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1.
Exchanges of total N and C between a river and its floodplain forest have been enhanced by sedimentation processes during flood pulses at a 5‐ha bottomland hardwood forest located at the Olentangy River Wetland Research Park in central Ohio. In the spring of 2000, the forest was hydrologically restored by notching an artificial levee that had separated the Olentangy River and its floodplain forest for 100 years. One‐hundred flat sediment traps (30 cm × 30 cm) were used to collect sediment samples during spring/summer flooding events from 2003 to 2005. Results showed that sediment deposition is determined by the landscape variability during flooding events, Net sediment deposit in the wettest area averaged 134 ± 12 g‐dry wt m?2 in 2003, 127 ± 17 g‐dry wt m?2 in 2004 and 149 ± 23 g‐dry wt m?2 in 2005. Total N and C sedimentation ranged from 0.49 to 0.92 g‐N m?2 and 5.2 to 19.9 g‐C m?2. Fe dominates the sediment chemistry and results show the elemental abundance in the order of Al > Fe > Ca > K > Mg > S > P > Na > Mn > Zn > B > Cu > Mo. A hydrologic pulsing index (HPI) could be used as an indicator for mass changes of energies with hydrologic pulsing events. Restoration of seasonally flooded bottomland forests could stimulate potentially large nutrient and Fe releases, which would eventually lead to an enhanced forest productivity and biodiversity. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
2.
梅瑶炯 《中国园林》2006,22(4):39-44
合肥市政务文化新区儿童乐园的概念性方案,充分考虑了儿童的心理和成长交流需要,以儿童的自发活动为特色,兼顾各类活动设施,创造丰富活动空间,构筑了一个富有感染力、空间变幻多彩的都市儿童乐园.  相似文献   
3.
空间的塑造--厦门海湾公园设计   总被引:1,自引:1,他引:0  
海湾公园利用植物、地形、大海与湖泊的周边环境等景观要素,运用隐喻、对比的手法,创造丰富、神秘、变化的空间,注重空间灵活的使用功能及其良好的人性化.  相似文献   
4.
The U.S. Fish and Wildlife Service uses the term palustrine wetland to describe vegetated wetlands traditionally identified as marsh, bog, fen, swamp, or wet meadow. Landsat TM imagery was combined with image texture and ancillary environmental data to model probabilities of palustrine wetland occurrence in Yellowstone National Park using classification trees. Model training and test locations were identified from National Wetlands Inventory maps, and classification trees were built for seven years spanning a range of annual precipitation. At a coarse level, palustrine wetland was separated from upland. At a finer level, five palustrine wetland types were discriminated: aquatic bed (PAB), emergent (PEM), forested (PFO), scrub-shrub (PSS), and unconsolidated shore (PUS). TM-derived variables alone were relatively accurate at separating wetland from upland, but model error rates dropped incrementally as image texture, DEM-derived terrain variables, and other ancillary GIS layers were added. For classification trees making use of all available predictors, average overall test error rates were 7.8% for palustrine wetland/upland models and 17.0% for palustrine wetland type models, with consistent accuracies across years. However, models were prone to wetland over-prediction. While the predominant PEM class was classified with omission and commission error rates less than 14%, we had difficulty identifying the PAB and PSS classes. Ancillary vegetation information greatly improved PSS classification and moderately improved PFO discrimination. Association with geothermal areas distinguished PUS wetlands. Wetland over-prediction was exacerbated by class imbalance in likely combination with spatial and spectral limitations of the TM sensor. Wetland probability surfaces may be more informative than hard classification, and appear to respond to climate-driven wetland variability. The developed method is portable, relatively easy to implement, and should be applicable in other settings and over larger extents.  相似文献   
5.
闫家瑞 《古建园林技术》1988,(18):17-18转21
福禄宫位于湖南长沙市城西区,始建于清代光绪年间。解放后,福禄宫因未及时修理维护,朽损情况严重,1983年底被拆毁。通过对残留木制装修构件拼凑,推算出该建筑的蝼蜂窠部分测绘图。福禄宫蝼蜂窠类似于北方斗栱中的平身科,是一种装饰性构件。福禄宫的昂嘴采用翼龙飞凤交错排列的形式,部分昂嘴端部另加雕饰花板。蝼蜂窠采用层层叠置出踩的形式,其表面只施以桐油或光油等透明涂料,未施其它色漆及彩绘。  相似文献   
6.
7.
带控制结构的物流园区平面布置法   总被引:1,自引:0,他引:1  
物流园区的规划是个世界范围的新课题,尤其在物流园区设施规划方面理论和经验更是欠缺。对系统化设计法(SLP)做了改进,提出了带控制结构的物流园区总平面布置法。该方法把选址区外部交通设施作为控制点或控制线,与内部功能分区一起进行关联分析,外部控制结构和内部关联关系同时作为布置搜索线进行内部功能区位置构建。该方法的优点是体现了园区内部平面布置和外部交通设施的互动,并通过扬州城北物流园区的应用实例,取得了较好的效果。  相似文献   
8.
工业是株洲的特色所在,株洲工业园区经过二十多年的发展,取得了长足的进步,但同时也存在着转型压力很大、造血功能不强、发展后劲不足、发展环境不优等问题。因此,株洲工业园区要实现升级发展,必须突出园区的集聚效应,以大园区集聚大产业,以大项目推动大集群,以大招商谋划大发展,以大服务构筑大环境。  相似文献   
9.
奥林匹克公园中心区雨洪利用示范工程的建立,将雨洪控制与利用纳入到实际建设,采用规模化的雨洪利用系统,建设雨洪利用示范工程,以展示城市雨水排放新概念,实现雨水资源化.对于中心区地表径流水质进行检测,深入研究和分析,科学的展示了雨洪利用示范工程的科学性和合理性,让人们对雨水利用的意义有直观认识,了解简单易行的雨水利用技术,...  相似文献   
10.
In the recent years, industrial clusters have received considerable attention from economists and industrial analysts, because they are seen as the main reason for economic growth and success of certain economic region. This study systematically reviews past researches of industrial cluster. The purpose of this paper is to contribute to the understanding of this issue regarding the driving forces for the growth of industrial cluster and find out the priority among these cluster policies. Taiwan HsinChu Science Park is a prime example for this paper, and its connection with the innovative participators. We begin with an examination of the literature on cluster about its driving forces and policies upon which we propose a conceptual framework. In doing so, we explore the cluster-based industrial system. Then this research adopts the Fuzzy Analytic Hierarchy Process as the analytical tool. The Fuzzy Analytic Hierarchy Process method is used to determine the weightings for evaluation dimension among decision makers. From our research results, the Factor Conditions is the most important driving force for advancing the industrial cluster performance. Moreover, the promotion of international linkages policy and broader framework policies rank the first two priorities for cluster policy. Overall, this paper concludes with some simulations of cluster policy alternatives confronting the industry and the Taiwanese government.  相似文献   
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