Abstract：
River water was sampled at 105 locations in the Ottawa River watershed and analysed for microplastics. Sampling techniques were standardised and replicated at each sample location to give an indication of the spatial extent of microplastics at the watershed scale. Microplastic concentrations remained largely uniform, with no clear accumulation of microplastics towards the lower reaches of the watershed. An ANCOVA analysis determined that the only significant relationships to microplastic concentration were distance downstream on the main channel and tributaries and an increase of microplastic concentrations at boat launch locations. However, these relationships were not strong (R2 value of 0.15) and suggest a more complex interaction of microplastics in large watersheds. It is recommended that further research on microplastic pollution in rivers needs to also focus on temporal factors in addition to considering sinks as an important element in the distribution of microplastics at the watershed scale.
摘要：
在渥太华河流域的105个地点对河水进行了采样，并分析了微塑料。在每个样品位置对采样技术进行了标准化和复制，以指示分水岭尺度上微塑料的空间范围。微塑料浓度基本上保持均匀，在流域下游没有明显的微塑料积累。ANCOVA分析确定，与微塑料浓度的唯一重要关系是主要通道和支流下游的距离以及船下水位置微塑料浓度的增加。然而,这些关系并不牢固（R2值为0.15），表明大型流域中微塑料的相互作用更为复杂。建议对河流中微塑料污染的进一步研究除了考虑汇作为流域尺度微塑料分布的重要元素外，还需要关注时间因素。
