共查询到18条相似文献，搜索用时 390 毫秒
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细根是植物根系最重要的组成部分,作为衡量植物生产力的重要因素,对森林生态系统生产力具有重要影响。前人研究表明,细根的生产与周转对细根的寿命、分解和生物量估算具有重要意义,并且会影响森林生态系统碳、养分和水循环过程。文中系统阐述了细根生产和周转的研究进展,介绍了细根的3种主要研究方法（根钻法、内生长法和微根管法）,进一步分析细根生产和周转的影响因素,即除了受植物内在因子（细根构型、根序和化学组成）的制约外,细根生产和周转还受到纬度、海拔、气候、土壤条件、土层深度等环境因子及生物因子的影响;探讨了在植物细根研究中存在的问题,并对今后的发展趋势进行了展望,以期为植物细根深入研究和根系生态学学科发展提供参考。 相似文献
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细根(直径≤2 mm)是树木吸收养分和水分的主要器官,其生产和周转构成了森林生态系统物质循环和能量流动的主体。由于细根的测定方法不同会导致细根生物量、生产、周转和寿命等指标的差异。同时,细根的测定方法均有一定的局限性和缺陷。因此,细根的测定方法已经成为目前细根生态学领域的热点问题之一。近年来细根的研究方法主要以根钻法、内生长法、微根管法和土壤碳通量法为主。文章就这几种常用方法对细根生物量、生产、周转、寿命等指标的研究方法进行评述。 相似文献
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细根在森林生态系统C平衡和养分循环中的重要作用已为大量研究所证实，树木有赖于细根吸收水分和养分，而细根对环境胁迫比较敏感，因此细根动态可指示环境变化，还可反映树木的健康状态，影响树木细根生产和周转的因子很多，本文在收集大量研究文献基础上，讨论了文献基础上，讨论了土壤养分，水分、pH值，温度等环境因子以及大气CO2增长对树木细根分布，生物量，生产和周转的影响，以期为我国开展细根生态学研究提供参考。 相似文献
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油松蒙古栎混交林细根生物量及养分现存量研究 总被引：1，自引：0，他引：1
应用固定样地调查生物量的方法,在辽宁省建平县干旱所南大山试验区进行了油松蒙古栎混交林细根生物量和养分现存量的研究。结果表明,混交林的细根生物量大于油松纯林,两树种混栽后蒙古栎能促进油松的细根生长,提高油松细根生物量在混交林中的比例;混交林细根在各土层中分布得比纯林更均匀、更合理,两树种根系生长协调;混交林细根N、P养分现存量分别是纯林的1.1倍和1.2倍,可见混交林细根具有比纯林更高的养分积累和周转能力;纯林和混交林人工林的各径级活细根和死细根养分现存量都随细根径级的增加而减少,说明≤2 mm径级的细根在细根的养分循环中起主导作用。 相似文献
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森林细根生产和周转研究 总被引：86，自引：10，他引：86
随着近 2 0多年来对细根功能的深入认识和研究方法的发展 ,林分细根生物量、生产和周转及其与环境因子的关系成为森林生态学的研究热点之一 ,开展了大量研究。本文在收集了大量研究报道基础上 ,对森林细根研究结果进行综述。结果如下 :细根 (直径 <2～ 5mm)生物量变化在 46～ 2 80 5g·m- 2 之间 ,大部分在 10 0～ 10 0 0g·m- 2 ;细根生物量分别占地下部分总生物量和林分总生物量的 3%～ 30 %和 0 .5 %～ 10 % ;北方常绿针叶林平均细根生物量最低 (2 16g·m- 2 ) ,热带常绿阔叶林最高 (10 87g·m- 2 )。细根年净生产量 2 0～ 1317g·m- 2 ·a- 1 ,占林分总净初级生产量的3%～ 84% ,大部分在 10 %～ 6 0 % ;从北方森林到温带、亚热带至热带森林 ,细根生产量呈增加趋势 ;针叶林细根生产在总净初级生产中的比例小于阔叶林 (常绿和落叶 )。树木细根生命周期短至数天 ,长达数年。细根年周转率 4.3%～ 2 73.2 % ,阔叶林细根周转率低于针叶林。细根生产和周转是土壤碳和养分的重要来源 ,细根生产向林地输入的生物量占总输入 (细根生产和地上枯落物输入 )的 6 .2 %～ 88.7%。除气候森林类型外 ,森林生态系统细根生物量、分布、生产、周转还因季节、土壤类型、立地条件和生长发育阶段而异。同时 ,还受树木体内碳 相似文献
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《Scandinavian Journal of Forest Research》2012,27(6):469-472
Abstract Comprehensive data from different research workers were included in the compilation of a carbon budget for a 14-year-old Scots pine (Pinus sylvestris) in the late 1970s, within the SWECON project (the Swedish Coniferous Forest Project). In a recent paper in the Scandinavian Journal of Forest Research, the authors published a surprisingly high turnover rate of fine roots (7.4 year?1), maintaining that they had used our old SWECON data from our sequential soil coring. However, a close examination of our original data suggests a turnover of fine-root biomass of 2.3 and for fine-root standing crop (biomass+necromass) of 2.0 year?1. Supporting evidence is available from other forest sites suggesting that our turnover rates were correctly estimated. Certain errors may exist in different parts of our old carbon budget, e.g. some measurements were carried out for different parts of the tree, while others were attributed to the whole stand. The sequential soil coring technique still remains the best technique available for fine-root growth and turnover estimates in forest stands. 相似文献
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Kyotaro Noguchi Qingmin Han Masatake G. Araki Tatsuro Kawasaki Shinji Kaneko Masamichi Takahashi Yukihiro Chiba 《Journal of Forest Research》2011,16(4):284-291
Fine roots play a key role in carbon and nutrient dynamics in forested ecosystems. Fine-root dynamics can be significantly
affected by forest management practices such as thinning, but research on this topic is limited. This study examined dynamics
