贡嘎山东坡峨眉冷杉林碳贮量与碳平衡
文献类型：学位论文
| 作者 | 陈有超
|
| 学位类别 | 硕士 |
| 答辩日期 | 2013 |
| 授予单位 | 中国科学院研究生院 |
| 授予地点 | 北京 |
| 导师 | 罗辑 |
| 关键词 | 峨眉冷杉 碳贮量 碳平衡 |
| 其他题名 | Carbon Storage and Balance in Abies fabri forest on east slope of Gongga Mountain |
| 学位专业 | 环境工程 |
| 中文摘要 | 峨眉冷杉是四川特有的森林树种。天然林分布面积约23万hm2，蓄积量近8000万m3。贡嘎山位于青藏高原东缘，该区域地球各圈层相互作用剧烈，对全球气候变化也极为敏感。鉴于森林生态系统在全球碳循环中的重要作用，本研究以贡嘎山东坡峨眉冷杉林这一典型生态系统为对象，分析贡嘎山东坡峨眉冷杉成熟林、中龄林生态系统碳现存量及各个碳库间的碳流动，对比成熟林和中龄林的碳汇功能，补充和完善贡嘎山峨眉冷杉林碳循环研究，为全球变化背景下碳循环研究提供基础数据，同时为冷杉天然林保护和可持续发展提供决策依据。论文主要研究结果如下： （1）成熟林冷杉各器官碳素含量变化范围为49.4%~53.4%，中龄林冷杉各器官碳素含量变化范围为49.3%~50.9%，冷杉各器官间的碳素含量存在细微差别；成熟林和中龄林中针叶树的各器官的碳素含量均显著大于阔叶树相应器官的碳素含量（成熟林的叶子除外）。成熟林灌木层的碳素含量变化范围为42.6%~46.1%，中龄林灌木层的碳素含量变化范围为44.1%~47.0%。成熟林和中龄林林下植被层各器官的碳素均含量明显低于乔木层中相应器官的碳素含量。 （2）成熟林土层碳素含量的变化范围为2.28%~8.73%，中龄林土层碳素含量的变化范围为0.78%~3.92%。两个林分的土壤碳素含量在垂直分布上均表现为随土壤深度的增加而降低的趋势。不同发育阶段的峨眉冷杉林土壤含碳率存在差异，表现为成熟林土壤各层的碳素含量都明显高于中龄林土对应土层的碳素含量。无论是在峨眉冷杉成熟林还是中龄林，土壤各层次有机碳含量与土壤全氮含量之间均存在显著的正相关性，而土壤pH值之间呈显著的负相关性。 （3）成熟林的植被生物量为590.6 t/hm2，是中龄林植被生物量的2.2倍，成熟林植被层碳贮量为288.4 t C/hm2，是中龄林植被碳贮量的2.2倍。成熟林凋落物和枯倒木的碳贮量分别是1.9 t C/ hm2 和3.5 t C/ hm2，中龄林凋落物和枯倒木量分别为1.4 t C/hm2和8.7 t C/ hm2。贡嘎山东坡峨眉冷杉成熟林的土壤碳贮量为291.8 t C/ hm2，中龄林土壤碳贮量为63.8 t C/ hm2。综合以上结果可得，峨眉冷杉林成熟林生态系统的碳贮量为579.4 t/hm2，中龄林生态系统的碳贮量为197.4 t/hm2。成熟林生态系统中各组成部分的碳素贮量按大小顺序排列为：土壤层>植被层>死地被物层（凋落物和枯倒木）；中龄林生态系统中各组分的碳贮量大小顺序为：植被层>土壤层>死地被物层。 （4）峨眉冷杉成熟林和中龄林土壤呼吸速率均存在明显的季节变异。成熟林土壤呼吸率的季节变差系数CV为50.6%，中龄林土壤呼吸率的季节变差系数为48.5%；成熟林土壤呼吸速率与5cm土壤温度之间的关系为Rs=1.27e0.115ST；中龄林土壤呼吸速率与5cm土壤温度之间的关系为Rs=0.9e0.097ST。基于土壤温度的指数模型可以分别解释成熟林和中龄林土壤呼吸速率66%和60%的变异。最终计算出成熟林土壤呼吸全年排放量为10.3 t C/ hm2，中龄林土壤呼吸全年排放量为6.5 t C/ hm2，峨眉冷杉成熟林土壤呼吸的年总排放量比中龄林的高出58.6%。按照成熟林和中龄林非根呼吸占总呼吸量的比例（成熟林取0.5，中龄林取0.58），可计算出峨眉冷杉成熟林非根土壤呼吸量为5.2 t C/hm2，中龄林土壤非根呼吸量为3.8 t C/hm2。 （5）峨眉冷杉成熟林和中龄林凋落物在各月分布很不均匀，峨眉冷杉中龄林月凋落物量变化呈双峰型，而成熟林月凋落物量变化呈单峰型。成熟林和中龄林的凋落物均以针叶为主，并且针叶的月凋落动态也和凋落物总量的月动态一致。峨眉冷杉中龄林年凋落物量为3.1 t/ hm2。凋落物中枯叶（针叶和阔叶）量占有较大比例，峨眉冷杉成熟林的年凋落物量为3.6 t/ hm2，其中针叶占绝大部分。根据凋落物各组分碳含量，最终计算出中龄林凋落物碳素的年归还量为1.5 t C/ hm2，成熟林凋落物碳素的年归还量为1.8 t C/ hm2。 由于贡嘎山 地区常年温度较低，凋落物分解速慢因此本文利用由于贡嘎山 地区常年温度较低，凋落物分解速慢因此本文利用由于贡嘎山 地区常年温度较低，凋落物分解速慢因此本文利用站峨眉冷杉林区（ 演替）的多年2007 -2011 2011年）定位观测数据，对 峨眉冷杉林凋落 物分解进行一个初步的研究。结果显示，随着时间推移峨眉冷杉林凋落 物分解进行一个初步的研究。结果显示，随着时间推移峨眉冷杉林凋落 物分解进行一个初步的研究。结果显示，随着时间推移峨眉冷杉林凋落 物分解进行一个初步的研究。结果显示，随着时间推移物的干质重愈来小，即其损失量随时间 增加而大。碳素含也着物的干质重愈来小，即其损失量随时间 增加而大。碳素含也着物的干质重愈来小，即其损失量随时间 增加而大。碳素含也着推移而逐渐减小，凋落物中碳素的释放速率为阔叶 推移而逐渐减小，凋落物中碳素的释放速率为阔叶 >针叶 >枯枝。阔叶 枯枝。