959 resultados para Landscape ecology -- Catalonia -- Alt Empordà -- 1957-2001


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The Second National Workshop on Marine Mammal Research and Monitoring in the National Marine Sanctuaries was held on 28 November 1999 in Maui, Hawaii. The workshop preceded the Thirteenth Biennial Conference on the Biology of Marine Mammals, and provided an opportunity to review and promote marine mammal research and monitoring in the National Marine Sanctuaries (NMS). The purpose of the workshop was to bring together researchers and sanctuary staff and to improve marine mammal research and monitoring throughout the sanctuaries. Discussion topics included: potential multi-sanctuary projects, sources of funding for multi-sanctuary projects, services and equipment for researchers through the sanctuaries, consolidating small levels of funding, help in funding and support for writing up data, publishing documents in Technical Memoranda, and letters of support. Representatives from the NMS national office and nine sanctuaries provided participants with overviews of marine mammal research within the sanctuaries. Presentations were also given by representatives from the National Marine Fisheries Service’s Permits and Health and Stranding programs. During the breakout working groups, there were several comments and suggestions consistent among each of the groups to improve marine mammal research. Each group emphasized the need to improve communication among researchers and to better share data. These suggestions included web-based information networks, advisory panels, and workshops. Regionally based research projects were also emphasized. In order to best study marine mammal populations, collaborative studies must take place throughout multiple sanctuaries. In order to achieve these large scale studies, funding and staffing must be directed towards these studies and distributed among each of the sanctuaries so that they may all be able to have the staffing, equipment, and vessels necessary to achieve a collaborative, ecosystem-based, regional marine mammal monitoring program. It will take several years to achieve all of the suggestions from the workshop, but thanks to the workshop participants, the National Marine Sanctuary Program has begun to direct marine mammal research and monitoring in order to achieve the goals of the workshop. This document provides a summary of the workshop with a focus on key points/main issues. We have included contact information intended to encourage continued collaboration among the individuals and organizations represented at the 1999 Marine Mammal Research and Monitoring in the National Marine Sanctuaries Workshop. (PDF contains 71 pages.)

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This report reviews marine zoning in the Monterey Bay National Marine Sanctuary (MBNMS). The 72 zoned areas in the MBNMS are of 13 different zone types. Each marine zone type has associated regulations that restrict or promote specific activities. For example, recreational activities such as boating, fishing, tidepooling, snorkeling, and SCUBA diving are limited in some zones. Scientific research is allowed at all sites, with appropriate permits, and is specifically promoted in a few sites. In addition, motorized personal watercraft use, dredge material disposal, large vessel traffic, jade collection, and aircraft overflight are allowed only in specific zones. The effectiveness of the marine zoning in the MBNMS is difficult to determine for two reasons. Firstly, many of the zones lack a clearly stated purpose or have confusing regulations. Secondly, the majority of the zones have not been evaluated formally by the managing agencies. Of the zones that have been evaluated, such as Dredge Material Disposal zones, Big Creek MRPA Ecological Reserve, and Pt. Lobos State/Ecological Reserve, the majority appear to be achieving their mandated purpose to some extent. Many of the zones in the MBNMS fall under the title "marine reserve." Marine reserves have recently received significant attention internationally, nationally, and in California due to their potential for: improving the status of exploited species; protecting marine habitats and ecosystems from degradation; facilitating scientific research and fisheries management; and increasing ecotourism. However, reserves must be well designed and managed to reach this potential. A well designed and managed reserve will have clearly defined goals, scientifically-based design, proper enforcement of regulations, rigorous evaluation of the reserve's effectiveness, and adaptive management. Based on these criteria, the majority of the marine reserves in California are not well designed or managed. However, the State of California has recognized this problem and is in the process of re-evaluating the California system of marine managed areas. (PDF contains 137 pages.)

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(PDF contains 3 pages.)

