Comparison of models and lattice-gas simulations for Liesegang patterns

For more than a century Liesegang patterns -- self-organized, quasi-periodic structures occurring in diffusion-limited chemical reactions with two components -- have been attracting scientists. The pattern formation can be described by four basic empirical laws. In addition to many experiments, several models have been devised to understand the formation of the bands and rings. Here we review the most important models and complement them with detailed three-dimensional lattice-gas simulations. We show how the mean-field predictions can be reconciled with experimental data by a redefinition of the distances suggested by our lattice-gas simulations.Comment: 21 pages, 9 figures, accepted for publication in EPJ Special Topic

Prospects for climate friendly peatland management – Results of a socioeconomic case study in Germany

In the current debate on climate protection, agricultural production has become a focal point of interest. This study introduces the climate effectiveness of agricultural management of peat-soils. Agriculture on peatland demands a water-level drawdown that causes aerobe degradation of the soils. The resulting trace-gas emissions have a negative impact on the greenhouse-gas balance. In Germany more than 80% of peatland is used agriculturally; the resulting emissions account for 2.3 – 4.5% of Germany’s overall emission. Climate-friendly peatland management strategies, however, demand enhanced groundwater tables and decreased land-use intensity. With regard to agricultural income, severe economic consequences are to be expected. Against this background we analyse opportunities to reorganise agricultural use of peatland. As it is assumed that the potential to reduce land-use intensity greatly depends on local socio-economic conditions which are likely to vary across different regions, six representative sample regions are surveyed. To analyse microeconomic effects with simultaneous consideration of local diversity, stakeholder workshops and extensive farm surveys were undertaken in all regions. First results indicate that a reorganisation of peatland use causes severe loss of agricultural income and necessitates financial compensation for farmers. However the results also show that the potential of rearrangement varies significantly according to regional conditions.agricultural peatland use, reduction of greenhouse gases, farm survey, economic consequences, Land Economics/Use, Q24, Q54, R58,

Integrating Ecological And Economic Aspects In Land Use Concepts: Some Conclusions From A Regional Land Use Concept For Bayerisches Donauried

Land use concepts for ecologically particularly sensitive agricultural landscapes are often focussed on the attainment of specific environmental objectives in specific areas, neglecting both socio-economic effects, in particular income effects, and the farmers' income-driven production responses outside these areas. The paper illustrates, on the basis of an empirical study on the land use in the southern German region Bayerisches Donauried, (1) that the farmers' objectives and production responses need to be integrated in land use concepts for agricultural landscapes because of their potentially counterproductive effects on the attainment of environmental objectives, and (2) how multi-criteria analysis (MCA) can be used to transform a primarily ecology-oriented land use concept for an ecologically very sensitive agricultural landscape into a more comprehensive one that makes due allowance for the farmers responses and society's socio-economic objectives. The authors show that such integration of socioeconomic objectives can contribute to the maintenance of incomes and employment without overly harming the attainment of ecological goals. As far as the MCA is concerned, two methods are applied: The linear-additive model, and the outranking model ELECTRE. The models serve to evaluate four different land use options. Nine criteria are used, derived from the relevant landscape functions. Weights are based on written interviews with major decision-makers, and stakeholders of the region. The major assumptions underlying the models are discussed. The authors interpret the results of each model on the basis of sensitivity analyses, and compare them. Finally, the paper discusses policy implications resulting from the implementation of land use concepts for agricultural landscapes, in particular the question of a regionalisation of agri-environmental policy, and raises some administrative and practical issues that come up if policy makers apply MCA more widely in the design of such concepts.Land Economics/Use,

New responsibilities of agriculture: structural differences in stakeholder networks and intentions towards climate change abatement strategies in peatland

Agriculture is required to fulfil the needs and wants of society in a variety of fields: food supply, environmental services, landscape preservation and finally: climate mitigation. Using the example of land-use change in peatland in order to create possibilities for greenhouse-gas reduction, a survey about the intentions and future expectations of stakeholders was undertaken. The underlying network structure of these stakeholders in three representative peatland areas of Germany was determined and compared. The results show that considerable differences exist in the degree of knowledge about climate change and in the willingness to cooperate. Depending on the area studied, the most influential political entities are different and thus require different strategies for agenda setting. From the study it can be concluded, that the realisation of a political or societal goal, for example greenhouse-gas reduction, relies largely on the intentions among the stakeholders and structural differences in the stakeholder networks. Our example has shown that for these reasons, land-use change for climate protective reasons will be supported more in the study-area in the South of Germany in comparison to the case in the eastern part.Land-use in peatland areas, network analysis, climate change mitigation., Land Economics/Use, D83, D85, L31, Q54.,

