凋落物去除对城市公园樟子松林土壤有机碳矿化及其温度敏感性的影响  

Effects of litter removal on soil organic carbon mineralization and temperature sensitivity of Pinus sylvestris var.mongolica forest in urban park

作　　者：杨轶晗 王彤 常宇飞 吴俊杰 王紫含 张丹 YANG Yihan;WANG Tong;CHANG Yufei;WU Junjie;WANG Zihan;ZHANG Dan(Changchun University,Changchun 130022,China)

机构地区：[1]长春大学,吉林长春130022

出　　处：《土壤与作物》2022年第3期298-306,共9页Soils and Crops

基　　金：吉林省教育厅项目(JJKH20200559KJ);长大学者攀登计划项目(ZKP202015);长春大学青年教师培育项目(ZKQ201913)。

摘　　要：凋落物是土壤有机质的重要来源,其数量和质量变化会影响土壤有机碳的矿化过程。城市公园中的树木落叶常被当作垃圾清理,这在导致土壤贫瘠化的同时还会影响土壤有机碳矿化及其温度敏感性,并进而对全球气候变化产生一定影响。本研究以吉林省长春市长春公园樟子松(Pinus sylvestris var.mongolica Litv.)林下土壤为研究对象,研究凋落物去除对土壤化学性质﹑有机碳矿化及其温度敏感性的影响。结果表明:去除凋落物后,樟子松林土壤化学性质与土壤有机碳矿化均发生变化。土壤pH值、碳氮比和电导率降低,全磷、全氮、土壤有机碳、易提取球囊霉素相关土壤蛋白和总球囊霉素相关土壤蛋白含量增加,其中全氮含量变化最明显,增加了53.1%。凋落物去除后,土壤有机碳矿化速率、土壤有机碳矿化累积CO_(2)排放量及土壤有机碳矿化温度敏感性系数(Q_(10))均有所增加,并且随着温度升高增幅逐渐增大。具体表现为:与有凋落物樟子松林相比,凋落物去除后,在10℃、20℃和30℃条件下,土壤有机碳矿化速率分别增加了1.17%、8.4%和16.4%,土壤有机碳矿化累积CO_(2)排放量分别增加了6.70%、1.98%和9.67%。而且Q_(10)在20℃/10℃和30℃/20℃条件下分别增加0.51%和8.99%。Litter is an important source of soil organic matter.The changes of its quantity and quality influence the mineralization of soil organic carbon.The fallen leaves of trees in urban parks are often cleaned up as garbage,which leads to soil barrenness and affects the stability of organic carbon mineralization and its temperature sensitivity,and thus may impact global climate change.In this study,the forest understory soil of Pinus sylvestris var.mongolica in Changchun Park,Changchun City,Jilin Province was selected in order to explore the effects of litter removal on forest soil chemical properties and soil organic carbon mineralization and its temperature sensitivity as well.The results showed that the removal of litter changed the soil chemical properties,soil organic carbon mineralization rate and its temperature sensitivity of Pinus sylvestris var.mongolica forest.Soil pH,C/N ratio and electrical conductivity decreased;total phosphorus,total nitrogen,soil organic carbon,easily extracted glomalin-related soil protein and total glomalin-related soil protein increased.The content of total nitrogen was with the most obvious change,increasing by 53.1%.After litter removal,soil organic carbon mineralization rate,accumulation CO_(2)emissions and SOC mineralization temperature sensitivity coefficient(Q_(10))increased with the increase in temperature.Specifically,after litter removal at 10℃,20℃and 30℃,the SOC mineralization rate of Pinus sylvestris var.mongolica forest increased by 1.17%,8.4%and 16.4%,the cumulative CO_(2)emissions of SOC mineralization increased by 6.70%,1.98%and 9.67%,respectively.The temperature sensitivity coefficient(Q_(10))of SOC mineralization increased by 0.51%and 8.99%at 20℃/10℃and 30℃/20℃,respectively.

关 键 词：城市公园 樟子松林 凋落物 有机碳矿化 温度敏感性 

分 类 号：X142[环境科学与工程—环境科学]