厚荚相思中龄林养分分布与生物地球化学循环  

Nutrient Distribution and Biogeochemical Cycling in Middle-Aged Acacia crassicarpa Plantation

作　　者：何斌[1] 余春和 何荣 刘莉[1] 罗柳娟[1] 刘红英[1] 

机构地区：[1]广西大学林学院,广西南宁530004 [2]广西七坡林场,广西南宁530001

出　　处：《华南农业大学学报》2012年第1期53-57,共5页Journal of South China Agricultural University

基　　金：广西自然科学基金(0640018);广西教育厅科研基金(2006-26);"十五"广西林业科学研究项目(2002-59)

摘　　要：采用标准样地法研究了7年生(中龄林)厚荚相思Acacia crassicarpa人工林10种养分元素(N、P、K、Ca、Mg、Fe、Mn、Zn、Cu和B)的分布和生物循环特点.结果表明:1)厚荚相思不同器官营养元素含量为:树叶>干皮>树枝>树根>干材,各器官中大量营养元素含量以N最高,其次是Ca或K,然后是Mg,P最低,微量元素含量则以Mn和Fe最高,其次是Zn和B,Cu最低;2)厚荚相思人工林养分贮存量为1 121.07 kg.hm-2,其中乔木层、林下植物层和凋落物层积累量依次为848.94、116.05和156.08 kg.hm-2,分别占总积累量的75.72%、10.35%和13.92%,林木中不同器官养分元素贮存量排序为:干材>树叶>树枝>干皮>树根;3)厚荚相思人工林养分年吸收量、归还量、存留量分别为261.87、140.59和121.28 kg.hm-2.年-1,循环系数为0.54,周转期为6.04年.因此,厚荚相思中龄林的营养元素利用率较低,归还速率较快,周转期较短,有利于林地地力的恢复和维持.The standard plot method was used to study the distribution and biological cycling of 10 nutri- ent elements （ N, P, K, Ca, Mg, Fe, Mn, Zn, Cu and B ） in the 7-year-old （middle-age） Acacia crassicarpa plantation. The results indicated that concentrations of the 10 nutrient elements in different organs of A. crassicarpa plantation were in the order of leaves 〉 bark 〉 branch 〉 root 〉 stem. The contents of N were the highest, K and Ca the second, Mg and P the lowest for macro-elements, whereas Mn and Fe were the highest, B and Zn the second, and Cu the lowest for micro-elements. The nutrient storage of the plantation was 1 121.08 kg·hm^-2 ,of which overstorey ofA. crassicarpa trees stored 848.94 kg·hm^-2 accounting for 75.72% ,forest floor 116. 05 kg·hm^-2 account for 10.35%, and standing litter 156.08 kg·hm^-2 account for 13.92%. The amounts of nutrient elements in different parts of trees was in the order of stem 〉 leaves 〉 branch 〉 bark 〉 root. The amounts of annual uptake, retention and return of 10 elements in the plantation were 261.87,140. 59 and 121.28 kg·hm^-2, respectively. The cycling coefficient and recycling period were 0. 54 and 6. 04. As was observed, the nutrient utilization efficiency in middle-aged A. crassicarpa plantation was lower, but the return rate was higher and the turnover period was shorter, resulting in the recovery and maintenance of forestland fertilization.

关 键 词：厚荚相思 中龄林 养分 生物地球化学循环 

分 类 号：S158.3[农业科学—土壤学]