【作者】 陈学平；

【导师】 张洪江； 江玉林；

【作者基本信息】 北京林业大学 ， 水土保持与荒漠化防治， 2009， 博士

【摘要】 适用植物的选择是植被重建的基础与前提。本研究利用植被生态学理论基础,研究了护坡植物的适宜性及植被重建中重建程度、重建方式、群落质量与土壤侵蚀量的关系,总结提出了植被重建的适用技术。主要结论如下:1.护坡植物筛选评价了19种木本植物、8种草本植物的初期竞争能力、抗逆性、生长势等性能指标,并以隶属度值为基础进行了护坡植物适宜性分类排序。将护坡植物划分为5类,以马棘、苦刺表现最优;波叶山蚂蟥、狗牙根、苦楝、刺槐、截叶胡枝子、荆条、百喜草表现良好;高羊茅、弯叶画眉草、柘树、盐肤木、坡柳、决明、冻绿、臭椿、百脉根表现中等;枫杨、鸡眼草、乌桕、假俭草、白三叶等表现较差;马尾松表现差。2.护坡植被重建技术研究了不同植物组合的草灌竞争特征与优势种群建成情况,结果表明利用草灌间生长习性差异可以实现灌木建成,灌木种类间适宜性程度差异影响着灌木种群之间竞争平衡。苦刺与荆条、马棘与刺槐、截叶胡枝子与苦刺等适宜性差异小的种类间易于形成协调平衡的混交群落,而适宜性差异大的则易形成单一化群落。草灌组合群落综合质量在3a时均优于普通草本组合。与自然环境植被相对比,人工重建植被群落内物种数目少、植物多样性低、土壤有机质含量水平低。在基于植被种间竞争关系分析的基础上,总结提出了通过草灌竞争调节、组合模式设计、时空间隔种植等实现灌木植被建成技术。针对项目区的边坡特点,划分了硬质边坡、软岩边坡及土质或土夹石边坡3类边坡类型,分别提出了坡面综合防护与植被设计等关键技术,其中阶梯式空心砖护面墙绿化技术、L形种植槽挡板绿化技术、硬岩边坡的钻孔绿化技术均是国内的首次尝试,并取得初步成功。3.护坡植被重建对土壤侵蚀的影响研究了公路坡面不同植被重建程度、植被重建模式,植物群落质量与降雨因子耦合对土壤侵蚀量的影响,结果表明植被的重建、保护均有助于提高土壤的防侵蚀能力,植被恢复程度对土壤保持具有正效应。建成植被坡面雨季土壤侵蚀量最低,仅为13.8t/km~2,在相同降雨条件下,综合重建小区、自然恢复小区、简易植被措施小区的相同降雨条件下土壤侵蚀量分别为裸露坡面小区的75.9%,27.4%及23.9%。裸露坡面当年雨季土壤总侵蚀量可达20684.5 t/km~2。对裸露坡面、简易植被措施坡面的降雨量与土壤侵蚀量有极显著的正相关关系,植被建成后,降雨量与土壤侵蚀量关系不显著。硬岩边坡植被重建中人工客土的滑塌是主要形式,并可导致植被重建失败。在试验区降雨条件下,不同组合模式植被群落建植当年土壤侵蚀量不同,侵蚀强度在15406—17926 t/km~2之间。快适型与先锋型草灌组合表现最佳,包括高羊茅+紫羊茅+马棘+截叶胡枝子+桤木+刺槐组合与高羊茅+紫羊茅+木豆+山毛豆+猪屎豆组合,前者中的马棘与刺槐组合是项目区较为理想的植物组合类型;高羊茅+紫羊茅+截叶胡枝子+马棘+紫穗槐组合土壤侵蚀量最大。群落地上生物量积累量与土壤侵蚀量之间的相关性显著大于植被盖度、密度及其他草灌指标的影响,植被重建宜选择地上生物量积累迅速的植物组合类型。更多还原

