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Müncheberg, Germany
Müncheberg, Germany
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Rees R.M.,Scotland’s Rural College | Augustin J.,ZALF | Alberti G.,University of Udine | Ball B.C.,Scotland’s Rural College | And 30 more authors.
Biogeosciences | Year: 2013

Nitrous oxide emissions from a network of agricultural experiments in Europe were used to explore the relative importance of site and management controls of emissions. At each site, a selection of management interventions were compared within replicated experimental designs in plot-based experiments. Arable experiments were conducted at Beano in Italy, El Encin in Spain, Foulum in Denmark, Logärden in Sweden, Maulde in Belgium, Paulinenaue in Germany, and Tulloch in the UK. Grassland experiments were conducted at Crichton, Nafferton and Peaknaze in the UK, Gödöllö in Hungary, Rzecin in Poland, Zarnekow in Germany and Theix in France. Nitrous oxide emissions were measured at each site over a period of at least two years using static chambers. Emissions varied widely between sites and as a result of manipulation treatments. Average site emissions (throughout the study period) varied between 0.04 and 21.21 kgN2O-N ha-1 yr-1, with the largest fluxes and variability associated with the grassland sites. Total nitrogen addition was found to be the single most important determinant of emissions, accounting for 15% of the variance (using linear regression) in the data from the arable sites (p <0.0001), and 77% in the grassland sites. The annual emissions from arable sites were significantly greater than those that would be predicted by IPCC default emission factors. Variability of N 2O emissions within sites that occurred as a result of manipulation treatments was greater than that resulting from site-to-site and year-to-year variation, highlighting the importance of management interventions in contributing to greenhouse gas mitigation. © Author(s) 2013.


Knierim A.,University of Hohenheim | Knierim A.,Leibniz Center for Agricultural Landscape Research | Boenning K.,ZALF | Caggiano M.,French National Institute for Agricultural Research | And 5 more authors.
Outlook on Agriculture | Year: 2015

Recently, Agricultural Knowledge and Innovation Systems (AKISs) have gained considerable attention in scientific and political forums in the European Union (EU). AKIS is considered a key concept in identifying, analysing and assessing the various actors in the agricultural sector as well as their communication and interaction for innovation processes. Using qualitative expert interviews and organizational mapping, the features of national AKISs were investigated in selected EU member states (Belgium, France, Ireland, Germany, Portugal and the UK). The authors present the different national AKISs and compare them qualitatively with regard to their institutional settings, their overall policy frameworks and their coordinating structures. Conclusions are drawn with regard to AKIS appraisal in general and the usefulness of the AKIS concept, particularly for the understanding and evaluation of policy-induced innovation in agriculture.


Leuschner C.,University of Gottingen | Wulf M.,ZALF | Wulf M.,University of Potsdam | Bauchler P.,Tauernallee 13 | Hertel D.,University of Gottingen
Forest Ecology and Management | Year: 2013

In the diluvial lowlands of northern Germany, the Netherlands and northern Poland, an estimated ~5 Mio ha of Scots pine plantations (Pinus sylvestris) has been established on sandy soil in the last 250years replacing the former temperate broad-leaved forests after extended periods of cultivation in the Middle Ages. We examined the effect of variable stand continuity of pine plantations (recent vs. ancient: 51-128 vs. >230years) on the soil organic carbon (SOC) store and soil nutrient capital in comparison to ancient beech forests (>230years of continuity) which represent the potential natural forest vegetation. Recent and ancient pine stands had c. 75% larger organic layer C stores than ancient beech forests, while the total C stock in the soil (organic layer and mineral soil to 100cm) was ~25% larger in the beech forests due to higher C concentrations in 0-50cm depth of the mineral soil. The soil stores of Ntot were ~50% and the exchangeable Ca, K and Mg pools about three times larger under beech than under the pine stands. Resin-exchangeable P was enriched in the soils under ancient pine stands probably due to manuring in the past. After clear-cut and long cultivation, it may take>230years of forest presence to restore the greatly reduced mineral soil C and N pools. The C and N sequestration potential of the soils appeared to be particularly small under pine indicating a pronounced tree species (pine vs. beech) effect on soil C and N dynamics. We conclude that, in the face of rising greenhouse gas emissions, the limited soil C and nutrient storage potential of Scots pine plantations on sandy soils needs consideration when selecting suitable tree species for future forestry. © 2013 Elsevier B.V.


Prager K.,Humboldt University of Berlin | Schuler J.,ZALF | Helming K.,ZALF | Zander P.,ZALF | And 2 more authors.
Land Degradation and Development | Year: 2011

There is a lack of knowledge about the effectiveness and efficiency of soil conservation policies in agriculture and there is a little understanding of how policy measures should be designed to encourage farmers to adopt soil conservation practices. This paper analyses institutional settings surrounding agricultural soil management in ten European countries based on the Institutions of Sustainability (IoS) framework. This framework considers the interdependencies between ecological and social systems, taking into account environmental conditions, farming practices impacting on soil conservation, different types of actors, policies, institutions and governance structures. The purpose of this paper is to describe the analytical framework and the methodology that all case studies are based on, present and discuss compared findings, outline implications for successful soil conservation policy and draw conclusions on the methodological approach. The case studies focused on the main soil degradation types occurring across Europe which are addressed by a broad range of mandatory and incentive policies. The findings highlight the following issues: (i) the need to design policies that target the locally most common soil threats and processes in the light of agricultural management; (ii) the need to take farming management constraints into consideration, (iii) the need for good communication and cooperation both between agricultural and environmental authorities as well as between governmental and non-governmental stakeholders; (iv) the necessary mix of mandatory and incentive instruments and (v) the need for data and monitoring systems allowing the evaluation of the effectiveness of policies and soil conservation practices. © 2010 John Wiley & Sons, Ltd.


