| 长期施肥对旱塬麦田土壤大团聚体有机碳组分及冬小麦产量的影响 |
| 摘要点击 2605 全文点击 485 投稿时间：2023-08-05 修订日期：2023-10-09 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 黄土旱塬 麦田土壤 长期施肥 有机碳组分 作物产量 |
| 英文关键词 loess plateau wheat field long-term fertilization organic carbon components crop yield |
| DOI 10.13227/j.hjkx.20240741 |
|
| 中文摘要 |
| 大团聚体是土壤有机碳固存的主要场所,对土壤肥力提升具有重要意义. 为揭示长期不同施肥措施下大团聚体有机碳的固持机制及产量效应,依托8 a定位试验,设不施肥（CK）、农户施肥（NP）、测控施肥（NPK）、测控+有机肥配施（NPKM）以及测控+生物有机肥配施（NPKB）这5个处理,采用“团聚体-密度”联合分组法,分析了黄土旱塬麦田土壤大团聚体中粗颗粒有机碳（cPOC）、细颗粒有机碳（fPOC）、微团聚体颗粒有机碳（iPOC）、游离态粉+黏颗粒有机碳（s+c_f）和微团聚体粉+黏颗粒有机碳（s+c_m）的变化特征及其与土壤碳投入和产量形成之间的关系. 结果表明,长期有机无机配施（NPKM和NPKB）较单施化肥（NP和NPK）显著提高了大团聚体中有机碳（SOC）含量,提升幅度高于对应处理土壤SOC提升幅度. 长期施肥有提高大团聚中cPOC、fPOC和iPOC含量,降低s+c_f和s+c_m含量趋势,且长期有机无机配施显著提高了大团聚中cPOC、fPOC和iPOC储量占比,显著降低了s+c_f储量占比,而长期单施化肥仅显著提升了大团聚中cPOC储量占比. 相关分析表明,小麦籽粒产量与有机碳组分（cPOC和iPOC）含量、土壤总有机碳含量、 >0.25 mm大团聚体有机碳含量以及土壤有机碳投入量存在极显著正相关性,相关系数为0.645~0.883. 综合来看,黄土旱塬麦区长期施肥尤其是有机无机配施,通过增加土壤碳投入量促进了游离态粉+黏颗粒有机碳（s+c_f）向其它形态有机碳的转化,进而整体提升大团聚体有机碳含量,为作物增产创造了良好土壤环境. |
| 英文摘要 |
| Soil macro-aggregates are the main location for soil organic carbon （SOC） sequestration, which is of great significance to improve soil fertility. This study aimed to understand the mechanisms of the organic carbon （OC） sequestration in macroaggregates and improve crop yield in wheat fields on the loess plateau. With the aggregate-density fractionation method, an eight-year experiment was conducted to investigate the following three factors： ① the effects of long-term fertilization on OC fractions within macroaggregates； ② the variation characteristics of OC fractions within macroaggregates, including coarse particulate organic carbon （cPOC）, fine particulate organic carbon （fPOC）, intra-microaggregate particulate organic carbon （iPOC）, free silt and clay particulate carbon （s+c_f）, and intra-microaggregate silt and clay particulate carbon （s+c_m）； ③ and the relationships between them and SOC input and yield formation. The treatments included no fertilization （CK）, farmer pattern （NP）, optimized fertilizers pattern （NPK）, optimized fertilizers + organic fertilizers pattern （NPKM）, and optimized fertilizers + biological organic fertilizers pattern （NPKB）. The results showed that the application of organic and chemical fertilizer （NPKM and NPKB） improved significantly the SOC content in macroaggregates compared with that in the single fertilizer treatment （NP and NPK）, which had a greater increase in SOC content in macroaggregates than that of the soil. All fertilization treatments had a tendency to increase the content of fractions iPOC, fPOC, and iPOC in macroaggregates, but silt and clay carbon （s+c_f and s+c_m） contents were decreased. The application of manure combined with chemicals markedly increased the allocations of fractions cPOC, fPOC, and iPOC reserves, but it greatly decreased （s+c_f） reserves allocation. However, the application of chemical fertilizers only significantly increased the proportion of cPOC reserves in macroaggregates. Correlation analysis showed that there were significant positive correlations among wheat grain yield and OC fractions （cPOC and fPOC） contents, SOC content, the OC content of >0.25 mm macroaggregates, and SOC input, and the correlation coefficient was 0.645-0.883. In conclusion, long-term fertilization, especially combined with organic fertilizer, could promote the free silt and clay carbon fraction （s+c_f） to transfer into other forms of OC components through the increase in soil carbon input in the wheat field of the loess plateau. Furthermore, the OC content of macroaggregates was increased overall, providing a good soil environment for crop yield. |
|
|
|