阔叶 凋落物 干质的半衰期为 3.8 3.8年，周转期为 ，周转期为 16.4 16.4年，碳素的半衰期为 3.0 3.0年，周转期为 ，周转期为 12.8 12.8年；针叶凋落物干质的半衰期为 ；针叶凋落物干质的半衰期为 7.3 7.3年，周转期为 ，周转期为 ，周转期为 30.4 30.4年，碳素的半衰期为 ，碳素的半衰期为 5.3年，周转期为 ，周转期为 22.8 22.8年； 枯枝凋落物干质的半衰期为 枯枝凋落物干质的半衰期为 8.6 8.6年，周转期为 ，周转期为 37.3 37.3年， 碳素的半衰期为 6.5 6.5年，周转期为 ，周转期为 28.3 28.3年。凋落物中碳素的释放规律与总干质 年。凋落物中碳素的释放规律与总干质 年。凋落物中碳素的释放规律与总干质 的分解速度并不完全一致。结合凋落物量数据，最终计算出演替林 的分解速度并不完全一致。结合凋落物量数据，最终计算出演替林 的分解速度并不完全一致。结合凋落物量数据，最终计算出演替林 每年通过阔叶 、 针叶和枯枝 经分解后 当年释放 的碳素量 分别为 1.55 1.55 kg/hm 2、48.57 48.57 kg /hm 2和 9.86 9.86 kg/hm 2，凋落物各组分在解过程中碳素的 总年 释放量约为 59.98 59.98 kg /hm 2，占凋落 时碳素量的 4.67 4.67 %。结合成熟林和中龄年凋落物数据，按照同样的方法可计 。结合成熟林和中龄年凋落物数据，按照同样的方法可计 。结合成熟林和中龄年凋落物数据，按照同样的方法可计 。结合成熟林和中龄年凋落物数据，按照同样的方法可计 算出峨眉冷杉成熟林和中 龄年凋落物（主要取阔叶、针枯枝）分解过程算出峨眉冷杉成熟林和中 龄年凋落物（主要取阔叶、针枯枝）分解过程算出峨眉冷杉成熟林和中 龄年凋落物（主要取阔叶、针枯枝）分解过程算出峨眉冷杉成熟林和中 龄年凋落物（主要取阔叶、针枯枝）分解过程的碳素释放量为 79.27 79.27 kg/hm 2和 65.54 65.54 kg/hm 2。 （6）根据 碳平衡计算公式 可得 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 ，峨眉冷杉成熟林碳素的净吸 存量为 +5.3+5.3 +5.3 t C/hmC/hm 2，中龄林的碳素净吸存量为 +4.5+4.5 +4.5 t C/hmt C/hmt C/hmt C/hm 2，成熟林和中龄均表现为 “碳汇 ”。 |
| 英文摘要 | Abies fabri is endemic tree species in Sicuan province, China. Distribution area of natural Abies fabri forest is about 230,000 hm2, with a volume of 80 million m3. Gongga Mountain, located at the east slope of Qinghai-Tibet plateau, is a region characterize with the mutual effects among various earth spheres, which is also extremely sensitive to global climate change. In view of important role of forest system in the global carbon cycle, we carried out the study in Abies fabri forest in Gongga Mountain. In this study, we analyzed the carbon storage and carbon flow of mature Abies fabri forest and middle-aged Abies fabri forest in east slope of Gongga Mountain, and compared the carbon sink function between mature and middle-aged Abies fabri forest. Our result will enhance Abies fabri forest carbon cycle research, and provide basic data for carbon cycle research under the background of global change. The main results of the research are as follows: (1) Carbon content ranged from 49.4% to 53.4% and 49.3% to 50.9% among organs of Abies fabri in mature forest and middle-aged forest, respectively. Subtle differences can be detected among organs in Abies fabri. The carbon content of organs of Abies fabri (except leaf in mature forest) were significantly greater than the corresponding organ carbon content of broad-leaved tree in mature and middle-aged forest. Carbon content of shrub layers ranged from 42.6% to 46.1% in mature