不同调控模式下寒区土壤物理结构与水力特性改良研究  

Improvement of Soil Physical Structure and Hydraulic Characteristicsin Cold Regions by Different Regulation Modes

作　　者：付强 石净[1] 李天霄 侯仁杰 FU Qiang;SHI Jing;LI Tianxiao;HOU Renjie(School of Water Conservancy and Civil Engineering,Northeast Agricultural University,Harbin 150030,China;Key Laboratory for High Effective Utilization of Agricultural Water Resources,Ministry of Agriculture and Rural Affairs,Northeast Agricultural University,Harbin 150030,China)

机构地区：[1]东北农业大学水利与土木工程学院,哈尔滨150030 [2]东北农业大学农业农村部农业水资源有效利用重点实验室,哈尔滨150030

出　　处：《农业机械学报》2023年第9期374-385,共12页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金区域联合基金项目(U20A20318);国家自然科学基金面上项目(51279033、52279035);国家杰出青年科学基金项目(51825901)。

摘　　要：为探究季节性冻土区冻结前后施加生物炭和秸秆对农田土壤的改良效果,选取黑土作为研究对象,基于田间试验,设置4种不同调控措施(BL:空白对照;CLS:施用生物炭;JLS:施用秸秆;CJLS:联合施用),分析土壤团聚体稳定性、孔径分布特征、土壤水分特征曲线、土壤累计入渗量、饱和导水率K_(sat)的变化,在此基础上,探究土壤持水性、导水性等土壤物理特性变异特征。结果表明,施用生物炭和秸秆有效抑制冻融循环作用对土壤结构的不利影响,有效保持土壤团聚体稳定性。施加外源生物质材料改善土壤孔隙分布,在冻结前期增加中间段孔径(0.3~100μm)比例,在外源生物质材料和冻融交替作用双重影响下,增加中间段孔径比例19.05%~35.04%,增加土壤空隙(>100μm)比例4.33%~16.22%,降低极微孔径(0~0.3μm)比例9.09%~18.18%,其中CJLS处理表现最优。在冻结前期,施用生物炭和秸秆增加张力-5 cm条件下60 min的土壤累计入渗量73.68%、60.52%、151.10%,而在融化期,受外源生物质材料冻融老化影响,其发挥的积极效应有所减弱,土壤累计入渗量最高仅增加112.28%。同时,施加生物炭和秸秆提高冻融前后的土壤饱和含水率,增强土壤持水能力,这有助于提高春季土壤抗干旱能力。在外源生物质材料和冻融循环双重作用下植物可用含水率增加,同时冻融前后K_(sat)均增加,但融化期CLS和JLS处理与BL的差异逐渐减缓。研究结果对于合理施用生物炭和秸秆资源、揭示改良土壤物理特性响应机制具有重要意义。To investigate the effect of applying biochar and straw on the improvement of agricultural soils before and after freezing in seasonal permafrost areas,black soil was selected as the research object,and four different regulation measures(BL:blank control;CLS:application of biochar;JLS:application of straw;CJLS:combined application)were set up based on field experiments to analyze the stability of soil aggregates,pore size distribution characteristics and soil moisture characteristic curves.The results showed that the variation of soil physical properties such as soil water holding capacity and hydraulic conductivity was investigated based on the variation of soil infiltration and saturated hydraulic conductivity(Ksat).The results showed that the application of biochar and straw effectively suppressed the adverse effects of freeze-thaw cycles on soil structure,and effectively maintained the stability of soil aggregates.The application of exogenous biomass materials improved soil pore distribution,increased the proportion of intermediate pore size(0.3~100μm)in the early freezing period,increased the proportion of intermediate pore size 19.05%~35.04%,increased the proportion of soil voids(greater than 100μm)by 4.33%~16.22%,and decreased the proportion of very small pore size(0~0.3μm)by 9.09%~18.18%under the combined effect of exogenous biomass materials and freeze-thaw alternation,and with the CJLS treatment performing the best.In the pre-freezing period,the application of biochar and straw increased the cumulative soil infiltration at 60 min under tension-5 cm by 73.68%,60.52%and 151.10%,while in the thawing period,the positive effect exerted by freeze-thaw aging of exogenous biomass materials was diminished,and the cumulative soil infiltration was increased by a maximum of 112.28%only.Meanwhile,the application of biochar and straw increased the saturated soil water content before and after freeze-thaw and enhanced the soil water holding capacity,which contributed to the improvement of soil drought resistance in

关 键 词：生物炭 秸秆 持水性 导水性 土壤结构 

分 类 号：S156[农业科学—土壤学] S157[农业科学—农业基础科学]