Institute of Nature Conservation, Polish Academy of Sciences, al. Mickiewicza 33, 31-120 Kraków, Poland.
Institute of Nature Conservation, Polish Academy of Sciences, al. Mickiewicza 33, 31-120 Kraków, Poland.
Sci Total Environ. 2022 Sep 10;838(Pt 3):156354. doi: 10.1016/j.scitotenv.2022.156354. Epub 2022 May 29.
Macroplastic storage in mountain rivers remains unexplored and it is unknown how river morphology and different surface types of river areas modulate this process. Therefore, we sampled macroplastic debris stored on the surface of emergent river areas with different vegetation cover and on wood jams in a channelized, single-thread reach and an unmanaged, multi-thread reach of the Dunajec River in the Polish Carpathians. Total amounts of macroplastic debris retained in these reaches were then estimated on the basis of mean mass of macroplastic deposited on unit area of each surface type and the area of this surface type in a given reach. Exposed river sediments and areas covered with herbaceous vegetation stored significantly lower amounts of macroplastic debris (0.6 and 0.9 g per 1 m on average) than wooded islands and wood jams (respectively 6 g and 113 g per 1 m). The amounts of macroplastic debris stored on wood jams exceeded 19, 129 and 180 times those found on wooded islands, areas covered with herbaceous vegetation and exposed river sediments. Wooded islands and wood jams covering 16.7% and 1.5% of the multi-thread reach stored 43.8% and 41.1%, respectively, of the total amount of macroplastic stored in that reach, whereas these surface types were practically absent in the channelized reach. Consequently, the unmanaged, multi-thread reach, 2.4 times wider than the neighbouring channelized reach, stored 36 times greater amount of macroplastic per 1 km of river length. Our study demonstrated that the storage of macroplastic debris in a mountain river is controlled by channel management style and resultant river morphology, which modulate river hydrodynamics and a longitudinal pattern of the zones of transport and retention of macroplastic conveyed by river flow.
山区河流中的宏观塑料储存仍未得到探索，也不清楚河流形态和不同的河流区域表面类型如何调节这一过程。因此，我们在波兰喀尔巴阡山脉的 Dunajec 河的一个渠道化、单流河道和一个未管理的多流河道中，对不同植被覆盖的出露河流区域和木塞表面上储存的宏观塑料碎片进行了采样。然后，根据每种表面类型单位面积上沉积的宏观塑料的平均质量以及给定河段中该表面类型的面积，估算这些河段中保留的宏观塑料总量。与树木覆盖的岛屿和木塞（分别为每米 6 克和 113 克）相比，裸露的河流沉积物和草本植被覆盖的区域储存的宏观塑料碎片数量明显较少（平均每米分别为 0.6 和 0.9 克）。储存在木塞上的宏观塑料碎片数量分别超过树木覆盖的岛屿、草本植被覆盖的区域和裸露的河流沉积物的 19、129 和 180 倍。覆盖了 16.7%和 1.5%的多流河道的树木覆盖的岛屿和木塞储存了该河道中储存的宏观塑料总量的 43.8%和 41.1%，而这些表面类型在渠道化河道中几乎不存在。因此，未管理的多流河道比相邻的渠道化河道宽 2.4 倍，每公里河道长度储存的宏观塑料量增加了 36 倍。我们的研究表明，山区河流中宏观塑料碎片的储存受河道管理方式和由此产生的河流形态的控制，这些因素调节了河流水动力和由河流流动输送和滞留的宏观塑料的纵向分布模式。
