【作者】 王志泰；

【导师】 李毅；

【作者基本信息】 甘肃农业大学 ， 水土保持与荒漠化防治， 2012， 博士

【摘要】 为了解边坡生态防护工程植被建植初期植被特征与土壤养分变化规律和石质边坡人工植被自然化过程规律，本论文依托实际工程，选择3个不同坡向、坡度的石质边坡作为样坡，在人工植被建植后2周年内，采用定位研究法和常规群落调查法，对群落特征（物种、盖度和高度等）和土壤养分因子（有机质和速效态养分元素）每月进行跟踪测试。选择黔中地区不同建植年限（2a、4a、7a和10a）、人工植被保留较好的石质边坡，运用典型样地法调查分析群落物种组成、群落数量特征、群落组成结构特征、土壤种子库物种组成与丰度，比较了人工植被地上群落与土壤种子库的相似性。主要研究结果如下：1.植物群落建植初期，随着人工植被的定植，公路边坡生境条件得到一定程度的改善，为当地物种的入侵提供了可能的条件，一些1年生的先锋植物在第2年开始入侵，物种数在第2周年末，由初植萌发的4、5种增加到20余种。植被建植初期的2个月内，不同坡向和坡度的边坡之间在群落物种组成和盖度等特征方面存在显著差异，随着边坡植被的大面积覆盖，坡向和坡度对群落特征的影响已不明显。2.人工边坡植被建植初期，群落物种主要是草本植物，植被物种、盖度和高度方面发生明显的季节性变化。边坡植被一年中有两个枯黄期，存活部分盖度在8、9月和冬季突然降低。边坡植被盖度在生长旺季（11月）保持了较高的水平（80%以上），且第2年高于第1年。建植后的第1年，喷播物种处于优势地位，群落高度在季节性变化的过程中总体较低，第2年同比第1年，群落高度明显增加。3.随时间推移，群落物种丰富度在增加，群落α多样性水平总体上在提高，群落的组成结构由人工初播的较简单水平向复杂水平转化。群落的物种β多样性水平的动态变化直观地表现了群落物种更替和自然化的过程。4.土壤碱解氮和有效磷含量在植被建植后两年内波动下降，均低于建植初水平；1、2号坡速效钾含量在波动变化后有所下降，3号坡在波动变化后略有上升；有机质的含量在第1年波动变化后大幅度增加，第2年前3个月明显下降，之后基本持平，第2年末比第1年末有所下降。植被建植的初期阶段（2年内），植被特征相关指数与土壤养分因子之间的相关性不显著，说明这一时期植物生长、边坡土壤结构、土壤理化性质及土壤微生物等发生更为复杂的交互影响关系。5.相同恢复年限边坡各样坡群落类型统一。植被盖度表现出随时间推移而降低的趋势，10a边坡群落植被盖度最小为50%，其余恢复年限边坡盖度基上维持在较高水平。边坡人工植被土壤覆盖度在前期为100%，7a坡开始有零星土壤剥落，但土壤覆盖度仍较高（≥85%），土壤平均厚度随恢复时间的延长呈逐渐下降的变化趋势。6.人工植被建植后，群落物种数随时间推移不断增加，当地乡土物种逐渐占据优势取代初播物种，在人工植被群落的优势种向入侵自然物种过渡阶段群落形成多优势种群，群落物种数量最多，之后当地禾本科植物逐渐占优势地位又形成单优群落，群落物种数有所下降，初播物种基本被乡土物种所取代，乡土木本植物进入群落，其根系向下延伸，对人工喷附土壤的依赖逐渐降低，有望形成的喀斯特岩溶植被。7.禾本科、豆科和菊科植物在人工植被自然化演替的初期，发挥着巨大的作用。禾本科植物以其出苗快、生长迅速等特点，能在短期内迅速覆盖祼坡，且具有强较的分蘖力和耐瘠性，在初播物种中作为主要的建群物种。当地菊科植物和禾本科植物的大量入侵改变了群落的组成结构，逐渐替代了初播物种，使石质边坡植物自然化程度有所增加。豆科植物虽然具有固氮作用，但在种类与数量上并未表现出特别的优势。经过10年的演替，木本植物开始占据较大的群落空间，植被群落表现出由草本阶段向草灌阶段过渡的特征。当地自然入侵物种在保证人工植被群落向自然化植被群落演替过程中起到了重要作用，保证了边坡植被恢复的连续性和持续性。8.黔中岩溶地区高速公路石质边坡人工植被—土壤系统的土壤种子库具有丰富的植物种子，。不同恢复年限的边坡中地上植被与土壤种子库的物种组成具有一定程度的相似性，然相似性均小于0.5。植物群落地上部分与地下部分在优势种、生活型组成与功能型组成上具有明显的相似性。9.黔中岩溶地区公路石质边坡人工植被建植后的10年自然化过程表现为：人工栽植草丛植物群落阶段（1－4a）、人工初播植物与乡土自然植物共存竞争草丛群落阶段（4－7a）和自然草灌群落阶段（7－10a）。更多还原

