Forschungskonzept zum ökologischen Landbau der Bundesforschungsanstalt für Landwirtschaft (FAL)

Am 28. Mai 2002 wurde das Forschungskonzept zum ökologischen Landbau der Bundesforschungsanstalt für Landwirtschaft (FAL) vom Kollegium und am 10. Juni vom Kuratorium der FAL beschlossen. Sie ergänzt das Forschungskonzept des Instituts für ökologischen Landbau (Ökologie & Landbau 3/2002) in Trenthorst und macht das Thema zu einer Aufgabe der gesamten Anstalt. Die 11 Institute der FAL decken die Gebiete und Forschungsdisziplinen ab, die für eine fundierte wissenschaftliche Bearbeitung dieser Fragen im ökologischen Landbau erforderlich sind. Die Forschung für den ökologischen Landbau geschieht im interdisziplinären Verbund

Forschung für den Ökolandbau in der FAL

In den letzten Jahren hat sich in der FAL eine beträchtliche Kompetenz zu Fragen des Ökolandbaus entwickelt. Viele Aktivitäten sind durch Drittmittel initiiert und finanziert, so dass eine weitere Stabilisierung erforderlich ist. In den Beiträgen und auch den Diskussionen des Kolloquiums zeigte sich teilweise noch zu geringe Vernetzung der Aktivitäten zwischen den Instituten, die weiter zu verbessern ist. Die Zusammenarbeit zwischen dem Institut für ökologischen Landbau (OEL) und den anderen Instituten der FAL hat sich erfreulich entwickelt, kann aber noch weiter vertieft werden. Das Institut OEL hat einen Versuchsbetrieb und ein breites Netzwerke im Ökolandbau aufgebaut. In Trenthorst gibt es einen anerkannt ökologisch geführte Versuchsbetrieb mit umfangreichen Flächenausstattung und Tierbeständen. Netzwerke und der Versuchsbetrieb sind grundsätzlich für andere Institute verfügbar

Product Configuration Systems: State of the Art, Conceptualization and Extensions

Product configurators are considered to be among the most successful applications of artificial intelligence technology. In this paper, we determine different conceptualizations of configurators and condense them in a comprehensive morphological box, which should support configurator designers as well as decision makers in selecting the right system. The analysis of the criteria according to which configurators that are designed thus far reveals a neglect of the front-end perspective. Therefore, it is relevant to extend configurators with a front-end component assisting customers during product configuration through advisory. We develop a framework describing the main requirements on an advisory system and propose the technical infrastructure for its implementation. Finally, the advisory system and the configurator are integrated into a comprehensive interaction system.product configurators; advisory system; product personalization

Dynamic Multi-Agent Based Variety Formation and Steering in Mass Customization

Large product variety in mass customization involves a high internal complexity level inside a company’s operations, as well as a high external complexity level from a customer’s perspective. To cope with both complexity problems, an information system based on agent technology is able to be identified as a suitable solution approach. The mass customized products are assumed to be based on a modular architecture and each module variant is associated with an autonomous rational agent. Agents have to compete with each other in order to join coalitions representing salable product variants which suit real customers’ requirements. The negotiation process is based on a market mechanism supported by the target costing concept and a Dutch auction. Furthermore, in order to integrate the multi-agent system in the existing information system landscape of the mass customizer, a technical architecture is proposed and a scenario depicting the main communication steps is specified.Product Configuration, Mass Customization, Variety Formation and Steering, Multi Agent System

Comparison of Canopy Openness in Different Cocoa (Theobroma cacao) Production Systems in Alto Beni, Bolivia

