College of Natural Resources and Environment, Joint Institute for Environmental Research and Education, South China Agricultural University, Guangzhou 510642, China.
College of Tropical Crops, Hainan University, Haikou 570228, China.
Ecotoxicol Environ Saf. 2023 Sep 15;263:115387. doi: 10.1016/j.ecoenv.2023.115387. Epub 2023 Aug 18.
Acidic soils cover approximately 50 % of the arable land with high NO emission potential. 3,4-dimethylpyrazole phosphate (DMPP) inhibits NO emission from soils; however, its efficiency is affected by acidity. Liming is used for soil conditioning to ameliorate the effects of acidity. In the present study, we investigated the effects of liming on the efficiency of DMPP in inhibiting NO emission in acidic soils and the mechanisms involved. We evaluated the impact of liming, DMPP, and combined application and its microbial responses in two acidic soils from Zengcheng (ZC) and Shaoguan (SG) City, Guangdong Province, China. Soils were subjected to four treatments: un-limed soil (low soil pH) + urea (LU), un-limed soil + urea + DMPP (LD), limed soil (high soil pH) + urea (HU), and limed soil + urea + DMPP (HD) for analyses of the mineral N, NO emissions, and full-length 16S and metagenome sequencing. The results revealed that, HU significantly decreased and increased the NO emission by 17.8 % and 235.0 % in ZC and SG, respectively, compared with LU. This was caused by a trade-off between NO production and consumption after liming, where microbial communities and N-cycling functional genes show various compositions in different acidic soils. LD reduced NO emission by 23.5 % in ZC, whereas decreased 1.5 % was observed in SG. Interestingly, DMPP efficiency considerably improved after liming in two acidic soils. Compared with LU, HD significantly reduced NO emissions by 61.2 % and 48.5 % in ZC and SG, respectively. Synergy of mitigation efficiency was observed by lime and DMPP application, which was attributed to the changes in the dominant nitrifiers and the increase in NO consumption by denitrifiers. The combined application of lime and DMPP is a high-efficiency strategy for NO mitigation can ensure agricultural sustainability in acidic arable soils with minimal environmental damage.
酸性土壤约占可耕地的 50%，具有较高的 NO 排放潜力。3,4-二甲基吡唑磷酸盐（DMPP）可抑制土壤中的 NO 排放；然而，其效率受酸度影响。石灰用于土壤调理以改善酸度的影响。在本研究中，我们研究了石灰对酸性土壤中 DMPP 抑制 NO 排放效率的影响及其相关机制。我们评估了石灰、DMPP 和联合应用及其在来自中国广东省增城市（ZC）和韶关市（SG）的两种酸性土壤中的微生物响应的影响。土壤采用四种处理方式：未施石灰的土壤（低土壤 pH）+尿素（LU）、未施石灰的土壤+尿素+DMPP（LD）、施石灰的土壤（高土壤 pH）+尿素（HU）和施石灰的土壤+尿素+DMPP（HD）进行分析，以分析矿质氮、NO 排放以及全长 16S 和宏基因组测序。结果表明，与 LU 相比，HU 分别使 ZC 和 SG 的 NO 排放降低了 17.8%和 235.0%，这是石灰施用后 NO 产生和消耗之间的权衡所致，其中微生物群落和 N 循环功能基因在不同的酸性土壤中表现出不同的组成。LD 在 ZC 中使 NO 排放减少了 23.5%，而在 SG 中则减少了 1.5%。有趣的是，石灰施用后 DMPP 的效率在两种酸性土壤中均显著提高。与 LU 相比，HD 分别使 ZC 和 SG 的 NO 排放显著减少了 61.2%和 48.5%。石灰和 DMPP 的联合应用具有协同增效作用，这归因于优势硝化菌的变化和反硝化菌对 NO 消耗的增加。石灰和 DMPP 的联合应用是一种高效的 NO 减排策略，可以确保在酸性可耕地中实现农业可持续性，同时最大限度地减少环境破坏。
