广东红树林土壤有机碳分布特征及其影响因素研究

发布时间：2018-07-02 11:58

本文选题：红树林湿地 + 土壤有机碳含量　；参考：《广西师范学院》2015年硕士论文

【摘要】：红树林湿地具有较高的初级生产力和固碳能力,在全球碳循环和碳平衡中发挥着至关重要的作用。红树林湿地土壤因缺氧环境而积累大量有机碳,形成一个巨大的碳库,参与全球碳循环。本研究将广东省红树林湿地分为粤东、珠江口、粤西、雷州半岛4个调查片区,对各片区内红树林生长状况和生境特点进行调查,按10cm一层采集30cm深土壤样品,测定土壤有机碳含量以及土壤含水量、土壤容重、土壤孔隙度和土壤p H值等土壤理化指标,计算土壤有机碳密度和土壤碳储量,运用Excel和SPSS软件进行数据处理,对比不同片区土壤有机碳含量,分析其与各土壤指标的相关性,探讨水质、土壤、植被、气候和人为因素对红树林土壤有机碳的影响。本文研究结果表明:1、广东省红树林湿地30cm深土层内,土壤有机碳含量介于4.3~68.7g/kg,平均值为16.48g/kg,变异系数为0.71,属高度变异。不同片区的红树林湿地土壤有机碳含量差异明显,最高为粤东,其次为珠江口和粤西,最低为雷州半岛,平均值分别为:26.42g/kg、24.89g/kg、16.32g/kg和10.93g/kg,从广东东部到南部有逐渐降低的趋势。2、从垂直剖面上看,10~20cm土层的土壤有机碳含量高于0~10cm土层和20~30cm土层,平均值自上而下分别为19.55 g/kg、19.57 g/kg和17.62 g/kg,各土层土壤有机碳含量差异不明显。3、广东省红树林湿地30cm深土壤有机碳密度范围在0.97~13.18 kg/m2,平均值为4.22 kg/m2,变异系数为0.50,属中度变异。广东红树林湿地土壤有机碳储量约为1.27×104~4.46×104t(30cm)。4、土壤有机碳含量与土壤容重和土壤pH值呈极显著负相关(P0.01),与土壤含水量呈显著正相关(P0.05),与土壤孔隙度的关系在在粤东和珠江口地区呈极显著的正相关(P0.01),在粤西地区呈显著正相关(P0.05),在雷州半岛相关性不明显(P0.05)。各土壤理化指标对土壤有机碳含量影响程度的大小顺序为:土壤含水量土壤容重土壤孔隙度土壤pH值。5、以珠江口地区红树林湿地为例,不同群落类型土壤有机碳含量大小依次为:秋茄群落白骨壤群落老鼠|群落桐花树群落无瓣海桑群落。土壤有机碳含量分别与树高、盖度的关系不明显,植被对土壤有机碳的影响应是各种植被指标如植被类型、树高、盖度、胸径、结构特征等综合作用的结果。6、人为因素对红树林干扰剧烈,主要表现为红树林内采挖和放牧、沿海开发建设、养殖塘废水和生活垃圾及污水排放等。另外,互花米草蔓延生长迅速,无瓣海桑有扩散现象。这些因素影响红树林的分布从而影响红树林土壤有机碳的固定。
[Abstract]:Mangrove wetlands have high primary productivity and carbon sequestration capacity and play an important role in the global carbon cycle and carbon balance. Mangrove wetland soil accumulates a large amount of organic carbon because of hypoxia environment, forming a huge carbon pool and participating in the global carbon cycle. In this study, the mangrove wetland in Guangdong Province was divided into four investigation areas: eastern Guangdong, Pearl River Estuary, West Guangdong and Leizhou Peninsula. The mangrove growth and habitat characteristics in each region were investigated, and 30cm deep soil samples were collected according to the first layer of 10cm. Soil organic carbon content, soil water content, soil bulk density, soil porosity and soil pH were measured to calculate soil organic carbon density and soil carbon reserves. Excel and SPSS software were used to process the data. The correlation between soil organic carbon content and soil index was analyzed, and the effects of water quality, soil, vegetation, climate and human factors on soil organic carbon in mangrove forest were discussed. The results show that in the 30cm deep soil layer of the mangrove wetland in Guangdong Province, the soil organic carbon content is between 4.3 ~ 68.7 g / kg, the average value is 16.48 g / kg, and the coefficient of variation is 0.71, which is highly variable. The soil organic carbon content of mangrove wetland in different areas is obviously different, the highest is eastern Guangdong, the second is Pearl River Estuary and western Guangdong, the lowest is Leizhou Peninsula. The average values were: 26.42 g / kg, 24.89 g / kg, 16.32 g / kg and 10.93 g / kg, respectively. There was a decreasing trend from east to south of Guangdong Province. The soil organic carbon content of 1010 ~ 20cm soil layer was higher than that of 0~10cm soil layer and 20~30cm soil layer from vertical profile. The average values from top to bottom were 19.55 g / kg ~ 19.57 g/kg and 17.62 g / kg ~ (-1) 路kg ~ (-1), respectively. There was no significant difference in soil organic carbon content among different soil layers. The soil organic carbon density of 30cm deep soil in Guangdong mangrove wetland ranged from 0.97 to 13.18 kg / m ~ (2), the average value was 4.22 kg / m ~ (2), and the coefficient of variation was 0.50, which was a moderate variation. The soil organic carbon storage of mangrove wetland in Guangdong is about 1.27 脳 10 ~ 4 ~ 4.46 脳 10 ~ (4) t (30cm). 4. The soil organic carbon content is negatively correlated with soil bulk density and soil pH value (P0.01), and positively correlated with soil water content (P0.05). The relationship between soil organic carbon content and soil porosity is found in eastern Guangdong and Zhujiang. There was a very significant positive correlation in Jiangkou area (P0.01), a significant positive correlation in western Guangdong (P0.05), and no significant correlation in Leizhou Peninsula (P0.05). The order of influence of soil physical and chemical indexes on soil organic carbon content is: soil water content, soil bulk density, soil porosity, soil pH value, and mangrove wetland in Pearl River estuary as an example. The order of soil organic carbon content of different community types was as follows: Amur community, white bone soil community, mouse community, Paulownia community, floral tree community, non-petal sea mulberry community. The relationship between soil organic carbon content and tree height and coverage is not obvious. The effect of vegetation on soil organic carbon should be a variety of vegetation indicators such as vegetation type, tree height, coverage, DBH. The result of the comprehensive action, such as structural characteristics, is that the mangroves are seriously disturbed by human factors, such as mangrove excavation and grazing, coastal development and construction, aquiculture pond wastewater, domestic refuse and sewage discharge, and so on. In addition, Spartina alterniflora spread rapidly, without petal sea mulberry spread phenomenon. These factors affect the distribution of mangroves and thus affect the soil organic carbon fixation of mangroves.
【学位授予单位】：广西师范学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S714.2

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