摘要
对福建三明福建柏和杉木人工林细根生产力、分布及周转进行了为期 3年的研究 ,结果表明 ,福建柏年均细根生物量达 389 7g·m- 2 ,是杉木林 (2 77 2g·m- 2 )的 1 4 1倍 ;活细根年均生物量达 2 16 3g·m- 2 ,是杉木林(14 8 4g·m- 2 )的 1 4 6倍 ;<0 5mm细根生物量 (2 4 2 2g·m- 2 )则是杉木林 (12 4 7g·m- 2 )的 1 94倍 ,其占总细根生物量比例 (6 1 2 % )比杉木林 (4 5 0 % )的高出 16 2 %。福建柏和杉木细根垂直分布在 0～ 10cm土层差异最大 ,该层福建柏总细根密度 (14 4 2g·m- 2 )是杉木 (70 2g·m- 2 )的 2 1倍。福建柏林活细根生物量 1年只出现 1次峰值 (3月 ) ,而杉木林活细根则出现 2次 (3月和 9月 )。福建柏不同径级细根第 1年分散速率及分解系数均低于杉木的。福建柏林细根年净生产量 (32 0 2g·m- 2 a- 1 )和细根年死亡量 (32 6 5g·m- 2 a- 1 ) ,分别是杉木林 (2 5 1 3和 2 4 9 2g·m- 2 a- 1 )的 1 2 7倍和 1 31倍。福建柏细根年均周转速率为 1 4 8a- 1 ,低于杉木林的 (1 6 9a- 1 )。福建柏和杉木细根生物量分别仅占其乔木层生物量的 1 70 %和 1 18% ,但细根净生产力却分别占其乔木层总净生产力的 19 84 %和19 2 1% ,细根年死亡量分别占地上部分凋落物量的 4 8 74 %和 5 1 0
In many forest ecosystems,the production,death and decomposition of fine root appear to play a very important role in carbon and nutrient cycling,due to their rapid turnover rates.During 1999—2001,the production,distribution and turnover of fine roots were comparatively studied between two coniferous plantations(Fokienia hodginsii and Cunninghamia lanceolata) in Sanming,Fujian. Mean standing crop of total fine roots and living fine roots of F.hodginsii amounted to 389.7 g·m -2 and 216.3 g·m -2,respectively,being 1.41 times and 1.46 times as high as that of Chinese Fir,roots less than 0.5 mm in diameter(242.2 g·m -2)constituted 61.2% of total fine root standing crop,compared with 45.0% in Chinese Fir stand.The maximum differences of fine root density between two stands occurred in the soil layers of 0～10 cm,where root density of F.hodginsii(144.2 g·m -2)was 2.1 times as much as that of Chinese Fir(70.2 g·m -2).Living fine root biomass peaked in March in F.hodginsii stand,and peaked in March and September in Chinese Fir stand.The weight loss rates of roots after the first year of decomposition and the decomposition rate coefficient of F.hodginsii were lower than those of Chinese Fir.Annual fine root net production and mortality of F.hodginsii were 320.2 and 326.5 g·m -2a -1,respectively,being 1.27 times and 1.31 times as high as that of Chinese Fir,though a lower fine root turnover rate was found for F.hodginsii(1.48 a -1vs 1.69 a -1).In F.hodginsii and Chinese Fir stands,fine roots each contributed to 19.84% and 19.21% of total NPP and equaled 48.74% and 51.00% of annual aboveground litterfall of tree layer,albeit they account for only 1.70% and 1.18% of total tree layer biomass,respectively.
出处
《林业科学》
EI
CAS
CSCD
北大核心
2004年第4期15-21,共7页
Scientia Silvae Sinicae
基金
国家自然科学基金 ( 3 0 170 770 )
教育部高等学校优秀青年教师教学科研奖励计划
教育部高等学校骨干教师资助计划
福建省自然科学基金 (B0 110 0 2 5 )
福建省重大基础研究项目 ( 2 0 0 0 -F -0 0 4)资助
关键词
福建柏
杉木
人工林
细根
净生产力
分布
周转速率
Fokienia hodginsii,Cunninghamia lanceolata,Fine root,Distribution, Net productivity, Turnover rate
