【作者】 张千千；

【导师】 高宝嘉；

【作者基本信息】 河北农业大学 ， 生态学， 2009， 硕士

【摘要】 考虑林水矛盾和优化林水相互关系是在西北半干旱地区进行林业生态环境建设时必须重视的核心问题,本文在处于半干旱区的六盘山北坡叠叠沟小流域研究了当地主要植被类型的生长及其耗水规律,典型坡面的土壤水分动态变化规律,有关结果充实了半干旱地区林水关系研究中植被和水分相互影响的内容,利于促进发展半干旱地区森林植被建设和管理的理论与技术,提高林水协调管理水平,为当地植被恢复与植被建设提供科学指导。具体结果如下:1.土壤水分动态土壤水分变化分期和分层:结合研究期间降水分布比较了不同典型样地(0～180 cm)土壤水分的季节变化,可分为土壤水分积累期、消耗期和恢复期;不同样地(0～180 cm)土壤水分垂直变化可大致分为土壤水分速变层、利用层、次要利用层和稳定层4个层次。土壤含水量变异系数的坡面变化:0～100 cm土层的土壤水分变异系数(CV%)在阴坡从坡下部华北落叶松林样地(22.4%)向上呈波浪式增加趋势;阳坡草地土壤含水量变异系数沿坡面从下向上呈波浪式增加趋势;阳坡坡面土壤水分变异系数范围在22.1%～38.5%之间。半阴坡土壤含水量变异系数的范围为23.5%～43%,在坡面呈单峰型变化趋势。2.坡面典型植被的生长特征华北落叶松高生长:对本研究涉及的阴坡华北落叶松人工林林分,以其年高生长速率可划分为缓慢生长期(栽植后5年)和迅速生长期(5～20年)。连年高生长有多种影响因素,相同立地同龄林木的高生长受林木生长和空间特征影响;不同立地同龄林木的高生长同土层厚度呈正相关,其次受林分密度影响。林分密度与林木高生长相关性不很高,说明密度不能很好映林木间竞争关系。阴坡草本植被:阴坡坡面共出现29种植物,各月的物种丰富度均随坡长增加表现为先升高后降低,呈明显的单锋格局,峰值在坡中部出现。阳坡草本植被:阳坡坡面共出现23种植物种类,物种丰富度从坡脚向坡顶呈波浪式逐渐减少趋势。在坡面,总生物量沿着海拔的增加呈现出波浪式的变化。地下生物量以则在坡中下部的1-3号样地最大,坡中上部的1-7号样地最小。半阴坡草本植被:半阴坡坡面共出现26种植物,物种丰富度从坡脚向坡中部呈波浪式变动趋势,而由坡中部向坡顶则逐渐降低。总生物量沿海拔增加呈现波浪式变化。地下生物量的变化趋势与总生物量一致,而地上生物量的变化规律在整个坡面上不很明显,可见半阴坡草地的总生物量变化趋势取决于地下生物量变化。同时也发现半阴坡草地各样地的地上生物量也均明显小于地下生物量。更多还原

【Abstract】 Considering and optimazing the interrelationship between forest/vegetation and water resources is one of the important subjects for ecological reconstruction and vegetation restoration in the semi-arid zone of Northwest China. In this paper the growth and water use regularities were studied for main vegetation type which is one of the main plantation tree species on north side of the Liupan Mountains. This study is helpful to understand the interrelation between plantation growth and water condition in the semiarid area, and to promote the development of theories and techniques of the restorationan of forest/vegetation in semiarid area. The research conclusions could offer scientific guidance for the harmonious and integrated management of forest and water. The main conclusions were as follows:1. Study on dynamics of soil waterSoil water dynamics during different periods and between different layers: Considering the precipitation during the research period, the soil water seasonal dynamic in different typical plots(0~180cm) can be divided into accumulating period and consuming period and restoring period; soil water dynamics in vertical direction can be divided into soil water variable greatly layer, soil water using layer, soil water subactive using layer and water stable layer.The law of soil water variation in different position on slope: the variance coefficient of soil (0~100 cm) water of Larix principis-rupprechti ahowed a fluctuant rising;The variance coefficient of sunny slope soil water showed a fluctuant rising. The variance coefficient ranged from 22.1% to 38.5%. The variance coefficient of soil water of semi-shady slope showed single peak and the variance coefficient ranged from 23.5% to 43%.2. Hillslopes typical characteristics of vegetation growthLarix principis-rupprechti high growth: Of this study involved Larix principis-rupprechti shade slope in Plantation forest, Its high growth rate can be divided into a slow growth period (5 years after planting) and the rapid growth period (5 ~ 20 years). High-growth year after year there are several factors, the same site of the same age, height growth of trees by tree growth and the impact of spatial characteristics; Different site of the same age, height growth of trees with the soil thickness was positively correlated, followed by the impact of stand density.Stand density and tree height growth is not very high correlation showed that the density can not be good relations between the competition.Shady slope herbaceous vegetation: The Slope of the shade slope there were 29 kinds of plants, each month species richness increased with slope length increased were showed increasing first and then decreasing each month, was clearly a single-front pattern of the central peak appears in the slope.Sunny slope herbaceous vegetation: Sunny slope there were 23 kinds of plant species, species richness to just over a hill from the foot of the slope peak showed a wave-like gradually decreasing trend. In the slope, total biomass increased along the elevation showing a wave-like changes. To below-ground biomass in the lower part of the slope in the plot of the 1-3 largest slope in the upper part of the smallest sample 1-7.Semi-shady slope herbaceous vegetation: The Semi-shady slope, there were 26 kinds of plants, species richness from the foot of the slope to the middle slope changes in the trend of a wave-like by the middle slope is gradually reduced to the slope peak. Total biomass along an altitudinal increase in a wave-like changes. Below-ground biomass trends consistent with the total biomass, and aboveground biomass of the change of in the whole slope is not very clear, we can see the semi-shade slope glass of the trend of total biomass change depending on changes in below-ground biomass. At the same time, It is found that the semi-shade slope each sample plot of above-ground biomass were also significantly less than the below-ground biomass.更多还原