The importance of hydrochar properties for soil application is well known, but the effects of natural aging on hydrochar properties remain ambiguous. The present study aimed to determine the shift patterns in the physicochemical properties of hydrochar through a 16-month soil column aging experiment conducted in a rice-wheat rotation system with hydrochars derived from a wheat straw at 220°C and 260°C. Obvious decreasing hydrophilic/polarity indices and increasing porosity, ash content, and stability occurred in aged hyrdrochar, which were due to the dissolved organic matter (DOM) leaching and the interaction with mineral content and fertilizer during the 16-month aging process. Besides, fewer C-OH, slightly more C=O, and higher aromaticity (C-C/C=C) in aged hydrochar were observed. Meanwhile, the relative abundance of the compounds containing only C, H, and O atoms in water extract of aged hydrochar decreased, while that of the compounds containing C, H, O, and N atoms increased during aging; these findings were attributed to the less labile DOM and microbial degradation and the retention of some plant-derived dissolved organic carbon, respectively. This study provided 16-month aging characterization data regarding alteration in hydrochar physicochemical properties, which was conducive to make a better understanding of the use of hydrochars as sustainable soil amendments from agroecosystems and environmental perspective.

对于土壤应用而言，炭化性质的重要性是众所周知的，但是自然老化对炭化性质的影响仍然不明确。本研究旨在通过在稻麦轮作系统中进行的为期16个月的土壤柱老化试验来确定水炭的理化性质的变化模式，该试验采用在220°C和260°C下由麦秆衍生的水炭进行。在老化的烃中，亲水性/极性指数明显下降，孔隙率，灰分和稳定性增加，这是由于在16个月的老化过程中溶解有机物（DOM）的浸出以及与矿物质含量和肥料的相互作用所致。此外，在老化的水焦中观察到更少的C-OH，稍微更多的C = O和更高的芳香度（CC / C = C）。与此同时，在老化的炭中水提取物中仅含有C，H和O原子的化合物的相对丰度下降，而在老化过程中含有C，H，O和N原子的化合物的相对丰度增加。这些发现分别归因于DOM和微生物降解较不稳定，以及某些植物来源的溶解有机碳的保留。这项研究提供了有关水炭物理化学性质变化的16个月老化表征数据，这有助于从农业生态系统和环境角度更好地了解水炭作为可持续土壤改良剂的用途。这些发现分别归因于DOM和微生物降解较不稳定，以及某些植物来源的溶解有机碳的保留。这项研究提供了有关水炭物理化学性质变化的16个月老化表征数据，这有助于从农业生态系统和环境角度更好地了解水炭作为可持续土壤改良剂的用途。这些发现分别归因于DOM和微生物降解较不稳定，以及某些植物来源的溶解有机碳的保留。这项研究提供了有关水炭物理化学性质变化的16个月老化表征数据，这有助于从农业生态系统和环境角度更好地了解水炭作为可持续土壤改良剂的用途。