【作者】 司振江；

【导师】 张忠学；

【作者基本信息】 东北农业大学 ， 农业水土工程， 2010， 博士

【摘要】 草原资源作为一种可再生的自然资源,在防风固沙、涵养水源、防治水土流失等方面具有重要作用。松嫩平原盐碱化草原是我国著名的天然草场,又是东北西部生态屏障,具有较高的经济价值和重要的生态意义。长期以来,在自然和人为因素的双重作用下,草原区超载过牧,盲目开垦使草原资源受到了严重的破坏,导致优良牧草数量减少,植被覆盖度下降,生产力降低,土壤板结,草原生态系统结构改变,生态功能减弱,造成严重的生态失衡,草原生态环境极度恶化,已对区域的经济社会发展、人民的生产生活乃至整个国民经济的健康发展构成了严重的威胁。因此,对盐碱化草原改良及生态环境修复进行深入研究具有重要的现实意义。本文通过试验,对盐碱化草原的改良方法进行筛选,为盐碱退化草原的生态修复提供有效措施,对土壤水盐动态变化、空间变异、土壤蓄保水机理进行了分析,通过生态修复评价方法对改良技术措施及效果进行了评定。根据盐碱化草原类型和分布规律,对土壤物理化学指标测试及植被种类、覆盖度及生长状况的调查,进行土壤分级与评价;考虑盐碱土处在干旱少雨、水资源缺乏自然环境,具有坚硬密实、涵养水分能力差、土地瘠薄等特殊性,通过田间试验,筛选了振动深松改良土壤和生物生化土壤改良制剂(康地宝)消减除盐的两项关键技术,振动深松在改良土壤的同时,还建立了土壤水库,疏松的土壤为盐分淋洗创造了条件;康地宝则使土壤中营养物质及微量元素转化为可利用状态被植物吸收,解除植物生理缺素症状,保证植物在盐碱土上正常出苗。对它们进行优化组合,确定最佳改良方案,试验结果表明:振动深松下,康地宝经济、有效使用量在7.5～12.5 kg /hm2之间。针对松嫩平原盐碱土分布特点以及对农牧业生产的影响,以利用降水资源为切入点,以提高草原综合生产能力为目标,以排水网络系统化配置为保障,将农艺、生化技术等进行集成,按照不同类型区确定重度、中度、轻度盐碱退化草原区,以生态恢复为重点,建立适合于区域特点的盐碱化草原综合治理及高效利用技术模式。利用水量平衡和非饱和土壤水分运动方程分析了深松土壤的蓄水保墒机理。盐碱化草原的原状土土壤坚硬而密实,土壤通透性差,涵养水分能力弱,对牧草和作物的生长发育具有抑制作用,作物的产出潜能也不能得到充分发挥。试验结果证明,经深松后的土壤,土壤结构被打破并重新组合,研究0～50cm深松层土壤的蓄水保水能力得到较大提高。根据土壤水动力学理论建立了土壤剖面一维垂直水盐运移模型,对深松土壤和原状土壤在入渗、蒸发条件下的水盐运动规律进行了模拟,同时模拟分析了再分布过程中的水分和盐分运移特征,为研究盐碱土的改良措施提供理论基础,为确定合理的生态改良模式提供理论依据。运用地统计学方法研究了0～40cm土层深松改良前后和改良1～5年的土壤水分、盐分、容重、产量等特性在空间及时间上的变异规律,利用相关统计理论模块等,通过地理信息系统(ArcGIS),建立了土壤特性图形数据和属性数据相结合的信息数据库及空间分异模型,绘制了空间分布图,能够直观地了解改良前后土壤水分、盐分等特性的空间分布情况。运用基于遗传算法(RAGA)的投影寻踪模型(PPC)进行盐碱退化草原生态修复评价分析。对放牧区、振动深松区、浅翻轻耙区、围栏封育区分别进行样本评价指标调查,每个样本有14个指标,对样本评价指标集进行归一化处理,构造投影指标函数,利用RAGA对PPC模型中参数进行优化,最后对样本进行优序排列,结果是振动深松排序在前;通过生物多样性分析,全面衡量了采用振动深松技术后物种多样性变化,从物种丰富度、生态优势度、多样性指数、均匀度指数4方面进行了分析比较,进一步揭示了改良技术对恢复草原生态环境的效果。本文以室内试验和野外观测试验数据为基础,采用定性分析和定量分析相结合、宏观分析和微观分析相结合、理论研究和应用研究相结合的方法,对试验结果进行加工分析处理,确定了盐碱化草原改良的关键技术和治理措施,建立了适合于松嫩平原盐碱化草原的改良技术模式;系统分析了深松土壤的蓄保水机理、水盐运动规律及空间变异性,对修复的生态环境进行了评价,为同类地区生态修复提供科学依据。本文创新点如下:1.首次将振动深松技术应用于盐碱化草原改良中,振动深松后的疏松土壤,可涵蓄天然降水,形成土壤水库,高效利用了降水资源;同时为盐分的淋溶创造了条件。2.针对盐碱化草原特点及措施需求,通过单项技术优化组合,形成重度、中度、轻度盐渍土分类治理措施,建立了适于松嫩平原盐碱化草原的综合治理技术模式,实现投入少,见效快、产出大的目标。3.首次对深松扰动的盐碱土进行水盐再分布规律和水盐运移模拟的研究,填补了深松土壤水盐运动规律的理论空白,为同类研究提供了借鉴。更多还原

【Abstract】 As a kind of renewable natural resources, grassland resources had important effect at the aspects of sand fixation, water conservation, preventing soil erosion, etc. The saline-alkaline grassland of song-nen plain which had high economic value and important ecological significance, not only was the natural pasture in our country,but also was the ecological barrier in west of northeast china. For a long time, under the condition of natural factors and human factors, over-grazing and blind reclamation generated the severe consequences of destroying grassland resources, reducing excellent grass, decreasing vegetation coverage and productivity, changing structure of grassland ecosystem, making soil hardening, weakening ecological function, causing ecological imbalance, deteriorating grassland ecological environment, moreover, there had been severe threaten to development of economy and society, production and life of people, and even the healthy development of national economy. Therefore, both deeply research the improvement of the saline-alkaline grassland and the restoration of ecological environment had important practical significance.The paper selected improved methods to the saline-alkaline grassland by experiment, provided effective measures for the restoration of the saline-alkaline grassland, meanwhile, the paper analyzed the dynamic changes of soil water and salt, spatial variability, and the mechanism of the storage and preservation of water, evaluated improved technical measures and effects