绿肥施用对复垦果园土壤水分特性的影响

Effects of Green Manure Application on Soil Moisture Characteristics in Reclaimed Orchards

摘要: 目的：复垦土地重新建植果园面临着土壤砾石含量高、肥力不足等问题。研究绿肥种植对整治后土壤水分特性的改良效果，可以为关中地区整治后果园土壤水分高效管理和地力提升提供理论依据与技术支撑。方法：以杨陵塿土为试验对象，砾石含量分4个水平：5%，10%，20%和30%。设置3种绿肥处理：清耕对照(CK)、毛叶苕子种植(HV)、黑麦草种植(RG)，采用随机区组设计，3次重复。测定容重、孔隙度、饱和导水率、水分特征曲线、田间持水量、饱和含水量等指标，通过统计分析明确不同处理间的差异及绿肥改良机制。结果：砾石含量的增加使得土壤容重升高，总孔隙度增加，土壤的饱和导水率增加，但是田间持水量和饱和含水量降低。与CK相比，HV处理和RG处理均能显著改善土壤物理性状及水分特性。两种绿肥相比，毛叶苕子对土壤结构及水分特性的综合改良效果显著优于黑麦草。结论：砾石含量的增加对杨陵塿土的土壤水分特性具有一定的影响。毛叶苕子、黑麦草均可有效修复整治后土壤水分特性，其中毛叶苕子改良效果更优，可作为杨陵区及同类区域整治后苹果园的优先绿肥品种，配合盛花期翻压还田，实现土壤水分高效利用与果园可持续生产。

Abstract: Objective: Reclaimed land used for orchard replanting faces problems such as high soil gravel content and insufficient fertility. Studying the effect of green manure planting on improving soil moisture characteristics after reclamation can provide theoretical basis and technical support for efficient soil moisture management and soil fertility improvement in orchards after reclamation in the Guanzhong Plain. Methods: Yangling soil was used as the experimental subject, with gravel content divided into four levels: 5%, 10%, 20%, and 30%. Three green manure treatments were set up: clean cultivation control (CK), hairy vetch planting (HV), and ryegrass planting (RG), using a randomized block design with three replicates. Bulk density, porosity, saturated hydraulic conductivity, water characteristic curve, field capacity, and saturated water content were measured. Statistical analysis was used to clarify the differences between different treatments and the green manure improvement mechanism. Results: Increased gravel content led to higher soil bulk density, increased total porosity, and increased saturated hydraulic conductivity, but decreased field capacity and saturated water content. Compared with the control (CK), both the HV and RG treatments significantly improved soil physical properties and water characteristics. Among the two green manures, hairy vetch showed a significantly better overall improvement effect on soil structure and water characteristics than ryegrass. Conclusion: Increased gravel content has a certain impact on the soil water characteristics of Yangling hilly soil. Both hairy vetch and ryegrass can effectively repair the soil water characteristics after remediation, with hairy vetch showing a better improvement effect. It can be used as a priority green manure variety for apple orchards in Yangling District and similar areas after remediation, combined with plowing and incorporating into the field during the peak flowering period to achieve efficient soil water utilization and sustainable orchard production.