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This study analyzed species richness, distribution, and sighting frequency of selected reef fishes to describe species assemblage composition, abundance, and spatial distribution patterns among sites and regions (Upper Keys, Middle Keys, Lower Keys, and Dry Tortugas) within the Florida Keys National Marine Sanctuary (FKNMS) barrier reef ecosystem. Data were obtained from the Reef Environmental Education Foundation (REEF) Fish Survey Project, a volunteer fish-monitoring program. A total of 4,324 visual fish surveys conducted at 112 sites throughout the FKNMS were used in these analyses. The data set contained sighting information on 341 fish species comprising 68 families. Species richness was generally highest in the Upper Keys sites (maximum was 220 species at Molasses Reef) and lowest in the Dry Tortugas sites. Encounter rates differed among regions, with the Dry Tortugas having the highest rate, potentially a result of differences in the evenness in fishes and the lower diversity of habitat types in the Dry Tortugas region. Geographic coverage maps were developed for 29 frequently observed species. Fourteen of these species showed significant regional variation in mean sighting frequency (%SF). Six species had significantly lower mean %SF and eight species had significantly higher mean %SF in the Dry Tortugas compared with other regions. Hierarchical clustering based on species composition (presence-absence) and species % SF revealed interesting patterns of similarities among sites that varied across spatial scales. Results presented here indicate that phenomena affecting reef fish composition in the FKNMS operate at multiple spatial scales, including a biogeographic scale that defines the character of the region as a whole, a reef scale (~50-100 km) that include meso-scale physical oceanographic processes and regional variation in reef structure and associated reef habitats, and a local scale that includes level of protection, cross-shelf location and a suite of physical characteristics of a given reef. It is likely that at both regional and local scales, species habitat requirements strongly influence the patterns revealed in this study, and are particularly limiting for species that are less frequently observed in the Dry Tortugas. The results of this report serve as a benchmark for the current status of the reef fishes in the FKNMS. In addition, these data provide the basis for analyses on reserve effects and the biogeographic coupling of benthic habitats and fish assemblages that are currently underway. (PDF contains 61 pages.)

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The workshop was organized to understand and describe the livelihoods of poor people who manage aquatic resources for planning support. The purpose was to support field workers to carry out livelihood analysis and how to use this information. (PDF contains 13 pages)

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(PDF contains 3 pages.)

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(PDF contains 4 pages.)

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alt="" hspace="8" width="149" height="210" align="left" />目录

第一部分总论

环境流体力学――它的意义,内容与方法 李家春

用于大气环流模式的陆面物理过程参数化研究进展 戴永久,曾庆存,欧阳兵

植被-陆面过程耦合模式的动力框架 欧阳兵

第二部分均匀下垫面的陆面过程

干旱地区陆面过程的研究 李家春,姚德良,沈卫明

阿克苏地区陆面蒸发的数值研究 沈卫明,姚德良,李家春

塔里木盆地陆气水热交换数值模拟 姚德良,沈卫明,李家春

植物固沙区土壤水热运移耦合模型研究 姚德良,李家春,沈卫明

Numerical simulation of watercycling and heat balance in agricultural ecosystems D.L.Yao,W.M.Shen and J.C.Li

在植物耗水条件下土壤水分动态的数值模拟 姚德良,邱克俭,冀伟,孙菽芬

干旱地区陆面过程耦合模式及其应用 李家春,姚德良,沈卫明

Modelling of terrestrial ecosystem B.Ouyang

森林生态系统生物循环过程的耦合模型(BCM)及其数值模拟 欧阳兵

森林生态系统生物能流的瞬态分析 欧阳兵

第三部分非均匀下垫面的陆面过程

Turbulence in the atmosphere and ocean J.C.Li

非均匀下垫面上大气边界层的研究进展 徐大鹏

非均匀植被的群体蒸发 徐大鹏

第四部分 区域尺度以上的陆面过程与水文模型

Sensitivity of IAP two-level AGCM to surface albedo variations Z.H.Lin,Q.C.Zeng and B.Ouyang

