Rapid regional outburst elimination technology in soft coal seam with soft roof and soft floor

In order to solve the problems in outburst elimination of coal seams with outburst potential, methods of field testing, theoretical analysis and numerical simulation are employed in this study. It is found that the horizontal stress concentration surrounding coal unloading boreholes is the primary cause of the coal and gas blowouts in the process of the coal unloading and permeability improvement with high-pressure water jet. The results indicate that low borehole density and inefficient drainage are the main reasons for the occurrence of high outburst indices in the effeteness validation of regional measures to control outbursts. Based on numerical modeling results and onsite parameter testing, reasonable parameters such as borehole density are determined, and hydraulic fracturing is applied to improve coal seam permeability and relieve stress levels so as to eliminate regional outburst potential. The effect is significant in the field application, coal and gas blowout during the coal unloading period with high-pressure water jet is reduced dramatically, and the roadway development rate is increased by 48%. It is demonstrated that the gas drainage combined with the hydraulic fracturing, coal unloading with high-pressure water jet is a practical and effective technique for rapid elimination of coal and gas outburst potential in roadway development.     

长江流域不同区域间环境公平研究

以区域经济发展水平差距悬殊、环境污染差异明显的长江干流穿过的11个省份为研究对象,并将其分成东部、中部和西部3组,采用统计分析方法探讨经济发展、环境污染排放的区域差异特征。构建了环境公平指数,并分别对2000、2004和2008年3组地区的环境公平程度进行测度,通过聚类分析方法和GIS空间分析工具评价了环境公平指数的空间分布和地域差异。结果表明：长江流域东、中、西部的环境公平指数呈现明显的区域差异现象,并且随着时间的推移和经济的发展,环境公平指数的差异增大,这可能与区域产业转移有关。环境公平指数级别为东部最高,中部和西部较低。但随着西部大开发战略和中部崛起战略的实施,中西部的环境公平指数变化明显。初步认为此现象与国家西部大开发战略和中部崛起战略的实施有关。     

An inventory of trace element inputs to agricultural soils in China

It is important to understand the status and extent of soil contamination with trace elements to make sustainable management strategies for agricultural soils. The inputs of trace elements to agricultural soils via atmospheric deposition, livestock manures, fertilizers and agrochemicals, sewage irrigation and sewage sludge in China were analyzed and an annual inventory of trace element inputs was developed. The results showed that atmospheric deposition was responsible for 43–85% of the total As, Cr, Hg, Ni and Pb inputs, while livestock manures accounted for approximately 55%, 69% and 51% of the total Cd, Cu and Zn inputs, respectively. Among the elements concerned, Cd was a top priority in agricultural soils in China, with an average input rate of 0.004 mg/kg/yr in the plough layer (0–20 cm). Due to the spatial and temporal heterogeneity of the sources, the inventory as well as the environmental risks of trace elements in soils varies on a regional scale. For example, sewage sludge and fertilizers (mainly organic and phosphate-based inorganic fertilizers) can also be the predominant sources of trace elements where these materials were excessively applied. This work provides baseline information to develop policies to control and reduce toxic element inputs to and accumulation in agricultural soils.     

莱芜大气污染源排放颗粒物中多环芳烃研究

为了解莱芜市大气污染源排放颗粒物中多环芳烃的浓度及影响因素,采集机动车尾气尘、扬尘、工业燃煤颗粒物、民用燃煤颗粒物等4种样品,分别测定多环芳烃的含量。结果表明,莱芜市大气环境颗粒物中多环芳烃主要来源于机动车尾气和民用燃煤,12种多环芳烃类值分别为(1 536. 48±0. 78)和(299. 83±0. 30)μg/g,机动车尾气尘与扬尘、民用燃煤、工业燃煤多环芳烃均存在显著性差异。不同组分中,苯并(ghi)苝的值最高,为(559. 96±7. 59)μg/g,其次为晕苯,为(445. 36±5. 94)μg/g,城市空气污染呈现煤烟和机动车尾气复合污染的特点。     