【Abstract】 To understand the vegetation characteristics and variation of matrixnutrients in the initial vegetation planting of side slope ecologicalprotection and the naturalizing law of artificial vegetation of the rocky sideslope. Based on the actual project, this paper selected3rocky slopes withdifferent slope aspect and different gradient as sample slopes, and takingpositioning method and conventional community survey method, testedcommunity characteristics (Species, cover, height, etc.) and soil nutrientfactors monthly (available nutrient elements) within2years of the artificialvegetation planting. Besides, using typical plot method, the researchselected the good retention vegetation of rocky slopes with differentplanting years(2a、4a、7a and10a) in Guizhou province, investigated andanalyzed the species composition, population characteristics, communitycomposition structure features, composition and abundance of soil seedbank species, and compared the similarity between artificial vegetationcommunity on the ground and soil seed bank. The main research resultswere as follows:1. At the initial planting of plant community, the initial seeding specieswas growth rapidly due to the rich sunny and soil nutrient, and the speciescomposition, coverage and height were in the ascendancy, but speciesnumber were fewer. With the planting of artificial vegetation, the habitatconditions of highway slope had a certain extent improvements, whichprovided the possible conditions for native species to invade. Some1-yearpioneer plants began invasion in the2nd year, and the species number wasincreased from4~5initial germination species to more than20at the end ofthe2nd anniversary. In the first early2months of vegetation planting, therewas significant difference in the species composition and coverage betweenslopes with different slope aspect and slope gradient. With the area of the slope vegetation expanded, the effect of slope aspect and gradient tocommunity characteristics was not obvious.2. In the initial artificial planting of slope vegetation, communityspecies were mainly herbs, and showed seasonal changed in terms ofspecies, coverage and height with the time passing. Slope vegetation hadtwo periods of brown during one year, and the coverage of surviving partsuddenly reduced in August, September and winter. Overall, the coverageof slope vegetation in growing season (November) maintained a relativelyhigh level (above80%), and the second year was larger than the first year.The first year after the establishment, spray species was in the ascendancy,however, community height was overall lower in the process of seasonalchanges. Compared with the1st year, community height of the second yearincreased obviously. Within2years of artificial vegetation planting,community maintained a strong growth and the effect of recovery wasgood.3. With the time passing, richness of species increased, communityalpha diversity improved generally, and community composition andstructure were transformed from the simple to complex in the earlyartificial seeding. The dynamic changes of community species betadiversity visually displayed the process of community species turnover andnaturalizing.4. Soil available phosphorus and alkaline nitrogen mass fractiondeclined in two years after the planting of vegetation, and were lower thanthe early establishment. Available potassium mass fractions of No.1andNo.2slopes were declined after wave changes, yet the No.3slope increasedslightly. Mass fraction of organic matter increased significantly in the firstyear, and declined obviously in the first three months of the second yearand then basically stabilized. The correlation between related indices ofplant characteristics and soil nutrient was not significant after the initial vegetation planting (within2years). It indicated that the plant growth,slope soil structure, soil physical and chemical properties and soil microbeeffected more complex interactions during this period.5. The community types of all slope plots with the same recoveryperiod were consolidated. Vegetation coverage expressed the decreasetrends with the time passing. The vegetation coverage of the10years slopewas least, only50%, and that of the remaining recovery periods basicallyremained at a higher level. The soil coverage of slope artificial vegetationwas100%at the early stage. It was fragmentary soil peeling off from7years, but soil coverage was still high (≥85%). The average thickness ofsoil was gradually declined with the extended recovery time.6. After the establishment of artificial vegetation, the number ofspecies was increased over time. And then native species were becomingdominance gradually and then replaced the early planting species, andformed mass-dominant species in the transition stage which was from thedominant species of artificial vegetation community to the invasion ofnatural species, number of species was the largest. Then native gramineousplants had a dominant position gradually and formed single-dominancecommunity, number of species declined, and the early planting specieswere replaced by native species, native woody plants went into thecommunity, and declined the dependence of artificial spray soil for its rootswere outspreading downward, and could formed karst rocky vegetation.7. Gramineae, legume and compositae plants played a significant rolein early natural succession of artificial vegetation. Gramineous plants couldcover stark slope in the near future rapidly for its seeding emergence andrapid growth, and formed the main constructive species in early sowingspecies due to its better tillering ability and barren tolerance. Massiveintrusion of native compositae and Gramineae plants changed thecommunity composition and structure, replaced the early planting species gradually, and increased the naturalizing degree of rocky side slope plant.However, legumes plants did not show special advantages on type andquantity though it had nitrogen fixation. After10years of succession,woody plants began to occupy a larger community space. Vegetationcommunities expressed transition characteristics from the herbaceous to thegrass-shrub stage. The native invasive species played an important roleduring the process of artificial vegetation community changed to thenatural succession of vegetation communities, and ensured continuity andsustainability of slope vegetation recovery.8. The soil seed banks in artificial vegetation-soil system of thehighway rocky slope in karst area of central Guizhou Province had richplant seeds. It was a certain degree similarity in species compositionbetween soil seed bank and aboveground vegetation with the differentrecovery years of slopes, but the similarity index was less than0.5. Andthere was obvious similarity in dominant species, living composition andfunctional composition between aboveground and underground parts ofplant community, which indicated that it had synchronicity in the growthon the ground and underground parts during the herbaceous stage of rockyslope artificial vegetation restoration in karst area.9. The naturalizing processes within10years after the establishmentof the artificial vegetation on highway rocky slope in karst area of centralGuizhou province was: artificial planting grass community stage (1-4a),coexistence and competition of early artificial planting plants and nativeplant grass community stage (4-7a), natural grass-shrub community stage(7-10a).更多还原