4种甘肃优势作物规模种植土壤农药残留及风险评估

Assessment of Pesticide Residue Risk in Soil Cultivated with Four Kinds of Advantageous Crops in Gansu Province.

甘肃是我国农产品的重要供应区,主要优势作物有道地中药材党参、典型高原夏菜花椰菜、优质马铃薯和制种玉米等。为了解这些作物规模种植土壤农药残留状况,采用色谱、质谱等检测手段对土壤中有机农药残留进行分析,结合非度量多维尺度方法解析不同作物土壤农药残留类型的空间差异,并运用风险商法(RQ)评估农药残留对土壤生物的环境风险。结果表明,除草剂乙草胺、莠去津和草甘膦均被检出,其检出含量分别为8.280~52.418、33.693~40.088和1.022~18.421μg·kg^(-1)。此外,在土壤中这3种除草剂的残留量较低。然而,不同作物规模种植土壤中农药残留的主要类型存在差异。乙草胺主要在党参种植区被检出,莠去津仅在玉米种植区被检出,而花椰菜、玉米和马铃薯种植区均主要检测到草甘膦。被检出的32种有机磷类农药含量范围为0.369~3845.028μg·kg^(-1)。有机磷类农药在党参种植区被广泛检出,而在花椰菜、玉米和马铃薯种植区则偶有检出。大部分有机磷类农药残留对土壤生物环境风险属于可接受范围(RQ值≤1)。在检测到的9种菊酯类农药中,溴氰菊酯检出含量范围为2.904~59.514μg·kg^(-1),该农药主要残留在马铃薯P2和花椰菜V3种植区土壤中。与其他菊酯类农药相比,溴氰菊酯具有较高的RQ值,但其土壤生物环境风险仍属于可接受范围。有2种有机氯类农药被检出,但其整体含量较低,土壤生物环境风险也处于可接受范围。研究区域土壤检出的残留农药类型较多,但农药残留量整体处于较低水平,并且土壤生物环境风险可接受,这有利于甘肃优势作物的种植和土壤生态环境的可持续发展。

The province of Gansu is an important agricultural product supplier in China,with Codonopsis pilosula,cauliflower(a typical plateau summer vegetable),potato,and corn(seed crop)being the advantageous crops.To investigate soil pesticide residues of these crops,chromatography and mass spectrometry were employed to analyze the residues of organic pesticides in cropland soil.Additionally,a non-metric multidimensional scale method was used to examine the spatial variations in soil pesticide residues among the different crops.The environmental risks posed by pesticide residues to soil organisms were assessed using the risk-quotient method.The results show that acetochlor,atrazine,and glyphosate were detected in the soil at concentrations of 8.280-52.418,33.693-40.088,and 1.022-18.421μg·kg^(-1),respectively.Thus,the levels of the three herbicides in the soil were found to be relatively low.However,different crop types exhibited variations in the predominant pesticide residues in the analyzed soil samples.Acetochlor was predominantly detected in Codonopsis pilosula planting areas,atrazine was exclusively identified within corn cultivation zones,and glyphosate showed a higher prevalence across the cauliflower,corn,and potato planting regions.In total,thirty-two organophosphate pesticides were detected,with concentrations ranging from 0.369-3845.028μg·kg^(-1).These pesticides were widely detected in Codonopsis pilosula growing areas but were only occasionally detected in cauliflower,corn,and potato growing areas.The risk of most organophosphorus pesticide residues to soil biological environment were within the acceptable range(R Q value≤1).The analysis detected nine pyrethroid pesticides,with deltamethrin being present at a concentration range of 2.904-59.514μg·kg^(-1).These residues were found primarily in the planting soils of potato P2 and cauliflower V3.Compared to the other pyrethroid pesticides,deltamethrin exhibited a higher R Q value;however,the risk remained within an acceptable range based on the results of the soil bioenvironmental risk assessment.Two organochlorine pesticides were also detected;however,the overall concentrations were low,and the soil bioenvironmental risks fell within an acceptable range.The study area contained a diverse range of pesticide residues,however,the overall levels were relatively low.Consequently,the soil bioenvironmental risk remains within acceptable limits,facilitating the sustainable development of advantageous crop cultivation and promoting a healthy soil ecological environment in Gansu.