摘要
以新疆玛纳斯河流域盐渍化弃耕地为对象,研究人为开垦5年后土壤团聚体及其稳定性变化,进而评价开垦对土壤团聚体特性的影响。结果表明：盐碱弃耕地开垦后增加了大团聚体数量;干筛数据表明,开垦前后各土层0.25~0.053 mm粒径团聚体所占比例均最高,占总量的35.50%~47.32%,与其他各粒径差异显著（P〈0.05）;湿筛数据表明,团聚体多在0.053 mm以下,占总量的27.09%~64.50%;干、湿筛数据均表明,开垦后0~5 cm,5~10 cm和10~20 cm土层土壤大于0.25 mm团聚体所占的比例（R0.25）、平均重量直径（MWD）和几何平均直径（GMD）较弃耕地均有显著提高,随着土层深度的增加呈先增加后减小的趋势;弃耕地开垦后各土层土壤的分形维数（D）较开垦前均有所降低,且随着土层深度的增加分形维数（D）值呈先减小后增大的趋势,表明开垦后土壤团粒结构变好,稳定性增强,尤其是在0~20 cm土层表现更为明显。干旱区盐渍化弃耕地人工开垦结合合理的管理措施,有利于土壤大团聚体的增加和土壤结构的稳定。
Understanding soil aggregate stability is crucial for ecological restoration of abandoned fields, especially in arid areas. The objective of this study was to quantify changes in soil aggregation and assess soil aggregate stability after the reclamation of derelict salinized land for five years in the Manas River Valley of Xinjiang. The quantity of large aggregates obtained by dry sieving increased after reclamation. The mass of 0.25- 0.053 mm aggregate accounted for 35.50%- 47.32% of the total soil mass and was significantly greater than that of the other size class aggregates（P〈0.05） after reclamation. Soil mass was mainly distributed in the 0.053 mm size class（27.09%-64.50%）. Data from both dry sieving and wet sieving indicated that the macroaggregate content（R0.25）, mean weight diameter（MWD）, and geometric mean diameter（GMD） in the 0- 5 cm, 5- 10 cm, and 10- 20 cm depths were significantly greater in the reclaimed soil than in the original soil. After reclamation, the fractal dimension（D）decreased as soil depth increased. In contrast, R0.25 exhibited the opposite trend. This indicated that aggregate structure and stability was improved significantly after reclamation, especially in the 0- 20 cm depth. When reasonable management practices were used, reclamation could increase macroaggregation and aggregate stability in the derelict salinized land in arid areas.
出处
《土壤通报》
CAS
CSCD
北大核心
2016年第2期327-333,共7页
Chinese Journal of Soil Science
基金
教育部科学技术研究项目(213039A)
国家自然科学基金(31360320)
国家科技支撑项目(2014BAC14B03)资助
关键词
盐碱弃耕地
开垦
团聚体
分形维数
干旱区
Derelict land caused by salinization
Reclamation
Aggregate
Fractal dimension
