Growing interest in the application of stoichiometric approaches to community ecology has resulted in an increasing number of studies examining invertebrate body composition. Our experiments demonstrate various sources of possible error related to the use of pre-analytical procedures. We examined the effects of different preservatives (ethanol and formaldehyde) used in pitfall traps, time of preservation (2 weeks or 3 days) and drying method (vacuum drying at 50 °C and freeze-drying) on the determination of body composition in invertebrates representing taxa often used in such studies: earthworms and five species of insects (adults or larvae). The contents of C, N, S, P, Fe, Zn, Cu, Mn, Ca, Mg and K in each animal were measured. The use of solvents (ethanol or formaldehyde) in pitfall traps and for preservation significantly affects the body composition and stoichiometry of earthworms, even during short exposure times. Insects (both adults and larvae) were affected only during a 2-week exposure; 3 days of exposure did not significantly change their chemical composition. Vacuum-oven drying of animals at 50 °C does not affect their body composition relative to freeze-drying.

中文翻译：

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分析前处理对无脊椎动物化学计量测量结果的影响

对将化学计量方法应用于社区生态学的兴趣日益浓厚，导致越来越多的研究检查无脊椎动物的身体成分。我们的实验证明了与使用预分析程序相关的各种可能错误来源。我们研究了陷阱陷阱中使用的不同防腐剂（乙醇和甲醛）、保存时间（2 周或 3 天）和干燥方法（50 °C 真空干燥和冷冻干燥）对无脊椎动物身体成分测定的影响代表此类研究中常用的分类群：蚯蚓和五种昆虫（成虫或幼虫）。测定每只动物的C、N、S、P、Fe、Zn、Cu、Mn、Ca、Mg和K的含量。在陷阱陷阱和保存中使用溶剂（乙醇或甲醛）会显着影响蚯蚓的身体成分和化学计量，即使在很短的暴露时间内也是如此。昆虫（成虫和幼虫）仅在 2 周暴露​​期间受到影响；暴露3天并没有显着改变它们的化学成分。与冷冻干燥相比，在 50 °C 下真空干燥动物不会影响它们的身体成分。