New concepts in ecological risk assessment: where do we go from here?   总被引：10，自引：0，他引：10  

Solomon KR  Sibley P 《Marine pollution bulletin》2002,44(4):279-285

Through the use of safety factors, the use of single-species test data has been adequate for use in protective hazard assessments and criteria setting but, because hazard quotients do not consider the presence of multiple species each with a particular sensitivity or the interactions that can occur between these species in a functioning community, they are ill-suited to environmental risk assessment. Significant functional redundancy occurs in most ecosystems but this is poorly considered in single-species tests conducted under laboratory conditions. A significant advance in effects assessment was the use of the microcosm as a unit within which to test interacting populations of organisms. The microcosm has allowed the measurement of the environmental effect measures such as the NOAEC(community) under laboratory or field conditions and the application of this and other similarly derived measures to ecological risk assessment (ERA). More recently, distributions of single-species laboratory test data have been used for criteria setting and, combined with distributions of exposure concentrations, for risk assessment. Distributions of species sensitivity values have been used in an a priori way for setting environmental quality criteria such as the final acute value (FAV) derived for water quality criteria. Similar distributional approaches have been combined with modeled or measured concentrations to produce estimates of the joint probability of a single species being affected or that a proportion of organisms in a community will be impacted in a posteriori risk assessments. These techniques have not been widely applied for risk assessment of dredged materials, however, with appropriate consideration of bioavailability and spatial and nature of the data these techniques can be applied to soils and sediments.  相似文献   

Geochemistry and SHRIMP U‐Pb Zircon Dating of Mafic Rocks North of Zunhua City,Eastern Hebei,North China Craton: Paleoproterozoic Gabbro rather than Neoarchean Ophiolite     

XIE Hangqiang  DONG Chunyan  Alfred KR?NER  LIU Shoujie  BAI Wenqian  LIU Dunyi  WAN Yusheng 《《地质学报》英文版》2018,92(3):1024-1040

Abundant mafic-ultramafic blocks and dikes occur in the area north of Zunhua City, eastern Hebei Province, and were previously suggested to be part of a late Archean ophiolitic assemblage. We employed SHRIMP zircon dating and a geochemical study on these mafic and surrounding rocks to test the ophiolite hypothesis. The SHRIMP data suggest that three metagabbro samples were metamorphosed at ～1.8 Ga. Numerous ～2.5 Ga zircons display strong oscillatory zoning, characteristic of zircons from granitoid rocks but not from gabbro, so we suggest that these are xenocrystic grains. The age of these xenocrystic zircons and their metamorpbic rims suggests that these mafic blocks formed in Paleoproterozoic. The surrounding gneiss of intermediate composition also contains 2.5 Ga zircons with oscillatory zoning and 1.8 Ga metamorphic rims. Fractionated REE patterns and Nb, Ta, Zr, Hf negative anomalies to variable extent were observed in the mafic blocks and surrounding rocks, also supporting a significant difference in the chemistry of ophiolitic rocks. Our data suggest that many mafic blocks in northern Zunhua are not part of a late Archean ophiolite complex but part of a tectonically dismembered Paleoproterozoic intrusive gabbro complex. This study shows that late Paleoproterozoic metamorphism occurred in the western part of eastern Hebei Province.  相似文献   

河南省墒情预报业务服务系统   总被引：5，自引：0，他引：5  

刘荣花  朱自玺  邓天宏  方文松  付祥军 《气象》2005,31(8):77-80

在以往对作物不同生育阶段的耗水规律、适宜水分、干旱指标和农田土壤水分变化规律进行了大量研究工作的基础上,根据农业生产可持续发展的需要,开发研制了集河南省农田水分监测、预报和灌溉决策服务于一体的土壤墒情预报业务服务系统。该系统可较准确地预报未来一个月内的土壤墒情变化,并可根据作物发育特点,给出以最高产量和最佳经济效益为目标的灌溉建议。  相似文献   

气候变暖对河南省蚱蝉始鸣期的影响     

韩小梅申双和  刘荣花 《气候变化研究进展》2008,4(06):342-346

利用河南省驻马店、沈丘和太康3个农业气象观测站1990-2004年的蚱蝉物候观测资料和气象资料,研究了气候变暖对蚱蝉始鸣期的影响。结果表明：在气温升高的气候背景下,蚱蝉始鸣期呈提前趋势;3-6月平均气温对蚱蝉始鸣期有显著的影响,始鸣期与1月1日至平均始鸣期期间＞5℃有效积温关系最为密切。用积温法以5℃为发育起点温度,＞5℃初日为起始日期对各站蚱蝉始鸣期进行模拟和预报,其效果优于平均法。  相似文献   

The vertical hydraulic conductivity of an aquitard at two spatial scales   总被引：4，自引：0，他引：4  

