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51.
De Gao 《湿地科学》2013,11(1):21-26
The application of arbuscular mycorrhizal (AM) inocula in severely degraded wetlands could ensure success in restoration.Mycorrhizal fungi play an important role in plant individual’s survival and development in a low nutrient condition.Based on the importance that mycorrhizal fungi have to their host plants,mycorrhizal inocula have been produced and applied in terrestrial ecosystems in order to let the plants become mycorrhizal.However,mycorrhizal inocula have not been used in wetland restorations,despite increasing evidence that mycorrhizal fungi are commonly found in various wetland systems and have the ability to survive under anoxic conditions.Evidence also shows that mycorrhizal fungal inocula in the soil could have been destroyed in the degraded wetland or could be destroyed during traditional wetland restoration process.Therefore,AM inocula production is strongly recommended for wetland restoration.In this paper,I will argue that AM inocula production is required when introduced recovery is necessary,and aeroponic culture technique is a preferable method to produce AM inocula.Last,a renewed wetland restoration flow chart is summarized.  相似文献   
52.
塔里木河下游生态输水及植被恢复遥感监测评价   总被引:8,自引:1,他引:8  
邓铭江 《冰川冻土》2007,29(3):380-386
在干旱区内陆河流域,由于水资源过度开发利用,生态环境退化已成为普遍现象.向断流的河道和生态退化区域实施生态输水,是河流生态系统恢复的基本行为和必然过程.基于向塔里木河下游7次生态输水过程中地表水、地下水、植被恢复等系统监测,并运用卫星遥感技术,对生态输水后植被恢复响应特征指标NDVI(植被指数),进行了系统研究分析,并提出植被相对恢复度的评价方法.  相似文献   
53.
海岸作为海洋资源开发、沿海经济发展的重要支撑,大量人口、产业向海岸带区域聚集,高强度的人类活动导致海岸带环境日益恶化、自然岸线严重受损、海岸带资源锐减。海岸整治修复成为保护海岸带生态环境、恢复海岸带资源的重要技术手段。为评价人工海岸生态化改造及整治修复工作效果,基于国内外学者对海岸生态修复的研究成果,综合考虑生态指标、经济指标和功能指标三方面,筛选出50项产出性指标构建人工海岸生态化改造及修复效果评价指标体系,力求科学全面、客观合理地评价人工海岸整治修复效果,为人工海岸生态化改造及整治修复工作的检查、考核以及验收提供参考依据。  相似文献   
54.
袁才 《地质与勘探》2016,52(1):182-190
目前常用的古构造图的制作方法为"厚度图法"和"断层平移法",这两种方法对断控圈闭为主的古构造恢复具有一定的局限性,且不能定量化的研究古构造生长发育情况。本论文首次将三维古构造恢复技术应用于珠江口盆地番禺-流花地区。三维古构造恢复技术在应用时,避免了厚度异常现象,实现了去压实恢复,能够更真实的反映古构造情况。该技术在珠江口盆地番禺流花地区"A"构造的应用,达到了定量分析古构造发育的效果,并且认识到了A构造在关键时期T32时期古构造幅度较小,后期构造幅度增大是A构造充满度过低的重要原因之一。  相似文献   
55.
大型无脊椎底栖动物是水生态系统的重要组成部分,也是评价生态系统状态的重要指标.本文比较了洋澜湖修复示范工程实施水域(修复区)和未实施水域(未修复区)水质和大型无脊椎底栖动物群落差异,并对湖泊生态状态进行了评价.结果表明,治理后修复区总氮、总磷和叶绿素a浓度显著低于未修复区,修复区透明度显著高于未修复区.共发现底栖动物30种,隶属于3门4纲12科,其中修复区29种,未修复区19种.修复区与未修复区软体动物的平均密度分别为369.3和34.7 ind./m2,平均生物量(湿重)分别为102.9和37.2 g/m2.耐污值指数和多度量指数评价结果显示,修复区生态系统状态优于未修复区.结果表明,结合透明度改善、鱼类控制与沉水植物重建等手段为主的湖泊修复能改善水质和生态状态.  相似文献   
56.
多次叠加技术在探地雷达资料处理中的应用   总被引:10,自引:2,他引:10  
将地震方法中的多次叠加技术引入探地雷达资料的处理中,以增强雷达的深部弱信号,取得了良好的效果.  相似文献   
57.
