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71.
《Journal of Great Lakes research》2022,48(6):1681-1695
Interspecific interactions among walleye Sander vitreus, lake whitefish Coregonus clupeaformis, and yellow perch Perca flavescens in Green Bay could influence the population status of each species, but potential trophic interactions are poorly understood. Our objectives were to determine if diet assemblages for each species and diet overlap among species varied spatially and temporally within Green Bay. Adult walleye (≥381 mm total length (TL); N = 981), lake whitefish (≥432 mm TL; N = 1507), and yellow perch (≥150 mm TL; N = 1174) were collected during May-October of 2018 and 2019 from multiple locations in southern and northern Green Bay. Diet assemblages of each species varied between northern and southern Green Bay, but walleye diets were more temporally variable (among months within zones and between years) than diets of lake whitefish or yellow perch. Lake whitefish represented a seasonally important prey item for walleye in southern Green Bay, composing 10 % and 41 % of walleye diets by weight in May and June, respectively. Yellow perch generally composed <15 % of walleye diets by weight but were consumed at a broader spatiotemporal scale than lake whitefish. Diet overlap between walleye and both lake whitefish and yellow perch was generally weak or moderate, whereas diet overlap between whitefish and perch was generally strong. Our assessment of adult trophic interactions suggests that changes in the population status of one species could influence fisheries for all three, and we identify additional research questions to address potential population-level effects of these trophic interactions. 相似文献
72.
Daodi Flood Land, located in Mentougou District of Beijing, is a relatively separate flood land in the lower reaches and on the east of Yonding River. This largest landscape character area in the west of Beijing along the river illustrates the history of human–water interaction and discloses the trends and problems of rural urbanization. Focusing on Daodi Flood Land, this paper expands the research on adaptation by introducing basic concepts and research framework, and reviews the research trends from spatial, temporal, and participant aspects. Considering the typical characters of the study area, this research employed participatory approaches, such as mapping and problem and solution trees, due to the lack of continuous and accurate data. Basing on literature review and field investigation on issues of floods, agricultural irrigation, and water resource utilization, water adaptive development visions for the study area were proposed from perspectives of landscape and culture. Finally, the paper further analyzes the structural relations between adaptation problems, natural and social systems, passive and active adaptations, and planned and unplanned adaptations, with the aim to provide reference for relevant studies and applications of adaptation approaches in other cases. 相似文献
73.
Dongdong Feng Dawei Guo Yijun Zhao Heping Tan Guozhang Chang Tianpeng Zhang Shaozeng Sun 《能源学会志》2019,92(6):1670-1682
Oxygen-fuel combustion is a promising technology for CO2 emission reduction. The high-temperature entrained flow reactor and high-temperature drop tube furnace were used to analyses the formation and O2/CO2 combustion characteristics of real-environment coal char in high-temperature oxy-fuel conditions. It proposed “inflection point standard” of high-temperature flame method for the preparation of real-environmental oxy-fuel coal char according to the flame method. The results show that the ratios of C=O/C-O and C=O/Car increase in the coal char compared with the raw coals. The trend of C=O/Car in oxy-fuel condition is opposite to that in the inert atmosphere, due to the effect of high-concentration CO2. To achieve the burnout rate similar to air combustion for coal char, with the increase of coal rank, the O2 concentration should be enhanced. The optimal O2 concentration for the oxy-fuel combustion of JC anthracite is 30%, while that of other low-rank coals could be lower than 30%. The combustion characteristic of JC anthracite is with the highest sensitivity to temperature and O2 concentration. 相似文献
74.
水利遗产是人类文化遗产的重要组成部分。近年来
中国众多水利遗产已逐步纳入城市建成区范围,水利遗产的主
导功能也由生态、生产为主逐步转向多功能兼容。但水利遗产
的核心价值及可持续运行的关键还没有得到充分阐释。福州西
湖至今已有1 700余年历史,经历了22次疏浚,逐步从官湖
转变为公园、从城郊型湖泊转变为城市中的湖泊,是典型的
“活着的”“转型中的”水利遗产。借鉴景观多功能性理论,
通过民国《西湖志》文本与图示解析,从人类福祉角度探讨福
州西湖水利遗产景观主导性与多样性在空间中的关系,梳理不
同利益相关主体之间的博弈关系及其对西湖水利可持续运行的
影响。以期揭示水利遗产景观多功能性的时空演进过程、构建
水利遗产“景观-功能-管理”的级联关系,为推动城市水利遗
产从景观多功能性走向景观可持续性提供参考。 相似文献
75.
《Cities》2014
Berlin is a German city and federal state, situated in the heart of Europe. It has been the capital city since 1991, and is the largest city in the country with around 3.4 million inhabitants. This profile explains Berlin’s historical development and emphasizes changes which took place during the 20th century (the Weimar period in the 1920s, followed by the Nazi takeover in 1933 and the city’s destruction during World War II, then the division of the city into West Berlin and East Berlin, until its final reunification in 1990 after the Wall fell down). After reunification, Berlin experienced a new period of urban redevelopment in which many new buildings were constructed. This profile also outlines some recent positive changes in terms of Berlin’s economic growth and its transformation into the capital of innovative new companies in the digital, culture and media industries. 相似文献
76.
Richard Garber 《Architectural Design》2016,86(1):120-127
The dissolution of the conventional breaking points in the construction and completion phases of a building's delivery has blurred ‘the distinction between the production of design intent and the transmission of information’. Here Richard Garber , Director of the School of Architecture at the New Jersey Institute of Technology (NJIT), advocates that architects should use this as an opportunity to widen their remit, gaining agency and with it responsibility and the financial rewards to practice. Here he draws from the examples of UNStudio, GLUCK+ and his own New-York based practice, GRO Architects. 相似文献
77.
78.
Felicity D Scott 《Architectural Design》2015,85(3):78-85
Felicity D Scott , Associate Professor of Architecture at Columbia University Graduate School of Architecture, Planning and Preservation (GSAPP), describes here the instant city events of the early 1970s. These foreshadowed current global village media practices in what now seems a quaintly material manner: communication between sites involved the physical mailing of videotapes and ‘wire photos’ through the postal service. The sites themselves – in the US and elsewhere – were transformed into ‘instant cities’ through the erection of physical geodesic domes, teepees and inflatables in seas of mud. The true antecedents of today's instant networking, these pioneers embraced the newest technology available at the time and the most innovative forms of temporary architecture. 相似文献
79.
通过对文脉主义建筑的概念辨析,以自然组织符号、都市组织符号以及群体组织符号的体系划分,强调对建筑创作中有关自然环境、城市文化,以及建筑系统指涉信息的"原初性"识别,并以此分析当代西方建筑符号所具备的新兴审美特征。 相似文献
80.
民国时期先后作为首都和陪都的南京、武汉、重庆,同属长江流域,具有类似的地理环境,其时兴建的民国建筑,开创了我国传统建筑吸收西方技术开展城市设计的先河。三地又依城市所处环境不同而保持了各自的地域建筑特色,这为当下提供了有益的借鉴:既要传承历史,又要合理吸收西方先进设计理念,同时兼顾自然地理环境和市场需求,以建设具有中国特色的城市文化。 相似文献