长春市1998-2008年玉米虚拟水量动态变化研究

长春市玉米种植面积约占全市粮食种植面积的60%。通过对长春市1998-2008年玉米虚拟水量的计算与分析,探讨其时空分异规律,为长春市玉米生产的可持续发展提供科学依据。11年来长春市玉米虚拟水量呈现不断波动趋势,分别在1999年、2004年和2007年出现高峰值,2003年呈现最低值。对比分析1998年、2004年和2008年五县市区玉米虚拟水量的空间分布,1998年五县市区虚拟水量只分为四个等级,没有达到第五等级;2004年农安县达到第五等级,位居首位,榆树市虚拟水量仍然为第三等级,排名第2,德惠市和九台市均由第一等级上升为第二等级,排名第三,市区位于第一等级,排名最末。到2008年,榆树市由第三等级上升到第四等级,九台市由第二等级下降到第一等级,其他各县市区虚拟水量等级没有变化。     

Public Attitudes Towards Policy Instruments for Congestion Mitigation in Shanghai

Congestion causes many externalities for the society, including time delays, excessive fuel consumption, air pollution, noise and safety concerns. In Shanghai, various policy options have been explored, piloted or applied; however, not all of them may be understood and accepted by the public. A survey was conducted to investigate people＇s attitudes towards several policy options. The main findings reveal that Shanghai residents are resistant to certain policies, such as congestion charges, higher parking charges in congested areas and car restrictions. Instead, they favor public transport provisions. The paper suggests that there is a case for promoting public transport and more efficient trips when the car ownership is still low, and for investing in a policy of educating the public on the ＇true＇ costs and causes of congestion before embarking on ,an intensive policy of congestion charges or restrictions.     

The impact of urban land expansion on soil quality in rapidly urbanizing regions in China: Kunshan as a case study

At a stage of rapid economic development and urbanization in China, most cities are faced with serious problems caused by environment deterioration such as pollution, space press, afforestation degradation, and disordering. Kunshan City, one of the most economically vigorous regions in China, has suffered a more prominent conflict between urbanization and environmental safety. In this paper, urban land expansion in Kunshan City in the Yangtze River Delta was measured with reference to the Landsat data recorded in 1982, 1991, 1995, and 2003 and change in land-use pattern in 1981, 1991, 1995, and 2004 as well as that in nutrients in soils of different purposes between the periods were analyzed to study the effect of urban land-use expansion on soil characteristics. To get a better understanding of soil nutrients, heavy metal content, and pollution, on-the-spot investigation, sampling and laboratory analysis were all conducted, and the geo-accumulation factors and revised Nemerow comprehensive index method were adopted for evaluation of the findings. The results show that the content of organic matter, total nitrogen, rapidly available nitrogen, and available phosphorus in the soil (except available potassium) all increased, and the average content of As, Cd, Cr, Cu, Pb, Ni, Hg, Se, and Zn prove to be 8.61, 0.12, 83.53, 32.49, 29.93, 30.45, 0.27, 0.24, and 93.3 mg kg⁻¹, respectively, showing degradation in soil quality.     

金华市耕地土壤重金属来源解析及健康风险空间分异

不合理的人类活动可能会导致重金属元素在耕地土壤中富集,最终威胁到土壤环境质量、农产品安全及人类健康.以金华市耕地土壤重金属为研究对象,采集了209个表层土壤样品,测定了As、Cd、Cr、Cu、Hg、Ni、Pb、Zn的含量,并采用随机森林模型探讨了金华市耕地土壤重金属的来源.同时,结合人体健康风险评估模型、地统计分析和地理探测器对金华市耕地土壤重金属的健康风险及空间分异进行了评估.结果表明：①金华市耕地土壤中Cd、Cu、Hg、Pb和Zn元素的平均含量超过了浙江省土壤背景值,存在一定程度的积累;②随机森林模型分析表明,As、Cr和Ni主要为自然来源,Hg主要为大气沉降源,Pb和Zn主要为交通来源污染,Cu为农业和工业的共同污染;③健康风险结果显示,金华市耕地土壤重金属污染对儿童总的致癌风险已超过安全阈值,高值区主要出现在金华市的中西部和北部区域;④地理探测器结果显示,金华市相关管理部门有必要对耕地土壤的As、Pb、Cd 、Cr和Cu元素实施分区管控,以降低其健康风险水平.     

