高寒沙地不同林龄中间锦鸡儿主要养分元素的分配及循环特征  

The Allocation and Cycling Characteristics of Main Nutrients for Caragana intermedia With Different Stand Age on Alpine Sandy Land

作　　者：李清雪[1,2] 贾志清 何凌仙子[1,2] 赵雪彬 羊秀本 LI Qing-xue;JIA Zhi-qing;HE Ling-xian-zi;ZHAO Xue-bin;Yang Xiu-ben(Institute of Ecological Conservation and Restoration,Chinese Academy of Forestry,Beijing 100091,China;Qinghai Gonghe Desert Ecosystem Research Station,Qinghai Gonghe 813005,Qinghai,China;Research Institute of Forestry,Chinese Academy of Forestry,Beijing 100091,China)

机构地区：[1]中国林业科学研究院生态保护与修复研究所,北京100091 [2]青海共和荒漠生态系统定位观测研究站,青海共和813005 [3]中国林业科学研究院林业研究所,北京100091

出　　处：《林业科学研究》2023年第3期119-128,共10页Forest Research

基　　金：中央级公益性科研院所基本科研业务费专项资金(CAFYBB2019MA008);国家重点研发计划课题(2022YFF1302503-2);中国林业科学研究院林业研究所林木培育重点实验室专项资金(ZDRIF20190)资助。

摘　　要：[目的]了解沙地人工植被恢复过程中主要养分元素的分配及循环特征有助于全面地认识植物适应环境的策略,为沙地植被的管理提供理论依据。[方法]以高寒沙地6、9、11、17和31年生中间锦鸡儿人工灌木林为研究对象,采用野外标准株全株收获法,对人工林N、P和K 3种主要养分元素的含量、积累、分配和生物循环特征进行研究。[结果](1)各组分中,叶和皮的养分含量最高,干的养分含量最低;随着林龄的增加,3个径级根系(粗根:直径>5 mm、中根:2 mm<直径≤5 mm、细根:直径≤2 mm)N含量和叶片P含量显著增加,细根的P和K含量、枝和中根的K含量显著降低;3个径级根系N含量与细根P和K含量呈极显著的负相关关系,中根和细根的N含量与枝和中根的K含量呈极显著的负相关关系。(2)根系养分积累量大于地上组分,其占总养分积累量的百分比随林龄的增加先增加后降低,在17年生人工林达到峰值,N、P和K积累量百分比分别达70%、66%和63%。(3)随着林龄增加,3种养分元素的利用系数降低,循环系数和周转期增加;K的利用系数和循环系数明显大于N和P,周转期明显小于N和P。[结论]高寒沙地中间锦鸡儿人工灌木林生长过程中将更多的养分分配给根系来适应严酷的自然环境,其固氮过程会消耗自身的K和P,其中,K元素的循环速率较快,流动性大。因此,建议对中间锦鸡儿人工灌木林的管护过程中适当添加K肥和P肥。[Objective]Understanding the allocation and cycling characteristics of the main nutrients in the process of artificial vegetation restoration on sandy land will help us fully understand the strategies of plant adaptation to the desert ecosystems,and provide theory for the vegetation management.[Method]This study was conducted in the shrub plantations of Caragana intermedia with different stand age of 6-,9-,11-,17-and 31-year-old on alpine sandy land.The whole plant of average shrubs was completely harvested for analysing the main nutrients N,P and K concentration,accumulation,allocation and cycling characteristics.[Result](1)In components,leaves and stem bark with the highest nutrient content,and stem wood with the lowest nutrient content.As the plantation age increased,N content in three root-diameter(coarse root:diameter>5 mm,medium root:2 mm<diameter≤5 mm,fine root:diameter≤2 mm)and P content in leaves increased significantly,whereas P and K contents in fine root,K contents in branches and medium root decreased significantly.The N contents of three root-diameters had a significant negative correlation with the P and K contents of fine root,and the N contents of medium and fine root had a significant negative correlation with the K contents of branches and medium root.(2)The nutrient accumulation of root was higher than aboveground components.The percentage of the nutrient accumulation of the root to the aboveground components firstly increased and then decreased as the plantation age increased.It peaked in 17-year-old plantation,and the percentage of N,P and K were 70%,66%and 63%,respectively.(3)As the plantation age increased,the utilization coefficient of the nutrients decreased,while the recycling period and cycling coefficient increased.Utilization coefficient and cycling coefficient of K were higher and recycling period was shorter than N and P in all plantations.[Conclusion]With the development of C.intermediate plantation on alpine sandy land,more nutrients were allocated to the root system to adapt

关 键 词：中间锦鸡儿人工灌木林 养分 分配 循环 高寒沙地 

分 类 号：S793.3[农业科学—林木遗传育种]