恢复年限对裸露边坡土壤团聚体颗粒和碳、氮、磷分布的影响  

Influence of Recovery Time on the Distribution Characteristics of Soil Aggregates and the Contents of Carbon,Nitrogen and Phosphorus on Bare Slopes

作　　者：冯春晓[1] 艾应伟[1] 王克秀[1] 郭雪姣[1] 肖敬尧[1] 

机构地区：[1]四川大学生命科学学院,生物资源与生态环境教育部重点实验室,成都610064

出　　处：《水土保持学报》2015年第5期156-161,共6页Journal of Soil and Water Conservation

基　　金：国家自然科学基金项目(41171175)

摘　　要：研究了不同恢复年限下裸露边坡土壤团聚体颗粒的分布以及土壤团聚体颗粒碳、氮、磷元素的含量。研究选取切挖后恢复43a和切挖后恢复3a的裸露边坡为研究对象,以农田为对照,分别采集上述边坡土壤样本,通过一组土壤筛将土壤样品筛分,计算各粒级（〈0.25mm,0.25~0.5mm,0.5~1mm,1~2mm,2~3mm,3~5mm和〉5mm共7个粒级）土壤团聚体百分含量,而后将土壤各粒级团聚体分别研磨用于化学测定。研究结果表明,随着边坡恢复年限的增加土壤颗粒向大团聚体聚集,〉5mm粒级团聚体含量表现为切挖43a边坡〉切挖3a边坡〉农田。切挖后恢复43a的裸露边坡〉2mm粒级团聚体占全土的82.85%,切挖后恢复3a的裸露边坡〉2mm粒级团聚体占77.48%。土壤有机碳和氮含量在对应各粒级团聚体中均表现为切挖43a边坡〉农田〉切挖3a边坡。切挖后恢复43a的裸露边坡粒径〉5mm团聚体中有机碳占全土有机碳含量的46.24%,切挖后恢复3a的裸露边坡为35.48%。切挖后恢复43a的边坡粒径〉5mm团聚体氮含量占全土氮含量的比例为56.62%,切挖后恢复3a的边坡为43.61%。各粒级团聚体的C/N研究结果显示,切挖后恢复43a的裸露边坡土壤团聚体C/N高于切挖后恢复3a的裸露边坡的C/N。而土壤团聚体磷含量表现为农田〉切挖43a边坡〉切挖3a边坡,其中切挖后恢复43a的边坡和切挖后恢复3a的边坡土壤各粒级团聚体磷含量之间差异不显著。研究认为,随着边坡恢复年限的增加,土壤结构逐渐恢复,土壤大团聚体（粒径〉5mm）所能提供的碳、氮和磷元素也逐渐增加。43 years recovery bare slopes and 3 years recovery bare slopes were chosen to reveal the distribution of soil aggregates in soil and the contents of carbon, nitrogen and phosphorus in soil aggregates. The farm-land was chosen as the control. Soil samples on the above slopes were screened through a series of 6 stainless sieves and were separated into 7 groups（〈0.25 mm, 0.25-0.5 mm, 0.5-1 mm, 1-2 mm, 2-3 mm, 3-5 mm,〉5 mm） according to aggregate size. The percentage of each group was calculated. Then, different soil aggregates were grind for soil nutrient analysis. The results showed that soil aggregates tended to be larger with the increase of revegetation years. The content of 〉5 mm soil aggregates was the largest on 43 years recovery bare slopes, then on 3 years recovery bare slopes, and finally on farmland. The percent of 2 mm soil aggregates on 43 years recovery bare slopes was 82.85%, and on 3 years recovery bare slopes, the percent was 77.48%. The contents of soil organic carbon and soil nitrogen in soil aggregates of different sizes showed the same tendency, which were the highest on 43 years recovery bare slopes and the lowest on 3 years recovery bare slopes. The content of organic carbon in 〉5 mm soil aggregates accounted for 46.24% of soil total organic carbon content on 43 years recovery bare slopes, while accounted 35.48% on 3 years recovery bare slopes. The nitrogen content in 〉5 mm soil aggregates accounted for 56. 62% of soil total nitrogen content on 43 years recovery bare slopes, while accounted 43.61% on 3 years recovery bare slopes. The C/N ratios of soil aggregates on 43 years recovery bare slopes were all significantly higher than those of 3 years recovery bare slopes. The phosphorus contents of soil aggregates decreased according to the sequence of farmland, 43 years recovery bare slopes, and 3 years recovery bare slopes. However, the differences in phosphorus contents of soil aggregates between 43 years recovery bare slopes and 3 years recovery bare slopes were not significant.

关 键 词：裸露边坡 团聚体颗粒 土壤养分 恢复年限 

分 类 号：S152.4[农业科学—土壤学] S154.1[农业科学—农业基础科学]