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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.

2018

To document

Abstract

Due to the increasing relevance of analyzing water consumption along product life cycles, the water accounting and vulnerability evaluation model (WAVE) has been updated and methodologically enhanced. Recent data from the atmospheric moisture tracking model WAM2-layers is used to update the basin internal evaporation recycling (BIER) ratio, which denotes atmospheric moisture recycling within drainage basins. Potential local impacts resulting from water consumption are quantified by means of the water deprivation index (WDI). Based on the hydrological model WaterGAP3, WDI is updated and methodologically refined to express a basin’s vulnerability to freshwater deprivation resulting from the relative scarcity and absolute shortage of water. Compared to the predecessor version, BIER and WDI are provided on an increased spatial and temporal (monthly) resolution. Differences compared to annual averages are relevant in semiarid and arid basins characterized by a high seasonal variation of water consumption and availability. In order to support applicability in water footprinting and life cycle assessment, BIER and WDI are combined to an integrated WAVE+ factor, which is provided on different temporal and spatial resolutions. The applicability of the WAVE+ method is proven in a case study on sugar cane, and results are compared to those obtained by other impact assessment methods.

Abstract

In recent years, slatted floors made of materials like fiber composite and plastic have been introduced in animal housing systems. These modern floor types are claimed to have low heat conductivity and hence be “better” for the sheep than expanded metal, but the actual preference in sheep has not yet been tested. The aim of this study was to investigate the preference of ewes for different floor materials at low ambient temperatures. The experiment was performed in a non-insulated building and the indoor air temperature varied from -11.8 to + 3 °C. Each experimental pen measured 3.0 x 2.0 m (total 6.0 m2) and were divided into two equal sections (A and B). A total of 30 non-pregnant ewes were sheared and allocated to one of ten stable groups with three animals per group. Five different floor types – expanded metal, slatted floor made of fiber composite, slatted floor made of plastic, solid floor made of wood and solid floor consisting of a rubber mat, were installed in section A and B in the experimental pens. Groups were habituated to all floor material combinations and systematically rotated through the ten pens. Behaviors were scored from 20 hour video recordings using instantaneous sampling at 10 minute intervals. In addition, heat conductivity properties of the five different floor materials were tested. On days with low temperatures, the ewes were standing or walking more, resting less, eating or drinking more and resting more in physical contact than on days with higher temperatures. When given the choice, ewes showed clear preferences for standing/walking and resting on solid floor materials than on slatted floors. This is consistent with earlier preference tests on sheared sheep. Ewes did not seem to show a clear preference for one slatted floor material over another for resting. The proportion of time spent standing/walking in the pen was steadily reduced as air temperature in the barn increased. The present experiment suggests that none of the floor combinations had thermal properties that adversely affect resting and other general behaviors of the animals. The heat conductivity properties were similar among the slatted floors. In conclusion, the claimed favorable thermal properties of plastic slatted floors and fiber composite were not confirmed. There must be other properties of the floor than heat conductivity that influences the preference in ewes.

To document

Abstract

In recent years, slatted floors made of materials like fiber composite and plastic have been introduced in animal housing systems. These modern floor types are claimed to have low heat conductivity and hence be “better” for the sheep than expanded metal, but the actual preference in sheep has not yet been tested. The aim of this study was to investigate the preference of ewes for different floor materials at low ambient temperatures. The experiment was performed in a non-insulated building and the indoor air temperature varied from -11.8 to + 3 °C. Each experimental pen measured 3.0 x 2.0 m (total 6.0 m2) and were divided into two equal sections (A and B). A total of 30 non-pregnant ewes were sheared and allocated to one of ten stable groups with three animals per group. Five different floor types – expanded metal, slatted floor made of fiber composite, slatted floor made of plastic, solid floor made of wood and solid floor consisting of a rubber mat, were installed in section A and B in the experimental pens. Groups were habituated to all floor material combinations and systematically rotated through the ten pens. Behaviors were scored from 20 hour video recordings using instantaneous sampling at 10 minute intervals. In addition, heat conductivity properties of the five different floor materials were tested. On days with low temperatures, the ewes were standing or walking more, resting less, eating or drinking more and resting more in physical contact than on days with higher temperatures. When given the choice, ewes showed clear preferences for standing/walking and resting on solid floor materials than on slatted floors. This is consistent with earlier preference tests on sheared sheep. Ewes did not seem to show a clear preference for one slatted floor material over another for resting. The proportion of time spent standing/walking in the pen was steadily reduced as air temperature in the barn increased. The present experiment suggests that none of the floor combinations had thermal properties that adversely affect resting and other general behaviors of the animals. The heat conductivity properties were similar among the slatted floors. In conclusion, the claimed favorable thermal properties of plastic slatted floors and fiber composite were not confirmed. There must be other properties of the floor than heat conductivity that influences the preference in ewes.

To document

Abstract

Winter manure application elevates nutrient losses and impairment of water quality as compared to manure applications in other seasons. In conjunction with reviewing global distribution of animal densities, we reviewed worldwide mandatory regulations and voluntary guidelines on efforts to reduce off-site nutrient losses associated with winter manure applications. Most of the developed countries implement regulations or guidelines to restrict winter manure application, which range from a regulative ban to guidelines based upon weather and field management conditions. In contrast, developing countries lack such official directives, despite an increasing animal production industry and concern over water quality. An analysis of five case studies reveals that directives are derived from a common rationale to reduce off-site manure nutrient losses, but they are also affected by local socioeconomic and biophysical considerations. Successful programs combine site-specific management strategies along with expansion of manure storage to offer farmers greater flexibility in winter manure management.