福建林学院学报
福建林學院學報
복건림학원학보
JOURNAL OF FUJIAN COLLEGE OF FORESTRY
2009年
3期
237-242
,共6页
氮沉降%杉木人工林%凋落物%大量元素
氮沉降%杉木人工林%凋落物%大量元素
담침강%삼목인공림%조락물%대량원소
nitrogen deposition%Chinese fir plantation%litterfall%macronutrient
在杉木人工林中开展野外模拟氮沉降试验,以探讨森林凋落物对氮沉降增加的响应.通过对凋落物的化学分析发现,4种氮沉降[(N0)0、(N1)60、(N2)120、(N3)240 kg·hm~(-2)·a~(-1)]处理下5种大量元素的年平均含量大小顺序表现为N>Ca>K>Mg>P.相对于N0,N1、N2、N3处理增加了落叶中N、K、Mg的含量,其中使N平均含量分别增加了3.85%、7.69%、28.30%;但在一定程度上降低了P、Ca含量.经N0、N1、N2、N3处理,凋落物中N的年归还量分别为6.93、7.74、8.70、8.50 kg·hm-2;P为0.63、0.70、0.70 、0.60 kg·hm~(-2);K为3.67、4.29、4.50、4.11 kg·hm~(-2);Ca为4.72、5.09、5.06、4.47 kg·hm~(-2);Mg为2.14、2.63、2.35、2.05 kg·hm~(-2).N1、N2处理提高了凋落物中5种元素的年归还量,而N3处理则降低P、Ca、Mg的年归还量.各大量元素归还量在1a中均出现2个高峰期,其中第1次峰值出现在4月份,第2次峰值出现在6月或7月份.
在杉木人工林中開展野外模擬氮沉降試驗,以探討森林凋落物對氮沉降增加的響應.通過對凋落物的化學分析髮現,4種氮沉降[(N0)0、(N1)60、(N2)120、(N3)240 kg·hm~(-2)·a~(-1)]處理下5種大量元素的年平均含量大小順序錶現為N>Ca>K>Mg>P.相對于N0,N1、N2、N3處理增加瞭落葉中N、K、Mg的含量,其中使N平均含量分彆增加瞭3.85%、7.69%、28.30%;但在一定程度上降低瞭P、Ca含量.經N0、N1、N2、N3處理,凋落物中N的年歸還量分彆為6.93、7.74、8.70、8.50 kg·hm-2;P為0.63、0.70、0.70 、0.60 kg·hm~(-2);K為3.67、4.29、4.50、4.11 kg·hm~(-2);Ca為4.72、5.09、5.06、4.47 kg·hm~(-2);Mg為2.14、2.63、2.35、2.05 kg·hm~(-2).N1、N2處理提高瞭凋落物中5種元素的年歸還量,而N3處理則降低P、Ca、Mg的年歸還量.各大量元素歸還量在1a中均齣現2箇高峰期,其中第1次峰值齣現在4月份,第2次峰值齣現在6月或7月份.
재삼목인공림중개전야외모의담침강시험,이탐토삼림조락물대담침강증가적향응.통과대조락물적화학분석발현,4충담침강[(N0)0、(N1)60、(N2)120、(N3)240 kg·hm~(-2)·a~(-1)]처리하5충대량원소적년평균함량대소순서표현위N>Ca>K>Mg>P.상대우N0,N1、N2、N3처리증가료락협중N、K、Mg적함량,기중사N평균함량분별증가료3.85%、7.69%、28.30%;단재일정정도상강저료P、Ca함량.경N0、N1、N2、N3처리,조락물중N적년귀환량분별위6.93、7.74、8.70、8.50 kg·hm-2;P위0.63、0.70、0.70 、0.60 kg·hm~(-2);K위3.67、4.29、4.50、4.11 kg·hm~(-2);Ca위4.72、5.09、5.06、4.47 kg·hm~(-2);Mg위2.14、2.63、2.35、2.05 kg·hm~(-2).N1、N2처리제고료조락물중5충원소적년귀환량,이N3처리칙강저P、Ca、Mg적년귀환량.각대량원소귀환량재1a중균출현2개고봉기,기중제1차봉치출현재4월빈,제2차봉치출현재6월혹7월빈.
A field experiment was conducted to study the effect of simulated nitrogen on litterfall in a Chinese fir plantation. Urea [CO(NH2)2] was added at three doses, N1, N2 and N3, 60, 120 and 240 kg·hm~(-2)·a~(-1), respectively. The results showed that the annual average concentrations of the macronutrients in litterfall decreased consistently in the following order N>Ca>K>Mg>P. All N treatments elevated the average concentrations of N, K and Mg, but reduced P and Ca in the litterfall; among them N increased by 3.85%, 7.69% and 28.30%, respectively, compared with the control (N0). Through litterfall production, the annual N flux to the forest floor under the four treatments (N0, N1, N2 and N3) was estimated, respectively, at 6.93, 7.74, 8.70 and 8.50 kg·hm~(-2); P at 0.63, 0.70, 0.70 and 0.60 kg·hm~(-2); K at 3.67, 4.29, 4.50 and 4.11 kg·hm~(-2); Ca at 4.72, 5.09, 5.06 and 4.47 kg·hm~(-2); Mg at 2.14, 2.63, 2.35 and 2.05 kg·hm~(-2). The data suggested that the annual flux of the five elements responded positively to N1 and N2 treatments, but negatively to N3 for the P, Ca, Mg elements. The macronutrient flux through litterfall exhibited two pronounced peaks in the year, the first one occurring consistently in April, the second in June or July.
