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Long-term effects of clear-cutting and selective cutting on soil methane fluxes in a temperate spruce forest in southern Germany 总被引:1,自引:0,他引:1
Wu X Brüggemann N Gasche R Papen H Willibald G Butterbach-Bahl K 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2467-2475
Based on multi-year measurements of CH4 exchange in sub-daily resolution we show that clear-cutting of a forest in Southern Germany increased soil temperature and moisture and decreased CH4 uptake. CH4 uptake in the first year after clear-cutting (−4.5 ± 0.2 μg C m−2 h−1) was three times lower than during the pre-harvest period (−14.2 ± 1.3 μg C m−2 h−1). In contrast, selective cutting did not significantly reduce CH4 uptake. Annual mean uptake rates were −1.18 kg C ha−1 yr−1 (spruce control), −1.16 kg C ha−1 yr−1 (selective cut site) and −0.44 kg C ha−1 yr−1 (clear-cut site), respectively. Substantial seasonal and inter-annual variations in CH4 fluxes were observed as a result of significant variability of weather conditions, demonstrating the need for long-term measurements. Our findings imply that a stepwise selective cutting instead of clear-cutting may contribute to mitigating global warming by maintaining a high CH4 uptake capacity of the soil. 相似文献
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We applied the complex ecosystem model EMMO, which was adopted to the shallow lake Müggelsee (Germany), in order to evaluate a large set of ecological scenarios. By means of EMMO, 33 scenarios and 17 indicators were defined to characterize their effects on the lake ecosystem. The indicators were based on model outputs of EMMO and can be separated into biological indicators, such as chlorophyll-a and cyanobacteria, and hydro-chemical indicators, such as phosphorus. The question to be solved was, what is the ranking of the scenarios based on their characterization by these 17 indicators? And how can we handle high quantities of complex data within evaluation procedures? The scenario evaluation was performed by partial order theory which, however, did not provide a clear result. By subsequently applying the hierarchical cluster analysis (complete linkage) it was possible to reduce the data matrix to indicator and scenario representatives. Even though this step implies losses of information, it simplifies the application of partial order theory and the post processing by METEOR. METEOR is derived from partial order theory and allows the stepwise aggregation of indicators, which subsequently leads to a distinct and clear decision. In the final evaluation result the best scenario was the one which defines a minimum nutrient input and no phosphorus release from the sediment while the worst scenario is characterized by a maximum nutrient input and extensive phosphorus release from the sediment. The reasonable and comprehensive results show that the combination of partial order, cluster analysis and METEOR can handle big amounts of data in a very clear and transparent way, and therefore is ideal in the context of complex ecosystem models, like that we applied. 相似文献
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Rainer Brüggemann Gerhard Ginzel Christian Steinberg 《Environmental Sciences Europe》1997,9(6):339-343
Conflict are frequently observed when drinking water protection areas are to be defined and when many variants of how to protect these area are to be found. Using ten potential scenarios, a method is presented here which shows how such conflicts concerning these variants may be handled in a systematic manner. The technique is derived from the use of partially ordered sets and their visualization by Hasse diagrams. The first step is to define rankings of different variants according to each aim of protection. A further step is to define an appropriate relationship of order. It is then possible to visualize the extent of consensus and of dissension through the use of a Hasse diagram. The final step is to quantify the importance of each protection aim and the initialization of an iteration. Should a complete consensus be found, this would result in a chain of (connected) variants. Should a complete dissension be found on the other hand, an antichain would then result (i.e. where all variants are isolated). 相似文献
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Stefan Pudenz Rainer Brüggemann Kristina Voigt Gerhard Welzi 《Umweltwissenschaften und Schadstoff-Forschung》2003,15(1):20
Zur Unterstützung von Bewertungs- und Entscheidungsprozessen über die Nachhaltigkeit von Managementstrategien, deren Auswirkungen
durch unterschiedlich dimensionierte Indikatoren gemessen werden, gibt es verschiedene mathematische Methoden. In diesem Beitrag
werden die Prinzipien dieser sog. multikriteriellen Bewertungs- und Entscheidungshilfeinstrumente beispielhaft anhand einer
Auswahl von Strategien für ein Nachhaltiges Wassermanagement vorgestellt, sowie Vor- und Nachteile herausgearbeitet. Es wird
gezeigt, dass sich die Verfahren insbesondere in Transparenz, Objektivit?t und durch den Grad an Partizipation durch Akteure
z.T. erheblich unterscheiden. W?hrend die Hassediagrammtechnik sich an den naturwissenschaftlich begründbaren Datenmatrix
orientiert und somit eine objektive und transparente Bewertung und Datenanalyse liefert, haben Konkordanzanalyse, Nutzwertanalyse,
PROMETHEE und AHP ihre St?rken in der M?glichkeit, Akteure bzw. Stakeholder am Entscheidungsprozess partizipieren zu lassen.
*** DIRECT SUPPORT *** A00OI029 00003 相似文献
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