forest, and 44.1% to 47.0% in middle-aged forest. The carbon content of organs of undergrowth vegetation were lower than those in tree layer. (2) The soil organic carbon content ranged from 2.28% to 8.73% in mature forest, and 0.78% to 3.92% in middle-aged forest. In both of the forests, soil organic carbon content decreased as the depth increased. The carbon content of each soil layer in mature forest were higher than the corresponding soil layer car content in middle-aged forest. Whether in the mature Abies fabri forest or middle-aged forest, soil organic carbon content positively correlated with soil total nitrogen content, and negatively correlated with soil pH value. (3) Vegetation biomass of mature Abies fabri forest was 590.6 t/hm2, 120% larger than that of middle-aged forest. Vegetation carbon storage was 274.4 t C/ hm2 in mature forest, 120% larger than that of middle-aged forest. Carbon storage of litter and fallen dead wood was 1.9 t C/ hm2 and 3.5 t C/ hm2 in mature forest, and 1.4 t C/hm2 and 8.7 t C/ hm2 in middle-aged forest. Soil carbon storage was 291.8 t C/ hm2 in mature forest and 63.8 t C/ hm2 in middle-aged forest, respectively. Based on the results above, carbon storage of mature Abies fabri ecosystem was 579.4 t/hm2, and carbon storage of middle-aged Abies fabri ecosystem was 197.4 t/hm2. The order of carbon storage in each component of mature forest can be ranked as soil >vegetation > litter floor. The order of carbon storage in each component of middle-aged forest can be ranked as vegetation > soil >litter floor. (4) There were substantial seasonal variation in soil CO2 emission for both mature and middle-aged forest. The seasonal coefficient of variation (CV) was 50.6% in mature forest and 48.5% in middle-aged forest. The relationship between soil CO2 emission and soil temporal at 5cm depth can be described as Rs=1.27e0.115ST in mature forest and Rs=0.9e0.097ST in middle-aged forest. The model based on soil temperature can explain 66% seasonal variation in mature forest and 60% seasonal variation in middle-aged forest, respectively. The annual soil CO2 emission was 10.3 t C/ hm2 and 6.5 t C/ hm2 in mature and middle-aged forest, respectively. According to the proportion of non-root soil respiration in mature (0.5) and middle-aged forest (0.58), we calculated non-root soli respiration was 5.2 t C/ hm2 and 3.8 t C/ hm2 in mature forest and middle-aged forest, respectively. (5) Monthly