城市小区分散式污水生态处理

本文针对目前我国城市集中式污水处理方法的弊端,提出将小型人工湿地运用于城市小区的污水处理,实现环境目标与经济效益的结合。     

可持续发展与地球表层的进化

包括非生物、生物和人的地球表层巨系统,是人的生存环境,它是进化发展的。人类社会只有认识并遵守地球表层的进化规律,才能达到可持续发展的目标。     

矿产资源计价理论与方法的研究

本文论述了矿产资源的价值由矿山级差地租和矿山绝对地租构成,指出了矿产资源的特点决定了矿产资源计价不能采取地租“资本”化的形式,而应按年消耗资源的数量计取并提出了矿产资源计价的基本模型。     

Air quality impact of the coal-fired power plants in the northern passageway of the China West-East Power Transmission Project

This paper analyzes the air quality impacts of coal-fired power plants in the northern passageway of the West-East Power Transmission Project in China. A three-layer Lagrangian model called ATMOS, was used to simulate the spatial distribution of incremental sulfur dioxide (SO2) and coarse particulate matter (PM10) concentrations under different emission control scenarios. In the year 2005, the emissions from planned power plants mainly affected the air quality of Shanxi, Shaanxi, the common boundary of Inner Mongolia and Shanxi, and the area around the boundary between Inner Mongolia and Ningxia. In these areas, the annually averaged incremental SO2 and PM10 concentrations exceed 2 and 2.5 microg/m3, respectively. The maximum increases of the annually averaged SO2 and PM10 concentrations are 8.3 and 7.2 microg/m3, respectively, which occur around Hancheng city, near the boundary of the Shaanxi and Shanxi provinces. After integrated control measures are considered, the maximum increases of annually averaged SO2 and PM10 concentrations fall to 4.9 and 4 microg/m3, respectively. In the year 2010, the areas affected by planned power plants are mainly North Shaanxi, North Ningxia, and Northwest Shanxi. The maximum increases of the annually averaged SO2 and PM10, concentrations are, respectively, 6.3 and 5.6 microg/m3, occurring in Northwest Shanxi, which decline to 4.4 and 4.1 microg/m3 after the control measures are implemented. The results showed that the proposed power plants mainly affect the air quality of the region where the power plants are built, with little impact on East China where the electricity will be used. The influences of planned power plants on air quality will be decreased greatly by implementing integrated control measures.     

生物强化方式对生物转盘处理养殖废水效果及生物多样性的影响

畜禽养殖废水污染物浓度高、生物毒性大,导致传统生物处理工艺难以满足达标排放要求.为探究高效的畜禽养殖废水处理工艺,采用生物转盘作为主体工艺,利用异养硝化-好氧反硝化菌（简称"HN-AD菌"）为生物强化菌剂,对比了强化污泥挂膜和菌剂挂膜两种不同生物强化方式下该工艺在启动时间、碳耗、能耗、真实废水处理效果及微生物多样性方面的差异,以确定最佳生物强化方式.结果表明:①模拟废水试验中,菌剂挂膜反应器启动时间（19 d）明显短于强化污泥挂膜（33 d）,参数优化后发现,在相同处理效果下,前者碳耗、能耗较后者分别低48.22%、33.33%.②真实废水处理试验中,菌剂挂膜反应器的COD_Cr、NH₄+-N、TN平均去除率较后者分别高7.11%、26.97%、29.14%.③在微生物多样性方面,菌剂挂膜体系中Comamonas（丛毛单胞菌属）相对丰度是强化污泥挂膜体系的10倍左右,推测Comamonas可能是在异养硝化好氧反硝化过程中发挥关键作用的菌属.④SEM观察发现菌剂挂膜生物转盘盘片上的生物膜更薄,但HN-AD优势菌富集程度更高.研究显示,菌剂挂膜反应器对模拟废水、真实废水的处理效果均优于强化污泥挂膜反应器,且效果更稳定.      

高炉出铁场高温烟尘扩散与捕集特性模拟

高炉出铁场在出铁过程中产生的高温烟尘污染范围广、时间长、阵发性强。高温铁水上方的气流运动为热羽流,受通风气流影响极大,现有除尘罩设计方法无法有效解决高温烟尘的污染问题。针对我国中小型高炉出铁场厂房形式及出铁特点,建立了出铁场厂房内的两相流动模型及高温烟尘扩散与捕集过程的数值模拟方法。模拟发现,高炉前方的气流上升速度先增加后减小,形成了典型的受限空间热羽流。由于出铁口除尘罩与高炉间存在间隙,在抽吸作用下,底部气流在高炉壁面产生向上的高速气流,使除尘罩对高炉间的气流不具有捕集作用。因屋顶通风量较自然通风少2/3,在仅设屋顶通风除尘时,带走的热量减少,使厂房内温度整体偏高。加设出铁口除尘罩后,厂房整体温度明显降低。出铁口除尘罩对颗粒物的整体捕集率可以达到89.66%,但主沟前方颗粒物大量逃逸,捕集率仅为47.71%,铁水沟后方释放的颗粒物距除尘罩较远,捕集率为86.34%,造成的污染范围较大,是目前出铁场作业环境质量不达标的主要原因。