水利水电工程扰动区景观生态廊道构建方法研究

阐述了水利水电工程扰动区面临的生态环境问题,针对问题提出了通过构建景观生态廊道,恢复水利水电工程扰动区生态系统结构和服务功能的原则和方法。将水利水电工程扰动区景观生态廊道设计为5种类型:防护林生态廊道、滨水岸线生态廊道、道路生态廊道、修复区连接廊道、自然景观生态廊道。详细探讨了各种景观生态廊道具体构建内容和布局,为规划和建设绿色大坝提供了一个比较新颖的构建方法。     

城市河流景观格局及可持续生态策略研究

基于景观生态学原理构建了数字化城市河流廊道-斑块格局,并与自然格局进行了类比评价分析.结合城市干扰性、景观资源空间差异性等定性分析,实现了城市河流景观格局的耦合评价;通过景观格局指数的生态袁征敏感性的探讨和河流景观格局指数与生态效应的关联性分析,提出了河流景观生态格局的优化策略.     

黄河下游滩地以林为主综合开发研究

针对黄河下游滩区面临的河床抬升、水旱灾害、水体污染、蝗虫危害及土地退化等一系列生态环境问题,分析了以林为主综合开发黄河下游滩地的科学性。指出以林为主综合开发黄河下游滩地符合生态学规律,能有效地利用好小浪底水库建成后创造的有利时机,充分发挥森林提高生产力、保护和改善生态环境等多重功能,推动黄河下游滩区协调发展。以林为主综合开发必须坚持生态优先、科技支撑、综合协调和开发的整体性。     

南水北调东线工程沿线城市尾水处理方案比选

以洪泽县为例,综合运用水文学和生态学等理论和方法,研究南水北调东线工程沿线城市尾水处理方案的选择,最终确定蓄水塘-廊道-兼性塘-表面流湿地组合的尾水处理方案,并建议将处理工艺与景观建设相结合,建成集生态、景观、休闲、科教等功能于一体的综合性示范工程。     

辐射井技术在滨州市黄河滩地地下淡水资源开发中的应用

对滨州市城区饮用水源现状进行了分析,针对滨州市用水现状论述了合理开发利用地下淡水资源的必要性。详细地分析、计算了地下淡水资源合理开发利用的取水方式、产水量,并对黄河滩地地下水开发利用方式可行性及效益进行了分析。     

基于景观格局变化评价的梯级水电开发规划方案研究

根据景观生态学理论,借助地理信息系统工具,采用定量的方法分析工程景观格局状况,通过建立水电开发建设规划方案的景观格局变化评价的指标体系和评价方法,研究水电开发规划方案对区域景观格局的影响。本方法应用于黄河上游黑山峡河段水电开发建设方案析分析。结果表明：不同规划方案实施后对原有生态环境均产生了一定影响。通过对不同方案与研究区域生态现状进行灰色关联分析,红山峡、五佛、小观音和大柳树4个坝址均修建低坝的方案的景观格局指数最高,研究区域景观生态风险最小。最终确定该方案为最优方案,该方案对区域原有生态体系性质和功能影响较小。     

黄河下游生态水量调度实践

为全面推进水生态环境保护和修复,2016—2018年开展了黄河下游生态流量调度试点工作,研究黄河下游河道生态功能维持和生态服务需求的流量指标,实施生态水量调度。以2018年黄河下游生态水量调度为例,分析生态调度实践情况。在确定了生态水量调度目标及原则的基础上,对生态水量调度方案以及生态水量调度效果进行了分析,结果表明:黄河下游生态水量调度实践有效增加了入海淡水资源量,提高了生态流量满足程度,进一步增加了下游湿地面积,维持和改善了河道生态廊道功能,促进了水生生境的保护与修复。     

城市水域生态格局的内涵及作用机制

城市水域是城市景观的重要生态廊道,其功能的正常实现与否关系到整个城市的可持续发展,科学判别并维护城市水域生态格局具有重要战略意义。基于景观生态学理论,从地理学视角探讨城市水域生态格局的科学内涵,辨析城市水域的自然基底类型,阐释城市水域格局与城市发展的相互作用机制。结果表明:城市的自然环境条件、历史文化传统是影响城市水域生态格局形成和演变的重要驱动因素,城市水域生态格局对城市用地布局、公共空间以及景观轴线具有明显导向作用。科学剖析并构建城市水域生态格局,可为城市规划、建设和管理提供重要的技术支撑。在此基础上,对厦门市水域生态格局进行优化调控。     

