黑木相思与尾叶桉苗期氮素传递的研究  

Study on Nitrogen Transfer between Acacia melanoxylon and Eucalytups urophylla Seedlings

作　　者：廖绍波[1] 陆俊锟[1] 江业根[1] 王胜坤[1] 

机构地区：[1]中国林业科学研究院热带林业研究所,广东广州510520

出　　处：《林业科学研究》2015年第5期640-645,共6页Forest Research

基　　金：国家林业公益性行业科研专项"功能微生物在低碳林业中的应用研究"(201004075);中央级公益性科研院所基本科研业务费专项资金(RITFYWZX201207)

摘　　要：以尾叶桉、黑木相思苗木混栽为研究对象,采用15N土壤和叶片标记法,在温室盆栽下研究2种植物间在根系完全隔离、部分隔离及无隔离处理下的生长变化及N素传递。结果表明:黑木相思的苗高、地径及生物量等生长指标随着根系隔离的减少而逐渐降低;相反,尾叶桉在根系无隔离处理下,其生长指标都要显著高于根系完全隔离处理,结果表明尾叶桉具有强大的养分吸收能力,混栽条件下会抑制黑木相思的生长。在15N土壤或叶片标记下,尾叶桉在根系部分隔离、无隔离下的总15N含量显著高于完全隔离处理(5.0和59.6倍);在土壤标记下,根系无隔离处理的黑木相思总15N含量显著低于完全隔离、部分隔离处理,而在叶片标记下的完全隔离黑木相思,其总15N含量显著低于其余2种处理。无论土壤或是叶片标记,黑木相思都能将N素传递至相邻尾叶桉,其N素传递率、传递量随着根系隔离的减少而提高。研究结果表明尾叶桉、黑木相思间能通过土壤渗透等方式传递N素,为桉树、相思的混交模式提供可靠的理论依据。Nitrogen （N） can be transferred between plants. In order to remain N balance between plants and fertili- ty of soil, mixture of N2-fixing plants and non-N2-fixing plants provide good system for forestry. To investigate whether the root isolation （ e. g. complete isolation, partial isolation and no isolation） could account for the mixed Acacia melanoxylon and Eucalytups urophylla growth response and N transfer, the authors assessed N transfer by 15^N-soil/leaf-label method in a pot study. The height, diameter and biomass of 7-month-old A. rnelanoxylon were lower when the root isolation reducing. By contrast, the growth index were significantly higher in E. urophylla grown under no isolation than that of grown in complete isolation, indicating E. urophylla owns stronger absorbing capacity than A. melanoxylon. In both 15^N-soil/leaf-label treatments, the total 15^N content of E. urophylla was significantly higher （5.0 and 59.6 times） in partial or no isolation than in complete isolation respectively. In 15^N-soil-label sta- tus, the total 15 N content in A. melanoxylon grown by no isolation were significantly lower than that of the other two isolation treatments. Nevertheless, by 15^N-leaf-label, A. melanoxylon in complete isolation had significantly lower total 15^N content than the other isolation treatments. Irrespective of the labeled status, A. melanoxylon always trans-ferred the N to neighbor E. urophylla. The percentage and amount of N transfer increased with the root isolation re- ducing.

关 键 词：黑木相思 尾叶桉 氮素传递 生长表现 

分 类 号：S723.1[农业科学—林木遗传育种]