Under cold climate conditions, the temporal and spatial distribution of heat and the influencing factors in different layers of Albic soil remain unclear. Here, we aimed to clarify the influence of biochar on soil heat storage capacity and identify approaches to regulate temporal-spatial variations in Albic soil temperature. To this end, we studied thermal properties and temporal-spatial temperature variations in different soil layers (10 and 20 cm) amended with biochar at different concentrations (0, 10, 20, 30, 40 g·kg^-1) in the key growth stages of soybeans through pot experiments for two years. We found that the daily mean soil temperature and accumulated soil temperature improved during the 2 years in both soil layers after biochar application. Compared with the control, the biochar treatments increased soil daily minimum temperature, decreased soil daily maximum temperature and soil temperature fluctuations, postponed the soil heating stage by 1 h, and caused a "warming effect" during the soil cooling stage. Furthermore, biochar treatment enhanced the thermal capacity of the Albic soil by 7.49% and 6.53% compared with the control in 2016 and 2017, respectively, whereas thermal conductivity and thermal diffusivity were decreased compared with the control. Biochar regulated the temporal-spatial response variation in temperature of the Albic soil as follows: biochar distributed heat in the Albic soil more uniformly over time by changing the soil temperature cycle and reducing the temperature difference, and heat tended to move downwards into the soil layers by increasing the heat capacity and reducing soil thermal conductivity and thermal diffusivity. Biochar changed the heat storage capacity of the Albic soil and temporal-spatial distribution of heat. These changes provide sufficient, timely, and effective heat supply for crop growth. Furthermore, biochar treatments had a significant and positive effect on soil physical properties and crop yield. In cold areas, these changes would help crops resist temperature changes caused by extreme weather and reduce the rate of cold damage. The results of this study have important practical relevance for enriching the basic scientific theory of biochar application.

在寒冷的气候条件下，白垩纪土壤不同层中热量的时空分布和影响因素仍不清楚。在这里，我们旨在阐明生物炭对土壤储热能力的影响，并确定调节Albic土壤温度时空变化的方法。为此，我们研究了用不同浓度（0、10、20、30、40 g·kg ^-1的生物炭）修正的不同土壤层（10和20 cm）的热性质和时空温度变化。），通过两年的盆栽试验，处于大豆的关键生长阶段。我们发现，在施用生物炭后的两个土层中，这两年的日平均土壤温度和累积土壤温度都有所提高。与对照相比，生物炭处理提高了土壤日最低温度，降低了土壤日最高温度和土壤温度波动，将土壤加热阶段推迟了1小时，并在土壤冷却阶段产生了“变暖效应”。此外，生物炭处理与2016年和2017年相比，分别提高了Albic土壤的热容7.49％和6.53％，而热导率和热扩散率与对照相比降低了。生物炭调节白化土壤温度的时空响应变化如下：生物炭通过改变土壤温度循环并减小温度差，使热量在白化土壤中随时间分布更均匀，并且热量倾向于向下移动到土壤层中通过增加热容并减少土壤的热导率和热扩散率。生物炭改变了白化土壤的储热能力和热量的时空分布。这些变化为作物生长提供了充足，及时和有效的热量供应。此外，生物炭处理对土壤物理性质和农作物产量具有显着的积极影响。在寒冷地区，这些变化将帮助农作物抵御极端天气导致的温度变化，并降低冷害率。