Broder Breckling

Will climate change increase irrigation requirements in agriculture of Central Europe? A simulation study for Northern Germany

BackgroundBy example of a region in Northern Germany (County of Uelzen), this study investigates whether climate change is likely to require adaption of agricultural practices such as irrigation in Central Europe. Due to sandy soils with low water retention capacity and occasional insufficient rainfall, irrigation is a basic condition for agricultural production in the county of Uelzen. Thus, in the framework of the comprehensive research cluster Nachhaltiges Landmanagement im Norddeutschen Tiefland (NaLaMa-nT), we investigated whether irrigation might need to be adapted to changing climatic conditions. To this end, results from regionalised climate change modelling were coupled with soil- and crop-specific evapotranspiration models to calculate potential amounts of irrigation to prevent crop failures. Three different runs of the climate change scenario RCP 8.5 were used for the time period until 2070.ResultsThe results show that the extent of probable necessary irrigation will likely increase in the future. For the scenario run with the highest temperature rise, the results suggest that the amount of ground water presently allowed to be extracted for irrigation might not be sufficient in the future to retain common agricultural pattern.ConclusionsThe investigation at hand exemplifies data requirements and methods to estimate irrigation needs under climate change conditions. Restriction of ground water withdrawal by German environmental regulation may require an adaptation of crop selection and alterations in agricultural practice also in regions with comparable conditions.

Information system for monitoring environmental impacts of genetically modified organisms

Background, aim and scopeEuropean legislation stipulates that genetically modified organisms (GMO) have to be monitored to identify potential adverse environmental effects. A wealth of different types of monitoring data from various sources including existing environmental monitoring programmes is expected to accumulate. This requires an information system to efficiently structure, process and evaluate the monitoring data.MethodsA structure for an Information System for Monitoring GMO (ISMO) was developed by a multidisciplinary research team. It is based on the requirement to organise all relevant information in a logical, readily accessible and functional manner.ResultsFor the ISMO, we present a combination of three interrelated components: Firstly, an ISMO should comprise a knowledge database structured according to information related to the different scale levels of biological organisation relevant to GMO monitoring and scientific hypotheses on cause–effects which should be validated by monitoring data. Secondly, a monitoring database should be part of an ISMO containing GMO-specific monitoring data and meta-data. This monitoring database should be linked with monitoring data from other monitoring programmes which are relevant for GMO-related questions. Thirdly, an ISMO should encompass a database covering administrative and procedural data. Neither national nor international approaches to an ISMO exist yet.ConclusionsAn ISMO as designed in this paper could support competent authorities in both the GMO notification process and in post-market monitoring. This includes evaluating the environmental risks of experimentally releasing GMO and placing them on the market, assessing monitoring plans and evaluating monitoring results. The ISMO should be implemented on both the national and international level, preferably combining different administrative scales. Harmonisation approaches towards GMO monitoring data are at an initial stage, but they are a precondition to coordinated GMO monitoring and to successfully implementing an ISMO. It is recommended to set up a legal basis and to agree on common strategies for the data coordination and harmonisation.

Competition and coexistence: the contribution of modelling to the formation of ecological concepts

Abstract Competition is a basic concept in ecology and plays a fundamental role in the consistency of established ecological theory. This paper refers to the roundtable discussion held at the 1992 ISEM Conference in Kiel (Germany) and reflects the current state of discussion about this concept. The authors conclude that (1) competition originates as an abstract term from social and economic experience, (2) the competitive exclusion principle and its theoretical implications are founded on assumptions of spatial homogeneity, and that (3) this concept therefore lacks the consistency required to achieve a practically valid and generally applicable theory for the interpretation of ecological interactions in the field. In contrast to the central position of competition in theory, empirical investigations support the view that it only plays a minor role in community dynamics and evolution. However, to abandon competition as the fundamental concept in population ecology substantially reduces the achievable degree of generality in ecological theory. As a result, theory will become more domain-specific, whereas unifying principles may be established on meta-levels of theory.

Modelling regional variability of irrigation requirements due to climate change in Northern Germany

The question whether global climate change invalidates the efficiency of established land use practice cannot be answered without systemic considerations on a region specific basis. In this context plant water availability and irrigation requirements, respectively, were investigated in Northern Germany. The regions under investigation--Diepholz, Uelzen, Fläming and Oder-Spree--represent a climatic gradient with increasing continentality from West to East. Besides regional climatic variation and climate change, soil conditions and crop management differ on the regional scale. In the model regions, temporal seasonal droughts influence crop success already today, but on different levels of intensity depending mainly on climate conditions. By linking soil water holding capacities, crop management data and calculations of evapotranspiration and precipitation from the climate change scenario RCP 8.5 irrigation requirements for maintaining crop productivity were estimated for the years 1991 to 2070. Results suggest that water requirement for crop irrigation is likely to increase with considerable regional variation. For some of the regions, irrigation requirements might increase to such an extent that the established regional agricultural practice might be hard to retain. Where water availability is limited, agricultural practice, like management and cultivated crop spectrum, has to be changed to deal with the new challenges.