Cocoa (Theobroma cacao L.) grows naturally as an understory tree in tropical forests and produces well under shaded and non-shaded conditions. It is cultivated by small scale farmers in South America under various conditions, ranging from monocultures to different kinds of agroforestry systems. While in monocultures it is exposed to direct sunlight, one or various tree species shade the cocoa in agroforestry systems. Also organic cocoa cultivation is becoming more and more popular due to premium prices and increasing ecological consciousness. In Alto Beni, Bolivia, the Research Institute of Organic Agriculture (FiBL) and local partners have established a long-term field trial to compare cocoa production systems. The bi-factorial randomised block design includes management and biodiversity factors combined to the following five cocoa treatments: monoculture and agroforestry systems both under organic and conventional management, and successional agroforestry system (high plant species diversity) under organic management and for further comparison fallow plots of same age as the cocoa plots. Research is done in all fields of agronomic, economic and environmental interest. This study focuses on the comparison of the canopy openness of the different cocoa production systems and fallow plots. Knowledge about the canopy openness enables the estimation of light entering the production system, especially on the cocoa layer (photosynthesis relevant) and also on the soil as canopy openness influences the microclimate in the plantation. Another aspect of the canopy is the impact on the throughfall within the plot. Over the time, variations in the canopy structure indicate the production of biomass, of nutrient enrichment by throughfall (rain-wash and nutrient leaf leaching in the canopy) and may indicate pruning necessities when the plant cover above the cocoa exceeds critical values. To estimate the canopy openness, in the years 2012 and 2013 hemispherical photography was taken with fisheye lenses in the different cocoa production systems and in the fallow plots. The photos were analysed with the programme Gap Light Analyser. First results of canopy openness between the cocoa systems will be shown and discussed for leave area index and potential microclimate differences

Benthic Foraminifera biomass production in the western Baltic

The biomass (weight of protoplasm) and production of the major species of benthic Foraminifera was calculated for the "Hausgarten" area of Sonderforschungsbereich 95. Data from 440 samples collected between 1971 and 1975 were used for these calculations. Biomass production of Foraminifera is 10-90 mg wet weight/m2/y in the turbulent zone and up to 5411 mg/m2/y in the basins. Epiphytic species produce 13-26 mg wet weight/m2/y. These values are higher than those recorded in the literature with the exception of the subarctic. The foraminiferal proportion of total meiobenthos biomass ranges between 6% in the turbulent zone and 63% in the basin

Modelling hydrological impacts of agricultural expansion in two macro-catchments in Southern Amazonia, Brazil

This study presents the setup, calibration, validation and scenario application of the soil and water assessment tool for two contrasting macro-catchments along the Amazon agricultural frontier in the federal states of Pará and Mato Grosso, Brazil. Calibration and validation of the model are realised for the periods of the most intensive deforestation and agricultural expansion. In order to give consideration to the rapid, however gradual nature of land use change, the model implements an annual land use update combined with a land use dependent soil parameterization of the upper most soil layer. The comparison of these results with the results of a setup with a steady land use distribution shows distinct improvements of the prediction quality. Discharge prediction improves through the application of gradual land use change in the model by 12 % for a 1.8 % deforestation rate per year and 1.2 % for a deforestation rate of 0.7 % per year. Consequently, the validated models are applied to four land use scenarios for the period 2026–2035. Scenario simulation results show effects on the water balance proportional to land use change. Further, the changes in the water balance follow clear seasonal patterns with highest hydrological effects due to land use change during the rainy season in both catchments. Overall, with continuous deforestation, peak discharge increases. Further, the conversion of native vegetation to pasture has the highest impact on the water balance. For example, monthly discharge in the rainy season increases by up to 24 % for a 13 % conversion of Cerrado savannah into pasture

Process-based modelling of the impacts of land use change on the water balance in the Cerrado biome (Rio das Mortes, Brazil)

