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Despite the uncontested significance of soils for human nutrition and drinking water quality, the majority of ecotoxicological testing is confined to aquatic test systems. Among the standardised tests for soils, the reproduction test with the springtail Folsomia candida is among the most widely used ones. First steps towards its standardisation were undertaken in the late 1980s. Here we review major advances that have been made since then, with respect to mechanistic, pragmatic and ecological aspects. Specifically we address the ecological relevance of any modifications of the standardised tests. We introduce a miniaturised version of the reproduction test which allows reducing the amount of soil per test unit to one third and the number of synchronised individuals to 40% as compared to the standard test. In addition, we developed an assay using Collembola eggs instead of synchronised adults. First results of a three-species test indicate that the presence of other species may affect choice behaviour. We point out a potential biased view of existing ecotoxicological data with Collembola due to the fact that most results refer to metal contamination. Finally, recommendations for future research are given, with special reference to avoidance and microcosm tests involving Collembola. 相似文献
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Dandan Zhu Jianglin Zhang Zheng Wang Rizwan Khan Muhammad Jianwei Lu Xiaokun Li 《Soil Use and Management》2019,35(3):503-510
Data from 147 field trials were collected to study the influence of straw incorporation on soil potassium (K) under an intensive rice–oilseed rape rotation system, while pot experiments were conducted to evaluate the effects of rice straw incorporation on soil K availability. A significant correlation was observed between the soil available K and the relative yield (RRY) and the relative K uptake (RKU) of oilseed rape, with R2 values ranging from 0.07 to 0.08 and from 0.10 to 0.11, respectively, when data were fitted to a logarithmic equation model. In approximately 30% of trials, RRY reached 90%, while soil test available K values were below the critical limit, indicating that soil K values at the time of sampling (within 1 week of rice harvest) underestimated the actual soil K supply capacity. The pot experiment results showed that soil available K was affected by straw incorporation and soil type in the fallow period. The NH4OAc‐K and NaBPh4‐K concentrations of soils increased at first, and then, plateaued after 28 days. Straw incorporation significantly influenced the critical soil K concentration, which is important for making accurate K fertilizer recommendation. These results suggested that straw K should be seriously considered in making K fertilizer recommendations. Extending the sampling time from 1 to 3 weeks after the harvesting of rice to stabilize the effects of straw incorporation may help achieve a more accurate evaluation of soil available K. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(2):220-230
Different relationships between soil-test methods results have been reported in several agricultural regions. Differences in the same soil-test procedure (e.g., soil/solution ratio) exist between soil-testing laboratories from different agricultural regions. Our objectives were to (1) determine the effect of soil/solution ratio on the amount of phosphorus removed by Bray 1 and Mehlich 3 methods, (2) compare the amounts of phosphorus removed by Bray 1 and Mehlich 3 in Mollisols from the Pampean region, and (3) determine whether soil/solution ratio affects the relationship between Bray 1 and Mehlich 3. Soil phosphorus availability was determined with two extractants (Bray 1 and Mehlich 3), using two soil/solution ratios (1:10 and 1:8, wt/v) in 72 soils (noncalcareous, loess-derived Molisolls) from the Pampean region. The amount of phosphorus removed was 20–24% greater when using 1:10 than 1:8 (wt/v) soil/solution ratio. This effect was significantly greater in Bray 1 than in Mehlich 3 (p = 0.04). When compared using the same soil/solution ratio, Mehlich 3 removed 4 to 8% more phosphorus than Bray 1. The soil/solution ratio used in the comparison affected the relationship between both extractants. The difference between extractants was slightly greater with a soil/solution ratio of 1:8 than of 1:10 (p = 0.03). Our results showed that even when using the same method, changes in the procedure (like soil/solution ratio) may cause different soil-test results and also differences in the relationship between two extracting solutions. Therefore, reported relationships between two methods are only valid for the soils and region where the relationship was developed and should not be extrapolated to other regions, even with similar soils. 相似文献
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为进一步提升实验室检测技术能力,加强实验室的质量管理,确保日常检验检测结果的准确性和可靠性,组织开展了全国省级兽药检验机构实验室间溶液pH值测定的能力验证。依据《中国兽药典》2015年版一部附录0631pH值测定法以及中国合格评定国家认可委员会(CNAS)规定的程序进行本次能力验证。采用单因子方差分析对制备的测试样品进行均匀性检验,采用t检验对样品进行稳定性考察,采用Z比分数评价各参加实验室的测试结果,以稳健统计的中位值作为指定值。参加本次能力验证的35家兽药检测实验室结果均为满意,表明承担兽药监督抽检和风险监测任务的单位整体具有较强的检验检测能力。 相似文献
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ASVCP guidelines: quality assurance for portable blood glucose meter (glucometer) use in veterinary medicine 下载免费PDF全文
Karen L. Gerber Kathleen P. Freeman 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2016,45(1):10-27
Portable blood glucose meters (PBGM, glucometers) are a convenient, cost effective, and quick means to assess patient blood glucose concentration. The number of commercially available PBGM is constantly increasing, making it challenging to determine whether certain glucometers may have benefits over others for veterinary testing. The challenge in selection of an appropriate glucometer from a quality perspective is compounded by the variety of analytic methods used to quantify glucose concentrations and disparate statistical analysis in many published studies. These guidelines were developed as part of the ASVCP QALS committee response to establish recommendations to improve the quality of testing using point‐of‐care testing (POCT) handheld and benchtop devices in veterinary medicine. They are intended for clinical pathologists and laboratory professionals to provide them with background knowledge and specific recommendations for quality assurance (QA) and quality control (QC), and to serve as a resource to assist the provision of advice to veterinarians and technicians to improve the quality of results obtained when using PBGM. These guidelines are not intended to be all‐inclusive; rather they provide a minimum standard for management of PBGM in the veterinary setting. 相似文献
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