摘要
为探究有机覆盖对城市森林土壤有机碳矿化及其氧化稳定性特征的影响,采集北京市鹫峰国家森林公园土壤,进行室内培养,研究不覆盖(CK)、木片覆盖(M_(w))、堆肥覆盖(M_(c))、上层木片覆盖+下层堆肥覆盖(M_(w+c))4种条件下土壤有机碳矿化特征及氧化稳定组分变化。结果表明,不同有机覆盖方式均显著影响了土壤有机碳(SOC)矿化(P<0.05),M_(c)、M_(w+c)、M_(w)处理的有机碳累积矿化量分别是CK的1.77倍、2.93倍和3.98倍,M_(w)处理累积矿化量分配比和Cp/SOC值(土壤有机碳矿化潜能占土壤有机碳含量的比重)显著高于M_(c)和M_(w+c)处理(P<0.05),说明M_(c)和M_(w+c)处理的固碳潜力好于M_(w)处理。不同有机覆盖方式显著提升了土壤有机碳及其氧化稳定组分含量(P<0.05),M_(w+c)处理的增幅最明显,土壤有机碳含量比CK提高了29.14%;高活性有机碳组分和低活性有机碳组分含量较CK分别提高了20%和37.14%。有机覆盖提高了土壤有机碳稳定指数,降低了活性指数,表明有机覆盖增强了土壤有机碳稳定性。有机碳累积矿化量与高活性有机碳组分呈极显著正相关(P<0.01),与土壤有机碳和低活性有机碳组分呈显著正相关(P<0.05)。综合土壤有机碳矿化特征及其氧化稳定组分的变化来看,上层木片+下层堆肥的覆盖模式,既能提高土壤的固碳潜力,又能协调有机碳矿化与稳定性特征。
In order to explore the effects of organic mulching on soil organic carbon(SOC)mineralization and oxidation stability in urban forest,soil samples were collected from Jiufeng National Forest Park for incubation experiment.Four treatments were applied:1)no organic mulch(CK);2)wood chips alone(M_(w));3)wood composts alone(M_(c));4)the upper layer wood chips+the lower layer wood composts(M_(w+c)).The results showed that organic mulching significantly affected SOC mineralization in the soil(P<0.05),and the cumulative mineralization of SOC under M_(c),M_(w+c)and M_(w) treatments was 1.77,2.93 and 3.98 times that of CK.Ratios of cumulative mineralization amount to SOC contents and Cp/SOC under M_(w) treatment was significantly higher than those of M_(c) and M_(w+c)treatments(P<0.05),which showed that M_(c) and M_(w+c)treatments had higher carbon sequestration capacity than M_(w) treatment.Organic mulching significantly increased SOC contents and oxidation stability fractions(P<0.05).Compared with CK,SOC content of M_(w+c)was increased by 29.14%,and the contents of very active organic carbon(VAC)and partially organic carbon(PAC)were increased by 20%and 37.14%,respectively.Organic mulching increased SOC stability index and decreased activity index,indicating that organic mulching enhanced SOC stability.The cumulative mineralization of organic carbon was very significantly positively correlated with VAC(P<0.01),and significantly positively correlated with SOC and PAC(P<0.05).As a whole,M_(w+c)treatment is beneficial for soil organic carbon sequestration,and it also can balance the organic carbon mineralization and sequestration.
作者
周伟
孙向阳
李素艳
董文萱
杜田甜
郑燚
范志辉
ZHOU Wei;SUN Xiangyang;LI Suyan;DONG Wenxuan;DU Tiantian;ZHENG Yi;FAN Zhihui(Key Laboratory of Forest Cultivation and Protection of Ministry of Education,College of Forestry,Beijing Forestry University,Beijing 100083,China)
出处
《土壤》
CAS
CSCD
北大核心
2022年第4期779-786,共8页
Soils
基金
北京市自然科学基金项目(6202021)资助。
关键词
有机覆盖
城市森林
有机碳矿化
氧化稳定组分
Organic mulching
Urban forest
Organic carbon mineralization
Oxidation stability fractions
