有机物覆盖对女贞人工林不同根序细根C、N、P含量的影响  

Effects of organic mulching on C, N and P contents in different order fine roots of Ligustrum lucidum plantation

作　　者：王刚 孙晓丹 赵家豪 陈霞 关庆伟 WANG Gang;SUN Xiao-dan;ZHAO Jia-hao;CHEN Xia;GUAN Qing-wei(Co-Innovation Center of the Sustainable Forestry in Southern China,Nanjing 210037,China;College of Biology and the Environment,Nanjing Forestry University,Nanjing 210037,China;Marine Ecology Research Center,First Institute of Oceanography,Ministry of Natural Resources,Qingdao 266061,Shandong,China;Dr.Sun Yat-sen Mausoleum Administration,Nanjing 210014,China)

机构地区：[1]南方现代林业协同创新中心,南京210037 [2]南京林业大学生物与环境学院,南京210037 [3]自然资源部第一海洋研究所海洋生态研究中心,山东青岛266061 [4]中山陵园管理局,南京210014

出　　处：《生态学杂志》2022年第11期2098-2105,共8页Chinese Journal of Ecology

基　　金：国家科技支撑计划“环境友好型城镇景观林构建技术研究与示范”(2015BAD07B06-6);2015年南京市建设系统科研计划项目(Ks1501)资助。

摘　　要：以南京市16年生女贞(Ligustrum lucidum)人工林为研究对象,采用元素分析仪和钼锑抗比色法测定了3种强度的有机物覆盖处理(覆盖半径为80 cm,覆盖厚度分别为5、10、20 cm;覆盖物量分别为35、70、140 kg·株^(-1),记作T1、T2、T3)和空白对照CK对女贞不同根序细根C、N、P含量的影响,结合土壤理化性质以及细根形态和生物量解析其影响因素,为揭示细根养分利用过程和城市土壤近自然化管理提供科学依据。结果表明:(1)随着根序等级增加,细根C含量无明显变化,N、P含量减少,其中2、3级根中的N含量和4、5级根的N含量之间有显著差异(P<0.05),而P含量在各根序之间均有显著差异(P<0.05);(2)有机物覆盖后,细根的C含量在低级根(1、2级根)中减少,在高级根(3、4、5级根)中增加;(3)有机物覆盖后,细根的N含量在0~20 cm土层中减少,在20~40 cm土层中增加,且低级根的变化较显著(P<0.05);(4)有机物覆盖后,细根的P含量在0~20 cm土层减少;在20~40 cm土层中的2、3级根的P含量增加,但4、5级根的P含量减少,其中T2、T3处理影响较显著(P<0.05)。有机物覆盖改变了不同根序细根的C、N、P含量,加速了20~40 cm土层的元素循环,改善了土壤环境,是促进城市土壤近自然化管理的有效措施。In this study, an experiment was conducted with four levels of organic mulching(CK, T1, T2 and T3 with the thickness of 0, 5, 10 and 20 cm, respectively, i.e. with the coverage of 0, 35, 70 and 140 kg·tree, covered with a radius of 80 cm) in a 16-year-old Ligustrum lucidum plantation in Nanjing. We examined the effects of organic mulching on C, N and P contents in different order fine roots, and analyzed its affecting factors combined with soil physical and chemical properties, fine root morphology and biomass, aiming to provide scientific basis for understanding fine root nutrient utilization and near-nature management of urban soil. The C, N and P contents in different order fine roots were measured. The results showed that:(1) With increasing root orders, N and P contents in fine roots decreased, but C content showed no change. The N content in the 2 nd-and 3 rd-order roots was significantly different from that in 4 th-and 5 th-order root(P<0.05), while P content was significantly different among different root orders(P<0.05).(2) Compared with CK, C content under the three mulching treatments decreased in lower order(1 st-and 2 nd-order) roots, while increased in higher order(3 rd-, 4 th-and 5 th-order) roots.(3) N content of fine root in 0-20 cm soil layer under the three mulching treatments decreased compared with CK, increased in 20-40 cm soil layer, with the significant changes in low order roots(P<0.05).(4) P content of fine roots under the mulching treatments decreased in 0-20 cm soil layer. In 20-40 cm soil layer, mulching increased P content in 2 nd-and 3 rd-order roots and decreased it in 4 th-and 5 th-order roots. Organic mulching affects the C, N, P contents of fine roots in different root orders, accelerates soil element cycling in 20-40 cm soil layer, and improves soil environment. Organic mulching is an effective measure to promote the near-nature management of urban soils.

关 键 词：有机物覆盖 女贞人工林 根序 细根 C、N、P含量 

分 类 号：S687[农业科学—观赏园艺]