Department of Soil and Agricultural Engineering, Laval University, Quebec City, QC, Canada.
Institut Agro-INRA, UMR 1069, Sol Agro et hydrosystéme Spatialisation, 35000, Rennes, France.
Sci Rep. 2021 Mar 24;11(1):6733. doi: 10.1038/s41598-021-86106-4.
Soil organic carbon (SOC) has a significant effect on the carbon cycle, playing a vital role in environmental services and crop production. Increasing SOC stock is identified as an effective way to improve carbon dioxide sequestration, soil health, and plant productivity. Knowing soil water is one of the primary SOC decomposition driver, periods in the crops growth stages with increased water movement might influence the SOC dynamics. Here, we evaluate the temporal effect of four precision irrigation thresholds ([Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] kPa) in potato crop on SOC dynamics using the Partial Least Square algorithm and the Tea Bag Index in a sandy soil under potato production. The difference of SOC decomposition rate between the precision irrigation thresholds is developed in the second quarter of the growing season, between 38 and 53 days after planting. This critical period occurred in a stage of strong vegetative growth and rapid irrigation cycles. The precision irrigation threshold affected the decomposition rate of SOC. A faster decomposition of labile organic carbon was promoted by water excess ([Formula: see text] kPa). The dryer ([Formula: see text], [Formula: see text], and [Formula: see text] kPa) precision irrigation thresholds did not show any differences. The advancement of this knowledge may promote soil health conservation and carbon sequestration in agricultural soil.
土壤有机碳（SOC）对碳循环有重大影响，在环境服务和作物生产中起着至关重要的作用。增加 SOC 储量被认为是提高二氧化碳固存、土壤健康和植物生产力的有效途径。了解土壤水分是 SOC 分解的主要驱动因素之一，在作物生长阶段水分增加的时期可能会影响 SOC 动态。在这里，我们使用偏最小二乘算法和茶包指数，在马铃薯生产下的沙质土壤中，评估了马铃薯作物中四个精准灌溉阈值 ([Formula: see text]、[Formula: see text]、[Formula: see text] 和 [Formula: see text] kPa) 对 SOC 动态的时间效应。在种植后 38 到 53 天的生长季节的第二个季度，不同的精准灌溉阈值之间的 SOC 分解速率存在差异。这个关键时期发生在强烈的营养生长和快速灌溉周期阶段。精准灌溉阈值影响 SOC 的分解速率。过量的水([Formula: see text] kPa)促进了易分解有机碳的快速分解。较干燥的（[Formula: see text]、[Formula: see text] 和 [Formula: see text] kPa）精准灌溉阈值没有显示出任何差异。这一知识的进步可能会促进农业土壤的土壤健康保护和碳固存。
