PDF(Pubmed)
Abstract：
The main aimed of this study was to provide information on microplastics present in the freshwater of fish farm ponds. In addition, the study showes a relationship between the seasonal, spatial distribution and the amount of microplastics found. This study was conducted in 35 fish farms located in the Rondônia state, Brazil, the sample collects were carried out in the two Amazonian hydrological seasons (dry and rainy). The study was developed in a completely randomized factorial scheme 35 × 3 x 3 (35 fish farms, 3 ponds and 3 repetitions per ponds). Microplastic sampling was performed following a modified method based on National Oceanic and Atmospheric Administration (NOAA). Samples of 250 mL freshwater collected, which were deionized and pre-filtered through 6.0 mm mesh granulometric sieves. The average abundances of the different hydrological seasons were compared by Student\'s t-test, with differences statistically significant at p < 0.05. The microplastics were morphological categorized into fibers and colors blue, red or transparent. Microplastic contamination was confirmed in freshwater of 9 fish farming, with greater abundance of blue fibers and greater quantification in the rainy season. Fish farms P3, P4 and P6 had the highest quantifications of blue fiber in the two seasons (6 and 43, 19 and 56, 11 and 88 items mL-1, respectively). Almost all fish farms had a higher abundance of microplastics in the rainy season. It is important to highlight the prominence of microplastics in the blue fiber rainy season (286 items mL-1) compared to the dry season (58 items mL-1). Fish farms P3, P4 and P6 showed a strong positive correlation between the factors distance from the nearest urban area (r = 0.94, 0.79 and 0.97, respectively) and seasonality (r = 0.98, 0.77 and 0.96, respectively). Rainfall variations influenced the abundance of microplastics, especially of blue fibers. Fish farms are supplied with fresh water by rivers or streams, so it is possible that microplastics originate outside the fish farm, perhaps they were introduced due to high soil occupation, although surface runoff (of water contaminated by sewage) caused by heavy rains the most important factor. Therefore, one factor must be considered, surface runoff and groundwater contaminated by urban, agricultural and urban effluents may have contaminated rivers and streams and then contaminated the water in the fish farm ponds.
摘要：
这项研究的主要目的是提供有关养鱼场池塘淡水中存在的微塑料的信息。此外,这项研究展示了季节性之间的关系，空间分布和发现的微塑料数量。这项研究是在位于朗多尼亚州的35个养鱼场进行的，巴西,样品收集是在两个亚马逊水文季节（干旱和多雨）进行的。这项研究是在一个完全随机的因子方案35×3×3(35个养鱼场，3个池塘，每个池塘3次重复）。微塑料采样是根据美国国家海洋和大气管理局（NOAA）的改进方法进行的。收集的250毫升淡水样本，将其去离子并通过6.0mm目筛预过滤。用学生t检验比较不同水文季节的平均丰度，在p<0.05时，差异具有统计学意义。微塑料在形态上分为纤维和蓝色，红色或透明。在9种鱼类养殖的淡水中确认了微塑料污染，在雨季，蓝色纤维的丰度更高，量化更高。在两个季节中，养鱼场P3，P4和P6的蓝纤维定量最高（分别为6和43、19和56、11和88项mL-1）。在雨季，几乎所有的养鱼场都有更多的微塑料。重要的是要强调微塑料在蓝色纤维雨季（286项mL-1）相对于旱季（58项mL-1）的突出性。养鱼场P3，P4和P6显示出与最近市区距离的因素（分别为r=0.94，0.79和0.97）与季节性（分别为r=0.98，0.77和0.96）之间的强正相关。降雨变化影响了微塑料的丰度，尤其是蓝色纤维。养鱼场由河流或溪流提供淡水，所以微塑料可能起源于养鱼场之外，也许它们是由于高土壤占用而引入的，虽然地表径流(污水污染的水)是暴雨造成的最重要因素。因此,必须考虑一个因素，被城市污染的地表径流和地下水，农业和城市废水可能污染了河流和溪流，然后污染了养鱼场池塘中的水。