Hart DJ  Bradbury KR  Feinstein DT 《Ground water》2006,44(2):201-211

Aquitards protect underlying aquifers from contaminants and limit recharge to those aquifers. Understanding the mechanisms and quantity of ground water flow across aquitards to underlying aquifers is essential for ground water planning and assessment. We present results of laboratory testing for shale hydraulic conductivities, a methodology for determining the vertical hydraulic conductivity (K(v)) of aquitards at regional scales and demonstrate the importance of discrete flow pathways across aquitards. A regional shale aquitard in southeastern Wisconsin, the Maquoketa Formation, was studied to define the role that an aquitard plays in a regional ground water flow system. Calibration of a regional ground water flow model for southeastern Wisconsin using both predevelopment steady-state and transient targets suggested that the regional K(v) of the Maquoketa Formation is 1.8 x 10(-11) m/s. The core-scale measurements of the K(v) of the Maquoketa Formation range from 1.8 x 10(-14) to 4.1 x 10(-12) m/s. Flow through some additional pathways in the shale, potential fractures or open boreholes, can explain the apparent increase of the regional-scale K(v). Based on well logs, erosional windows or high-conductivity zones seem unlikely pathways. Fractures cutting through the entire thickness of the shale spaced 5 km apart with an aperture of 50 microns could provide enough flow across the aquitard to match that provided by an equivalent bulk K(v) of 1.8 x 10(-11) m/s. In a similar fashion, only 50 wells of 0.1 m radius open to aquifers above and below the shale and evenly spaced 10 km apart across southeastern Wisconsin can match the model K(v).  相似文献   

基于CI指数的河南省近40a干旱特征分析   总被引：7，自引：0，他引：7  

李树岩  刘荣花  师丽魁  马志红 《干旱气象》2009,27(2):97-102

基于河南省113个气象站1970～2007实测气象资料,利用气象干旱综合指数对河南省近40 a的干旱特征进行了统计分析.首先计算了历史逐日的CI指数,统计近40 a各站点出现的干旱过程、各时段的干旱事件,在此基础上统计了河南省历年各地区干旱发生的频率、覆盖范围,分析了干旱发生范围的年际变化和不同强度干旱的空间分布特征.分析结果表明:河南省伏旱发生频率最高为63.6%,冬季干旱发生频率最低为48.8%,春旱和秋旱发生频率相近,分别为55.4%和56.9%;全省大范围干旱发生的年份春季和秋季较多分别有9 a,冬季最少只有5 a;春季豫北各等级干旱发生天数均较高,夏季和秋季全省易发生大范围轻旱,重旱发生较少,冬季轻旱和中旱呈显著的纬向分布,南少北多,和降水的分布有较好的负相关性.  相似文献   

1992-2006年河南省酸雨分布特征分析     

杜子璇  刘荣花  熊杰伟  邓伟  田宏伟  陆斌 《河南气象》2009,(1):55-58

利用南阳、商丘和郑州3个观测站1992-2006年酸雨观测数据进行统计,分析其15 a来年际、季节变化特征。结果表明：1992-1995年间,3站酸雨发生频率、降水年均pH值和酸雨雨量与全年雨量比值均呈现减弱趋势,1998-2006年间均出现加强趋势,且在期末明显变强;酸雨频率1、9和12月出现高值,pH值在9-12月份出现低值;1992-2000年由南到北酸雨区域逐渐变小,2000年后由南到北、由西到东酸雨区域迅速扩大。  相似文献   

气候变暖对河南省蚱蝉始鸣期的影响   总被引：1，自引：0，他引：1  

韩小梅  申双和  刘荣花 《气候变化研究进展》2008,4(6):342-346

 利用河南省驻马店、沈丘和太康3个农业气象观测站1990-2004年的蚱蝉物候观测资料和气象资料,研究了气候变暖对蚱蝉始鸣期的影响。结果表明：在气温升高的气候背景下,蚱蝉始鸣期呈提前趋势;3-6月平均气温对蚱蝉始鸣期有显著的影响,始鸣期与1月1日至平均始鸣期期间＞5℃有效积温关系最为密切。用积温法以5℃为发育起点温度,＞5℃初日为起始日期对各站蚱蝉始鸣期进行模拟和预报,其效果优于平均法。  相似文献   

河南省冬小麦干旱评估指标初探   总被引：9，自引：3，他引：6  

方文松  刘荣花  马志红  李树岩  师丽魁 《气象与环境科学》2008,31(3):5-14

利用3次多项式对河南省100多个县(市)历史冬小麦产量资料进行分解处理,求出趋势产量和气象产量,然后用相对气象产量与小麦不同发育阶段的降水距平百分率进行相关分析,结果发现,冬小麦相对气象产量与不同发育阶段的降水距平百分率具有一定的相关性.在此基础上,建立了冬小麦相对气象产量与降水距平百分率的回归方程,并与农业干旱划分标准相结合,确定了冬小麦不同发育阶段、不同干旱等级的干旱指标.  相似文献   

Mixed land use and obesity: an empirical comparison of alternative land use measures and geographic scales   总被引：1，自引：0，他引：1  

Yamada I  Brown BB  Smith KR  Zick CD  Kowaleski-Jones L  Fan JX 《The Professional geographer》2012,64(2):157-177

Obesity is a growing epidemic in the United States. Walkable neighborhoods, characterized as having the 3Ds of walkability (population Density, land use Diversity, and pedestrian-friendly Design), have been identified as a potentially promising factor to prevent obesity for their residents. Past studies examining the relationship between obesity and walkability vary in geographic scales of neighborhood definitions and methods of measuring the 3Ds. To better understand potential influences of these sometimes arbitrary choices, we test how four types of alternative measures of land use diversity measured at three geographic scales relate to body mass index for 4960 Salt Lake County adults. Generalized estimation equation models demonstrate that optimal diversity measures differed by gender and geographic scale and that integrating walkability measures at different scales improved the overall performance of models.  相似文献