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51.
杭州湾大桥建设与宁波城市的发展 总被引:1,自引:0,他引:1
杭州湾跨海大桥即将动工建设 ,本文分析了大桥建成后对宁波市社会经济和城市空间结构的影响 ,认为大桥建设将会提高宁波市在长江三角洲城市群中地位 ,促进宁波市成为上海市后方工业基地。城市空间结构将会出现质的跨越 ,城市中心东移 ,甬江开发利用开始起动。 相似文献
52.
Titus S. Seilheimer Patrick L. Zimmerman Kirk M. Stueve Charles H. Perry 《Journal of Great Lakes research》2013
The Great Lakes watersheds have an important influence on the water quality of the nearshore environment, therefore, watershed characteristics can be used to predict what will be observed in the streams. We used novel landscape information describing the forest cover change, along with forest census data and established land cover data to predict total phosphorus and turbidity in Great Lakes streams. In Lake Superior, we modeled increased phosphorus as a function of the increase in the proportion of persisting forest, forest disturbed during 2000–2009, and agricultural land, and we modeled increased turbidity as a function of the increase in the proportion of persisting forest, forest disturbed during 2000–2009, agricultural land, and urban land. In Lake Michigan, we modeled increased phosphorus as a function of ecoregion, decrease in the proportion of forest disturbed during 1984–1999 and watershed storage, and increase in the proportion of urban land, and we modeled increased turbidity as a function of ecoregion, increase in the proportion of forest disturbed during 2000–2009, and decrease in the proportion softwood forest. We used these relationships to identify priority areas for restoration in the Lake Superior basin in the southwestern watersheds, and in west central and southwest watersheds of the Lake Michigan basin. We then used the models to estimate water quality in watersheds without observed instream data to prioritize those areas for management. Prioritizing watersheds will aid effective management of the Great Lakes watershed and result in efficient use of restoration funds, which will lead to improved nearshore water quality. 相似文献
53.
Tana V. McDaniel Pamela A. Martin Glenn C. Barrett Kim Hughes Andrée D. Gendron Lenny Shirose Christine A. Bishop 《Journal of Great Lakes research》2009
Little is known of mudpuppy (Necturus maculosus) population structure and ecology; some populations in the Great Lakes are thought to be in decline. Mudpuppies are the obligate hosts for the mudpuppy mussel (Simpsonaias ambigua), a species that is endangered in Canada and in many Great Lakes states. We surveyed mudpuppies from the Sydenham River, the only known Canadian locality of the mudpuppy mussel, in order to generate information on relative density, deformity rates and population age/size structure and used this information to compare them to known mudpuppy populations from Great Lakes sites in the Detroit River, Lake St. Clair and Long Point in Lake Erie. Deformity rates were elevated at some sites in the Sydenham River. The relative density of mudpuppies in the Sydenham River was lower than that of other Great Lakes sites and their age was skewed towards younger individuals. Although at lower densities than at other Great Lakes sites, the mudpuppy population in the Sydenham River appears stable and is showing signs of recruitment which bodes well for the future of the mudpuppy mussel population of the river. 相似文献
54.
Fish have been shown to be sensitive indicators of environmental quality in Great Lakes coastal wetlands. Fish composition also reflects aquatic macrophyte communities, which provide them with critical habitat. Although investigators have shown that the relationship between water quality and fish community structure can be used to indicate wetland health, we speculate that this relationship is a result of the stronger, more direct relationship between water quality and macrophytes, together with the ensuing interconnection between macrophyte and fish assemblages. In this study, we use data collected from 115 Great Lakes coastal marshes to test the hypothesis that plants are better predictors of fish species composition than is water quality. First we use canonical correspondence analysis (CCA) to conduct an ordination of the fish community constrained by water quality parameters. We then use co-correspondence analysis (COCA) to conduct a direct ordination of the fish community with the plant community data. By comparing the statistic ‘percent fit,’ which refers to the cumulative percentage variance of the species data, we show that plants are consistently better predictors of the fish community than are water quality variables in three separate trials: all wetlands in the Great Lakes basin (whole: 21.2% vs 14.0%; n = 60), all wetlands in Lakes Huron and Superior (Upper: 20.3% vs 18.8%; n = 32), and all wetlands in Georgian Bay and the North Channel (Georgian Bay: 18% vs 17%; n = 70). This is the largest study to directly examine plant–fish interactions in wetlands of the Great Lakes basin. 相似文献
55.
