柚木人工林林下植被多样性和土壤理化性质的研究

发布时间：2018-05-17 15:22

本文选题：柚木人工林 + 林下植被　；参考：《中国林业科学研究院》2017年硕士论文

【摘要】：本研究以广东省揭阳市、云南河口、云南勐腊和海南省柚木人工林为对象,设立91个样地,通过调查样方的植被种名、株数、高度及盖度等,并采集0~20cm和20~40cm土壤进行理化性质分析,研究不同密度、林龄、坡位和区域的人工林林下植被及土壤理化性质及其二者的相关性,并以林下植被物种多样性指数及其土壤理化性质进行主成分分析来评价柚木人工林的立地质量,为柚木人工林可持续经营提供科学依据。通过野外调查和内业处理分析,得出以下主要结论:(1)广东揭阳不同林分密度柚木人工林调查结果表明:随着林分密度增加,林下植被Shannon-Wiener指数、Simpson优势度指数、丰富度指数和均匀度指数表现出先增加后减少的趋势;相同密度下,上层土土壤理化性质优于下层土,不同林分密度间柚木人工林土壤毛管孔隙度、非毛管孔隙度、速效K、速效P、全P、交换性酸和交换性Al等土壤理化性质指标差异性显著(P0.05);随着林分密度增大,土壤理化性质整体呈现出先改善后退化的变化过程;基于主成分分析结果得出适宜的林分密度(1 050株·hm-2)有利于保持较好的林下植被物种多样性和土壤理化性质。不同密度人工林的土壤毛管孔隙度和总孔隙度与林下植被物种多样性指数呈显著的负相关性,速效P对灌木物种多样性指数也有重要指示作用。(2)云南河口不同林龄柚木人工林调查结果表明:随着林龄的增加,灌木层Shannon-Wiener指数、Simpson优势度指数、均匀度指数、丰富度指数和草本层的均匀度指数、丰富度指数呈现出先增大后减小的趋势,且指数值都在20年时最大;土壤体积含水量、田间持水量、毛管孔隙度、总孔隙度和非毛管孔隙度等土壤物理性质指标整体变化趋势是先降低后增加,然后再下降的变化趋势,这一变化规律与土壤密度刚好相反;而全K、速效K、速效P、全N、有机质、交换性钙、上层交换性酸和阳离子交换量等化学性质指标先增大后减小;由主成分分析结果,不同林龄柚木人工林物种多样性和土壤理化性质综合得分由大到小依次是:20a(1.42)8a(0.54)13a(-0.42)26a(-0.47),说明柚木人工林在生长过程中,在20年生的时候林地立地质量较高。不同林龄柚木人工林的草本层Shanon-Wiener指数、丰富度指数与土壤总孔隙度、毛管孔隙度呈显著的正相关性,灌木层的Shanon-Wiener指数与毛管孔隙度、田间持水量、全P、交换性钙呈极显著的正相关性,灌木层Pielou均匀度指数和丰富度指数与毛管孔隙度、田间持水量、交换性钙呈显著的正相关性。(3)云南勐腊不同坡位柚木人工林调查结果表明:由上坡到下坡,其中草本层的Shannon-Wiener指数、Simpson优势度指数、均匀度指数和丰富度指数逐渐增加,灌木层的物种多样性指数则是表现出逐渐降低的趋势;从上坡到下坡过程中,土壤密度逐渐增大,田间持水量和毛孔隙度表现为逐渐下降的趋势,体积含水量、总孔隙度和非毛管孔隙度的值是表现为中坡上坡下坡,土壤养分表现为上层下层,整体养分比较:中坡优于上坡或者下坡;由主成分分析结果结合柚木生长情况可判断中下坡是柚木生长较为理想的立地条件。不同坡位柚木人工林的土壤全K与草本层Shanon-Wiener指数、Simpson优势度指数和丰富度指数呈显著的正相关性,速效P与Shanon-Wiener指数和丰富度指数呈显著的正相关性。(4)海南不同地点柚木人工林调查结果表明:三个地点的同一物种多样性指数皆表现出:灌木层草本层,总体来说三个地点的土壤物理性质三亚高峰和五指山毛阳高于三亚半岭水库,土壤的交换性酸、交换性Al、盐基饱和度、交换性镁、阳离子交换量和有效Fe的大小表现为:三亚高峰五指山毛阳三亚半岭水库,全P、速效P、全N、有机质的大小则是:三亚半岭水库五指山毛阳三亚高峰,交换性钙、上层全K和下层有效Zn的大小为:五指山毛阳三亚高峰三亚半岭水库;由主成分分析综合得分可知五指山毛阳地区是柚木生长较好的地点。不同区域柚木人工林的土壤全P与草本植被物种多样性指数呈极显著的负相关性,土壤密度、体积含水量和速效P对草本物种多样性指数也有重要指示作用。(5)不同省份柚木人工林林下植被调查表明,广东揭阳柚木林地植被合计59种植物,隶属于39科55属,云南河口合计66种植物,隶属于39科62属,云南勐腊合计65种植物,隶属于42科63属,海南的植被最为丰富,共出现87种植物,隶属于38科80属,人工林样地双子叶植物在植被中占主导地位,薇甘菊、铁芒箕、白茅草、蔓生莠竹、粽叶芦、刺篱木、山石榴等植物是柚木生长较差的指示植物,鸭跖草、火炭母、狗脊、华南毛厥和岭南山竹子等植被是柚木生长较好的指示植物;柚木人工林下植被具有较强的热带植被区系特征。不同区域柚木人工林的土壤全P与草本植被物种多样性指数呈极显著的负相关性,土壤密度、体积含水量和速效P对草本物种多样性指数也有重要指示作用。
[Abstract]:In this study, 91 plots were set up in Jieyang, Yunnan estuary, Yunnan estuary, Yunnan Mengla and Hainan province teak plantation. By investigating the name, number, height and coverage of the vegetation, the soil of 0~20cm and 20~40cm was collected to analyze the physical and chemical properties of the soil, and the vegetation and soil under the plantation of different density, forest age, slope position and area were studied. The physical and chemical properties of the soil and the correlation between the two and the principal component analysis of the species diversity index and the physical and chemical properties of the subforest vegetation are used to evaluate the site quality of the teak plantation and provide a scientific basis for the sustainable management of the teak plantation. Through field investigation and internal processing analysis, the following main conclusions are obtained: (1) Guangdong Jieyang does not The survey results of teak plantation in the same forest density showed that the Shannon-Wiener index, Simpson dominance index, richness index and evenness index of the undergrowth were increased first and then decreased