福建海岸防护林土壤矿质氮库及氮矿化动态  

Seasonal Variations in Soil Nitrogen Mineralization Under Protection Forest in Coastal Sand Dune of Fujian Province

作　　者：高伟 叶功富[2] 岳新建 刘海 陈智勇 Gao Wei;Ye Gongfu;Yue Xinjian;Liu Hai;Chen Zhiyong(Institute of Forest Ecology and Carbon Sequestration Measurement,Fujian Forestry Vocational and Technical College,Nanping 353000,China;Fujian Academy of Forestry Sciences,Fuzhou 350012,China;Fujian Forestry Survey and Planning Institute,Fuzhou 350001,China;Wu'an Forestry Workstation,Changtai Distric,Zhangzhou City,Zhangzhou 363900,China)

机构地区：[1]福建林业职业技术学院森林生态与碳汇计量研究所,福建南平353000 [2]福建省林业科学研究院,福建福州350012 [3]福建省林业调查规划院,福建福州350001 [4]漳州市长泰区武安林业工作站,福建漳州363900

出　　处：《南京师大学报(自然科学版)》2025年第2期62-73,共12页Journal of Nanjing Normal University(Natural Science Edition)

基　　金：福建省林业科学研究项目(2023FKJ31);福建省中青年教师教育科研项目重点项目(JZ230077).

摘　　要：为探明海岸沙地森林生态系统的净氮矿化特征及土壤无机氮的时空变化格局,揭示其矿化控制机理,为海岸带森林可持续经营提供理论依据,本研究选择福建海岸沙地5种防护林为对象,分别为次生林、木麻黄(Casuarina equisetifolia)林、湿地松(Pinus elliottii)林、厚荚相思(Acacia crassicarpa)林和尾巨桉(Eucalyptus urophylla×E.Grandis)林,采用原位连续培养法比较不同防护林0~10 cm土层的土壤矿质氮库及净氮矿化速率,探讨不同防护林土壤矿质氮库及净氮矿化速率与环境因子的关系.结果显示:(1)次生林总矿质氮含量显著高于人工林,人工林中厚荚相思林的铵态氮和总矿质氮含量最高,硝态氮是次生林无机氮的主要组分,占67.25%,人工林中土壤硝态氮含量占比为11.83%~27.53%.(2)海岸带森林土壤的净氮矿化速率和净硝化速率均呈明显的季节变化,次生林的年均净氮矿化速率和净硝化速率均显著高于人工林,厚荚相思林的净氮矿化速率显著高于其他3种人工林.(3)5种林分生长季平均土壤净氮矿化速率均显著高于非生长季,次生林、厚荚相思和木麻黄林生长季的平均硝化速率显著高于非生长季.(4)土壤矿质氮含量和氮转化速率与土壤pH、全氮、有效磷、可溶性有机碳氮、凋落物氮含量、细根氮含量、微生物量碳氮含量均呈显著正相关,与土壤容重、凋落物碳氮比和细根碳氮比呈显著负相关.次生林和湿地松林的土壤净氮矿化速率受温度和水分共同控制,尾巨桉林主要受土壤水分控制,厚荚相思和木麻黄林主要受温度控制.林分类型、土壤温度和含水量调控了土壤净氮矿化和硝化速率,采用次生林中乡土树种和厚荚相思改造提升海岸带森林有助于提高土壤矿质氮含量和氮转化速率.The objective of this study was to explore the characteristics of nitrogen(N)mineralization and the variation in soil inorganic N levels.Additionally,it aimed to reveal the mechanisms governing mineralization and provide a theoretical basis for the sustainable management of protection forests in the coastal sand dunes of Fujian Province.Five types of protective forests were selected,namely Secondary forests,Casuarina equisetifolia plantations,Pinus elliottii plantations,Acacia crassicarpa plantations,and Eucalyptus urophylla×E.Grandis plantations.The continuous cultivation method was adopted to compare the soil mineral N pool and N mineralization rates in the 0-10 cm soil layer among different protection forests.Moreover,the relationship between soil N mineralization and environmental factors was investigated.(1)The Secondary forests showed a significantly higher total mineral N content in comparison to the plantations.Among the plantations,Acacia crassicarpa had the highest levels of ammonium N and total mineral N.In the Secondary forests,nitrate N was the dominant form of inorganic N,accounting for 67.25%of the total.In contrast,the soil nitrate N content in the plantations ranged from 11.83%to 27.53%.(2)Both N mineralization and nitrification rates exhibited significant seasonal fluctuations.The annual mean soil N mineralization and nitrification rates in the Secondary forests were notably higher than those in the plantations.Remarkably,the soil N mineralization rate in the Acacia crassicarpa plantation was significantly higher than that in the other plantations.(3)The mean soil N mineralization rate during the growing season for all 5 forest types was significantly higher than that during the non-growing season.Similarly,the mean nitrification rate during the growing season in the Secondary forests,Acacia crassicarpa plantations,and Casuarina equisetifolia plantations was significantly higher than that during the non-growing season.(4)The soil mineral N content and N conversion rate were significantly and po

关 键 词：海岸沙地 防护林 矿质氮库 氮矿化速率 

分 类 号：S718.5[农业科学—林学]