Dataset: Low-density microplastics (LD-MPs) in seven recreational parks of Al Ain, UAE isolated by density flotation method (DFM)

The LD-MPs from 104 soil samples collected from seven different recreational parks of Al Ain, UAE were isolated by DFM using saturated sodium chloride solution (1.2 g/cm3). A total of 10, 701 g of soil samples were processed for this study (Loc_Info_Micp_count.xlsx). Prior to extraction and isolation of MPs, the 10 ± 0.1 g of each sample were dried at 40 degrees Celsius for 24 hr and then filtered using a stack of 8" dm stainless steel sieves with aperture of 5 mm and 1mm. An aliquot of 5 ± 0.1 g were subjected for DFM. After that, the sample was filtered using a Whatman glass microfiber filter to separate LD-MPs from the liquid. The filter was then viewed under stereomicroscope. The physical characteristics of LD-MPs, such as size, color, and shape, were noted (Loc_info_Micp_count.xlsx). Microplastic concentration were determined and expressed as particles per kg of samples (Micp_conc_per_sampling_site.xlsx; Table 8). Statistical data of isolated LD-MPs sizes were computed (Stat_data_of_LD-MPs_size.xlsx; Table 9). The study also tried to correlate the LD-MPs concentrations with soil pH and moisture content. Results showed that there is a negative correlation in MPs concentrations and the two selected soil properties suggesting potential negative effects in soil health (Stat_data_soil_pH_moisture_content.xlsx; Tables 10 & 11). FTIR analyses were conducted to initially determine the possible polymers present in the isolated LD-MPs (SFig3_FTIR). Polymers identified were possibly polyethylene, polypropylene, polyethylene terephthalate, or polyvinyl chloride. These results found that the presence of LD-MPs in urban recreational parks might contribute to impending environmental negative effects.本研究从阿联酋艾因市7处不同休闲公园采集的104份土壤样本中，通过密度浮选法（DFM）结合密度为1.2 g/cm³的饱和氯化钠溶液，分离得到低密度微塑料（LD-MPs）。本研究共处理10701 g土壤样本（详见"Loc_Info_Micp_count.xlsx"）。在提取与分离微塑料前，每份称取10±0.1 g的土壤样本置于40℃烘箱中干燥24小时，随后使用孔径分别为5 mm与1 mm的8英寸不锈钢筛组进行筛分。称取5±0.1 g的等分试样用于密度浮选法处理。之后，使用Whatman玻璃微纤维滤膜对样本进行过滤，以分离液相中的低密度微塑料。随后将滤膜置于体视显微镜下观测。记录低密度微塑料的粒径、颜色与形状等物理特征（详见"Loc_info_Micp_count.xlsx"）。测定微塑料浓度，并以每千克土壤样本中的微塑料颗粒数为单位进行表征（详见"Micp_conc_per_sampling_site.xlsx"及表8）。对分离得到的低密度微塑料的粒径数据进行统计分析（详见"Stat_data_of_LD-MPs_size.xlsx"及表9）。本研究同时尝试分析低密度微塑料浓度与土壤pH值及含水率的相关性。结果显示，微塑料浓度与所选的两项土壤理化指标呈显著负相关，提示其可能对土壤健康存在潜在负面影响（详见"Stat_data_soil_pH_moisture_content.xlsx"及表10与表11）。采用傅里叶变换红外光谱（FTIR）对分离得到的低密度微塑料中的潜在聚合物成分进行初步鉴定（详见"SFig3_FTIR"）。鉴定得到的聚合物可能为聚乙烯、聚丙烯、聚对苯二甲酸乙二醇酯或聚氯乙烯。上述结果表明，城市休闲公园中存在的低密度微塑料可能会带来潜在的环境负面影响。