岩溶高原区农业地膜中邻苯二甲酸二乙基己酯的释放及其对覆膜土壤的影响

朱丹尼; 邹胜章; 周长松; 刘菲; 谢浩; 卢海平

doi:10.15898/j.cnki.11-2131/td.201808150095

岩溶高原区农业地膜中邻苯二甲酸二乙基己酯的释放及其对覆膜土壤的影响

Release of Di-(2-ethylhexyl) Phthalate from Agricultural Plastic Film in the Karst Plateau Area and Its Effect on Film-covered Soil

摘要

摘要: 随着邻苯二甲酸酯类（PAEs）增塑剂在塑料大棚、地膜覆盖栽培技术中的广泛应用，我国农业土壤中已普遍存在邻苯二甲酸二乙基己酯（DEHP）污染问题。针对我国中西部岩溶高原区农业土壤中存在的DEHP环境问题，本文选取云南岩溶高原区的红壤及烟草地膜作为研究对象，通过田间试验模拟覆膜土壤环境，并采用气相色谱-质谱分析法检测农膜、土壤介质中DEHP含量，定量研究了地膜中DEHP的释放及其在覆膜土壤中的浓度分布特征。结果表明：覆盖于原状土壤上的地膜，其DEHP释放量最大，均值为13.57mg/kg；覆盖于加生物抑制剂土壤上的地膜，其DEHP释放量略高于未覆土壤地膜，前者DEHP平均值为10.83mg/kg，后者为10.77mg/kg；地膜中DEHP的释放表现为缓慢释放和集中陡升两个释放段，总体释放量随时间的延长而增加。两组覆膜土壤中DEHP的检出浓度范围分别为0.17~3.74mg/kg（原状土）、0.34~4.29mg/kg（加生物抑制剂土壤），在国内外覆膜农田土壤PAEs类化合物检出浓度范围内；土壤中DEHP含量具有随时间呈先增后减的变化规律。相关性分析表明土壤中DEHP主要来自于地膜中DEHP的释放。研究认为在短周期内岩溶高原红壤不会出现DEHP的累积，合理安排农作物的覆膜种植可有效削减土壤的有机污染。

Abstract:
BACKGROUNDWith the wide application of PAEs in plastic greenhouse and plastic film mulching cultivation techniques, the pollution of diethylhexyl phthalate (DEHP) in agricultural soils has become widespread in China.
OBJECTIVESTo quantitatively reveal the release of DEHP from plastic film and the distribution characteristics of DEHP concentration in mulched soil, red soil and tobacco films in the Yunnan Karst Plateau.
METHODSField experiments were conducted to simulate the mulched soil environment, and the DEHP contents in agricultural film and soil media were determined by Gas Chromatography-Mass Spectrometry.
RESULTSThe maximum release of DEHP from plastic film cover in undisturbed soil was 13.57mg/kg. The average DEHP (10.83mg/kg) released from plastic film covered with biological inhibitors was slightly higher than that from uncovered soil (10.77mg/kg). The releases of DEHP from plastic film included two stages of slow release and concentrated steep increase. The total release increased with time. DEHP concentrations in undisturbed soil ranged from 0.17 to 3.74mg/kg and those in soil with biological inhibitors ranged from 0.34 to 4.29mg/kg. The DEHP levels were within the detection concentration range of phthalate esters (PAEs) in mulched farmland soil at home and abroad. The contents of DEHP in soils increased first and then decreased with time.
CONCLUSIONSDEHP in soil mainly comes from the release of DEHP in plastic film. It is concluded that DEHP does not accumulate in red soils of the Karst Plateau within a short period. Reasonable arrangement of crop mulching can effectively reduce organic pollution in soil.

HTML全文

参考文献(32)

施引文献

资源附件(0)