| 题名 | 青藏高原东缘亚高山针叶林人工恢复过程中的土壤呼吸研究 |
| 作者 | 周非飞 |
| 学位类别 | 硕士 |
| 答辩日期 | 2009-05-01 |
| 导师 | 刘庆 ; 林波 |
| 关键词 | 云杉林 土壤呼吸 土壤自养呼吸 土壤异养呼吸 spruce plantation soil respiration soil autotrophic respiration soil heterotrophic respiration |
| 其他题名 | Soil Respiration in Artificial Restoration Process of Subalpine Coniferous Forest in the Eastern Part of Qinghai-Tibet Plateau |
| 中文摘要 | 青藏高原东部亚高山针叶林是我国西南林区森林的主体，对全球陆地生态系统碳贮存发挥着重要贡献。该区域也是国际碳平衡研究的重要区域，目前国内对该区域森林生态系统的碳平衡研究中主要采用世界相应植被类型的平均土壤呼吸速率估算其土壤呼吸碳释放量。这些人工针叶林在不同恢复阶段其土壤呼吸碳释放量各不相同，采用其它地区相应植被类型的平均土壤呼吸速率值并不能精确评估该区域森林生态系统的碳平衡，因此，对不同恢复阶段土壤呼吸变化特征的研究就显得十分重要。 本研究主要选择青藏高原东部的亚高山天然云杉林和3种不同恢复阶段（22a、35a、65a）的人工云杉林作为研究对象，研究人工林恢复过程中的土壤呼吸特征以及通量；区分不同恢复阶段土壤自养、异养呼吸；阐明高寒森林土壤呼吸的温度敏感性。 采用动态密闭气室红外CO2分析法，在2007.11~2008.10间对青藏高原东缘22 a、35 a、65 a人工云杉林和天然林的土壤呼吸进行连续定位测定，并用挖壕沟法区分土壤自养呼吸和异养呼吸。测量土壤呼吸的同时，分别用6300数字土壤温度计和土壤水分计测量土壤5 cm的土壤温度（T）和体积含水量（W），从安装于65a云杉林样地中的AR5数据采集器获取T和W的长期连续监测数据。于2007年11月在每个样地挖10个土壤剖面，每个剖面取0-10cm、10-20cm、20-30cm土样，然后将各层土样混匀，带回实验室测量土壤有机碳和土壤微生物生物量碳。 人工云杉林和天然云杉林土壤5cm 温度均存在明显的季节变化。人工云杉林和天然云杉林土壤5cm 水分季节变化不明显各林地土壤温度差异不显著。土壤5 cm温度与土壤呼吸速率相关性极显著，土壤5 cm水分与土壤呼吸速率相关性不显著。不同恢复阶段人工云杉林土壤呼吸速率与土壤5cm温度指数回归模型方程能够较好的反应土壤呼吸速率，22a、35a、65a人工云杉林和天然云杉林的相应方程分别能够解释土壤呼吸速率的76.7%、74.2%、75.7%、71.0%。 在22a、35a、65a人工云杉林和天然云杉林样地中,通过模型模拟得到土壤呼吸速率在0.77～9.87mmolm-2 s-1之间,总体平均值(±SD)为2.81±1.71 mmolm-2 s-1。土壤呼吸速率从春季到夏季随着土壤温度波动地增加到最高值，随后在秋冬季节土壤呼吸速率逐渐降低，最低值出现在冬季。22a、35a、65a人工云杉林和天然云杉林土壤呼吸年通量分别为：1004.24、792.08、975.32、1070.2 g.C.m-2.year-1。人工林在20a~35a的初期恢复过程中，土壤呼吸通量呈现出下降趋势，而后在35a~65a-原始林的恢复过程中土壤呼吸通量逐渐增加。 22a、35a、65a人工云杉林和天然云杉林土壤自养呼吸通量依次340.79±36.43、253.38±9.37、350.11±15.69、357.27±11.88 g.C.m-2year-1。异养呼吸通量依次为656.69±17.22、543.92±3.35、607.62±29.93、712.97±17.30 g.C.m-2year-1。自养、异养呼吸通量从大到小均为：天然云杉林＞22a 人工云杉林、65a人工云杉林＞35a人工云杉林。 0-10、10-20、20-30 cm土壤层总有机碳(TOC)具有类似的变化规律，从22a人工云杉林到65a人工云杉林降低，从65 a人工云杉林到天然云杉林阶段有所增加。0-10、10-20、20-30 cm土壤层微生物碳(MBC)的变化规律与土壤总有机碳(TOC)相同。TOC与土壤异养呼吸相通量关性极显著，与土壤总呼吸通量相关性显著；MBC与土壤总呼吸通量、土壤异养呼吸通量相关性均显著, TOC、MBC与土壤自养呼吸通量的相关性均不显著，表明土壤碳主要通过影响土壤异养呼吸，从而影响土壤总呼吸。 22a、35a、65a人工云杉林和天然云杉林非生长季和生长季Q10值分别为：4.59、6.54、4.77、3.18和4.17、4.66、3.11、2.74。各林地非生长季Q10值节均明显要高于生长季。单因素方差分析结果表明，随着森林的恢复更新除（22a人工云杉林外），Q10值逐渐降低。 The subalpine coniferous forests of eastern Qinghai-Tibetan Plateau are the main parts of forests in southwest of China and play a very important role in carbon pool of global terrene ecosystem. This area is a very important region of international carbon balance research. Right now soil respiration carbon emission of this area are mainly estimated by the average value of the similar ecosystem in the other world. Because the carbon emissions of coniferous forests in different ages are the same, the way mentioned above can not accurately estimate the carbon balance of the forest ecosystem in this area. Only measuring the soil respiration of coniferous forests in different ages can accurately estimate the carbon balance of the forest ecosystem in this area. We have chosen three spruce plantations in different ages (22-year, 35-year, 65-year) and one natural spruce forest as our research objects. Mainly interested in the carbon emission fluxes and regulation of soil respiration in artificial restoration process of subalpine coniferous forests, partitioning and quantifying the carbon emission fluxes of soil autotrophic and heterotrophic respiration, clarifying the temperature sensitivity of soil respiration in forests of high latitude. Soil respiration of three spruce plantations in different ages (22-year, 35-year, 65-year) and one natural spruce forest was continuously measured by closed CO2 IRGS dynamic chamber between Nov.2007 and Oct. 2008. In this study, we used trenching plots and infrared gas exchange analyzer approaches to determine heterotrophic and autotrophic respiration. Soil temperature at 5 cm was measured