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林分年龄对落叶松人工林细根生物量的影响 被引量:3
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作者 高国强 程云环 +1 位作者 王政权 谷加存 《温带林业研究》 2019年第3期18-24,共7页
【目的】随着森林的发育过程,林木个体的生长和生物量分配,以及林分水平的结构和功能均发生了明显的变化。然而,细根生物量与林分年龄的联系,目前仍然了解有限。本研究以黑龙江省帽儿山地区兴安落叶松人工林为研究对象,比较了同一林分... 【目的】随着森林的发育过程,林木个体的生长和生物量分配,以及林分水平的结构和功能均发生了明显的变化。然而,细根生物量与林分年龄的联系,目前仍然了解有限。本研究以黑龙江省帽儿山地区兴安落叶松人工林为研究对象,比较了同一林分在19年和32年生时林分水平(单位面积)和单株水平细根生物量的垂直分布和季节动态,分析了影响细根生物量变化的林分与土壤因子,旨在明确林分年龄对细根生物量的影响和潜在的机制。【方法】在生长季内的5月、7月和9月,采用土钻法获取土壤0~30 cm深度细根并测定生物量,同时测定林分特征和土壤养分和水分含量。【结果】随林龄增加,落叶松人工林单位面积细根生物量显著下降,而单株细根生物量变化不显著;与19年生林分相比,32年生林分土壤表层(0~10 cm)细根生物量占总细根生物量的比例明显下降,土壤亚表层(10~20 cm)和底层(20~30 cm)细根生物量所占比例增加,呈现出细根向深层土壤增生的趋势。土壤表层(0~10cm)单位面积细根生物量随林分年龄的变化趋势与林分密度和胸高断面积、土壤铵态氮浓度变化有关,但是单株细根生物量受林分和土壤因子的影响均不显著。【结论】林分发育过程中,落叶松细根生物量降低,细根的资源吸收策略发生了明显的改变。 展开更多
关键词 落叶松 细根生物量 林分年龄 碳分配 养分吸收
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Variation of Coenzyme F_(420) Activity and Methane Yield in Landfill Simulation of Organic Waste 被引量:9
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作者 cheng yun-huan SANG Shu-xun +2 位作者 HUANG Hua-zhou LIU Xiao-juan OUYANG Jin-bao 《Journal of China University of Mining and Technology》 EI 2007年第3期403-408,共6页
A simulated landfill anaerobic bioreactor was used to characterize the anaerobic biodegradation and biogas generation of organic waste which was mainly composed of residuals of vegetables and foods. We investigated th... A simulated landfill anaerobic bioreactor was used to characterize the anaerobic biodegradation and biogas generation of organic waste which was mainly composed of residuals of vegetables and foods. We investigated the dynamics of the coenzyme F420 activity and determined correlations between biogas yields, methane yields, methane concentration and coenzyme F420 activity. The experiment was carded out under different conditions from control without any treatment, addition of Fe^3+, microorganism inoculation to a combination of Fe3+ addition and inoculation at a temperature of 36±2℃. The experiment was lasted 120 d and coenzyme F420 activity was analyzed using ultraviolet spectrophotornetry. Experimental results indicated that activity of the coenzyme F420 treated by Fe and microorganism inoculation increased substantially. The waste treated by inoculation had the greatest increase. When the waste was treated by Fe^3+, inoculation and the combination of Fe^3+ and inoculation, biogas yields increased by 46.9%, 132.6% and 153.1%, respectively; while the methane yields increased 4, 97 and 98 times. Methane concentration varied between 0 and 6% in the control reactor, from 0 to 14% for waste treated by the addition of Fe^3+, from 0 to 59% for waste treated by inoculation and from 0 to 63% for waste treated by Fe^3+ addition and inoculation. Correlations between coenzyme F420 activity and biogas production, methane production and methane concentration proved to be positively significant (p〈0.05), except for the control. Consequently, coenzyme F420 activity could be used as an index for monitoring the activity of methanogens during anaerobic biodegradation of the organic fraction of municipal solid waste. 展开更多
关键词 municipal solid waste (MSW) simulating landfill coenzyme F420 activity characteristic of methane generation
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