Integrating Multifunctionality of Agriculture in Regional Land Use Concepts

Because of high population density in Europe agriculture cannot define its aims on its own but has to take account of quite a number of demands from different actors. For instance, agriculture is expected to produce food and at the same time to contribute to the protection of cultural landscapes and the maintenance of ecological services. However, land use concepts are often formulated ecology-oriented neglectingsocio-economic objectives and potential production responses of farmers. The present paper is aimed to illustrate how multi-criteria analysis can be used to transform a primarily ecology-oriented land use concept for an ecologically very sensitive region into a more integrative and comprehensive one that makes due allowance for socio-economic objectives and farmers' response. The results of our study show that production responses of farmers decisively influence the utility society obtains from land use. Multi-criteria analysis helps to assess the trade-off between 'ecology' and 'economy' and shows how the integration of socio-economic objectives can contribute to the maintenance of incomes and employment without overly harming the attainment of ecological objectives. Our results clearly suggest which farmer production responses should be supported by private organisations and government bodies. Consequently the results can serve as a basis for a local policy programme and can thereby contribute to a regionalisation of agri-environmental measures.multi-criteria analysis, multifunctionality of agriculture, regional land-use concepts, Land Economics/Use, Q21, Q51, Q59, R0,

Integrating ecological and economic aspects in land use concepts for agricultural landscapes

Especially in environmentally sensitive agricultural landscapes, agriculture cannot define its aims by itself - it has to account for a number of demands of different groups of society. For example, agriculture is expected to produce food and at the same time contribute to the protection of cultural landscapes and to further ecological services. Land use concepts for ecologically particularly sensitive agricultural landscapes are often focussed on the attainment of specific environmental objectives in specific areas, neglecting both socioeconomic effects, in particular income effects, and the farmers' income-driven production responses outside these areas. The paper illustrates, on the basis of an empirical study, (1) that the farmers' objectives and production responses need to be integrated in land use concepts for agricultural landscapes because of their potentially counterproductive effects on the attainment of environmental objectives, and (2) how multi-criteria decision analysis (MCDA) can be used to transform a primarily ecology-oriented concept for an ecologically very sensitive agricultural landscape into a more comprehensive one that makes due allowance for the farmers’ responses and society's socio-economic objectives. The authors show that the integration of socio-economic objectives can contribute to the maintenance of incomes and employment without overly harming the attainment of ecological goals. Finally, the paper discusses policy implications resulting from the implementation of land use concepts for agricultural landscapes, in particular in the field of agri-environmental policy, and raises some practical issues that come up if policy makers apply MCDA more widely in the design of such concepts.agricultural landscapes, land-use concepts, multi-criteria decision analysis, Land Economics/Use, Environmental Economics and Policy,

Is non-Gaussianity sufficient to produce long-range volatile correlations?

Scaling analysis of the magnitude series (volatile series) has been proposed recently to identify possible nonlinear/multifractal signatures in the given data [1-3]. In this letter, correlations of volatile series generated from stationary first-order linear feedback process with Gaussian and non-Gaussian innovations are investigated. While volatile correlations corresponding to Gaussian innovations exhibited uncorrelated behavior across all time scales, those of non-Gaussian innovations showed significant deviation from uncorrelated behavior even at large time scales. The results presented raise the intriguing question whether non-Gaussian innovations can be sufficient to realize long-range volatile correlations.Comment: 17 Pages, 6 Figures, Physica

Impact of the CAP reform on small-scale grassland regions

This paper presents a regional land-use model that conceives farms as independent agents aiming at maximum individual utility. Farm agents optimize their utility with the help of a linear-programming algorithm that takes into account natural, economic and personal restrictions. Interactions between farms take place on the land market, which is modelled as an equilibrium market. The model is applied in three typical grassland regions in southern Bavaria. The results indicate that the CAP reform of 2003 has various significant consequences for grassland use. In particular, the decreasing profitability of dairy farming will lead to low-intensity forms of grassland use, including mulching. In general, land rents will increase due to the effects of decoupling.CAP Reform, linear programming, land-market simulation, agent-based modelling, farmers attitude, policy analysis, Agricultural and Food Policy, Land Economics/Use,

Structural Change and Landscape Appearance

Our study examines the potential developments of cultural landscapes, taking into consideration various economic and social conditions (scenarios). The study takes place in three project regions which represent typical landscapes in Southern Germany and Austria. In each project area, the influence of a changing economic and political framework is analysed. The following scenarios are defined: (1) status quo (current economic and agri-political framework); (2) high-producer prices and constant (or even increasing) direct payments; and (3) low-producer prices and no (or very low) direct payments. In all three regions, potential production responses are estimated for all farms and aggregated on a regional level. The estimation takes into account social and economic parameters such as cash flow, size and type of farms, age of farmers and workload. The results show that the impact of the changing agro-economic environment differs in particular on the level of the study regions. Due to a lack of production alternatives, agricultural production in grassland areas is very unstable – especially if site conditions are unfavourable and economic conditions are disadvantageous. As a result, largescale abandonment of agriculture is likely in lowyield grassland areas and consequences for landscape appearance might be dramatic. In highyield grassland areas, agriculture is much more stable. However, under very disadvantageous conditions the extent of farms giving-up production is as high as in marginal grassland regions. Nevertheless one cannot expect large-scale set aside, because remaining farmers use the possibility of growth and lease a considerable quantity of land In contrast to this, farm structure in the arable regions is stable due to a high potential of production alternatives. However, landscape appearance may also change dramatically in this region due to the increasing importance of maize.scenario analyses, structural change, landscape visualisation, Land Economics/Use,