【作者】 张燕；

【导师】 毕江涛； 马建华；

【作者基本信息】 宁夏大学 ， 农业硕士（专业学位）， 2024， 硕士

【摘要】 随着新烟碱类农药杀虫剂在国际上的频繁使用,吡虫啉等这类杀虫剂引发的生态环境问题日益突出。吡虫啉是一种硝基亚甲基类内吸杀虫剂,其对病虫害的防治表现出良好的治疗性。因此,吡虫啉在农业领域有着广泛的应用。新烟碱类农药已对土壤环境造成了潜在危害,添加生物炭是一种阻控该类农药在土壤中流动,并降低其生态风险的有效方法,因此研究生物炭对土壤中新烟碱类农药环境行为的影响具有重要的现实意义。基于此,本论文利用高效液相色谱方法定量分析了生物炭添加后吡虫啉分别在番茄植株中和土壤环境中的降解行为以及土壤微生物群落的变化。进而分析现阶段研究中的不足,对未来的研究方向进行展望,可为土壤中生物炭调控技术的发展提供参考。1、通过吡虫啉在番茄植株上快速简便的残留分析方法,符合农药残留分析的要求。以推荐使用的有效成分为44.98-59.97 a.i./hm2施药剂量下,吡虫啉在番茄植株不同部位及其种植土壤中的沉积浓度均随着时间的增加而呈现降解趋势。在灌根施药方式下,吡虫啉主要沉积在番茄种植.土壤中以及叶片部位中。番茄植株不同部位及种植土壤中沉积浓度为叶片>种植土壤>根>茎>果实。吡虫啉在番茄植株不同部位的消解呈现先快后慢的趋势。其中根的半衰期5.50 d,果实的半衰期6.24 d,茎的为8.45 d,土壤10.19 d,叶19.80 d。在初始沉积量(2h的残留量)中,土壤最高为4.51 mg/kg,其次是根为 1.51 mg/kg。2、本文研究了生物炭添加在土壤中,吡虫啉在番茄植株以及种植土壤中的残留量。结果表明在添加生物炭后番茄植株中吡虫啉残留量均比CK低,混合生物炭的土壤样品中吡虫啉残留量均比CK高,说明生物炭添加后可以有效降低番茄植株中吡虫啉的残留量。并研究不同百分含量的生物炭对番茄植株及种植土壤吡虫啉残留的影响,结果显示,在植株地上部分,CK的半衰期为8.35d,S1(1%生物炭)、S10(10%生物炭)、S20(20%生物炭)均缩短了半衰期分别为为6.48 d、8.05 d、4.41 d,而S5(5%生物炭)延长了半衰期为11.18 d。番茄植株地下部分,CK半衰期为7.62 d,S10缩短了半衰期为6.66 d,S1、S5、S20均延长了半衰期。在施药土壤中,CK半衰期为9.63 d,S20缩短了半衰期至4.95 d,其他处理均延长了半衰期。本试验结果表明20%生物炭处理为最佳结果。3、施用生物炭与CK相比,土壤中的细菌、真菌Alpha多样性指数表高于CK,20%生物炭的处理可以增加细菌中鞘氨醇菌属(Sphingobium)、德沃斯氏菌属(Devosia)、交替红杆菌(Altererythrobacter)。增加真菌中 Ascomycota_gen_Incertae_sedis、Fungi_gen_Incertae_sedis、Helotiales_gen_Incertae_sedis、Acrostalagmus_gen_Incertae_sedis。结果表明,添加生物炭对微生物群落的结构组成以及群落丰富度有改变。综上所述,在土壤中添加20%生物炭后,削弱了吡虫啉在番茄植株体内的残留,显著增加了吡虫啉在生物炭中的残留。同时,生物炭加入土壤中可以提高土壤细菌、真菌群落积极而显著的变化,这为我们通过施用生物炭,提高土壤微生物种群数量、减少化学农药施用、修复污染土壤、降低大气环境污染、对土壤环境及植株农药合理施用的农业措施提供了理论基础。更多还原

【Abstract】 With the frequent use of neonicotinoid insecticides in the world,the ecological and environmental problems caused by imidacloprid and other insecticides have become increasingly prominent.Imidacloprid is a nitromethylene systemic insecticide,which shows good therapeutic effect on pest control.Therefore,imidacloprid is widely used in agriculture.Neonicotinoid pesticides have caused potential harm to the soil environment.Adding biochar is an effective method to control the flow of these pesticides in soil and reduce their ecological risks.Therefore,it is of great practical significance to study the impact of biochar on the environmental behavior of neonicotinoid pesticides in soil.Based on this,the degradation behavior of imidacloprid in tomato plants and soil environment and the changes of microbial community in tomato plants and soil after biochar addition were quantitatively analyzed by high performance liquid chromatography.Furthermore,the shortcomings in the current research are analyzed and the future research direction is prospected,which can provide reference for the development of biochar regulation technology in soil.1.The rapid and simple residue analysis method of imidacloprid on tom ato plants meets the requirements of pesticide residue analysis.At the recommended dosage of 44.98-59.97 the initial deposition concentration of imidacloprid in different parts of tomato plant and its planting soil showed a degradation trend with the increase of time.Imidacloprid is mainly deposited in tomato planting soil and leaves under the mode of root irrigation.The sediment concentration in different parts of tomato plant and planting soil is leaf>planting soil>root>stem>fruit.The degradation of imidacloprid in different parts of tomato plants showed a trend of fast at first and then slow.Among them,the half-life of roots is 5.50 d,that of fruits is 6.24 d,that of stems is 8.45 d,that of soil is 10.19 d,and that of leaves is 19.80 d.In the initial deposition amount(2 h residue),the highest is 4.51 mg/kg in soil,followed by 1.51 mg/kg in roots.2.This paper studied the residue of imidacloprid in tomato plants and planting soil when biochar was added to soil.The results showed that the residue of imidacloprid in tomato plants was lower than CK after adding biochar,and the residue of imidacloprid in soil samples mixed with biochar was higher than CK,which indicated that the residue of imidacloprid in plants could be effectively reduced after adding biochar.The effects of different percentage of biochar on imidacloprid residues in tomato plants and planting soil were also studied.The results showed that the half-life of CK was 8.35 d,and the half-lives of S1(1%biochar),S10(10%biochar)and S20(20%biochar)were shortened by 11.18 d,8.05 d and 4.41 d respectively,while S5.In the underground part of tomato plant,the half-life of CK was 7.62 d,that of S10 was shortened to 6.66 d,and that of S1,S5 and S20 was prolonged.In the applied soil,the half-life of CK was slightly 9.63 d,and that of S20 was shortened to 4.95d,while that of other treatments was prolonged.The experimental results show that 20%biochar treatment is the best result.3.Compared with CK,the Alpha diversity index of bacteria and fungi in the soil is higher than CK,and the treatment of 20%biochar can increase Sphingobium,Devosia and Alternaria.Increase fungi Ascomycota_gen_Incertae_sedis,Fungi_gen_Incertae_sedis,Helotiales_gen Incertae_sedis,Acrostalagmus_gen_incertae_sedis.The results showed that adding biochar changed the structure and richness of microbial community.To sum up,after adding 20%biochar to the soil,the residue of imidacloprid in tomato plants was weakened and the residue of imidacloprid in biochar was significantly increased.At the same time,it can improve the positive and significant changes of soil bacterial and fungal communities,which provides a theoretical basis for our agricultural measures to increase the number of soil microbial populations,reduce the application of chemical pesticides,and rationally apply pesticides to soil environment and plants by applying biochar.更多还原