南水北调中线工程水源地的土壤可蚀性特征

选定南水北调中线工程水源地丹江口水库区这一国家水土流失重点治理区域为研究地点,对该地的土壤可蚀性特征进行了研究。在研究区不同土地覆盖类型里采取表层(20 cm)土壤样品,室内分析样品土壤的质地和有机质含量,利用EPIC模型及实验室分析的土壤质地和有机质数据计算样品土壤可蚀性K值。在ARCGIS里,利用Ordinary Kriging插值方法生成研究区K值分布图。然后按一定标准将K值进行分级,得出不同K等级值的空间分布及面积。结果表明：研究区K的均值为0034 8（ t·hm2·h）/（hm2·MJ·mm）,主要为中可蚀性土壤(面积占91.71%)。东部(主要是耕地)土壤K值高于西部(主要是林地),是侵蚀治理的重点地区。研究结果可为库区水土流失定量遥感监测提供基础资料,对库区的土壤侵蚀治理有一定的参考作用     

VB可视化集成环境下空气污染指数计算与分析系统

探讨了以VB可视化集成环境为平台，在Windows操作系统下开发空气污染指数计算与分析系统的基本模型和方法，指出开发空气污染指数计算与分析系统的关键是建立可视化用户界面和相应的事件驱动过程的代码编写，阐述了空气污染指数计算与分析系统的优越性，列出了系统功能的主要内容和开发方法，并且简单介绍了空气污染指数的算法。     

Reconciling food and bioenergy feedstock supply in emerging economies: Evidence from Jiangsu Province in China

This study takes the perspective of emerging economies as an independent group to answer the question of how to reconcile food supply and bioenergy feedstock provision, a critical topic in bioenergy research. While much of the literature has covered this issue, the role of emerging economies has rarely been explored. Due to their transitional status in the world economy, solutions from this group can facilitate the diffusion of modern bioenergy from industrialized countries to least developed ones. This paper uses Jiangsu Province in China as a case study to analyze its local practice on the reconciliation between food and bioenergy. Local experience reveals that the key is the use of cellulosic biomass, whose sources are straws of food crops on arable lands and energy crops on reclaimed mudflats. To ensure a sustainable provision of cellulosic biomass, it is necessary to involve the entire bioenergy supply chain consisting of smallholder farmers, haulers and bioenergy plant operators. For the management of the supply chain, we compare two options, “Multiple to Multiple” and “Multiple to One”, where the second option is more adequate to shape a long-term stable relationship between biomass suppliers and consumers and thus facilitate the introduction of energy crops.     

土壤DDT残留时间的定量表征-以天津为例

从定性研究逐步向定量化分析发展,是土壤DDT残留时间研究的必然趋势。初步探讨了土壤中DDT残留时间的定量表征,设计出归一化的DDT残留时间指数(NRTI)作为定量表征土壤DDT残留时间的方法之一。根据对天津土壤中残留DDT的采样监测结果的计算和分析,发现NRTI在表征DDT的残留时间问题上,相对于传统方法有一定的改进。     

基于水土保持下的生态补偿机制分析

目前,我国生态补偿机制依旧存在法规不健全、体系不科学的问题,无法满足当下水土保持工作的整体要求。本文主要针对当下生态补偿机制存在的问题,阐明建立健全生态补偿机制的必要性,并进一步提出相应的机制完善措施,以望为未来水土保持工作提供参考。     

Distributions, sources, and ecological risks of hexachlorocyclohexanes in the sediments from Haihe Plain, Northern China

The levels of hexachlorocyclohexanes (HCHs) in the sediments from Haihe Plain, China, were measured by a gas chromatograph with a ⁶³Ni microelectron capture detector. The spatial distributions, possible sources, and potential ecological risks of these compounds were analyzed. The residual level of total HCHs was 33.84?±?173.37 ng?g^?1 dry weight (d.w.) with ranges of 0.13?～?1,107.41 ng?g^?1 d.w. Much higher ΣHCH contents were found in the lower reaches of some rivers and in the mouth of the main stream receiving tributaries. The predominance of β-HCH (36 %) in the sediments was similar to that in the soils from Haihe Plain. The high percentages of γ-HCH (23–41 %) could be detected at 25 % of the sampling sites in the seven river systems. There were statistically significant positive relationships between the contents of HCHs and total organic carbon. Lindane was identified as the primary source of HCHs in the sediments, and it seemed that recent illegal lindane inputs still existed in some areas in Haihe Plain, as indicated by the α-/γ-HCH and β-/(α?+?γ)-HCH ratios. Severe potential ecological risks of γ-HCH to benthic organisms at some sampling sites were found based on the consensus-based sediment quality guidelines.     

Socio-economic Impacts on Flooding: A 4000-Year History of the Yellow River, China

We analyze 4000-year flood history of the lower Yellow River and the history of agricultural development in the middle river by investigating historical writings and quantitative time series data of environmental changes in the river basin. Flood dynamics are characterized by positive feedback loops, critical thresholds of natural processes, and abrupt transitions caused by socio-economic factors. Technological and organizational innovations were dominant driving forces of the flood history. The popularization of iron plows and embankment of the lower river in the 4th century BC initiated a positive feedback loop on levee breaches. The strength of the feedback loop was enhanced by farming of coarse-sediment producing areas, steep hillslope cultivation, and a new river management paradigm, and finally pushed the flood frequency to its climax in the seventeenth century. The co-evolution of river dynamics and Chinese society is remarkable, especially farming and soil erosion in the middle river, and central authority and river management in the lower river.     

基于模糊综合评判的汶川8.0级地震重灾区滑坡泥石流气候风险评估

用1971-2000年的30年逐日降水量资料,按旬统计汶川地震重灾县5-12月各旬的雨日、中雨日、大雨日、暴雨日的平均日数和气候概率,根据地震重灾区实际地质环境条件,降低强降雨强度条件,基于模糊综合评判法,按照最大隶属度原则对汶川特大地震重灾区的39个县进行地质灾害时空气候风险评估。结果表明:重灾区的地质灾害气候风险指数值存在两个高值期间,一个是5月中旬至7月上旬,另一个是8月下旬至9月下旬。而10月下旬至次年4月,重灾区降雨明显减少,绝大部分地区没有地质灾害气候风险;从地域分布来看,高风险区域主要集中在重灾区的西部和中部,风险等级为3～4级(风险较大或很大),东部地区风险等级为1～2级(中等风险或风险较小),但7月下旬高等级风险区位置集中在重灾区的南部和东部。     

煤气发生炉炉渣改性和吸附性能

以工业中生产煤气时产生的煤气炉炉渣为原料,采用手工分选法将炉渣中的炭及残渣分离,再采用酸碱浸渍方法对炉渣残渣进行改性,研究了改性后的炉渣残渣及炉渣中分离出的炭对溶液中苯酚的吸附性能。吸附实验结果表明,分离炭的吸附性能最好,其次为碱改性炉渣残渣和酸改性炉渣残渣,未改性炉渣残渣吸附性能最差。改性的炉渣残渣及分离炭对苯酚吸附过程符合二级吸附动力学模型。吸附等温线研究表明,改性炉渣残渣及分离炭对苯酚的吸附符合Lang-muir吸附等温式。