by 6300 digital temperature probe and soil water content was measured by digital water probe. Continuously soil temperature and water content date of every 30 minutes were obtained by AR5 date collector of 65a spruce plantations. We dug ten soil profiles and obtained soil samples of 0-10cm, 10-20cm, 20-30cm at each profiles in Nov.2007. Soil samples were used to measured soil total organic carbon and microbe carbon. Soil temperature at 5 cm of spruce plantations and natural spruce forest all have prominent seasonal variations, while soil water contents at 5 cm have not. Soil respiration in all of the forests have significant correlation with soil temperature at 5 cm and have insignificant correlation with soil water content at 5 cm. The temperature exponential equations of 22-year, 35-year, 65-year spruce plantation and natural spruce forest can explain 76.7%,74.2%,75.7%,71.0% of soil respiration respectively. Soil respiration rates of 22-year, 35-year, 65-year spruce plantation and natural spruce forest modeled by temperature exponential equations are between 0.77 and 9.87 mmolm-2 s-1 and the average (±SD) is 2.81±1.71 mmolm-2 s-1. Soil respiration increase from spring to summer while decrease after autumn. The highest value of soil respiration of soil respiration turn up in summer and the lowest turn up in winter. The annual soil respiration fluxes of 22-year, 35-year, 65-year spruce plantation and natural spruce forest are 1004.24, 792.08, 975.3, 1070.2 g.C.m-2.year-1 respectively. The annual soil respiration fluxes of spruce plantations decrease at the beginning of restoration process (year 22 to year 35) , then turn up to increase in later restoration process (year 35 to natural forest). The fluxes of soil autotrophic respiration of 22-year, 35-year, 65-year spruce plantation and natural spruce forest are 340.79±36.43, 253.38±9.37, 350.11±15.69, 357.27±11.88 g.C.m-2year-1 respectively. The fluxes of soil heterotrophic respiration of 22-year, 35-year, 65-year spruce plantation and natural spruce forest are 656.69±17.22, 543.92±3.35, 607.62±29.93, 712.97±17.30 g.C.m-2year-1 respectively. The orders of fluxes heterotrophic and autotrophic respiration in the four forests from high to low are natural spruce forest, 22-year, 65-year, 35-year spruce plantation. Soil total organic carbon (TOC) at 0-10 cm, 10-20 cm, 20-30 cm all have similar variation regular that TOC decrease from 22-year to 65-year spruce plantation and increase from 65-year spruce plantation to natural spruce forest. Soil microbe carbon (MBC) has the same variation regular as TOC. TOC has best significant correlation with fluxes of soil heterotrophic respiration and significant correlation with fluxes of soil total respiration. MBC has significant correlation with fluxes of soil heterotrophic respiration and total soil respiration. Both of TOC and MBC has insignificant correlation with fluxes of soil autotrophic respiration. TOC and MBC may directly influence soil heterotrophic respiration then influence soil total respiration indirectly. The soil respiration temperature sensitivity (Q10) of 22-year, 35-year, 65-year spruce plantation and natural spruce forest are 4.59, 6.54, 4.77, 3.18 in nor-growing season respectively and 4.17, 4.66, 3.11, 2.74 in growing season respectively. Q10 values of nor-growing season are significant higher than that of growing season. Q10 values decrease at the forest restoration process. |
| 语种 | 中文 |
| 学科主题 | 生态学 |
| 公开日期 | 2010-11-24 |
| 页码 | 63 |
| 内容类型 | 学位论文 |
| 源URL | [http://210.75.237.14/handle/351003/238]  |
| 专题 | 成都生物研究所_生态研究 |
| 推荐引用方式 GB/T 7714 | 周非飞. 青藏高原东缘亚高山针叶林人工恢复过程中的土壤呼吸研究[D]. 2009. |
| 个性服务 |
| 查看访问统计 |
| 相关权益政策 |
| 暂无数据 |
| 收藏/分享 |
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。
修改评论