Chojnicki B.H.,University of Life Sciences in Poznań | Michalak M.,University of Life Sciences in Poznań | Acosta M.,University of Life Sciences in Poznań | Juszczak R.,University of Life Sciences in Poznań | And 3 more authors.
Polish Journal of Environmental Studies | Year: 2010

The assessment of net ecosystem exchange (NEE) and respiration of ecosystem (Reco) of terrestrial ecosystems is necessary to improve our knowledge about the carbon cycle. The aims of this paper were to present reliable measurements of CO2 fluxes of a temperate bog ecosystem located in Poland using a closed dynamic chamber system and to obtain a daily dynamic course of CO 2 fluxes over the 2007 vegetation season. Measurements of CO 2 fluxes were carried out at Rzecin peatland ecosystem located in northwestern Poland using the set of two chambers (dark and transparent). Reco during the experiment period ranged from 2.65 to 14.76 μmolCO 2·m-2·s-1. The daily run of NEE was inversed to PPFD and the values of NEE varied from 0.06 to -11.82 μmolCO2·m-2·s-1. We found differences between NEE and Reco in the wetland ecosystem with respect to term of measurements. The PPFD, air and soil temperatures explain most temporal variability of CO2 fluxes at Rzecin. But vegetation structure, its phenology and water-level depth seem also to play important roles. The chamber technique is a useful tool for determining carbon dioxide exchange between wetland surface and the atmosphere.


Leuschner C.,University of Gottingen | Wulf M.,ZALF | Wulf M.,University of Potsdam | Bauchler P.,Tauernallee 13 | Hertel D.,University of Gottingen
Ecosystems | Year: 2014

Forest (or tree) age has been identified as an important determinant of the carbon (C) storage potential of forest soils. A large part of Central Europe's current forested area was affected by land use change with long periods of cultivation in past centuries suggesting that the organic C stocks in the soil (SOC) under recent forest may partly be legacies of the past and that stand age effects have to be distinguished from forest continuity effects (that is, the time since re-afforestation). We examined the influence of mean tree age and forest continuity on the SOC pool and the stores of total N and available P, Ca, Mg, and K in the soil (mineral soil and organic layer) across a sample of 14 beech (Fagus sylvatica) forests on sandy soil with variable tree age (23-189 years) and forest continuity (50-year-old afforestation to ancient ('permanent') forest, that is, >230 years of proven continuity). Ancient beech forests (>230 years of continuity) stored on average 47 and 44% more organic C and total N in the soil than recent beech afforestation (50-128 years of continuity). Contrary to expectation, we found large and significant C and N pool differences between the forest categories in the mineral soil but not in the organic layer indicating that decade- or century-long cultivation has reduced the subsoil C and nutrient stores while the organic layer element pools have approached a new equilibrium after only 50-128 years. PCA and correlation analyses suggest that forest continuity cannot be ignored when trying to understand the variation in soil C stocks between different stands. Forest clearing, subsequent cultivation, and eventual re-afforestation with beech resulted in similar relative stock reductions of C and N and, thus, no change in soil C/N ratio. We conclude that the continuity of forest cover, which may or may not be related to tree age, is a key determinant of the soil C and nutrient stores of beech forests in the old cultural landscape of Central Europe. © 2013 Springer Science+Business Media New York.


Roosenschoon O.,Wageningen University | Reis S.,UK Center for Ecology and Hydrology | Turnpenny J.,University of East Anglia | Adele C.,University of East Anglia | And 6 more authors.
iEMSs 2012 - Managing Resources of a Limited Planet: Proceedings of the 6th Biennial Meeting of the International Environmental Modelling and Software Society | Year: 2012

Many impact assessment (IA) models focus on effects of policy measures on environment and ecology. There are various examples of sophisticated IA models and models that are actually used in the policy making process. However, in many cases, there is still is a gap between the actual and potential use of these models in IA. Why is this so and what can be improved about this? The LIAISE project (www.liaise-noe.eu) is initiated to investigate just this. The hypothesis is that in many cases model use is not successful, because there is a gap between the two communities of IA researchers and IA practitioners. This gap is created by the fact that IA researchers are interested in new approaches and innovations, whereas IA practitioners need tools which are easy to use and give transparent, understandable results. In this paper we discuss the first results of interviews with policymakers, on national as European level on how tools are being used in daily practice and on what research questions we need to get answered. We will describe the first version of the RM-IAT, the reference model for impact assessment tools, which proposes a standardized way to describe models and tools. We will introduce the LIAISE Front Office and Back Office toolbox, where tools are presented in such a way to the users of the toolbox, that the users are able to make a better choice of which model to use, and by doing so, are able to use models with more success. Some tools will actually be made available in the Back Office. We can conclude that tool use in the European countries depends on the context in which they are used: it depends on the tool, it depends on the user, it depends for what purpose the tool is used.


Wieland R.,ZALF | Mirschel W.,ZALF | Deumlich D.,ZALF
iEMSs 2012 - Managing Resources of a Limited Planet: Proceedings of the 6th Biennial Meeting of the International Environmental Modelling and Software Society | Year: 2012

The paper introduces different approaches to parallelization based on Open- MPI and OpenMP applied to the Universal Soil Loss Equation (USLE). The USLE was used as a proxy for similar models from the "impact assessment toolbox". The simulation of impact assessment takes into account climate change and changes in management. Even such a simple model as the USLE can lead to a time-consuming simulation when applied to a large region and when including stochastic data. The paper discusses the pros and cons of the implemented parallelization techniques. The key technology is to divide the simulation into two parts: a binary part implemented in C++ and an interpreter part which controls the parallel simulation written in Python. Python and its modules were also used to pre- And post-process the simulation.

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