Historical changes in the environment of the Chinese Loess Plateau

Historical records from the past 2000 years indicate that the vegetative cover of the Loess Plateau has declined significantly with time. The decline in vegetative cover seems closely related to increased rates of soil erosion as well as the increased frequency of natural disasters such as floods, droughts and dust storms. The condition of the environment and its relationship with development is a serious problem as the Chinese government searches for ways to improve the living standard of people in the region. The purpose of this study is to outline historical changes in the vegetation and environmental conditions of the Loess Plateau. Although we believe that current population pressure of the Loess Plateau is becoming unsustainable, our objective is not to be overly pessimistic in regards to the future development of the region. Instead, our purpose is to increase the awareness of environmental conditions in the region and to encourage the implementation of policies that will promote sustainable development of the Loess Plateau.     

Current status,existent problems,and coping strategy of urban drainage pipeline network in China

Environmental Science and Pollution Research - Urban drainage pipeline systems collect and transport domestic sewage, industrial wastewater, and rainwater. They are important components of urban...     

聚合硫酸铁絮凝剂的物化性质研究

本文通过对直接氧化法聚合硫酸铁(PFS)的热力学研究,首次报道了PFS的一些物化数据:热容、积分溶解热和反应热效应,并根据稀溶液的依数性原理测定了PFS的平均分子量。     

二污染极其在垃圾焚烧中的控制

介绍二的毒性及其在环境中的存在状态,并就在垃圾焚烧中如何控制二的产生及焚烧后残渣、飞灰的处理进行了探讨.     

论社会可持续发展的协调运行机制

社会可持续发展目标的实现必须建立在社会系统协调运行的基础上。社会系统是由人口、资源、环境诸要素组合的社会结构的复合系统。社会可持续发展就是通过社会要素的静态结构、动态结构和区位结构的协调运行表现出来的。     

WASP模型湖库水环境模拟国内外研究进展综述

WASP（The water quality analysis simulation program）模型是美国环保局（EPA）推荐使用的水质模型之一,数年来被广泛应用于各类水体的水质模拟、预测和决策制定.本文简述了WASP模型的基本原理,针对湖泊和水库较为相似的水环境特征,阐述了WASP模型在湖库水环境中应用的国内外进展,总结和分析了WASP模型的应用前景和不足之处,为进行湖库水环境模拟研究和模型的选用提供一定的参考依据.     

Investigation of carbonyl compound sources at a rural site in the Yangtze River Delta region of China

Carbonyl compounds are important intermediates in atmospheric photochemistry, but their primary sources are still not understood well. In this work, carbonyls, hydrocarbons,and alkyl nitrates were continuously measured during November 2011 at a rural site in the Yangtze River Delta region of China. Mixing ratios of carbonyls and hydrocarbons showed large fluctuations during the entire measurement. The average level for total measured volatile organic compounds during the pollution episode from 25 th to 27 th November, 2011 was 91.6 ppb, about 7 times the value for the clean period of 7th–8th, November, 2011. To preliminarily identify toluene sources at this site, the emission ratio of toluene to benzene(T/B) during the pollution episode was determined based on photochemical ages derived from the relationship of alkyl nitrates to their parent alkanes. The calculated T/B was5.8 ppb/ppb, significantly higher than the values of 0.2–1.7 ppb/ppb for vehicular exhaust and other combustion sources, indicating the dominant influence of industrial emissions on ambient toluene. The contributions of industrial sources to ambient carbonyls were then calculated using a multiple linear regression fit model that used toluene and alkyl nitrates as respective tracers for industrial emission and secondary production. During the pollution episode, 18.5%, 69.0%, and 52.9% of measured formaldehyde, acetaldehyde, and acetone were considered to be attributable to industrial emissions. The emission ratios relative to toluene for formaldehyde, acetaldehyde, and acetone were determined to be 0.10, 0.20 and0.40 ppb/ppb, respectively. More research on industrial carbonyl emission characteristics is needed to understand carbonyl sources better.     

纳米银材料的生物安全性研究进展

纳米银材料被广泛应用到医疗、化工、生物等许多领域,增加了与人类接触的可能性,因此关注其生物安全性是很有必要的。本文对近年来纳米银的抗菌性和生物安全性研究进行了综述。首先分析了纳米银的皮肤毒性、呼吸系统毒性、消化系统毒性和其他组织毒性,其次分析了体外细胞毒性和细胞内纳米银与生物大分子相互作用,最后对纳米银材料的人群暴露生物安全性及纳米银与银离子毒性关系进行了探讨。本文旨在为纳米银的毒性作用机制研究提供参考,为建立标准的纳米银安全性评价体系提供依据。     

湖泊连通河道蓝藻通量自动监测方法

湖库中蓝藻细胞一旦形成表层颗粒细胞团形式的水华,就会具有较强的漂移扩散能力,并能对水体景观形成明显影响,成为河湖环境管理的重点关注对象.如何快速高效监测蓝藻颗粒的迁移通量,已成为湖库连通河道水质管理的技术难点.为满足蓝藻水华较重湖泊连通河道蓝藻通量实时监控需求,以太湖梅梁湾连通河道—梁溪河为例,于2019年6-8月蓝藻水华季节,监测了景宜桥断面蓝藻空间分布且逐日监测叶绿素a浓度,并结合岸基式水质和蓝藻自动监测系统,构建了人工监测蓝藻通量与自动监测参数之间的换算关系,开发了梁溪河蓝藻通量的高频自动监测方法并分析了影响因素.结果表明,在U型断面的流通河道中,景宜桥断面的蓝藻在空间分布上呈表层高、底层低、滨岸带略高的特征,近岸表层采样的自动监测系统获得的水体叶绿素a浓度比整个河道断面平均值高出30％;通过建立的蓝藻通量监测方法对比,发现自动与人工监测蓝藻通量逐日变化整体上保持一致,且总量与人工相当,比值为1.07,精确反映了整个河道蓝藻通量的变化规律;2种监测方式的差异性分析表明,原位水质和蓝藻自动监测系统对梁溪河蓝藻通量的实时监控有良好的效果,此系统的应用实现了河道蓝藻通量的实时在线监测,为蓝藻水华应急处置管理提供了关键技术支撑.     

Bioretention for removal of nitrogen: processes,operational conditions,and strategies for improvement

Environmental Science and Pollution Research - As one of the low-impact development measures, bioretention plays an important role in reducing the runoff peak flow and minimizing runoff pollutants,...