【Abstract】 Selection of adapted plants set the base of revegetation.Plants’ adaptation ability for slope protection,degree and mode of revegetation,community quality and soil erosion correlation during revegetation process were studied,based upon which revegetation techniques were summarized.Main conclusions are as follows:1.Screening of plants for slope protectionNineteen woody plants and eight herbaceous plants were studied for their early competition ability,adverse environmental stress hardness and growth potential,and were classified based upon hierarchical cluster analyze and subordinate function value.The experimental plants can be classified into five categories:Indigofera pseudotinctoria and Solanum deflexicarpum have the best performance;Desmodium sinuatum,Cynodon dactylon,Melia azedarach,Robinia pseudoacacia,Lespedeza cunecta,Vitex negundo, Paspalum notatum rank the second;Festuca arundinacea,Eragrostis curvula,Cudrania tricuspidata,Rhus chinensis,Dodonaea viscosa,Senna obtusifolia,Rhamnus utilis, Ailanthus altissima,Lotus corniculatus rank the third;Pterocarya kunth,Kummerrowia stipulacea,Sapiu sebiferum,Eremochloa ophiuroides,Trifolium repens rank the forth; Pinus massoniana Lamb rank the poorest.2.Revegetation techniques for slope protectionHerbaceous and woody plants competition characteristics and predominance of established species were studied,the results show woody vegetation can be established taking use of the difference of growth habit,and the gap among woody plants set a main factor to affect competition balance.The balance between species with close growth habit are prone to achieved,such as the balance between Solanum deflexicarpum and Vitex negundo, lndigofera pseudotinctorea and Vitex negundo,Lespedeza cunecta and Solanum deflexicarpum, while mixture with wide gaps of growth habit tend to form single predominance species. Mixture of herbaceous and woody species has better performance than that of common herbaceous mixture in 3a.Artificially revegetation has much fewer species,less abundant biodiversity and lower level soil organic matter compared With natural vegetation. Regulation of competition between herb and wood,mixture mode selection,and temporal and spacial alternation growing methods were advised to establish woody plants.Tree types of side slope of highway including hard rocky type,soft rocky type,earth or earth-stony type were identified and corresponding slope protection and revegetation design were carried out,among which vertical landscaping techniques including ladder like hollow brick landscaping,L-shape concave growing for the masonry retaining wall face-landscaping and drilling hole for growth on hard rocky slope were the first practice domestically and lead to early success.3.Effect of revegetation on side slope soil erosion controlRevegetation degree,mode and quality and it’s coupling effect with precipitation were studied and results indicated that both revegetation and protection practice of previous vegetation contribute to soil preservation,the degree of revegetation have a positive effect on soil preservation.Well revegetated slope has the least amount of soil loss with 13.8 t/km~2 in rain season.Soil loss amount of early stage of comprehensive slope,poorly and naturally reestablished slope,and simple reestablished slope were individually 75.9%, 27.4%and 23.9%of the rate of bare slope.Soil loss for bare slope can reach 20684.5 t/km~2 in rain season.Soil loss of barren slope and that of simple revegetated slope correlated with precipitation significantly,while well revegetated slope performed insignificantly.Artifial soil slide is the main performance for hard rocky slope and can lead to the failure of revegetation.Different revegetating measures of plants mixture differed in their soil erosion under the precipitation condition of experiment area with an amount of 15406—17926 t/km~2 in rain season.Fast adapted mixture and pioneered mixture of herbaceous and woody plants have the best performance,which including Festuca arundinacea + Festuca rubra + Indigofera pseudotinctorea + Lespedeza cunecta + Alnus cremastogyne Burk + Robinia pseudoacacia,Festuca arundinacea + Festuca rubra + Cajanus cajan + Tephrosia candida +Crotaria assamica,Indigofera pseudotinctorea and Robinia pseudoacacia in the former mixture are idea mode for the area;mixture of Festuca arundinacea + Festuca rubra + Lespedeza cunecta + Indigofera pseudotinctorea + Amorpha fruticosa has the largest soil loss amount than other mixture.Above ground biomass related significantly with soil loss, other than coverage,plants density and other indices.Mixture with fast above ground biomass accumulation should be taken into account for better revegetation.更多还原