Department of Ecology and Coastal Management, Institute of Marine Sciences of Andalusia, Cádiz, Spain.
Faculty of Marine and Environmental Sciences, University of Cadiz, Cádiz, Spain.
Environ Toxicol Chem. 2018 Dec;37(12):3095-3101. doi: 10.1002/etc.4277. Epub 2018 Nov 15.
Bioassays using the nonforced exposure approach have been shown to be a relevant tool that might complement the traditional ecotoxicological risk assessment. Because the nonforced exposure approach is based on spatial displacement of organisms and the consequent habitat selection processes, the population density might play an important role in the decision to avoid or prefer an ecosystem. Therefore, the aim of the present study was to assess if the avoidance response to contamination, measured in a nonforced exposure system, is density-dependent and how determinant contamination could be for the habitat-selection process in comparison with the population density. The freshwater shrimp Atyaephyra desmarestii was exposed to a copper gradient in a nonforced exposure system formed by 7 interconnected compartments (total volume 600 mL), which contained different copper concentrations. The density treatments used were 3, 5, and 10 organisms per compartment, corresponding to 0.5, 0.8, and 1.7 organisms per 100 mL, respectively. Clearly, the avoidance response to copper was more intense in the population with the lower density: the highest population density showed the lowest avoidance. The concentrations that triggered an avoidance of 50% of the population were 47, 134, and 163 μg L . In summary, it was observed that shrimps were able to detect and avoid potentially toxic copper concentrations but that the avoidance response was affected by population density. Environ Toxicol Chem 2018;37:3095-3101. © 2018 SETAC.
生物测定采用非强制暴露方法已被证明是一种相关工具，可能会补充传统的生态毒理学风险评估。由于非强制暴露方法基于生物体的空间位移和随之而来的栖息地选择过程，种群密度可能在避免或偏好生态系统的决策中发挥重要作用。因此，本研究的目的是评估在非强制暴露系统中测量的对污染的回避反应是否与密度有关，以及与种群密度相比，污染对栖息地选择过程的决定性有多大。淡水虾 Atyaephyra desmarestii 在非强制暴露系统中暴露于铜梯度中，该系统由 7 个相互连接的隔室（总容积 600 mL）组成，其中包含不同的铜浓度。使用的密度处理分别为每个隔室 3、5 和 10 个生物体，分别对应于每个 100 mL 中的 0.5、0.8 和 1.7 个生物体。显然，种群密度较低时，对铜的回避反应更为强烈：种群密度最高时，回避率最低。引发种群回避率为 50%的浓度分别为 47、134 和 163 μg L 。总之，观察到虾能够检测到并避免潜在的有毒铜浓度，但回避反应受到种群密度的影响。环境毒理化学 2018；37:3095-3101。 © 2018 SETAC。