with the increase of stand density; under the same density, the physical and chemical properties of the upper soil soil were superior to those of the lower soil and the teak plantation soil between different stand density. The soil physical and chemical properties of soil porosity, non capillary porosity, quick acting K, quick acting P, all P, exchangeable acid and exchangeable Al were significantly different (P0.05). As the stand density increased, the soil physical and chemical properties were first improved and then degraded, and the suitable stand density (1050 plant. Hm-2) was obtained based on the results of principal component analysis. It is beneficial to maintain better species diversity and soil physical and chemical properties of understory vegetation. The soil capillary porosity and total porosity of different density plantations have significant negative correlation with the species diversity index of undergrowth vegetation, and the quick acting P also has important instructions for the shrub species diversity index. (2) the different forest age pomelo woodwork in the Yunnan Estuary The results showed that with the increase of forest age, the Shannon-Wiener index, Simpson dominance index, evenness index, richness index, and the evenness index of the herb layer, the richness index increased first and then decreased, and the index value was the largest in 20 years, the volume of soil water, the field water holding capacity, the capillary porosity, and the total soil volume. The overall change trend of soil physical properties, such as porosity and non capillary porosity, is first decreasing and then decreasing, and the change trend is just the opposite of soil density, and the chemical properties of all K, quick acting K, quick acting P, all N, organic matter, exchangeable calcium, upper interchanging acid and cation exchange rate are increased first. According to the results of principal component analysis, the overall score of species diversity and soil physical and chemical properties of different forest age pomelo trees from large to small were 20A (1.42) 8A (0.54) 13A (-0.42) 26a (-0.47), indicating that in the growth process of teak plantation, the forest site quality was higher when 20 years old, and the grass layer Shanon-W of different forest age pomelo wood human forest The iener index, the richness index has a significant positive correlation with the total soil porosity and capillary porosity, and the Shanon-Wiener index of the shrub layer has a very significant positive correlation with the capillary porosity, the field water holding capacity, the total P, the exchangeable calcium, and the Pielou evenness index and the richness index of the shrub layer and the capillary porosity, the field water holding capacity and the exchangeable calcium. Significant positive correlation. (3) the survey results of teak plantation in different slope positions in Mengla, Yunnan showed that from upslope to downhill, the Shannon-Wiener index, Simpson dominance index, evenness index and richness index increased gradually from upslope to downhill, and the species diversity index of shrub layer was gradually decreasing; from upslope to downhill In the process, the soil density increased gradually, the field water holding capacity