为掌握城市河网动态水环境容量变化规律,构建了基于“空-地-水”一体化模型体系的城市河网动态水环境容量计算模型,以粤港澳大湾区惠州市金山湖流域为研究区域,定量核算了2017年金山湖流域COD和TP动态水环境容量。结果表明,模型模拟的流量、COD和TP浓度率定、验证的相对误差均在14.04%以内;2017年,金山湖流域COD和TP水环境容量整体呈先增大后减小的趋势,受降雨影响显著,逐日容量变化范围分别为238.55~3 027.49 kg/d和3.73~58.02 kg/d;枯水期水环境容量较小且与降水量负相关;丰水期的大雨或暴雨时期水环境容量明显提升,中小雨时期COD容量与降水量负相关,TP反之;保障生态基流能明显改善容量不足的问题,全年动态生态流量保障对金山湖流域水质达标率提升效果明显。 相似文献
56.
《Soils and Foundations》2014,54(4):902-909
The Great East Japan Earthquake and its accompanying liquefaction and tsunami severely damaged many sewage systems including sewage pipes, manholes, pumping stations and sewage treatment plants over a wide area from Tohoku to the Kanto region. We conducted a questionnaire survey, interview survey and on-site confirmation in order to summarize and categorize the damage factors that shut down facilities such as drainage systems and treatment systems. We also studied the effectiveness of countermeasures to prevent liquefaction of the sewage system. The results showed that 90% of sewage pipes and 70% of manholes were damaged by liquefaction and that 54% of wastewater treatment plants and 75% of pumping stations were damaged by tsunami. Nevertheless, no severe damage was found along sewage pipe sections where liquefaction countermeasures had been executed, suggesting that the countermeasures are effective. 相似文献
57.
求解理想的住宅——“建筑师走廊”给出的答案 总被引:1,自引:0,他引:1
本文通过对“亚洲建筑师走廊”中建筑的环境、空间、材料、色彩的评论,探讨对理想的个性化居住建筑的理解。 相似文献
58.
59.
以循环经济理念推进西部大开发 总被引:6,自引:0,他引:6
孙宝强 《成都纺织高等专科学校学报》2005,22(1):22-23,26
推进西部大开发需要牢固树立和全面落实科学发展观,实现可持续发展.循环经济是突破西部地区可持续发展能力瓶颈的最佳选择.大力发展循环经济要学习借鉴国外经验,成立专门领导机构,制定和落实循环经济发展规划,扩大宣传;抓紧制定有关的地方法规和促进政策;确立重点行业,科学引导,加快示范和推广. 相似文献
60.
Xiaobo Chao Yafei Jia Charles M. Cooper F. Douglas Shields Jr. Sam S. Y. Wang 《Canadian Metallurgical Quarterly》2006,132(11):1498-1507
A three-dimensional numerical model was developed for simulating the phosphorus concentration in shallow lakes. In this model, the computational domain was divided into two parts: the water column and the bed sediment layer. The processes of mineralization, settling, adsorption, desorption, bed release (diffusion), growth, and death of phytoplankton were taken into account, and the concentration of organic phosphorus, phosphate, and related water quality constituents was simulated. The concentrations of adsorbed (particulate) and dissolved phosphate due to adsorption-desorption were calculated using two formulas derived based on the Langmuir equation. The release rate of phosphorus from the bed sediment layer was calculated by considering the effects of the concentration gradient across the water-sediment interface, pH, temperature, dissolved oxygen concentration, and flow conditions. The adsorption and desorption of phosphate from sediment particles, as well as its release from bed sediment, were verified using laboratory experimental data. The model was calibrated and applied to Deep Hollow Lake in the Mississippi alluvial plain. The simulated trends and magnitudes of phosphorus concentration were compared with field observations. The simulation results show that there are strong interactions between sediment-related processes and phosphorus concentration. 相似文献