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1.
水文水资源学家陈守煜先生学术研究的知识图谱分析 总被引:3,自引:0,他引:3
为探索水文水资源学家陈守煜先生学术研究历程及其演变规律,以其335篇文献作为数据基础,采用共现分析等文献计量可视化分析方法,通过文献发表的时间分布、学科和期刊分布、高被引文献分布和研究主题等方面的知识图谱分析,系统分析了陈先生的学术研究历程。结果显示:陈守煜先生学术研究生命周期历时达62年,在其60岁后出现了2个学术创新高峰期;其学术研究特色荟萃于其河渠非恒定流计算、模糊集理论的水文水资源应用、模糊水文水资源学基本理论、模糊聚类-识别-优选统一理论、可变模糊集理论和可变模糊集理论的水文水资源应用6个研究主题,其中主题1为后续的5个模糊水文水资源学创新主题奠定了数值计算的研究方法论,主题2为模糊集现有理论的应用探索,主题3至主题5为面向工程应用的模糊集理论不断深入创新,主题6为可变模糊集理论的应用探索,形成了"紧密结合应用-持续理论创新-创新理论再应用"这种理论与实践互馈的研究特色。他每一阶段的研究目标比较集中、明确,与其研究主题密切对应,显著提高了研究效率;他的学术研究影响广泛,合计被引8554次,缘于他的源头理论创新。陈先生的研究,理论与应用不断互馈,贵在厚积薄发、深入钻研、持续创新,其研究理念和方法论,对水利科学的学术创新研究具有重要的启示作用和深远影响。 相似文献
2.
3.
海绵城市雨水花园水文水质过程模拟 总被引:1,自引:0,他引:1
以宜兴市中心某区域为例,通过参数率定及模型验证,构建了研究区域的SWMM模型,研究了不同重现期(3、10、50、100年)下,雨水花园水文、水质变化情况。结果表明,重现期3~100年条件下,平均径流量、峰值流量、平均径流系数、入渗量、污染物SS负荷总量、COD负荷总量、TN负荷总量、TP负荷总量分别降低11.65%~12.66%、6.82%~8.46%、21.33%~23.26%、22.42%~22.81%、8.98%~10.08%、8.73%~9.84%、7.83%~9.09%、6.36%~8.33%,雨水花园可有效降低平均径流量、峰值流量、平均径流系数,增加入渗量,对污染物SS、COD、TN、TP的负荷总量也有较好的控制效果,为一种有效的海绵措施,且不受降雨重现期大小的影响,呈较为固定的范围。 相似文献
4.
改革开放以来,浙中地区在特定的经济、社会背景下,已逐步发展成以多中心为主要特征的城乡融合的浙中城市群。通过分析浙中城市群的特征、问题、背景和机制,明晰在强县扩权体制背景下、在"温州模式"的经济模式下,县域强中心、区域多中心的城乡融合发展模式的优越性。指出应将"小的是美好的"作为未来浙中城市群空间引导的核心理念,在浙江人多地少的宏观条件下引导城市空间的有机集聚,通过"TOD模式与串珠状发展空间、绿核与优质生活圈"等战略措施实现"城乡融合、整体融合"的空间引导目标。 相似文献
5.
This study presents the relationship between the dam hydrology and phytoplankton proliferations in a regulated river system in East Asia. A long-term ecological study reveals that multi-purpose dam regulation on river flow in the Nakdong River (South Korea) affects proliferating patterns of phytoplankton, especially during summer (June-August) and winter (December-next February) as Microcystis aeruginosa and Stephanodiscus hantzschii, respectively, dominate each season by over 80%. Eutrophication was observed in the lower Nakdong River (South Korea) (mean+/-standard deviation: nitrate-N, 2.8+/-0.9 mg L(-1); phosphate-P, 40.3+/-31.3 microg L(-1); chlorophyll a, 45.2+/-84.9 microg L(-1); n=449), and the limnological characteristics responded to climatic variations such as monsoon and summer typhoons. The river basin experiences concentrated rainfall during the rainy season (June-September, over ca. 60% of total annual rainfall). Correlation and cross-correlation for time-delayed relationship revealed the hydrological environments (i.e., quantity of dam storage and discharge) had significantly negative relationship with the population dynamics of the two bloom-forming species for up to the next 2 years. S. hantzschii had clearer relationship with dam storage and discharge, which might be due to the seasonality exhibited by the species. The results support the necessity of "smart flow control" which may enable destruction of bloom formation by the two species with an adequate pulse of discharge generated by upstream dams in the far-east Asian river systems. This would increase the efficiency of water resource management system. 相似文献
6.
从地形、地质条件、气侯、水文条件、土壤、植物覆盖等方面阐述了自然条件对路线的影响,并记述了公路对水、土壤、气侯等自然环境的影响作用,从而使自然因素与路线的相互作用向着良性循环的方向发展,以确保公路安全、迅速、经济、舒适和自然环境的良好。 相似文献
7.