水库淹没区耕地生态服务功能价值估算研究——以黄金坪水电站为例

以黄金坪水电站为例,采用碳税法、造林成本法以及工业氧价格替代法计算气体调节功能价值,并采用其它多种方法计算水土保持价值,以估算水库淹没区耕地生态服务功能价值。通过研究,使水库淹没区耕地总价值构成及量化趋于合理,为进一步完善淹没区耕地补偿构成和补偿标准提供参考。     

区域贸易协定中的多边环境协议所涉问题浅析

区域贸易协定框架下的多边环境协议涉及的主要问题可以概括为RTAs的环境条款类型、制度基础与制度选择问题,RTAs环境影响评价问题,RTAs的环境合作问题,RTAs环境标准、环境法实施与争端解决机制问题以及RTAs的公众参与环境保护问题等。贸易与环境问题的结合一直具有争议性,区域贸易协定在文本上达成的环境标准与贸易的结合要得到真正的实施,后续的努力至关重要,这些努力包括环境对话与合作、环境保护资金来源、公众参与等。     

Heavy metal (Cu, Zn, Cd and Pb) contamination of vegetables in urban India: a case study in Varanasi

The contributions of heavy metals in selected vegetables through atmospheric deposition were quantified in an urban area of India. Deposition rate of Zn was recorded maximum followed by Cu, Cd and Pb. The concentrations of Zn and Cu were highest in Brassica oleracea, Cd in Abelmoschus esculentus and B. oleracea, while Pb was highest in Beta vulgaris. Heavy metal pollution index showed that B. oleracea was maximally contaminated with heavy metals followed by A. esculentus and then B. vulgaris. The results of washing showed that atmospheric deposition has contributed to the increased levels of heavy metals in vegetables. Both Cu and Cd posed health risk to local population via test vegetables consumption, whereas Pb posed the same only through B. oleracea. The study concludes that atmospheric depositions can elevate the levels of heavy metals in vegetables during marketing having potential health hazards to consumers.     

Relationship between variations of Be, Pb and Pb concentrations and sub-regional atmospheric transport: Simultaneous observation at distant locations

In order to investigate the applicability of ²¹²Pb as a tracer for atmospheric transport in the sub-regional scale (few hundred kilometers in horizontal direction and up to ∼1 km by height), we measured the air concentrations of the short-lived radionuclide ²¹²Pb along with the long-lived ⁷Be and ²¹⁰Pb near the ground surface. For this purpose, simultaneous observations were continued for several days at three locations: a reference point representative for standard land surface atmosphere conditions, a second location at an altitude 650 m near the reference point, and on a solitary island ∼180 km from the reference point. Measurements of radioactivity in aerosol particle samples collected at intervals of 2-3 h with a high-volume air sampler were performed by extremely low background gamma-ray spectrometry with the use of Ge detectors located at the Ogoya Underground Laboratory. Concentration of ⁷Be or ²¹⁰Pb and their variation patterns was found to be similar among the three points during the whole observation period except for moment of the passage of a cold front. The results indicate that distributions of concentrations of the long-lived nuclides were uniform in this range. On the other hand, concentration levels and the variation patterns of the short-lived ²¹²Pb differed greatly from one location to another, reflecting differences in geographical location and altitude of the observation points. Additionally, there were certain indications that observed concentration of ²¹²Pb contained two components: an autogenous component from sources nearby and a heterogenous one from faraway sources carried by atmospheric horizontal transport. Results of this study provide experimental proof that ²¹²Pb can be used as a tracer of sub-regional atmospheric transport.     

环境影响评价类型的发展

通过对区域环境影响评价（ＲＤＥＩＡ）及累积影响评价（ＣＩＡ）、战略影响评价（ＳＥＡ）的产生原因、概念、研究方法，研究状况等方面的介绍及与项目ＥＩＡ的比较，说明ＲＤＥＩＡ、ＣＩＡ、ＳＥＡ的兴起是实行可持续发展战略的要求．     

重庆市金子山—黑石子小区大气环境规划研究

区域气象特征是造成重庆大气污染严重的重要原因。在实测模式参数基础上，较好地拟合了区域大气污染浓度的分布，并以此提出改善重庆市城区大气环境质量及发展小区经济、保证小区和市区大气环境质量的环境规划意见。