估算区域蒸发的能量法研究 聂松媛,徐丰

用卫星数据估算区域水资源蒸发研究 聂松媛

负轮分析法在水环境规划与管理中的应用 聂松媛

第五部分 陆面过程观测的指标体系

Mathematical modelling and index system in ecology J.C.Li

陆面过程的观测指标体系研究 欧阳兵,李家春,姚德良

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alt="" hspace="6" width="200" height="260" align="left" />本文集共收录了作者24篇期刊论文和研究报告。其中,1943~1955年期间发表的14篇论文内容涉及直管中的可压缩流动、有限振幅柱面和球面波的传播、可压缩流体二维无旋亚声速、超声速混合型流动和上临界马赫数、光滑跨声速绕流及其稳定性、斜激波从平板边界层的反射、中等雷诺数下绕平板的流动等。1956~1957年期间发表的5篇论文:绕平板和楔的高超声速流动、普朗特数和解离对高超声速流动的影响以及增补的5篇文章是作者在高超声速流动领域的研究成果以及他在回国后的学术报告和发表的文章,涉及现代空气动力学的发展方向、发射卫星和返地回收的科学和技术问题,体现了他在参与“两弹一星”技术领导工作中的学术思想。
目录
1 On the force and moment acting on a body in shear flow(物体在剪切流中所受的力和力矩1943年)
2 The flow of a compressible viscous fluid through a straight pipe.(可压缩黏性流体在直管中的流动1943年)
3 Two dimensional irrotational mixed subsonic and supersonic flow of a compressible fluid and the upper critical Mach number(可压缩流体二维无旋亚声速和超声速混合型流动及上临界马赫数1946年)
4 On the stability of transonic flows(论跨声速流的稳定性1947年)
5 The propagation of a spherical or a cylindrical wave of finite amplitude and the production of shock waves(有限振幅球面波或柱面波的传播及激波的产生1947年)
6 Two-dimensional irrotational transonic flows of a compressible fluid(可压缩流体二维无旋跨声速流动1948年)
7 On the hodograph method(关于速度图方法1949年)
8 Two-dimensional transonic flow past airfoils(绕翼型的二维跨声速流1951年)
9 On the stability of two-dimensional smooth transonic flows(论二元光滑跨声速流的稳定性1951年)
10 On the flow of an incompressible viscous fluid past a flat plate at moderate Reynolds numbers(中等雷诺数下不可压缩黏性流体绕平板的流动1953年)
11 Reflection of a weak shock wave from a boundary layer along a flat plate.I:Interaction of weak shock waves with laminar and turbulent boundary lavers analyzed by momentum-integral method(弱激波从沿平板的边界层的反射Ⅰ:用动量积分方法分析弱激波与层流和湍流边界层的相互作用1953年)
12 Reflection of weak shock wave from a boundary layer along a flat plate.Ⅱ:Interaction of oblique shock wave with a laminar boundary layer analyzed by differential-equation method(弱激波从沿平板的边界层的反射Ⅱ:用微分方程方法分析斜激波与层流边界层的相互作用1953年)
13 Plane subsonic and transonic potential flows(平面亚、跨音速势流1954年)
14 A similarity rule for the interaction between a conical field and a plane shock(锥型流和激波相互作用的相似律1955年)
15 Viscous flow along a flat plate moving at high supersonic speeds(沿高超声速运动平板的黏性流动【Ⅰ】1956年)
16 Viscous flow along a flat plate moving at high supersonic speeds(沿高超声速运动平板的黏性流动【Ⅱ】1956年)
17 The effects of Prandtl number on high-speed viscous flows over a flat plate(Prandtl数对绕平板高速黏性流的影响1956年)
18 Compressible viscous flow past a wedge moving at hypersonic speeds(楔的高超声速可压缩黏性绕流1956年)
19 Dissociation effects in hypersonic viscous flows(高超声速黏性流动中的离解效应1957年)
20 现代空气动力学的问题(1957年)
2l 在关于苏联发射成功第一颗人造卫星座谈会上的发言记录(1957年)
22 高超速钝体湍流传热问题(1963年)
23 宇宙飞船的回地问题(1965年)
24 激波的介绍
郭永怀生平
郭永怀传