by evaluation method of ecological restoration.The classification and evaluation were carried out, which based on the types and the distribution rule of the saline-alkaline grassland, the index testing of soil physical and chemical, the investigation of vegetation types, coverage, growth status. Considering that the saline-alkali soil had the particularity of hard and dense, poor storage capacity, soil leanness under the natural condition of drought, less rain, lack water, two key technologies which were improved soil of vibrating deeply-loosening and improved soil preparation the biological and biochemical technology (kangdibao)were selected by field experiment, vibrating deeply-loosening not only improved the soil, but also established the soil reservoir, the loose soil created the condition for the salt leaching. The improved preparation Kangdibao turned the nutrient and trace elements of the soil into the available status which was absorbed by the plant, removaled the physiological nutrient deficiency symptom, ensured normal emergence of the plant in the saline-alkaline soil. Proceeding optimum combination of the above technology, determining the improved project, the experimental results showed that the economical and effective amount of the improved preparation Kangdibao was 7.5-12.5 kg/ hm2 under the condition of vibrating deeply-loosening.According to distribution features of the saline-alkali soil and the influence of the saline-alkali soil for husbandry production in song-nen plain, taking the utilization of precipitation resources as the breakthrough point, taking the improvement of the comprehensive production capacity of grassland as the target, taking the systematic configuration of drainage network as the security, the agronomic technology and biochemical technology were integrated, according to the different type region, the severe, the moderate, and the mild of saline-alkaline grassland were determined, taking the ecological restoration as the emphasis, the technology model of comprehensive treatment and efficient utilization of the saline-alkali grassland was established, which was suitable to the regional characteristics.Using both the water balance and the unsaturated soil moisture motion equation to analyze the mechanism of the storage and preservation of water. The undisturbed soil of the saline-alkaline grassland had the characteristics of hard soil, poor permeability, weak preserving water capacity, and the inhibition for the growth of the grass and the crop, so the produced potentiality of the crop did not adequately play. The experimental results showed that the soil structure with vibrating deeply-loosening was breaked and renewedly combined, the storage and preservation of water was greatly improved in the range of 50 cm loosen.According to the dynamics theory of soil moisture, established the one-dimensional vertical transfer model of soil profile, simulated the movement rule of water-salt under the infiltration of the evaporation for the subsoiling soil and the undisturbed soil, in the further distribution process of simulation analysis, the transfer characteristics of water and salt not only provided the theoretical foundation for the improved measures of the saline-alkaline, but also provided the theoretical foundation to reasonably determine the ecological improvement model.Using the statistical method to research the time and space variation regularity of the moisture, salinity, bulk density, yield of the grass, which were pre and post