【作者】 李榜晏；

【导师】 李佩成；

【作者基本信息】 长安大学 ， 地质工程， 2007， 博士

【摘要】 本文着重以无定河上游毛乌素沙地作为实例,在分析其生态环境特征和面临的主要生态环境问题的基础上,从本区植物资源调查、结构和区系分析以及比较植物学等方面,研究了本区植物的资源状况、基本特征和典型乡土植物的适生性与封育保护途径,以便为生态环境建设与再造山川秀美服务。主要从以下几个方面开展了相关研究工作:1)本区环境特点分析;2)本区适生植物资源调查、种属构成特征及区系分析;3)本区典型杨柳科(Salicaceae)植物的生物学特性和抗逆性比较研究;4)本区适生植物资源的封育保护治理研究。通过实地考察、座谈访问、定点观测、植物采集、调查比对、室内实验分析研究、资料收集和整理等研究手段和技术方法,在本区的基本环境特点和问题、当地植物对沙地环境的适应方式和保护机理、沙漠化防治和植被重建途径等方面得到如下研究成果:(1)在分析无定河上游地区(毛乌素沙地)的自然概况和演变规律的基础上,总结出本区根本的生态环境特征可以归结为“旱、寒、风、沙、(盐)”;在这种环境背景下,本区面临的最大环境问题,简单说就是“风沙为害、沙进人退;干旱缺水;暴雨为灾,水土流失;生态脆弱,物种濒危”。(2)通过调查编制了本区适生植物资源名录(参见附件《无定河上游毛乌素沙地种子植物名录》),对本区适生植物资源的种属构成特征进行了研究,说明本区植物绝大部分属北温带分布型;本区植物区系的特点与性质的研究则提示本区植物具有多层次的生态过渡地带特点,其区系组成是在漫长的历史演变过程中形成的,其它区系分布类型的植物进入本区,主要取决于其对沙漠化环境的适应性,并通过长期的自然选择逐渐由定居、生存和发展而形成稳定的状态。这就为本区在生态环境和山川秀美工程建设等方面的适生树种、草种选择问题提供了直接的科学方向。(3)在研究过程中发现了本区统万城遗址周边尚有天然胡杨林的分布。拓展了学术上胡杨的分布范围,并对研究毛乌素沙地和统万城遗址周边地区的环境变迁和干旱半干旱地区的生态治理和植被恢复有着重要的参考价值,将有可能成为研究统万城及周边环境变迁的“活化石”和生物指示。(4)进一步研究和确认了沙柳、旱柳等乡土树种的抗逆特性和在本区生态重建中的推广利用价值;通过比较植物学研究认为,本地沙柳在抗旱等逆境生活指标上,表现的最为突出,说明其适应干旱等胁迫环境的能力最强,是较好的沙地先锋植物;胡杨作为一种重要的荒漠河岸林植物,对沙地蒸腾强烈、气候干旱的特点通过长期的进化和生物适应,表现出很强的植物抗性特征和在各种逆境中较宽的存活、繁衍的适应能力;旱柳不仅具有一定的抗逆指征,而且推测本地的水文等条件对其生长比较有利,在本地大力发展旱柳这种乡土树种,不仅简便易行,投资少、见效快,而且生态治理和经济价值都很可观。(5)提出了在本区封育治理的几种可行途径,比如建立典型适生树种的封育示范园和推广重要适生树种的沙产业生态园区,还可建立旱柳经济林产业园、沙地药用植物生态产业园、沙地景观生态产业园等;以及设立各类自然保护区和(国家)沙生植物公园。(6)本论文还从本区植物封育保护治理工作长期可持续运行的机制方面进行了理论探讨和设计,提出了建立和完善本区植物封育保护治理工作五位一体的可持续发展运行机制体系。更多还原

【Abstract】 This dissertation evolves from the nation key project "The experimental area construction of Graceful Mountains and Rivers and researches of important science and technology problems in different ecosystem regions in the northwest of China." It is the continuance of early study achievements and divisional researches. With the instance of Maowusu sandlot of upriver Wuding river, based on the analysis of its environmental evolvement character and main problems, in the aspects of plant source study, structure and category analysis and comparative botany, we study plants source, essential character and adaptive disposition and protection ways of typical native plants.The research work is based on the following aspects:1) Analysis of native environment evolvement character;2) Adaptive plants source study, genus composition character and category analysis;3) Comparative study of Botanical and anti-reverse natures of native typical plant Salicaceae4) Protection and treatment studies of native adaptive plants sterilization.Through different studies and technical methods of spot survey, discussion and visiting, spot observation, plants collection, investigation and comparison, indoor experimental analysis and study, data collection and analysis,and in the aspects of native environment evolvement character and problem, native plants adapting to and protection mechanisms from sandlot environment, desertification prevention and treatment and restoration of vegetation , we reach the conclusion as follows:(1) Environmental vicissitudes and evolvement rules of upriver of Wuding river (Maowusu Sand) clues to the essential native environment character, concluded as "cold, drought, wind, sand and salt ".In this environmental back ground, the serious environmental problem faced by this area is "sand moves forward and men backward; rainstorm causes the lapses of water and soil; frail environment results in species being in severe danger".(2) By investigating and compiling native adaptive plants source catalogue (refer to enclosure < Seed Plant Catalogue of Maowusu Sand near Upriver Wudinghe >), we study genus composition character of native adaptive botanical source. It shows most native plants belong to the North Temperate Zone distribution; the study of native plants category character indicates its multilayer significance of ecological transmission and the long time history evolvement of category composition. Other categories distribution plants ingression into native district depends on adaptations to desertification environment and long term settlement, severance, development and stability. It provides direct scientific direction to adaptive plants seeds choose of ecological environment and Graceful Mountains and Rivers Project constructions.(3) The distribution of natural Populus diversifolia is discovered and reported in this botanical source survey, which is the first in the whole Maowusu desert. To some extent, it would be living fossil and biological indication for studying Tongwancheng and its surrounds evolvement. It enlarges botanical distribution area of Populus diversifolia and is of important reference value to studying environmental evolvement of Tongwancheng site surrounds, ecological treatment and vegetation recurrence of drought and semi-drought districts.(4)Through comparative botanical study, we conclude as follows: the prominent anti-drought nature of native S.flarida in adversity explains its excellent adaptation to drought and adversities and a suitable sand pioneer plant; As an important hungriness and riverside plant, Populus diversifolia expressed strong surviving and multiplying botanical characters through long time evolvement and biological adaptation in drought sand and climate. The anti-adversity character of S.matsudana and favorable native hydrological promise low investment, fast effect, considerable ecological treatment and economic values for vigorous development of S.matsudana. (5) Here proposed several possible sterilization ways, such as building typical adaptive plants sterilization demonstration garden, popularizing sand industrial environment district of important adaptive plants,(taking Hanliu economic forestry district, sand officinal plant environmental industrial district, sand sight environmental industrial district as examples.)and building natural protection zone and national sand plant parks.(6) Lastly, from theoretical discussion and plan of long term sustainable operating mechanism of native plants sterilization protection and treatment, we proposed constructing and perfecting long term sustainable operating mechanism of native plants sterilization protection and treatment. Proceeding with inter-knitting and inter-supporting aspects of managing and organizing mechanism, compensation mechanism, afterward industry chain plan and circulation development mechanism, innovation mechanism and publication mechanism, a complete set of quinaritarian operating mechanism is build.更多还原