Since the 1980s, the state of Mato Grosso, Brazil, exhibits high rates of Cerrado conversion in favour of soybean expansion and cattle ranching. This conversion process becomes obvious in the upper Rio das Mortes macro-catchment. The objective of this study was to assess the influence of future land use changes on the discharge dynamics of the Rio das Mortes River. A single catchment approach was applied with the physically-based water balance simulation model WaSiM 8.5.0 (Schulla and jaSper 2007) to simulate land use scenarios. In Scenario 1, only small pasture sites (< 1 km²) were converted into the respective land use type surrounding them (i.e. cropland or Cerrado vegetation), whereas in Scenario 2 all pasture sites were converted into cropland and all Cerrado patches were then transformed into pastures. The WaSiM model was calibrated and validated based on discharge data measured at two gauging stations, achieving Nash-Sutcliffe coeffcients of 0.81 calibration) and 0.68 (validation). Main problems in modelling arise because of scarce spatial distributed data on subsurface parameter and vegetation parameter (Cerrado biome). Therefore, the use of the numerical groundwater model and manifold calibration runs were essential in this modelling approach to allow the simulation of the high levels of baseflow during the dry season and the transition from the dry to the wet season. The immediate rise of the baseflow in response to the increasing precipitation at beginning of the rainy season is a result of high soil hydraulic conductivity and groundwater recharge. These soil characteristics apparently persist on newly-created pasture and cropland sites, which still exhibit high ksat values after deforestation. Simulated evapotranspiration is comparable to literature values (Eddy flux measurements, MODIS-EVI calculation) and recently done paired micro-catchment studies in this catchment. The scenario analysis indicates that there are only small differences in runoff volume, which is directly related to the precipitation changes. In the scenario 2, groundwater recharge and base flow increase, whereas surface runoff does not. Therefore, the ongoing land use intensification with pasture conversion to cropland, remaining high infiltration and slight increase of evapotranspiration may not change runoff volume and discharge characteristics

Diatom and silicoflagellate fluxes at the Walvis Ridge: An environment influenced by coastal upwelling in the Benguela system

Seasonal fluctuations in the total particle, biogenic opal, diatom and silicoflagellate fluxes were observed in sediment traps deployed at 599 m and 1648 m in the Walvis Ridge area, within the Benguela upwelling system, from March 1989 to March 1990 (station WR 2: 20°02.8′S, 09°09.3′E). Fluxes were directly related to wind stress variations (wind maxima preceding flux maxima by several weeks), and inversely related to SST changes (derived from measured concentrations of C37 alkenones; range: 14.6°–23.6°C). The biogenic particle composition at different depths reflected the complicated hydrology of the area with a combination of tropical, temperate and subantarctic water masses. Biogenic opal content varied from about 2 to 12% of the total mass flux in the upper trap and from about 4 to 17% in the lower trap. Diatoms were the main contributor to the opal fraction (mean daily flux of ca. 5.5 * 106 valves m−2 day−1), followed by silicoflagellates (ca. 2.6 * 105 skeletons m−2 day−1). Two seasonal maxima, in May and June (austral autumn) and from October to November (austral spring), were observed; silicoflagellates yielded also a third moderate maximum in August/September (austral winter). At 1648 m fluxes peaked from May to July (data were available for the period 18 Mar to 27 Aug 1989 only). Few diatoms were abundant; 19 taxa accounted for 50% of all the diatoms identified, and about 32 for the 75% level. Specific diversity of diatoms at 599 m was highest during times of lowest fluxes, in the austral winter, late spring and summer. The diatom taxa occurring at 599 m and at 1648 m were the same, with some flux enrichment with depth due to advection of particles into the lower trap by resuspension and downslope movement. The relatively high concentrations of the Antarctic-Subantarctic species Fragilariopsis kerguelensis in the upper trap solely, was probably linked to selective entrainment and transport within a ring of southerly origin (south of the Subantarctic/Subtropical Convergence Zone). The enrichment of moderately resistant and robust taxa in the sediments in conjunction with the rarity or absence of delicate taxa points to preferential concentration in the sediments of some taxa and dissolution of others. The occurrence of phytoliths in the traps and in the sediment sample can be linked to the “berg” winds, which are typical for the entire Benguela region during fall and winter

Product Configuration Systems: State of the Art, Conceptualization and Extensions

Product configurators are considered to be among the most successful applications of artificial intelligence technology. In this paper, we determine different conceptualizations of configurators and condense them in a comprehensive morphological box, which should support configurator designers as well as decision makers in selecting the right system. The analysis of the criteria according to which configurators that are designed thus far reveals a neglect of the front-end perspective. Therefore, it is relevant to extend configurators with a front-end component assisting customers during product configuration through advisory. We develop a framework describing the main requirements on an advisory system and propose the technical infrastructure for its implementation. Finally, the advisory system and the configurator are integrated into a comprehensive interaction system