喀斯特地区3种林分土壤养分分布特征研究

发布时间：2018-04-15 10:25

  本文选题：喀斯特 + 天然林　； 参考：《中南林业科技大学》2017年硕士论文

【摘要】：林分土壤养分能为植物生长发育提供所需要的营养和环境条件,适宜的土壤养分是培育树木适产、优良的前提条件。然而近年来,过分追求经济利益和不科学的管理经营方式,导致林分的质量明显下降。研究不同林分土壤的养分状况可为林分的经营管理和可持续性发展提供科学依据。本文以贵州喀斯特地区马尾松人工林、马尾松天然林、湿地松人工林3种林分为研究对象,通过野外调查取样、室内实验与统计分析,对其土壤理化性质和养分特征进行了系统研究,结果表明:(1)马尾松人工林和天然林中不同层次土壤容重间具有差异显著性,3种林分土壤平均含水率在16.27%～25.54%,表层土中均是有机质含量最高,且与最深层土间表现出差异显著性,马尾松人工林的全N、全K和马尾松天然林的全K、全P均在不同层次土壤中有差异显著性,3种林分土壤大量元素N、P、K、Ca、Mg含量比较,全Mg含量所占比重较大,湿地松人工林土层中全Mg均值为0.83 g/kg,马尾松人工林为0.60g/kg,马尾松天然林为0.82g/kg,相对而言,土壤全P含量较低,仅有0.03～0.04g/kg,3种林分土壤层中速效元素含量均没有差异显著性,其中铵态N含量高于其它速效元素含量。湿地松和马尾松天然林中不同土层微量元素含量大小排序均不同,马尾松人工林中除最底层土壤外,其它层次土壤中微量元素含量大小排序一致,3种林分土层微量元素含量均是Fe最高,Cr最低。(2)不同林分同一土壤层次条件下,马尾松天然林土壤的容重、Pb元素、Mn元素含量均最高,而有机质含量明显低于其它两林分,3种林分的养分元素Mg、Fe、Cu、Zn、Ni、Mn含量均具有差异显著性,而铵态N、硝态N、速效P、速效K含量之间不存在差异显著性。3种林分土壤皆显弱酸性,土壤pH值幅度为4..3～4.6,土壤pH值与其它养分元素之间基本表现为负相关或显著负相关。(3)3种林分土壤中的全N与铵态N之间均呈现负相关性,微量元素之间相关性较好,基本表现为显著正相关(p0.05)或极显著正相关性(p0.01)。3林分土壤养分元素之间的相关性均不同,说明不同林分土壤中养分元素之间的相互制约效应和作用不同。(4)在所有土壤层中养分蓄积量总和均表现为:马尾松天然林湿地松人工林马尾松人工林,表明马尾松人工林对各养分元素的利用效率均高于其它两林分类型。3种林分养分元素蓄积量随土层加深而呈现的增长趋势明显不同。(5)3种林分土壤中的养分元素含量、养分分布、养分元素蓄积量均表现出明显的差异性,所以应采取适宜各自林分的经营管理和保护措施,来提高其生态价值和经济效益。
[Abstract]:Stand soil nutrients can provide the necessary nutrition and environmental conditions for plant growth and development, and suitable soil nutrients are the prerequisite for the cultivation of trees.However, in recent years, the excessive pursuit of economic interests and unscientific management led to a marked decline in stand quality.The study of soil nutrient status of different stands can provide scientific basis for the management and sustainable development of stands.In this paper, three types of plantation of Pinus massoniana, Pinus massoniana and Pinus elliottii plantation in karst area of Guizhou Province were divided into three types: Pinus massoniana plantation, Pinus massoniana plantation and Pinus elliottii plantation.The physical and chemical properties and nutrient characteristics of soil were studied systematically.The results showed that there was significant difference in soil bulk density between different layers of Pinus massoniana plantation and natural forest. The average soil moisture content of the three stands was 16.270.54, and the content of organic matter in surface soil was the highest, and there was significant difference between the soil and the deepest soil.The total N, K and P of Pinus massoniana plantation were significantly different in different layers of soil.The mean value of total mg in soil layer of Pinus elliottii plantation was 0.83 g / kg, that of Pinus massoniana plantation was 0.60 g / kg, and that of natural forest of Pinus massoniana was 0.82g / kg.The content of ammonium N is higher than that of other available elements.The contents of trace elements in different soil layers in natural forest of Pinus elliottii and Pinus massoniana were in different order, except the lowest soil in the artificial forest of Pinus massoniana.The content of trace elements in the soil layer of other layers was consistent. The contents of trace elements in soil layer of 3 stands were all the highest in Fe and Cr in the soil layer. 2) under the same soil layer, the content of Pb and mn in the soil of Masson pine natural forest was the highest, and the content of Pb and mn in the soil was the highest in the natural forest of Pinus massoniana.However, the content of organic matter was significantly lower than that of the other two stands, but there was no significant difference in the contents of ammonium N, nitrate N, readily available P and available K between the three stands.The range of soil pH value was 4..30.There was a negative correlation between soil pH value and other nutrient elements. There was a negative correlation between total N and ammonium N, and a good correlation between trace elements and total N in soil.The correlation between soil nutrient elements was different in the stand with significant positive correlation (P 0.05) or extremely significant positive correlation (P 0.01).The results showed that the total amount of nutrient accumulation in all soil layers was: Pinus massoniana natural forest, Pinus massoniana plantation, Pinus massoniana plantation.The results showed that the utilization efficiency of nutrient elements in Pinus massoniana plantation was higher than that in the other two stand types. 3. The increasing trend of nutrient element accumulation with the deepening of soil layer was obviously different from that of soil nutrient element content and nutrient distribution in three stand types of Pinus massoniana.There are obvious differences in nutrient accumulation, so appropriate management and protection measures should be taken to improve its ecological value and economic benefit.
【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】：2017
【分类号】：S714.8
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本文编号：1753725