沙埋和土壤水分对冀北沙荒地封禁条件下土壤种子库的影响

发布时间：2018-07-17 16:06

【摘要】：风沙活动、土壤干旱和人为干扰是限制冀北沙荒地植被自然恢复的主要因子。该研究以冀北沙荒地封禁区、未封禁区为研究对象,自然保护区为对照,采用野外采样与室内种子萌发试验相结合的方法,施予干旱、良好水分、水渍3类水分条件处理和埋深0.5cm和2.0cm的2种沙埋处理,分别研究土壤种子库物种组成、多样性,并探讨地上植被与土壤种子库间的相似性关系。结果表明:封禁区、未封禁区均为良好水分条件下物种数最多,多样性指数和丰富度指数最大,而自然保护区在任何水分条件下物种多样性指数均较高,且物种数均明显高于封禁和未封禁区,说明水分是限制沙荒地土壤种子库种子萌发的主要因子,封禁对自然保护区种子库种子萌发影响较小。封禁区和未封禁区不同沙埋处理物种数及物种组成完全相同,自然保护区沙埋0.5cm处理的物种数明显高于沙埋2.0cm的处理,并以多年生草本为主,双子叶植物居多,偶有乔灌木出现;封禁区、未封禁区未出现灌木和乔木,说明沙埋对封禁区、未封禁区土壤种子库多样性影响较小,对自然保护区影响较大。封禁区、自然保护区土壤种子库与地上植被Sorensen相似性指数表现为:良好水分干旱水渍,未封禁区表现为良好水分条件种子库与地上植被相似性最小,表明水分条件对封禁区、自然保护区土壤种子库与地上植被关系影响较大,对未封禁区影响不大;无论何种沙埋处理土壤种子库与地上植被相似性指数均较低,说明土壤种子库与地上植被物种组成差异较大,种子库与地上植被关系受沙埋厚度影响较大。在土壤水分条件良好时封禁条件下物种多样性高于未封禁条件,说明土壤水分条件适宜时,封禁措施能提高地上植被物种多样性;封禁区、未封禁区、自然保护区无论何种处理,Sorensen相似性指数均较低,表明封禁措施对土壤种子库物种数量与地上植被关系影响不大。
[Abstract]:Wind and sand activities, soil drought and human disturbance are the main factors restricting the natural restoration of vegetation in sandy land in northern Hebei Province. This study takes the forbidden area of sandy land in the north of Hebei Province as the research object, not the forbidden area as the research object, and the natural reserve is the control, using the method of combining field sampling and indoor seed germination test, giving drought, good moisture and water stains of 3 kinds of water strips. The species composition and diversity of the soil seed bank and the similarity relationship between the aboveground vegetation and the soil seed bank were studied by 2 kinds of sand burying treatment and buried depth 0.5cm and 2.0cm. Under any water condition, the species diversity index was higher, and the number of species was obviously higher than that of forbidden and unsealed forbidden area, which indicated that water was the main factor to restrict the seed germination of soil seed bank in sandy land. The effect of closure on Seed Germination of natural reserve seed bank was small. The number of species treated with sand buried 0.5cm in natural reserve is obviously higher than that of sand buried 2.0cm, and mainly perennial herbs, many dicotyledonous plants and occasional trees and shrubs. The soil seed bank of the natural reserve and the Sorensen of the aboveground vegetation were characterized by good water arid water stains, and the lowest similarity between the seed bank and the aboveground vegetation in the unsealed area, indicating that the soil seed bank and the aboveground vegetation were affected by the water conditions. The difference between soil seed bank and aboveground vegetation similarity index is low, which indicates that the difference of soil seed bank and aboveground vegetation species composition is larger, the relationship between seed bank and aboveground vegetation is greatly influenced by sand burial thickness. The species diversity is higher than that in the condition of good soil water separation condition. When the condition of soil water is suitable, the closure measures can improve the diversity of vegetation species on the ground, sealed area, no forbidden area, and no matter what treatment in the nature reserve, the similarity index of Sorensen is low, indicating that the closure measures have little influence on the relationship between the number of soil seed banks and the relationship between the aboveground vegetation.
【作者单位】：河北农业大学林学院;廊坊市水务局;中国建设银行鹿泉分行;
【基金】：国家林业局948资助项目(2009-4-29);国家林业局行业公益专项资助项目(201404214)
【分类号】：S714.3

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