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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2012

2011

Abstract

Spatial dependencies among environmental variables are often quantified by spatial autocorrelation functions. The latter basically assume linearity and isotropy, requirements usually not satisfied for measured data. Typical symptoms of violated assumptions are biased parameter estimations. Relaxing the assumptions of linear dependencies and isotropy, we present a conceptual generalization of spatial analysis where locally varying anisotropies in the geographical space are uncovered by investigating nonlinear dependencies among observations. The framework is illustrated by generalizing two examples: distance decay relations and spatial filtering. The proposed alternative is based on geodesic ecological and anisotropic spatial distances.

Abstract

Based on intensive forest monitoring data, critical loads for acidification and eutrophication as well as their exceeedances were modelled for 107 Level II plots using the simple mass balance approach. Dynamic modelling using the VSD model was carried out for 77 plots using different deposition scenarios.Results show widespread soil acidification in the year 1980 with nearly 60% of the plots affected by critical load exceedances. A continued positive future development until 2020 is clearly visible, leading to full protection at least under the most ambitious deposition scenario.Critical loads for nutrient nitrogen were exceeded on 60% of the plots in 1980 and continue to be so in 2020 on between 10 and 30% of the plots depending on the scenario. Dynamic modelling shows that soil solution pH can recover to pre-industrial values but that over the all the 77 plots the C:N ratio shows a continuous decrease until 2050.A comparison with to measured solid soil pH from large scale plots confirms recovery for acidified soils until 2008 but shows increased acidification on soils with pH above 4.0. and points to the fact that full recovery from acidification will take decades. Decreasing C:N and continued exceedance of critical loads for nutrient nitrogen point to soil eutrophication as a major and continued area of concern.