果表明,"十三五"期间,我国能源和水资源消耗总量增长将趋缓,新增消耗量进入涨幅收窄期;产业转型升级加速将从源头上减轻新增污染减排的压力,主要大气和水污染物排放将进入高位平台期,排放强度将呈现高位回落。     

“十三五”时期中国环境监管体制改革的形势、目标与若干建议

本文构建了包括监管的立法、组织体系、监管权力配置、监管工具与程序、问责机制、监管能力等要素在内的环境监管体制分析框架,从污染物排放趋势、国家制度建设等角度分析了"十三五"时期中国环境监管体制改革面临的挑战、目标和思路。"十三五"时期是中国生态文明建设的重要时期,完善环境监管制度是推进生态文明制度体系建设的重要内容。面对严重环境污染所带来的挑战,在此期间加快环境监管体制改革、提高环境监管有效性是切实实现治污减排的根本保证。完善环境监管体系、改进监管方式、创新监管手段是建立治污减排长效机制的基础和前提,也是完善环境治理体系的重要内容。按照市场经济条件下政府依法行政的要求,中国环境监管体制改革的目标,就是要按照合法性、独立性、透明性、可问责性、专业性和执法能力、可信性等原则建立和完善现代环境监管体制,为此必须从专门立法、组织结构、权力分配、问责机制、监管程序与工具、监管能力建设等各方面推进改革。本文提出了"十三五"时期环境监管体制改革的思路及若干建议,主要包括:加快修订环保法律法规,提高法律的可操作性,推进环境司法常态化、规范化和专门化,进一步提升环境监管法治化水平;从纵向、横向上优化环境监管组织结构,强化区域层级的监管与督查功能,强化中央层级环境监管机构对环境信息的获取能力;优化环境保护主管部门机构设置以及相关职能,建立并完善内部机构的协调机制;完善环境监管的内外部问责机制,把做实对监管者的监管机制作为优化环境监管体制的抓手;强化对监管工具的顶层设计,做实监管程序中关键环节,建立环境监管影响评估制度;加强环境监管能力建设,推进环境监管制度队伍职业化发展,保障各级环境监管机构具有充分履职的能力。环境监管体制的改革和完善,是国家治理体系和治理能力现代化的重要内容。     

关于国家环境保护“十三五”规划的战略思考

在对我国当前环境形势以及未来重大环境保护问题识别的基础上,结合国家生态文明建设新要求,提出了"十三五"环境保护规划体系以及规划目标的设想,并从国民经济绿色化、国土空间功能化、保护环境法治化、环境供给市场化、决策监管科学化、治理主体多元化、环境信息公开化等7个方面给出了基本策略建议,可为制定国家"十三五"环境保护规划提供参考。     

2,4-dichlorophenoxyacetic acid (2,4-D) micropollutant herbicide removing from water using granular and powdered activated carbons: a comparison applied for water treatment and health safety

Abstract

Activated carbons are well-known porous materials as an effective adsorbent used for the removal of emerging contaminants, such as herbicides, which are increasingly present in water bodies. Most water treatment plants, specially in Brazil, are unable to completely remove such contaminants by the conventional process and advanced treatment using activated carbons is required. The aim of this paper was to verify the influence of the activated carbons granulometry and specific surface area on the 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide removal efficiency using distilled-deionized water and filtered water collected from a conventional Water Treatment Plant. Commercial activated carbons samples used in this work were obtained from two different manufacturers. Activated carbons were analyzed by the specific surface area, pore size and volume distribution, nuclear magnetic resonance, infrared and x-ray spectroscopy, moisture, volatile matter and ash contents. Batch adsorption isotherms experiments were used and performed by Langmuir and Freundlich models. Granular and powdered activated carbons removed over 99% of 2,4-D in distilled water and near to 99% using filtered water. The activated carbons evaluated in this work presented high performance and played a key role in water treatment by removing 2,4-D herbicide, ensuring the protection of human health and the ecosystem.