格宾石笼在生态堤防工程中的适用性分析

生态护岸是现代河道治理发展的趋势,格宾石笼应用在堤防工程中,实现了传统堤防向生态堤防的转型,保留了河流原有的结构和作为生态廊道的功能。本文对格宾石笼适用于堤防的特性、堤防的结构设计,以及应用中需注意的问题进行了较为详细的分析论述。     

景观生态学在城市水土保持规划中的应用

随着城市化进程的加快,我国城市水土流失的问题日益严重。城市水土保持工作是实现城市可持续发展的基础。本文从城市水土保持与景观生态学的内涵入手,论述了景观结构与功能、景观异质性和生物多样性、景观动态变化与景观安全格局等理论在城市水土保持规划中的应用,从理论与实践上指出了景观生态学理论对城市水土保持规划的指导意义。     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.     

浙江省水域调查录入系统的设计和应用

浙江省水域调查录入系统将调查数据与电子地图相整合,对分类水域数据进行统计计算,并对输入数据进行合理性和完整性检查,得到调查范围内现有水域的详细数据,实现了水域调查数据输入、计算、统计和查询的数字化管理,提高了工作效率和工作质量,为各地下阶段水域保护规划编制和水域管理工作提供了数据支持。对该系统的设计原则、功能和技术设计等作了介绍。     

基于CT-连续加荷水泥乳化沥青混凝土细观损伤规律研究

利用CT技术对水泥乳化沥青混凝土的细观损伤过程进行实时扫描观测,获得了混凝土试件在连续加荷下的CT图像。通过采用直观分析法、CT数分析法、CT数与损伤变量关系3种方法分析表明,水泥乳化沥青混凝土的破坏过程可分为压密、扩容、裂纹扩展、破坏4个阶段,同时混凝土在受压过程中具有韧性,在极限荷载之前各断面处于压密和微扩容的强化阶段,极限荷载之后混凝土从损伤到破坏发展比较平稳。     

浅谈天湖水电站水轮机运行故障及处理措施

简述天湖水电站投运以来各种故障的表现形式，分析其原因，提出了相应的处理方法及措施，并对合理利用国内外设备提出建议。     

Fish assemblage response to recent mitigation of a channelized warmwater stream

Various designs of low‐head dams are used to rehabilitate streams or forestall upstream channel incision after channelization. We report on the efficacy of using notched sills and grade control structures (GCS) to restore the fish assemblage in Luxapallila Creek, Mississippi. We tested the null hypotheses that habitat variables and species richness, evenness, and assemblage structure would not differ among: (1) a channelized segment with no modifications; (2) a channelized segment mitigated by the installation of sills and GCS; (3) a segment upstream of the installations and undergoing channel incision; and (4) an unaltered segment. Although habitat variables changed, neither species richness, evenness, nor fish assemblage structure differed between mitigated and channelized segments with both exhibiting less richness and different assemblage structures than the unaltered segment. Lack of differences in species richness between the incised and unaltered segments suggest that the GCS may have halted the negative effects of upstream channel incision before species were extirpated. Conspicuous habitat differences between the altered (channelized and mitigated) and unaltered segments were lack of backwaters and canopy coverage and finer substrates in the altered segments. Our results suggest a more comprehensive rehabilitation strategy is required in Luxapallila Creek. Published in 2003 by John Wiley & Sons, Ltd.     

NUMERICAL STUDY OF WAVE EFFECTS ON SURFACE WIND STRESS AND SURFACE MIXING LENGTH BY THREE-DIMENSIONAL CIRCULATION MODELING

1. INTRODUCTION Coastal and continental shelf regions are characterized by intensive interaction between wave and current. These regions are of great economic significance to mankind. Therefore, the modeling of wave and current as well as their mutual int…