晋西黄土区退耕16-20年间不同林地土壤理化性质和水文功能研究

发布时间：2018-06-16 04:44

本文选题：晋西黄土区 + 土壤理化性质　；参考：《北京林业大学》2015年硕士论文

【摘要】：为探究晋西黄土区典型退耕林地间土壤理化性质和水文功能的差异,选取山西吉县蔡家川流域1994年退耕的油松(Pinus tabulaeformis, P)人工林、刺槐(Robinia pseudoacacia, R)人工林、油松×刺槐人工混交林(Pinus tabulaeformis×Robinia pseudoacacia, P×R) 3种人工退耕林地和坡耕地封禁封育形成的次生林(Secondary forest, SF)4种典型林分为研究对象,同时以耕地(CK)作为对照,通过退耕16-20年间不同林地的外业调查,室内测定和分析比较。结果表明：(1)不同林地土壤理化性质方面,随着退耕年限的积累,土壤密度呈现逐渐减小的趋势,土壤孔隙度、饱和导水率、有机质含量呈现逐年增加的趋势,但逐年变化差异不显著,除土壤颗粒组成外,退耕19年和20年较退耕16年则有显著提高；lm厚度土层土壤有机质,土壤孔隙度,根系含量和土壤饱和导水率：次生林油松x刺槐混交林刺槐人工林油松人工林耕地。土壤根系越多,土壤有机质含量越高,土壤密度越小,土壤饱和导水率越大,土壤总孔隙度和毛管孔隙度越大。(2)3种人工退耕林地和次生林水文功能方面,枯落物蓄积量呈现逐年增加的趋势,最大和有效持水量次生林混交林刺槐林油松林,且4种林分之间差异显著。不同退耕林地和耕地lm厚度土层的饱和含水量和毛管持水量：次生林混交林油松林刺槐林耕地。综合枯落物层和土壤层持水能力评价林地最大持水能力和有效持水能力发现,各林地的最大和有效持水能力表现为次生林混交林刺槐林油松林耕地,且土壤层的持水能力是林地水文功能的主要方面。通过研究地区退耕16-20年间不同林地的物理性质和水文功能的比较发现,林地较耕地有显著改善和提高,退耕效果最好的是次生林,其次是混交林,最差为人工纯林。表明次生林宜作为该地区退耕植被恢复的主要参考。
[Abstract]:In order to investigate the difference of soil physical and chemical properties and hydrological function among typical returning forest land in Shanxi Province, the Pinus tabulaeformis (P) plantation and Robinia pseudoacacia (R) plantation were selected from Cai Jiachuan Basin, Ji County, Shanxi Province in 1994. Pinus tabulaeformis 脳 Robinia pseudoacacacia (P 脳 R) three typical secondary forest forests, secondary forestand SFN, which were closed off from sloping farmland, were divided into study objects, and cultivated land CK was taken as control. Through field investigation of different forest land in 16-20 years, indoor measurement and comparison were made. The results showed that soil density decreased gradually with the accumulation of returning years, soil porosity, saturated water conductivity and organic matter content increased year by year. However, there was no significant difference in the change of soil organic matter and soil porosity between 19 years and 20 years after returning to tillage for 19 and 20 years. Root content and soil saturated water conductivity: secondary forest Pinus tabulaeformis x Robinia pseudoacacia mixed forest Pinus tabulaeformis plantation cultivated land. The more soil roots, the higher the content of soil organic matter, the smaller the soil density, the greater the saturated water conductivity of soil, the greater the total porosity and capillary porosity of soil. Litter volume increased year by year, the maximum and effective water holding capacity of secondary forest mixed forest Robinia pseudoacacia forest, Pinus tabulaeformis forest, and there were significant differences among the four forest types. Saturated water content and capillary water holding capacity of soil layer with different depth of lm in different returning forest land and cultivated land: secondary mixed forest, Pinus tabulaeformis forest, Robinia pseudoacacia forest cultivated land. The maximum and effective water holding capacity of forest land was evaluated by synthesizing the water holding capacity of litter layer and soil layer. It was found that the maximum and effective water holding capacity of each forest was the cultivated land of Pinus tabulaeformis plantation in mixed forest of secondary forest and Robinia pseudoacacia forest. The water holding capacity of soil layer is the main aspect of hydrological function of forest land. By comparing the physical properties and hydrological functions of different woodlands in the study area during 16-20 years, it was found that the forest land was significantly improved and improved compared with the cultivated land, the best effect was secondary forest, the second was mixed forest, and the worst was artificial pure forest. It is suggested that secondary forest should be used as the main reference for vegetation restoration in this area.
【学位授予单位】：北京林业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S714

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