Arts Gertie H P, van Smeden Jasper, Wolters Marieke F, Belgers J Dick M, Matser Arrienne M, Hommen Udo, Bruns Eric, Heine Simon, Solga Andreas, Taylor Seamus
Environmental Risk Assessment, Wageningen University and Research, Wageningen, The Netherlands.
Fraunhofer Institute for Molecular Biology and Applied Ecology (Fraunhofer IME), Schmallenberg, Germany.
Integr Environ Assess Manag. 2024 Sep;20(5):1625-1638. doi: 10.1002/ieam.4916. Epub 2024 Mar 28.
Lemna L. sp. is a free-floating aquatic macrophyte that plays a key role as a standard test species in aquatic risk assessment for herbicides and other contaminants. Population modeling can be used to extrapolate from laboratory to field conditions. However, there are insufficient data on longer-term seasonal dynamics of this species to evaluate such models. Therefore, several long-term growth experiments were conducted in outdoor microcosms (surface area 0.174 m). Monitoring parameters included biomass, frond numbers, water parameters, and weather data. Three different datasets were generated: frond numbers and biomass from weekly to monthly destructively sampled microcosms; a year-round dataset of frond numbers from five continuously monitored microcosms; and seasonal growth rates without the effect of density dependence over 1-2 weeks in freshly inoculated microcosms. Lemna sp. reached a maximum of approximately 500 000 fronds m and 190 g dry weight m. During the first winter, the microcosms were covered by ice for approximately four weeks, and Lemna sp. populations collapsed. The second winter was warmer, without any ice cover, and Lemna sp. populations maintained high abundance throughout the winter. Dry weight per frond was not constant throughout the year but was highest in autumn and winter. Growth rates without density dependence under outdoor environmental conditions reached 0.29 day for frond number, 0.43 day for fresh weight, and 0.39 day for dry weight. In linear regressions, these growth rates were best explained by water temperature. For the populations continuously monitored throughout a year, the nitrogen-to-phosphorus ratio best explained the growth rate of frond numbers. This study yielded a relevant dataset for testing and refining Lemna population models used in chemical risk assessment as well as for managing ecosystems and combating the effects of eutrophication. Integr Environ Assess Manag 2024;20:1625-1638. © 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
浮萍属植物是一种漂浮于水面的水生大型植物，在除草剂和其他污染物的水生风险评估中作为标准测试物种发挥着关键作用。种群建模可用于从实验室条件外推至田间条件。然而，关于该物种长期季节动态的数据不足，无法评估此类模型。因此，在室外微宇宙（表面积0.174平方米）中进行了多项长期生长实验。监测参数包括生物量、叶状体数量、水质参数和气象数据。生成了三个不同的数据集：来自每周至每月进行破坏性采样的微宇宙的叶状体数量和生物量；来自五个连续监测的微宇宙的全年叶状体数量数据集；以及在新接种的微宇宙中1 - 2周内不受密度依赖性影响的季节性生长速率。浮萍属植物的叶状体数量最多达到约500000个/平方米，干重达到190克/平方米。在第一个冬季，微宇宙被冰覆盖了约四周，浮萍属植物种群崩溃。第二个冬季较为温暖，没有任何冰覆盖，浮萍属植物种群在整个冬季都保持着高丰度。每个叶状体的干重并非全年恒定，而是在秋季和冬季最高。在室外环境条件下，不受密度依赖性影响的生长速率对于叶状体数量为0.29/天，鲜重为0.43/天，干重为0.39/天。在线性回归中，这些生长速率最好用水温来解释。对于全年连续监测的种群，氮磷比最能解释叶状体数量的生长速率。本研究产生了一个相关数据集，用于测试和完善化学风险评估中使用的浮萍种群模型，以及用于管理生态系统和应对富营养化的影响。《综合环境评估与管理》2024年；20:1625 - 1638。© 2024作者。由威利期刊有限责任公司代表环境毒理学与化学学会（SETAC）出版的《综合环境评估与管理》