and pore gap degree showed a gradual decline trend, the volume water content, the total porosity and the non capillary porosity were shown as the upper slope of the middle slope, the soil nutrient was upper lower, the overall nutrient was compared: the middle slope was superior to the upper slope or the downslope; the result of the principal component analysis combined with the grapefruit. The growth conditions of wood can be judged to be the ideal site for the growth of teak growth. The total K of the soil of teak plantation in different slope positions has a significant positive correlation with the Shanon-Wiener index of herbaceous layer, the index of Simpson dominance and the richness index, and there is a significant positive correlation between the available P and the Shanon-Wiener index and the richness index. (4) Hainan does not. The survey results of teak plantation in the same location showed that the species diversity index of the three sites showed: the shrub layer herbaceous layer, the soil physical properties of the three locations, the Sanya peak and the Five Fingers Group Mao Yang higher than the Sanya semi Ridge Reservoir, the exchangeable acid, the exchangeable Al, the salt base saturation, the exchangeable magnesium and the cation exchange amount. And the size of effective Fe is: Sanya peak Five Fingers Group Mao Yang Sanya semi Ridge Reservoir, full P, quick acting P, all N, the size of organic matter is: Sanya semi Ridge Reservoir Five Fingers Group Mao Yang Sanya peak, exchangeable calcium, upper level all K and lower effective Zn size: Five Fingers Group Mao Yangsan sub peak Sanya semi Ridge Reservoir; the main component analysis comprehensive score can There is a very significant negative correlation between the total P of the teak plantation in different regions and the species diversity index of herbaceous vegetation in different regions. The soil density, volume water content and quick acting P also have important indicators for the herbaceous species diversity index. (5) the understory vegetation of teak plantation in different provinces. It is found that 59 species of vegetation in Jieyang teak forest in Jieyang, Guangdong, belong to 55 genera of 39 families, 66 species belonging to 39 families and 62 genera in Yunnan estuary, and 65 species in Mengla, Yunnan, belonging to 42 families and 63 genera, and 87 plants in Hainan, belonging to 38 families, and plantation like dicotyledonous plants dominated by vegetation. Status, chrysanthemum, iron awl skip, citrus grass, vines atrazine, rice dump, spiny hedgerow, pomegranate and pomegranate are indicative plants for teak growth, and the vegetation of canelwood, charcoal, Kolon, Southern China and Lingnan mountain is the better indicator plant for teak growth, and the subvegetation of teak woodwork has a strong tropical flora characteristic. The total soil P of the regional teak plantation has a very significant negative correlation with the species diversity index of herbaceous vegetation, and the soil density, volume water content and quick acting P also have an important indicator for the herbaceous species diversity index.
【学位授予单位】：中国林业科学研究院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S718.5

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