洞庭湖区两种森林类型水土保持功能研究

发布时间：2018-07-04 18:21

本文选题：水源涵养 + 保育土壤　；参考：《中南林业科技大学》2015年硕士论文

【摘要】：洞庭湖位于湖南省北部,是我国重要的湖泊生态功能区。近年来,人类不合理活动导致湖泊的面积逐年缩小,湿地功能和生态环境发生了较大的变化。三峡水利枢纽的建成,对于长江与洞庭湖的关系是一个巨大的改变,江湖关系由此进入了一个全新的阶段。本文以洞庭湖区两种森林类型为研究对象,结合洞庭湖区林分类型的实际特点,采用野外定位观测和室内分析方法,对洞庭湖区两种森林类型的水土保持功能进行研究,并运用主成分分析法对该区域森林水土保持功能进行了综合评价。结果表明：(1)洞庭湖区森林植被对水文过程起到了一定的调节作用,对土壤起到了保育作用。在水源涵养方面,不同林地的灌草层、枯落物层持水量与其贮量呈正相关关系,灌草层持水量在0.78～2.70 t·hm-2之间；枯落物层持水量在3.83～5.38t·hm-2之间；林地土壤0-45cm范围内最大蓄水量为1851.40～2398.83t·hmz,0～45cm土壤有效蓄水量范围为472.37 t·hm2-606.11 t·hm-2。土壤有效蓄水量平均值大小为杨树林(2206.50t·hm-2)杉木林(2235.91 t·hm-2)。相对于杨树林而言,杉木林的土壤蓄水能力较强。在保育土壤方面,不同林地土壤侵蚀量在2.03～4.13t·hm-2·a-1之间,林地保持土壤量为33.45～35.55 t·hm-2·a-1.因森林植被对林地土壤的保护作用,林地每年减少流失的有机质含量为539.04～658.37kg·hm-2,全N 26.09～31.06kg·hm-2全P 16～23.07kg·hm-2,全K72.06～92.67kg·hm-2。(2)林地土壤0～45cm范围内,土壤有机质、土壤全N、全P含量随着土壤深度的增大而减小,土壤全K含量随着土壤深度的增大而增大。(3)运用主成分分析方法,对不同林地水土保持功能进行综合评价表明：相对于杨树林而言,杉木林的水土保持功能较强。具体表现为：澧县杉木林2澧县杉木林1岳阳县杉木林1汉寿杨树林1岳阳县杉木林2沅江杨树林1沅江杨树林2汉寿杨树林2。以上研究结果为洞庭湖区水土保持功能研究提供了基础参考数据,对该区森林植被的建设和保护起到一定理论指导作用。
[Abstract]:Dongting Lake, located in the north of Hunan Province, is an important ecological functional area of lakes in China. In recent years, human unreasonable activities have led to the reduction of lake area year by year, and great changes have taken place in wetland function and ecological environment. The completion of the three Gorges Project is a great change to the relationship between the Yangtze River and the Dongting Lake, and the relationship between the Yangtze River and the Dongting Lake has entered a new stage. In this paper, the soil and water conservation functions of two forest types in Dongting Lake region were studied by using field positioning observation and indoor analysis method, combining with the actual characteristics of forest types in Dongting Lake region. The function of forest soil and water conservation in this area was evaluated by principal component analysis. The results show that: (1) the forest vegetation in Dongting Lake region plays a role in regulating the hydrological process and protecting the soil. In terms of water conservation, there was a positive correlation between the capacity of litter layer and its storage in different forest land, the water holding capacity of shrub layer was between 0.78 ~ 2.70 t / hm-2, and that of litter layer was between 3.83 ~ 5.38 t / hm-2. The maximum water storage capacity in the 0-45cm range of forest soil was 472.37 t hm2-606.11 t hm-2, which was 2398.83 t 路hmz0 ~ (-1) t 路h ~ (-1) ~ (-1) ~ (-1) ~ (-1) ~ (-1) ~ (-1) ~ (-1). The average value of soil available water storage was 2235.91 t hm-2 in poplar forest (2206.50 t hm-2) and Chinese fir forest (2235.91 t hm-2). Compared with poplar forest, the soil water storage capacity of Chinese fir forest is stronger. In the aspect of soil conservation, the soil erosion amount of different forest land was between 2.03 ~ 4.13 t hm-2 a ~ (-1), and the soil amount of forest land was 33.45 ~ 35.55 t hm-2 a ~ (-1). Because of the protective effect of forest vegetation on forestland soil, the content of organic matter reduced by forest land every year is 539.04~658.37kg hm-2, total N 26.09~31.06kg hm-2 total P 16~23.07kg hm-2, total K72.06 ~ 92.67 kg hm-2. (2) soil organic matter in the range of 0~45cm in forestland soil. The content of total N and total P decreased with the increase of soil depth, and the total K content of soil increased with the increase of soil depth. (3) Principal component analysis (PCA) was used. The comprehensive evaluation of soil and water conservation function of different forest land showed that the soil and water conservation function of Chinese fir forest was stronger than that of poplar forest. The concrete manifestation is: Lixian Cunninghamia lanceolata forest 2 Lixian Cunninghamia lanceolata forest 1 Yueyang county Cunninghamia lanceolata forest 1 Hanshou poplar forest 1 Yueyang county Chinese fir forest 2 Yuanjiang poplar forest 1 Yuanjiang poplar forest 2 Hanshou poplar forest 2. The above results provide basic reference data for the study of soil and water conservation function in Dongting Lake area and play a certain theoretical guiding role in the construction and protection of forest vegetation in this area.
【学位授予单位】：中南林业科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S714.7

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