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A New Coastal Marine Ecosystem Model Study Coupled with Hydrodynamics and Tidal Flat Ecosystem Effect 总被引:3,自引:0,他引:3
Akio Sohma Yasuyuki Sekiguchi Hiroshi Yamada Tatsuaki Sato Kisaburo Nakata 《Marine pollution bulletin》2001,43(7-12):187-208
A new coastal marine ecosystem model was developed, which was composed of pelagic and benthic ecosystems, and was applied to Mikawa Bay, Japan. This model deals with variations of biochemical and physical interactions among dissolved oxygen and C–N–P species (composition formed out of carbon, nitrogen and phosphorus elements) so that it resolves the flux dynamics of carbon, nitrogen, phosphorus and oxygen elements. The physical and biochemical mechanism figured in this model is constructed for the purpose of simulating the estuarine lower trophic ecosystem, in areas where the sea was too deep for light to reach the sea-bottom. As a result of coupling the benthic with pelagic system, the effect of process of sedimentation and nutrient diffusion back to the pelagic system could be indicated. In addition, by implementing the tidal flat ecosystem model's calculation result, the integrated model can include the effect of water purification in tidal flats where the light can reach the sea-bottom, and where sea-weed, sea grass and benthic algae exist. In this study, the model indicates that oxygen-depleted water exists at the sea-bottom especially in summer mainly caused by an increase of oxygen consumption in the benthic system and a decrease of the vertical mixing water process. Furthermore, by comparing the case – with the tidal flat ecosystem model and the case without it, the effect of water purification of tidal flat estuaries was indicated. From the viewpoint of a short time scale, the tidal flat has the potential to restrict red tide (rapid increase of phytoplankton), and from the viewpoint of a long time scale, it restricts the sedimentation of detritus. Restricting the sedimentation prevents oxygen-depleted water occurring in the coastal marine system of Mikawa Bay. 相似文献
254.
Pollani Annika Triantafyllou George Petihakis George Nittis Konstantinos Dounas Costas Christoforos Koutitas 《Marine pollution bulletin》2001,43(7-12):270-278
In this work the development and the application of an operational management tool for the Greek Seas is described. This tool consists of a three-dimensional floating pollutant prediction model coupled with a weather, a hydrodynamic and a wave model in order to track the movements and the spreading of the pollutants and indicate those coastal areas which might be affected. The tool is part of the Poseidon system which has been designed to provide real time data and forecasts for marine environmental conditions in the Greek Seas. In this paper, we present four case studies based on realistic scenarios that show the value of the application for long-term strategic planning and short-term decision making in oil spill accidents. 相似文献
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Roland Otto 《Hydrogeology Journal》2001,9(5):498-511
In the southeastern Holstein region, located to the east of the metropolitan zone of Hamburg, northern Germany, a groundwater
investigation program was conducted from 1984 to 2000 by the State Agency for Nature and Environment (Landesamt für Natur
und Umwelt, LANU) of Schleswig-Holstein, Germany, with the aim of providing long-term, ecologically acceptable groundwater
management plans for the region. The focal point of the investigation comprised the determination of groundwater recharge
rates. The investigation method was based on the transfer of available lysimeter results from other regions to comparable
regions within the area studied. With the help of lysimeter equations, potential amounts of percolation water were calculated.
The groundwater recharge rate was then determined after subtraction of the surface runoff which was calculated for the entire
area. All computations were performed with a spreadsheet program. Groundwater recharge rates were calculated for two areas.
One consisted of roughly determining groundwater recharge rates for the total region (1,392 km2) of southeastern Holstein. The overall goal of these investigations was to identify potential areas of water exploitation.
Areas in which groundwater recharge rates are high and groundwater outflow is low are particularly suited to water exploitation,
since inflow rates into deeper aquifers are high. These areas are located on the flanks of the Elbe and Stecknitz River valleys.
Subsurface groundwater runoff to these lowlands would be reduced through groundwater withdrawal. However, the resulting decline
in shallow groundwater tables would be so small that it would have no detrimental ecological effects. Groundwater recharge
rates were also calculated for a 110-km2 area in the outskirts of Hamburg (Grosshansdorf model area) which is intensively developed for water supply. These investigations
showed that the amount of groundwater recharge is already being withdrawn to a large extent. Approximately 65% of the recharge
rate is currently withdrawn by the waterworks in this area, thus making further increases in exploitation rates unjustifiable
from an ecological point of view.
Electronic Publication 相似文献
257.
Won Bae Kim 《GeoJournal》2001,53(1):47-56
The historic summit between the leaders of the two Koreas in June 2000 provided a new opportunity for inter-Korean dialogue. Despite many uncertainties regarding the form and substance of inter-Korean economic cooperation, Korean people believe that inter-Korean economic cooperation will expand and eventually lead to economic and territorial integration of the two Koreas. This essay discusses the progress and issues of inter-Korean economic cooperation including infrastructure development. In particular, the essay examines long-term planning issues surrounding the territorial integration of the Korean peninsula and their implications for balanced development. With the German case of economic integration as a point of reference, the essay points out a few strategic problems involved in inter-Korean economic cooperation and suggests an alternative strategy to achieve balanced development. 相似文献
258.
Yong-Woong Kim 《GeoJournal》2001,53(1):5-15
In the early stages of economic development in Korea, national territorial planning was used as a policy tool to guide spatial structure and to provide physical infrastructure for urban and industrial development. Such a top-down approach was inevitable because Korea maintained the centralized political and government system until the early 1990s. Circumstances, however, have changed recently since the 1990s with progress in democratization and localization. In addition, forces of globalization are making significant impacts on the parameters of national territorial planning. Reflecting these changes in both internal and external conditions, the Fourth National Territorial Plan (2000–2020) has adopted a different approach from the past three territorial plans. This paper reviews the socio-economic background that necessitated such changes in approaches to national territorial planning. A major thrust of the Fourth Plan, a focus on emergent or anticipated planning issues in Korea, is discussed. Finally, the paper examines the rationale for long-term strategic planning in the highly fluctuating situation facing Korean society in the new century. 相似文献
259.
Martin Gast Wolfgang Schaaf Joerg Scherzer Rudolf Wilden Bernd U. Schneider Reinhard F. Hüttl 《Journal of Geochemical Exploration》2001,73(2):196
To analyze the development of pine ecosystems on lignite and pyrite containing mine soils, four pine stands with ages of 3–35 years were investigated in a chronosequence approach. Bulk precipitation, throughfall and soil solution in depths of 20, 40, 70 and 100 cm were studied over a three-year period to determine element fluxes in these forest ecosystems on extreme acidic and saline soils.Element budgets are controlled by the processes induced by pyrite oxidation such as intensive weathering of primary minerals, precipitation and leaching of secondary phases.Despite low water fluxes, element outputs can reach extraordinary high values due to very high concentrations in the soil solution. Although element outputs decrease drastically with stand age, respectively, site age, they exceed those of comparable pine stands on non-mine sites. Nitrogen release from the lignite fraction represents a special characteristic of the examined substrates. Nitrogen losses beneath the rooted zone can be 34 kg N ha−1 yr−1 in 100 cm depth. Element input and output in the examined ecosystems are far from balance. Closed cycling of nutrients seems to be recognizable in the case of potassium. 相似文献
260.