A Comparison of Single and Multiple Habitat Protocols for Collecting Macroinvertebrates in Wadeable Streams1

Abstract: In 2003, we compared two benthic macroinvertebrate sampling methods that are used for rapid biological assessment of wadeable streams. A single habitat method using kick sampling in riffles and runs was compared to a multiple habitat method that sampled all available habitats in proportion of occurrence. Both methods were performed side‐by‐side at 41 sites in lower gradient streams of the Piedmont and Northern Piedmont ecoregions of the United States, where riffle habitat is less abundant. Differences in sampling methods were examined using similarity indices, two multimetric indices [the family‐level Virginia Stream Condition Index (VSCI) and the species‐level Macroinvertebrate Biotic Integrity Index (MBII)], their component metrics, and bioassessment endpoints based on each index. Index scores were highly correlated between single and multiple habitat field methods, and sampling method comparability, based on comparison of similarities between and within sampling methods, was particularly high for species level data. The VSCI scores and values of most of its component metrics were not significantly higher for one particular method, but relationships between single and multiple habitat values were highly variable for percent Ephemeroptera, percent chironomids, and percent Plecoptera and Trichoptera (Hydropsychidae excluded). A similar level of variability in the relationship was observed for the MBII and most of its metrics, but Ephemeroptera richness, percent individuals in the dominant five taxa, and Hilsenhoff Biotic Index scores all exhibited differences in values between single and multiple habitat field methods. When applied to multiple habitat samples, the MBII exhibited greater precision, higher index scores, and higher assessment categories than when applied to single habitat samples at the same sites. In streams with limited or no riffle habitats, the multiple habitat method should provide an adequate sample for biological assessment, and at sites with abundant riffle habitat, little difference would be expected between the single and multiple habitat field methods. Thus, in geographic areas with a wide variety of stream types, the multiple habitat method may be more desirable. Even so, the variability in the relationship between single and multiple habitat methods indicates that the data are not interchangeable, and we suggest that any change in sampling method should be accompanied by a recalibration of any existing assessment tool (e.g., multimetric index) with data collected using the new method, regardless of taxonomic level.     

构建自然灾害应急物流系统的思考

<正>在抗震救灾应急物流中的思考"5·12"汶川特大地震发生后,绍兴市民政系统快速反应,紧急部署,启动工作预案,纷纷捐款捐物,及时在媒体上公布捐赠热线和捐赠专用账户,与市直机关党工委联合发出向灾区捐款捐物的倡议。全局上下把抗震救灾工作作为一项重大政治任务,把接收捐赠作为支援灾区的实际行动,全力以赴,探索创新,保质保量及时完成帐篷、     

深基坑支护系统稳定性可靠度分析

尝试将系统可靠度理论运用于深基坑稳定性的可靠度分析，提出了基坑系统稳定性的可靠度模型。通过实例计算分析，验证了本方法的可行性。研究对今后基坑支护的设计具有一定的实际意义。     

厌氧反应器技术研究开发情况简介

本文分析了厌氧反应器技术的发展过程,着重介绍了几种新型第三代厌氧反应器技术的原理和应用现状,以及我国目前对这些技术的研究开展情况,其中:升流式厌氧污泥床过滤器(UBF)研究取得了一定的成功经验;垂直折流厌氧污泥床反应器(VBASBR)缺乏应用生产实例;厌氧折流反应器(ABR)已有成功经验;内循环反应器(IC)还只限于部分废水的处理;膨胀颗粒污泥床反应器(ECSB)尚未有规模的生产投入使用。     

Observation of black carbon aerosol in Beijing, 2003

The objective of this study was to determine the black carbon concentration in Beijing in 2003. The aerosol properties were measured using an Aethalometer and a tapered element oscillating microbalance (TEOM) on the roof of the Physics Building of Peking University (39.99° N, 116.31° E) from July to August 2003 and from November 2003 to January 2004. The average black carbon (BC) concentrations in the summer and winter were 8.80 and 11.4 μg/m³, respectively. During winter, two different cyclone cut offs were installed at the inlet of an aethalometer. The BC mass concentration in TSP, PM₁₀, and PM_2.5 were obtained. The results indicated that in winter aerosol, 90% of BC exited in PM₁₀ and 82.6% of BC exited in PM_2.5. The BC in PM₁₀ accounted for 5.11% of the PM₁₀ mass.     

The association between heavy metal soil pollution and stomach cancer: a case study in Hangzhou City,China

Stomach cancer (SC) is a severe health burden, with nearly half of the world’s cases found in China. Noticeably, the emissions of heavy metals into the environment have increased alongside rapid urbanization and industrialization in China. However, as regards carcinogenic associations, the relationship between heavy metals and SC is yet unclear. Based on 9378 newly diagnosed SC cases in Hangzhou City from 2009 to 2012, this work is concerned with the quantitative characterization of the spatial distribution pattern of SC incidence and its geographical association with soil heavy metals by means of a novel geographical model. The results show that (a) Cd is one of the severe soil pollutants in Hangzhou; (b) higher SC incidence clusters are in central Hangzhou, whereas lower clusters are found in the northeast and southwest with a male to female incidence ratio about 2.2:1; (c) although when considered separately, the heavy metals in this work do not have a considerable impact on the distribution of SC incidence in Hangzhou City, nevertheless, the joint effects of multiple heavy metals have significant impacts on SC risk. The present work calls for a rigorous quantitative assessment of the integrated heavy metal soil pollution and its effects on SC incidence.     

Occurrence of veterinary antibiotics in struvite recovery from swine wastewater by using a fluidized bed

Antibiotics in wastewater pose pharmacological threats to phosphorous recovery. Recovered struvite particles possessed significantly antibiotic residues. Smaller granules contained much more antibiotics than the larger ones. Organic matters and struvite granulation process exerted significant impacts. Recovering phosphorus from livestock wastewater has gained extensive attention. The residue of veterinary antibiotics in the wastewater may be present in the recovered products, thereby posing pharmacological threats to the agricultural planting and human health. This study investigated antibiotic occurrence in the struvite particles recovered from swine wastewater by using a fluidized bed. Results revealed that tetracyclines possessed significant residues in the struvite granules, with the values ranging from 195.2 mg·kg⁻¹ to 1995.0 mg·kg⁻¹. As for fluoroquinolones, their concentrations varied from 0.4 mg·kg⁻¹ to 1104.0 mg·kg⁻¹. Struvite particles were of various sizes and shapes and displayed different antibiotic adsorption capacities. The data also showed that the smaller granules contained much more antibiotics than the larger ones, indicating that the fluidized granulation process of struvite crystals plays an important role on the accumulation of antibiotics. For tetracyclines, organic matters and struvite adsorption exerted significant impacts on tetracyclines migration. The outcomes underscore the need to consider the residues of antibiotics in resource recovery from wastewater because they exert pharmacological impacts on the utilization of recovered products.