improvement of the subsoiling soil in the range of 0-40cm and improvement of the range of 1-5 year, through the ArcGIS, using the relevant statistical theory module established the information database and the spatial differentiation model by the soil characteristics in the combination of the graphic data and the attribute data, drawed spatial distribution graph, visually understanded spatial distribution of soil moisture and salt in pre and post soil improvement. Application of Projection Pursuit Classification model (PPC) based on Real-number coding Acceleration Genetic Algorithm (RAGA) to evaluate and analyze the ecological restoration of the saline-alkaline grassland. Respectively proceeding the investigation to the sample evaluation indexes which contained grazing region, vibrating deeply-loosening region, shallow ploughing and light harrowing region, enclosed fence region, every sample had 14 indexes, carrying out the normalization processing for the evaluated index set of the sample, structuring the projective index function, applying RAIGA to optimum the parameters of PPC model, arranging the optimal order of the sample, the result was that vibrating deeply-loosening ranked in front. Secondly, comprehensively weighing the species diversity changes after vibrating deeply-loosening by biodiversity analysis, after analyze and compare with the species richness, the ecological dominance, the diversity index, evenness index, the effect of grassland ecological environment, which was restored by improved technology was ulteriorly revealed.The paper took the experimental data of the laboratory experiment and the field observation as the basis, adopted the methods of the qualitative analysis combining with the quantitative analysis, the macroscopic analysis combining with the microscopic analysis, theoretical research combining with application research, with analyzing and processing the experimental results, determined the key technology and treatment measure for the improvement of the saline-alkaline grassland, established the improved technology model suitable for the saline-alkaline grassland in song-nen plain, systematically analyzed the mechanism of the storage and preservation of water, the movement rule of the water-salt, and spatial variability, evaluated the repairing ecological environment, provided the reference and the scientific basis to the research of ecological restorationin similar area.Innovative points:1.Applying vibrating deeply-loosening to the improvement of the saline-alkaline grassland for the first time, the loose soil after vibrating deeply-loosening storaged natural rainfall, formed soil reservoir, effectively used precipitation resource, meanwhile, created the condition for salt leaching.2.The saline-alkaline soil was scientifically classified and evaluated, to the characteristics and measures demand of the saline-alkaline grassland, formed classification of the control measures to severe, moderate, and mild of saline soil by the optimum combination of single technology, established the comprehensive control technology modle which was suitable for the saline-alkaline grassland of song-nen plain , realized the target of the less input, fast effect, and large output.3. First researched on the redistribution rule of water-salt and the simulation of water-salt transfer to the the subsoiling saline-alkaline soil, filled the gap in the theory of the water-salt motion rule of subsoiling land, provided the reference for the similar research.更多还原