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已知硝化抑制剂氯甲基吡啶能有效抑制土壤硝化,减少氮的淋洗和硝化-反硝化损失,促进作物对氮素的吸收,但是其对干旱区滴灌条件下土壤微生物群落功能多样性的影响尚不明确。本试验研究了尿素添加氯甲基吡啶(Nitrapyrin)分次随水滴施对干旱区滴灌棉田土壤微生物碳代谢和群落功能多样性的影响。试验采用随机区组设计,设置不施氮肥[CK,0 kg(N)·hm~(-2)]、单施尿素[Urea,225 kg(N)·hm~(-2)]和尿素添加氯甲基吡啶[Urea+nitrapyrin,225 kg(N)·hm~(-2)+2.25 kg(nitrapyrin)·hm~(-2)]3个处理,重复4次,采用Biolog-ECO法进行土壤微生物碳代谢和功能多样性研究。结果表明:与不施氮肥(CK)相比,施用尿素和尿素添加氯甲基吡啶均能显著提高土壤微生物对31种碳源的代谢能力(AWCD)和代谢强度(S)(P<0.05),增加土壤微生物多样性和丰富度(Shannon指数、Simpson指数、Mc Intosh指数和Richness指数)以及对各类碳源的利用能力。尿素添加氯甲基吡啶随水滴施后,土壤微生物AWCD值、碳代谢强度、Shannon指数、Simpson指数、Mc Intosh指数以及Richness指数均大于单施尿素处理,且较单施尿素处理分别提高13.83%、9.33%、1.29%、1.34%、11.26%、11.79%(P>0.05),均匀度指数则低于单施尿素处理(P>0.05)。PCA和聚类分析结果表明,施用尿素和尿素添加氯甲基吡啶对土壤微生物群落功能多样性均产生了显著影响,但尿素添加氯甲基吡啶与单施尿素处理差异不显著;氯甲基吡啶的添加提高了土壤微生物对聚合物、酚酸、羧酸、氨基酸以及胺类的利用,降低了对碳水化合物的利用(P>0.05)。上述研究结果得出,在干旱区滴灌棉田,尿素添加氯甲基吡啶分次随水滴施可调控土壤的微生态环境,在一定程度上提高土壤微生物的代谢能力,增加微生物群落功能多样性,缓解因长期施用无机氮肥导致的土壤微生物活性的降低。
Known nitrification inhibitor chloromethyl pyridine can effectively inhibit soil nitrification, reduce nitrogen leaching and nitrification - denitrification losses, and promote crop nitrogen uptake, but its drip irrigation in arid zone microbial community diversity The impact is not clear. This study investigated the effects of urea supplementation with chlorpyrifos on soil microbial carbon metabolism and community functional diversity in drip irrigation cotton fields in arid zones. A randomized block design was adopted in the experiment. Nitrogen (CK, 0 kg N / hm -2) and urea Urea (225 kg N / hm -2) Three treatments of Urea + nitrapyrin (225 kg N · hm -2 +2.25 kg nitrapyrin · hm -2) were repeated four times and the soil was treated with Biolog-ECO method Microbial carbon metabolism and functional diversity. The results showed that addition of chloromethylpyridine to both urea and urea could significantly increase the metabolic capacity (AWCD) and metabolic intensity (S) of soil carbon sources to 31 carbon sources (P <0.05) compared with no nitrogen application (CK) , Increased soil microbial diversity and abundance (Shannon index, Simpson index, Mc Intosh index and Richness index) as well as their ability to utilize various types of carbon sources. Compared with urea application, the AWCD value, carbon metabolism intensity, Shannon’s index, Simpson index, Mc Intosh index and Richness index of soil microbial biomass after adding chloromethylpyridine to urea were higher than those under urea application, and increased by 13.83% 9.33%, 1.29%, 1.34%, 11.26% and 11.79% respectively (P> 0.05). The evenness index was lower than that of single urea treatment (P> 0.05). The results of PCA and cluster analysis showed that the addition of chloromethylpyridine to urea and urea had a significant effect on the functional diversity of soil microbial communities, but there was no significant difference between the addition of chloromethylpyridine and urea alone. Chloromethylpyridine Increased soil microbial use of polymers, phenolic acids, carboxylic acids, amino acids and amines, and reduced carbohydrate utilization (P> 0.05). The results of the above study showed that in the arid zone drip irrigation cotton fields, the addition of urea picoline can improve the microbial metabolism ability, increase the functional diversity of microbial communities and alleviate Soil microbial activity decreased due to long-term application of inorganic nitrogen fertilizer.