River regulation and river training have been performed for various purposes and negative effects have been shown in numerous cases. In some cases the negative effects are so serious that humans have to consider to "renaturalize" the regulated rivers. Only by using the strategy of integrated river management the diverse river uses and natural fluvial processes and ecological systems may be harmonized. Based on analysis of case studies and data collected from literatures this paper presents the concept of integrated river management and four principles of river training. The integrated river management comprises: 1) taking the watershed, upper stream basin including the tributaries, middle and lower reaches and the estuary as an integrated entity in the planning, design and management; and 2) mitigating or controlling the negative impacts on hydrology, erosion and sedimentation, fluvial processes, land use and river use, environment and ecology while in achieving economic benefit from water resources development, flood safety management and hydropower exploitation. River training and management should be in accordance with the four principles: 1) extending the duration of river water flowing on the continent, which may be achieved by extending the river course or reducing the flow velocity; 2) controlling various patterns of erosions and reducing the sediment transportation in the rivers; 3) increasing the diversity of habitat and enhancing the connectivity between the river and riparian waters; and 4) restoring natural landscapes.  相似文献   
58.
太湖湖滨带类型划分及生态修复模式研究   总被引:3,自引:0,他引:3  
太湖湖滨带岸线总长405 km,73%以上被防洪大堤所包围,其余部分临近山体,属于典型的大堤型湖滨带.按照湖滨带地形地貌分为大堤型、山坡型、河口型三类,根据水文条件和露滩情况,又将大堤型分为长期露滩、间歇露滩、无滩地型,山坡型分为有滩地型、无滩地型,形成6种类型的湖滨带.根据以上太湖湖滨带划分类型,结合湖滨带生境、气候、水文条件以及植被分布现状等因素,分别采取生态保育、生态修复、生态重建的对策,设计了不同类型的太湖湖滨带生态修复模式,并分别提供了形象的修复模式示意图,以期为太湖及其类似湖滨带的生态修复提供一定的借鉴.  相似文献   
59.
Historical planform changes in a 14.7 km reach of the lower Pages River were determined to assess whether they were autogenic (inherent in the river regime) or allogenic (driven by external changes) in nature so as to better focus river management activities and river restoration works. A pattern metamorphosis or complete change in river morphology occurred during the February 1955 flood. The peak discharge of this event exceeded the slope and grain size (intrinsic) threshold for braiding, converting the narrow, slightly sinuous stream to a wide, braided-like river. Five subsequent intrinsic threshold-exceeding floods did not cause further bar development because an over-widened channel already existed. Autogenic channel planform changes included sinuosity variations due to lateral migration and pattern metamorphosis due to the exceedance of a discharge–slope–grain size geomorphic threshold. Allogenic channel planform changes included: (1) realignment/channel straightening and artificial cutoffs by river training works; (2) lateral migration by increased bank erodibility due to riparian vegetation clearing; (3) lateral migration by the operation of a transitive geomorphic threshold involving the onset of a flood-dominated regime after 1946 and increased catchment runoff after 1830 due to large-scale clearing of catchment vegetation; and (4) the occurrence of a large flood in February 1955. Multiple forcing factors have clearly caused historical channel planform changes of the lower Pages River, making the design of river management and restoration works a complex matter outside the scope of simple formulaic protocols.  相似文献   
60.
以甘肃陇南地震滑坡体自然恢复过程中植被群落为研究对象,以坡面为尺度,采用样带结合海拔梯度的方法进行了调查。根据野外调查资料,应用生物多样性的原理和方法分析了甘肃陇南地震滑坡体自然恢复5 a后植被群落结构特征及多样性空间分布的变化情况。结果表明试验区内主要植物以菊科和禾本科植物为主,群落垂直结构明显,大体分为3层;该群落中一年生草本植物种类最多,是该群落中处于优势地位的生活型;在7个样地中,随着海拔升高,Shannon-Wiener多样性指数(H′)的变化趋势和Pielou均匀度指数(E)的变化趋势基本相同,均呈现先增大后减小的单峰趋势,Margalef丰富度指数(R)和Simpson优势度指数(C)表现出基本相同的变化趋势,均表现出先减小后增大再减小的偏峰格局势,峰值偏向高海拔区。  相似文献   
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