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本书收录会议论文60篇。

  本书内容大体分为三类。一类着重介绍了钱学森先生的风范,他的爱国主义,他的勤奋好学,他的治学精神和治学态度,他在学术上的重大贡献以及他的科学思想。第二类是介绍在他的领导或影响下,五十年来我国力学研究取得的成就及进一步的进展。第三类涉及我国力学界正在开展的其他方面的学术研究进展。我们的共同目的是继承优良传统,开拓我国力学在新世纪的发展。

  读者对象:力学、航空航天、机械等领域的工程技术人员,研究人员。

会议论文
 
alt="" width="10" />学习钱学森先生技术科学思想的体会 郑哲敏;  
alt="" width="10" />国家目标与技术科学——钱学森的力学研究所建所思想 吴承康;  
alt="" width="10" />钱学森和中国空气动力研究与发展中心 焦安昌;钮颂镛;  
alt="" width="10" />钱学森教授与近代力学教育   
alt="" width="10" />钱学森开创的物理力学之路 朱如曾;  
alt="" width="10" />工程结构优化设计 钱令希;  
alt="" width="10" />压电类智能材料与结构的力学分析 余寿文;沈亚鹏;匡震邦;  
alt="" width="10" />一般力学(动力学、振动与控制)研究动态与发展趋势 黄文虎;胡超;  
alt="" width="10" />力学系统控制的几个问题 黄琳;  
alt="" width="10" />与物理分析相结合的计算流体力学 张涵信;庄逢甘;  
alt="" width="10" />烧蚀防热的非线性气固耦合 姜贵庆;  
alt="" width="10" />湍流的复杂系统论 佘振苏;程雪玲;  
alt="" width="10" />纳米力学进展 杨卫;郑泉水;方岱宁;黄克智;  
alt="" width="10" />从简单系统的定量分析到复杂巨系统的综合集成 庄逢甘;黄志澄;  
alt="" width="10" />关于力学研究的方法论问题 童秉纲;  
alt="" width="10" />哈密顿原理中时端条件的处理方法及其推广 刘高联;  
alt="" width="10" />ASYMMETRIC VORTEX FLOW OVER SLENDER BODIES 罗时钧;  
alt="" width="10" />亚、超声喷管中声传播的数值模拟 高军辉;李晓东;  
alt="" width="10" />格子Boltzmann数值流体力学 冯士德;毛江玉;任荣彩;  
alt="" width="10" />微型飞行器的仿生流体力学——昆虫产生高升力的机理 孙茂;唐剑;

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The Tortugas South Ecological Reserve, located along the margin of the southwest Florida carbonate platform, is part of the largest no-take marine reserve in the U.S. Established in July 2001, the reserve is approximately 206 km2 in area, and ranges in depths from 30 m at Riley’s Hump to over 600 m at the southern edge of the reserve. Geological and biological information for the Tortugas South Reserve is lacking, and critical for management of the area. Bathymetric surveys were conducted with a Simrad EM 3000 multibeam echosounder at Riley’s Hump and Miller’s Ledge, located in the northern and central part of the reserve. Resulting data were used to produce basemaps to obtain geological ground truth and visual surveys of biological communities, including reef fishes. Visual surveys were conducted using SCUBA and the Phantom S2 Remotely Operated Vehicle (ROV) at Riley’s Hump. Visual surveys were conducted using the ROV and the Deepworker 2000 research submersible along Miller’s Ledge, within and outside of the reserve. A total of 108 fishes were recorded during SCUBA, ROV, and submersible observations. Replicate survey transects resulted in over 50 fishes documented at Miller’s Ledge, and eight of the top ten most abundant species were planktivores. Many species of groupers, including scamp (Mycteroperca phenax), red grouper (Epinephelus morio), snowy grouper (E. niveatus), speckled hind (E. drummondhayi), and Warsaw grouper (E. nigritus), are present in the sanctuary. Numerous aggregations of scamp and a bicolor phase of the Warsaw grouper were observed, indicating the importance of Miller’s Ledge as a potential spawning location for both commercially important and rare deep reef species, and as a potential source of larval recruits for the Florida Keys and other deep reef ecosystems of Florida