Basset-Mens C Anibar L Durand P van der Werf HM 《The Science of the total environment》2006,367(1):367-382
The challenge for environmental assessment tools, such as Life Cycle Assessment (LCA) is to provide a holistic picture of the environmental impacts of a given system, while being relevant both at a global scale, i.e., for global impact categories such as climate change, and at a smaller scale, i.e., for regional impact categories such as aquatic eutrophication. To this end, the environmental mechanisms between emission and impact should be taken into account. For eutrophication in particular, which is one of the main impacts of farming systems, the fate factor of eutrophying pollutants in catchments, and particularly of nitrate, reflects one of these important and complex environmental mechanisms. We define this fate factor as: the ratio of the amount of nitrate at the outlet of the catchment over the nitrate emitted from the catchment's soils. In LCA, this fate factor is most often assumed equal to 1, while the observed fate factor is generally less than 1. A generic approach for estimating the range of variation of nitrate fate factors in a region of intensive agriculture was proposed. This approach was based on the analysis of different catchment scenarios combining different catchment types and different effective rainfalls. The evolution over time of the nitrate fate factor as well as the steady state fate factor for each catchment scenario was obtained using the INCA simulation model. In line with the general LCA model, the implications of the steady state fate factors for nitrate were investigated for the eutrophication impact result in the framework of an LCA of pig production. A sensitivity analysis to the fraction of nitrate lost as N(2)O was presented for the climate change impact category. This study highlighted the difference between the observed fate factor at a given time, which aggregates both storage and transformation processes and a "steady state fate factor", specific to the system considered. The range of steady state fate factors obtained for the study region was wide, from 0.44 to 0.86, depending primarily on the catchment type and secondarily on the effective rainfall. The sensitivity of the LCA of pig production to the fate factors was significant concerning eutrophication, but potentially much larger concerning climate change. The potential for producing improved eutrophication results by using spatially differentiated fate factors was demonstrated. Additionally, the urgent need for quantitative studies on the N(2)O/N(2) ratio in riparian zones denitrification was highlighted. 相似文献
8.
从变化与发展的角度,探讨了快速城市化背景下现代景观设计的思潮与挑战,剖析了中国现代景观存在的问题,运用生态学原理构建针对问题的生态思维模型即景观视觉设计、文脉设计、环境保护与开发以及公众参与过程的生态思维。并以大连市童牛岭风景区南部入口为例论述该模型的构建与应用:通过因子分析法选择主导因子进行多元景观方案的设计,运用公众参与和Delphi法对3个方案进行评价,结果表明方案2视觉效果显著、文脉突出,环境影响小,成本合理;方案1和3分别以文化和环境为主导因子,但前者成本较低,后者成本较高,因此,三者优秀率依次 相似文献
9.
J. Tranter BSc C. Hunter BSc PhD J. Gunn BSc PhD J. Perkins BSc PhD 《Water and Environment Journal》1996,10(4):273-279
Faecal coliform concentrations were determined at stream and water inflow sampling sites within an upland catchment in North Derbyshire containing rough, semiimproved and improved pastures. The results indicated that, during its passage through the catchment, the faecal indicators of the stream increased, and this may constitute a health risk to cavers using a popular recreational cave into which the stream drains. The decline in streamwater quality suggests that a semipermanent store of bacteria existed in catchment soils, and hydrological processes operated to transfer bacteria from the land to the stream channel. Contrary to expectations, intra-catchment differences in the bacterial quality of water at inflow and stream sampling sites could not be related to the intensity of agricultural land use in adjacent areas. This is explained with reference to changes in the nature of hydrological transport pathways associated with the improvement of pastures. 相似文献
10.
G. H. Old PhD G. J. L. Leeks BSc J. C. Packman MSc N. Stokes MSc N. D. Williams MSc B. P. G. Smith PhD E. J. Hewitt MSc S. Lewis MSc 《Water and Environment Journal》2004,18(1):11-16
Urban watercourses are potential hazards because of their rapid flow changes, poor water quality and contaminated sediments. This study is a preliminary field investigation into fine sediment-associated metal contamination and its transport dynamics in a highly urbanised catchment in West Yorkshire, UK. Spatial and temporal changes in the concentration of channel-bed sediment-associated metals are investigated, and the fluxes of selected suspended sediment-associated metals, during an extreme high flow event, are determined. Channel-bed sediments were more contaminated at the most heavily urbanised sites. Data suggest that contaminated bed sediments could accumulate and possibly become increasingly contaminated between high-flow events, prior to being flushed from the system. Fluxes of contaminated suspended sediments were very high at the peak of the high flow event. The spatial and temporal dynamics of contaminated fine sediment which were identified in this study could inform planners with regard to future monitoring strategies. 相似文献