[目的]覆盖作物通过连续的地表覆盖和丰富的地下根系在土壤生态环境中发挥积极作用，探明不同根系特征覆盖作物对土壤渗透性能的影响，可为基于覆盖作物提升黑土农田生态系统服务功能相关研究提供理论依据。[方法]以冬季休耕地(裸地)为对照，以种植冬小麦(Triticum aestivum L。)、紫花苜蓿(Medicago sativa L。)、毛叶苕子(Vicia villosa Roth。)耕地为研究对象，使用双环刀法和Win-RHIZO Pro LA2004分析系统，研究不同冬季覆盖作物对农田黑土表层土壤渗透性能和根系特征的影响。[结果]①种植冬季覆盖作物可不同程度降低土壤容重，增加土壤含水率，促进有机质积累。②冬季覆盖作物土壤渗透参数与无冬季作物覆盖相比无显著差异，但随着渗透时间的延长，渗透过程整体表现出更稳定更集中的趋势。③初始渗透速率、稳定渗透速率和平均渗透速率均与土壤容重和孔隙度有显著相关关系，根系生物量通过影响土壤非毛管孔隙度、非毛管/毛管孔隙比进而影响土壤渗透性能。[结论]东北黑土区种植冬季覆盖作物短期内(仅经历一季冻融循环)虽未显著增加土壤渗透速率和渗水量，但可通过积累地下根系生物量、改善土壤物理结构呈现出积极影响土壤水分入渗的潜力，其中须根系(冬小麦)冬季覆盖作物调节入渗能力的优势相对明显。本研究结果可为东北黑土区冬季覆盖作物种植技术研究、推广提供参考。
Effect of Winter Cover Crops on the Infiltration Properties of Top Layer of Black Soil
[Objective]Cover crops play an active role in the soil ecosystem by providing continuous surface cover and abundant underground root system.Clarifying the effect of cover crops on soil infiltration performance can provide a theoretical basis for research on enhancing the ecosystem service function of black soil farmland through cover crops.[Method]Taking the winter fallow land(bare land)as a control,based on the double-cutting ring method and Win-RHIZO Pro LA2004 analysis system,the soil infiltration performance and root characteristics of the surface layer of winter wheat(Triticum aestivum L.),alfalfa(Medicago sativa L.)and Hair Vetch(Vicia villosa Roth.)were compared by one-way ANOVA,stepwise regression and path analysis.[Result]① Winter cover crops could decrease soil bulk density and increase soil moisture content and organic matter content to some degree.② There was no significant difference of infiltration between winter cover crops and CK,but the trend was more stable and more clustered with the increase of infiltration time.③ The initial infiltration rate,stabilized infiltration rate and average infiltration rate were significantly correlated with soil bulk density and porosity,and the root biomass affected soil infiltration performance by affecting soil non-capillary porosity and non-capillary/capillary porosity ratio.[Conclusion]Although planting winter cover crops in the black soil region of Northeast China did not significantly increase the soil infiltration performance in the short term,it showed the potential to positively affect soil water infiltration by accumulating underground root biomass and improving the physical structure,of which the overwintering advantage of winter wheat with fibrous root system is more obvious,and the results of the study can provide a reference for the basic research on winter cover crops in the black soil region and the technical promotion research.
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