litter biomass was not uniform in Abies fabri forest. The monthly variation of litter showed a single-peak shape in middle-aged forest, while double-peak shape in mature forest. Litter in the two forest is mainly needle leaves. The litter biomass was 3.1 t/ hm2 in middle-aged, most of which is leaf (needle and broad leaf ), and and 3.6 t/ hm2 in mature forest, most of which is needle leaf. The annual return of carbon through litter is 1.5 t C/ hm2 for middle-aged forest and 1.8 t C/ hm2 for mature forest, respectively. Due to the low temperature in Gongga Mountain area, the litter decomposition rate was relatively slow in this region. So in this research, we made a preliminary study on Abies fabri forest litter decomposition, using a long-term (2007-2011) observation data in a young forest in Gongga Mountain. The resuts showed that, the dry matter, as well as carbon content of litter decreased with the passage of time. The release rate of carbon can be ranked as broad-leaf >needle leaf > dead-branch. The half-life period and turnover period of dry matter was 3.8 years and 16.4 years for broad-leaf, 7.3 years and 30.4 years for needle leaf, 8.6 years and 37.3 years for dead-branch, respectively. The The half-life period and turnover period of carbon was 3.0 years and 12.8 years for broad-leaf, 5.3 years and 22.8 years for needle leaf, 6.5 years and 28.3 years for dead-branch, respectively. The release rate of carbon and dry matter were not the same for litter. The carbon released for broad-leaf, needle leaf and dead-branch was 1.55 kg/hm2、48.57 kg/hm2 and 9.86 kg/hm2, respectively. The total carbon released for litter was 59.98 kg/hm2, which is 4.67% of initial carbon amount in litter. In the same way, we calculated the annual carbon release from litter mature and middle-aged forest was 79.27 kg/hm2 and 65.54 kg/hm2. (6) According to the formula of carbon balance, we calculated the net carbon sequestration for mature and middle-aged forest. The value was +5.3 t C/hm2 and +4.5 t C/hm2 for for mature and middle-aged forest, respectively. Mature Abies fabri and middle-aged Abies fabri are both “carbon sink”. |
| 语种 | 中文 |
| 公开日期 | 2014-07-05 |
| 源URL | [http://ir.imde.ac.cn/handle/131551/6979]  |
| 专题 | 成都山地灾害与环境研究所_山地表生过程与生态调控重点实验室 |
| 推荐引用方式 GB/T 7714 | 陈有超. 贡嘎山东坡峨眉冷杉林碳贮量与碳平衡[D]. 北京. 中国科学院研究生院. 2013. |
入库方式： OAI收割
来源：成都山地灾害与环境研究所
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