短枝木麻黄小枝衰老过程中K、Ca、Mg含量及其内吸收率季节动态  

Seasonal Changes of K,Ca,Mg Contents and Resorption Efficiency in Casuarina equisetifolia Branchlets During Senescence

作　　者：张尚炬[1] 林益明[1] 张立华[2] 叶功富[2] 黄珠兰[3] 林光辉[1] 

机构地区：[1]厦门大学生命科学学院,福建厦门361005 [2]福建省林业科学研究院,福建福州350012 [3]福建农林大学林学院,福建福州350002

出　　处：《厦门大学学报（自然科学版）》2010年第6期880-885,共6页Journal of Xiamen University：Natural Science

基　　金："973"计划前期研究专项(2009CB426306);国家"十一五"科技支撑计划项目(2009BADB2B0302);国家林业局南方山地用材林培育重点实验室资助项目;福建省科技重大项目(2006NZ0001-2)

摘　　要：对福建东山赤山林场8龄短枝木麻黄纯林小枝衰老过程中K、Ca和Mg元素的含量及其内吸收率的季节动态进行研究.短枝木麻黄成熟小枝中元素含量大小顺序为Ca>K>Mg,而衰老小枝中元素含量大小顺序为Ca>Mg>K.随着小枝的衰老,K和Mg含量下降(Mg在冬季除外),而Ca含量显著上升.K的内吸收率达60%以上,Mg的内吸收率较低(在冬季累积),而Ca在不同季节累积达90%以上.K的内吸收率在夏、秋季要高于冬、春季;Mg的内吸收率在夏季达到最高值;而Ca的内吸收率在各个季节并无显著差异.成熟小枝中不同的元素含量与其内吸收率之间的关系不尽相同,其中K、Ca含量与其内吸收率不相关;Mg含量与其内吸收率存在显著正相关(r=0.811,p=0.001).小枝衰老过程中较高的K的内吸收率反映了K是木麻黄林生长的关键元素之一,高的K的内吸收率是其重要的营养保存策略之一.Seasonal changes in K,Ca and Mg contents and their resorption efficiencies of branchlets of 8-years-old Casuarina equisetifolia pure forests were studied at Chishan Forestry Center of Dongshan County,Fujian Province,China.In mature branchlets,Ca content was the highest,followed by K and Mg,while in senescent branchlets,the order was CaMgK.During branchlet senescence,K and Mg contents decreased（except for Mg in winter） whereas Ca content increased accordingly.The resorption efficiency was above 60% for K,and was low for Mg in winter,while Ca accumulated more than 90%.The resorption efficiency of K was significantly higher in summer and autumn than that in winter and spring.The resorption efficiency of Mg was the highest in summer,while resorption efficiency of Ca was not significantly different in four seasons.The high resorption efficiency of K during branchlet senescence reflected that K was an important mineral nutrient for the growth of C.equisetifolia,high resorption efficiency of K was one of nutrient conservation strategies.

关 键 词：短枝木麻黄 K CA Mg 内吸收 季节动态 

分 类 号：S718.5[农业科学—林学]