of fine roots <1 mm in diameter in a 10-year-old stand of hinoki cypress (Chamaecyparis obtusa) for 3 years following thinning (65% in basal area). Fine-root production and mortality rates were estimated using a minirhizotron
technique in combination with soil coring. In both thinned and un-thinned control plots, fine-root elongation occurred from
early spring to winter (March to December) and fluctuated seasonally. In the thinned and the control plots, the annual fine-root
production rates were estimated to be 101 and 120 g m−2 year−1, respectively, whereas the estimated annual fine-root mortality rates were 77 and 69 g m−2 year−1, respectively. At 3 years after thinning, live fine-root biomass was significantly smaller in the thinned plot (143 g m−2) than in the control plot (218 g m−2), whereas dead fine-root biomass was not (147 and 103 g m−2, respectively). Morphological and physiological indices of fine roots such as diameter, specific root length, and root tissue
density of the live fine roots was similar in both plots. These results suggested that thinning tended to decrease biomass
and production of fine roots, but the effects on characteristics of fine roots would be less evident. 相似文献
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作为陆地生态系统的主体,森林生态系统的碳循环与碳蓄积对研究陆地生态系统碳循环起着重要作用.生物量、生产力、土壤有机质以及凋落物量及其分解等相互关系决定了森林生态系统的碳库量和碳交换量.本文简单地介绍了在碳蓄积研究中森林生物量和生产力的几种研究方法,并对研究过程中的问题(大尺度生物量的精确估算,地下生物量的研究,森林生态系统土壤碳库估算)进行了探讨. 相似文献
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Biomass and production of fine roots in Japanese forests 总被引：1，自引：0，他引：1
Kyotaro Noguchi Bohdan Konôpka Takami Satomura Shinji Kaneko Masamichi Takahashi 《Journal of Forest Research》2007,12(2):83-95
To better understand the control of fine-root dynamics in Japanese forests, we reviewed studies conducted in Japan on fine-root
biomass and production. Most of the data on fine-root biomass were obtained for conifer plantations in limited regions; the
average fine-root biomass of dominant trees ranged from ∼50 g m−2 for Pinus species (n = 3) to ∼600 g m−2 for Cryptomeria japonica (n = 4) and Chamaecyparis obtusa (n = 3). These values are comparable with or less than those reported for other temperate forests mainly in North America or
Europe. Information on fine-root production in Japanese forests remains limited. Fine-root production accounted for ∼30% of
the net primary productivity in two deciduous forests, but similar data was not reported for coniferous forests in Japan.
In Japanese forests, slope position is a key parameter controlling fine-root biomass that is greater on upper slopes than
on lower slopes, probably because soil resource availability decreases upslope. Studies in manipulated soil environments (e.g.,
removing throughfall to simulate drought) also suggested that fine-root biomass and production were greatly affected by altered
soil environments. Physiological control of fine-root dynamics was recently discussed via anatomical analyses of Chamaecyparis obtusa. Findings from Japanese studies generally support data on fine-root biomass and production obtained from other temperate
regions. Further attempts to elucidate the influence of slope position (soil resource availability) on fine-root production
would be useful to gain a more detailed understanding of the fine-root dynamics in Japanese forests. 相似文献
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森林生态系统粗木质残体生态功能研究 总被引：4，自引：0，他引：4
WU Jia-bing GUAN De-xin HAN Shi-jie ZHANG Mi JIN Chang-jie 《林业研究》2005,16(3):247-252
粗木质残体(CWD)是森林生态系统中重要的结构性与功能性单元。本文在对国内外CWD 研究历史进行简要回顾的基础上,对其生态功能及其分解过程进行了系统分析。指出了目前CWD 研究的热点及存在的问题,并建议加强对CWD生态服务功能的定量化研究,为其在维持生物多样性、生产力和其它生态过程方面的经营管理提供科学指导。参57。 相似文献