The ecological effect of phenotypic plasticity — Analyzing complex interaction networks (COIN) with agent-based models

Abstract Analyzing complex dynamics of ecological systems is complicated by two important facts: First, phenotypic plasticity allows individual organisms to adapt their reaction norms in terms of morphology, anatomy, physiology and behavior to changing local environmental conditions and trophic relationships. Secondly, individual reactions and ecological dynamics are often determined by indirect interactions through reaction chains and networks involving feedback processes. We present an agent-based modeling framework which allows to represent and analyze ecological systems that include phenotypic changes in individual performances and indirect interactions within heterogeneous and temporal changing environments. We denote this structure of interacting components as COmplex Interaction Network (COIN). Three examples illustrate the potential of the system to analyze complex ecological processes that incorporate changing phenotypes on the individual level: • A model on fish population dynamics of roach ( Rutilus rutilus ) leads to a differentiation in fish length resulting in a conspicuous distribution that influences reproduction capability and thus indirectly the fitness. • Modeling the reproduction phase of the passerine bird Erithacus rubecula (European Robin) illustrates variation in the behavior of higher organisms in dependence of environmental factors. Changes in reproduction success and in the proportion of different activities are the results. • The morphological reaction of plants to changes in fundamental environmental parameters is illustrated by the black alder ( Alnus glutinosa ) model. Specification of physiological processes and the interaction structure on the level of modules allow to represent the reaction to changes in irradiance and temperature accurately. Applying the COIN-approach, individual plasticity emerges as a structural and functional implication in a self-organized manner. The examples illustrate the potential to integrate existing approaches to represent detailed and complex traits for higher order organisms and to combine ecological and evolutionary aspects.

A modeling assessment of geneflow in smallholder agriculture in West Africa

PurposeSmall-scale agriculture is an important issue for food security in Africa. In the context of Genetically Modified Organisms, approaches to quantify geneflow in small-scale systems are widely unexplored. We aimed at bridging this gap by contributing to the scientific discussion on the uncertainties of the cultivation of genetically modified (GM) crops in the region. The safety issue is: Would it be possible to withdraw a variety in case that unexpected and undesirable effects occur? e.g. the resistance of pests which make the variety no more useful.MethodsWe used a GIS approach to determine the location of maize cultivation sites, field geometries and applied a model for the calculation of geneflow scenarios.ResultsThe data revealed that the given cropping density provides optimal conditions for transgene spread, potentially limiting the possibility for coexistence between GM and non-GM fields. On average, we found about 60 fields within a nearest distance of 100 m, and cropping density of 56 fields per square kilometer. The resulting cross-pollination rate from the single GM field into the neighbouring conventional fields was estimated to be about 0.12%.ConclusionsGM varieties if introduced could remain in cultivation even if their admission has expired or has been retracted. This would be undesirable and could cause long-term, undesirable stacked combination of transgenes which cannot be tested with respect to eventual combinatory effects. These developments pose major challenges for fielder livelihoods, and conservation of maize genetic resources with potentially negative consequences for the African food export sector.

Information System for the Monitoring of Genetically Modified Organisms (GMO) – ISMO –

Abstract.Regarding the increasing number of GMO, a large amount of different types of data from various sources will be accumulated. Expected amount and quality of data emphasises the need for a respective information system to efficiently process and evaluate monitoring data. A concept for such an Information System for the MOnitoring of GMOs (ISMO) has been developed for the German Agency for Nature Conservation (BfN). The aim of the system is to support the competent authorities, especially the BfN, with their tasks in the notification process and the post market analysis of environmental effects.This paper will focus on the conceptual background as well as on components and structure of the information system to be developed.

Targets, Goals and Orientors

This volume attempts to combine ecological theory with environmental practice, thermodynamics with environmental planning, network theory with agricultural strategies, theoretical aspects such as self-organization and emergence with environmental economy, jurisdiction, philosophy and sociology.

Individual-Based Models

This chapter will describe the category of models that represent the behaviour and interaction of distinct individuals with specific properties. Models of this type can become very complex, but have the advantage that model structures operate on a low level of abstraction and represent ecological relations in a form similar to empirical assessment. Individual-based models facilitate studies of emergent properties, where characteristics of higher level entities like populations or communities can be generated on the basis of single actions of particular individuals. They allow to simultaneously investigate energetic and physiological aspects, behaviour, and relations to other organisms and heterogeneous environmental structures. As a technical background, object-oriented programming is frequently used for this model approach. This chapter introduces the conceptual background and describes two case studies, one that investigates spatial aspects of a predator–prey interaction, and a second one which depicts community interactions of Northern Scandinavian small mammals with oscillating population dynamics.

What Are the General Conditions Under Which Ecological Models Can be Applied

The purpose of this chapter is to discuss the conditions under which models can be applied. Modelling can help to solve specific problems, but not all questions in ecology require or benefit from the application of a model. It is therefore necessary to have an idea about the criteria under which the development of a model can provide useful information or help to solve questions in ecological analysis and which conceptual and technical approaches are the most appropriate ones. Technical knowledge about the particular modelling techniques is presented in the subsequent chapter of this book. Here, we intend to give an overview of the basic criteria of model application.