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Pieterse N. M. Verkroost A. W. M. Wassen M. Olde Venterink H. Kwakernaak C. 《Landscape Ecology》2002,17(1):69-81
Despite efforts that have been put into conservation, there is a continuing loss of species and ecosystems in Western Europe. There is a growing awareness that restoration is an essential step to stop this tide. Unfortunately, there is lack of understanding about the multitude of functions and the complexity of spatial interactions in a landscape. The focus of this paper is to demonstrate that an Integrated Decision Support System (IDSS) is indispensable to offer insight in this complexity and to design efficient restoration programmes. The IDSS is applied in a lowland catchment on the border between The Netherlands and Belgium and leads to the following recommendations: (1) The site conditions on the location where restoration is planned must be close to the range that is required for the target ecosystem. (2) The manager has to decide for the most attainable targetecosystem, and accept the inevitable loss of other ecosystems as a result from this choice. (3) Restoration planning involves that the optimal measure for each catchment, subcatchment or region is assessed, being ecological, urban or agricultural. (4) For each ecosystem an optimal set of measures must be selected. An analysis of the restoration efficiency (ecological gain divided by economic costs) is crucial for this selection. 相似文献
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N.M.?PieterseEmail author H. Olde?Venterink P.P.?Schot A.W.M.?Verkroost 《Landscape Ecology》2005,20(6):743-753
There is an ongoing debate as to whether nutrient contamination of groundwater under agricultural fields may cause nutrient-enrichment
and subsequent eutrophication in discharge areas. Often, there is only circumstantial evidence to support this supposition
(proximity of agricultural fields, direction of water flow, highly productive vegetation). Research on solute transport along
a flow path is necessary to evaluate the risk for eutrophication. In this paper we present results of such a study. Two transects
were established in a discharge meadow, a few meters downstream from fertilized cornfields. Highly productive vegetation in
parts of the meadow suggested nutrient-enrichment caused by inflow of contaminated groundwater. This supposition was supported
by an analysis of groundwater flow paths, residence times and chloride as tracer for pollution. However, the fate of nutrients
along the flow path indicated otherwise. While we found high concentrations of DIN (dissolved inorganic nitrogen), P and K
under the cornfields, DIN and P concentrations drop below detection limit when groundwater enters the meadow. Only K progressed
into the meadow but did not enter the root zone. We conclude that (1) polluted groundwater from the cornfields did not cause
the nutrient-enrichment, as indicated by the highly productive vegetation. Restoration projects in discharge areas should
not focus upon measures in upstream areas if only circumstantial evidence is available. Solute transport should be considered
as well. (2) Because K clearly showed to be the most mobile nutrient, its importance for nutrient-enrichment in discharge
wetlands merits more attention in future research. 相似文献
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