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Marine Fishery Reserves (MFRs) are being adopted, in part, as a strategy to replenish depleted fish stocks and serve as a source for recruits to adjacent fisheries. By necessity, their design must consider the biological parameters of the species under consideration to ensure that the spawning stock is conserved while simultaneously providing propagules for dispersal. We describe how acoustic telemetry can be employed to design effective MFRs by elucidating important life-history parameters of the species under consideration, including home range, and ecological preferences, including habitat utilization. We then designed a reserve based on these parameters using data from two acoustic telemetry studies that examined two closely-linked subpopulations of queen conch (Strombus gigas) at Conch Reef in the Florida Keys. The union of the home ranges of the individual conch (aggregation home range: AgHR) within each subpopulation was used to construct a shape delineating the area within which a conch would be located with a high probability. Together with habitat utilization information acquired during both the spawning and non-spawning seasons, as well as landscape features (i.e., corridors), we designed a 66.5 ha MFR to conserve the conch population. Consideration was also given for further expansion of the population into suitable habitats.

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This study summarizes the results of a survey designed to provide economic information about the financial status of commercial reef fish boats with homeports in the Florida Keys. A survey questionnaire was administered in the summer and fall of 1994 by interviewers in face-to-face meetings with owners or operators of randomly selected boats. Fishermen were asked for background information about themselves and their boats, their capital investments in boats and equipment, and about their average catches, revenues, and costs per trip for their two most important kinds of fishing trips during 1993 for species in the reef fish fishery. Respondents were characterized with regard to their dependence on the reef fish fishery as a source of household income. Boats were described in terms of their physical and financial characteristics. Different kinds of fishing trips were identified by the species that generated the greatest revenue. Trips were grouped into the following categories: yellowtail snapper (Ocyurus chrysurus); mutton snapper (Lutjanus analis), black grouper (Mycteroperca bonaci), or red grouper (Epinephelus morio); gray snapper (Lutjanus griseus); deeper water groupers and tilefishes; greater amberjack (Seriola dumerili); spiny lobster (Panulirus argus); king mackerel (Scomberomorus cavalla); and dolphin (Coryphaena hippurus). Average catches, revenues, routine trip costs, and net operating revenues per boat per trip and per boat per year were estimated for each category of fishing trips. In addition to its descriptive value, data collected during this study will aid in future examinations of the economic effects of various regulations on commercial reef fish fishermen.(PDF file contains 48 pages.)

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Identification problems are common for many sharks due to a general lack of meristic characteristics that are typically useful for separating species. Other than number of vertebrae and number and shape of teeth, identifications are frequently based on external features that are often shared among species. Identification problems in the field are most prevalent when live specimens are captured and releasing them with a minimum of stress is a priority (e.g., shark tagging programs). Identifications must be accurate and conducted quickly but this can be challenging, especially if specimens are very active or too large to be landed without physical damage. This field guide was designed primarily for use during field studies and presents a simplified method for identifying the 21 species of western North Atlantic Ocean sharks belonging to the family Carcharhinidae (carcharhinids). To assist with identifications a dichotomous key to Carcharhinidae was developed, and for the more problematic Carcharhinus species (12 species), separation sheets based on important distinguishing features were constructed. Descriptive text and illustrations provided in the species accounts were developed from field observations, photographs, and published references. (PDF file contains 36 pages.)