Beiträge von Hansueli Dierauer in der Schweizer Landtechnik 2012

Unkrautregulierung durch Abflammen. Schweizer Landtechnik, 10.02.2012, S. 62 Unkrautregulierung: Welche Hacke wählen? Schweizer Landtechnik, 12.01.2012, S. 2

Reducing cross-sucking of group housed calves by an environmental enriched building design

Group housing is a natural and economic way of raising calves. One major disadvan-tage of group housing calves is the occurrence of cross-sucking as an abnormal behaviour. The main objective of our study on organic calf housing was the reduction of cross-sucking related to milk feeding. A new feeding stall with automatic gates was attached to an automatic teat feeder. One gate opened to an enriched area immedi-ately when the calves had finished their milk meal. In this zone calves could use rub-ber teats or a hay net (treatment optimized). The design for the control group used a simple feeding stall without attached enriched zone. 168 female calves (German Holstein) from one origin (herd) were randomly assigned to 14 groups with 12 calves each. Thus, each treatment could be repeated seven times. Two groups were used for preliminary testing of housing and technique. Calves were fed whole milk, according to EU-organic-farming-guidelines. The behaviour of calves was observed directly for 20 minutes following milk intake. In addition, 24 hour video observation completed the behavioural monitoring. The videos were analyzed with the continuous sampling method; statistical analysis was done with the SAS statistical software package and non-parametric procedures. As one result, cross-sucking of calves decreased signifi-cantly in the optimized housing treatment compared to the control treatment: cross-sucking behaviour occurred for 12% of the calves of the optimized treatment vs. 60% cross-sucking calves in the control treatment. Regarding the intensity of cross-sucking, the control group showed 200 cross-sucking bouts per 100 calves and meal, in comparison with a frequency of 16 bouts of the optimized treatment. Our study supports the thesis, that design of housing and environment could be used to reduce cross-sucking of group housed calves. However, future research should be done to evaluate interactions between feeding techniques, environment and physiological processes related to cross-sucking behaviour of calves

Dry anaerobic digestion of organic residues on-farm - a feasibility study

Objectives The feasibility study shall answer the following questions: Are there economical and ecological advantages of on-farm dry digestion biogas plants? How the construction and operation parameters of a dry digestion biogas plant influence environment, profit, and sustainability of on-farm biogas production? The aim of the feasibility study is to provide facts and figures for decision makers in Finland to support the development of the economically and environmentally most promising biogas technology on-farm. The results may encourage on-farm biogas plant manufacturers to develop and market dry anaerobic digestion technology as a complementary technology. This technology may be a competitive alternative for farms using a dry manure chain or even for stockless farms. Results Up to now farm scale dry digestion technology does not offer competitive advantages in biogas production compared to slurry based technology as far as only energy production is concerned. However, the results give an over-view of existing technical solutions of farm-scale dry digestion plants. The results also show that the ideal technical solution is not invented yet. This may be a challenge for farmers and entrepreneurs interested in planning and developing future dry digestion biogas plants on-farm. Development of new dry digestion prototype plants requires appropriate compensation for environmental benefits like closed energy and nutrient circles to improve the economy of biogas production. The prototype in Järna meets the objectives of the project since beside energy a new compost product from the solid fraction was generated. On the other hand the two-phase process consumes much energy and the investment costs are high (>2000 € m-3 reactor volume). Dry digestion on-farm offers the following advantages: Good process stability and reliability, no problems like foam or sedimentation, cheap modules for batch reactors, less reactor capacity, reduced transport costs due to reduced mass transfer in respect of the produced biogas quantity per mass unit, compost of solid digestion residues suitable as fertiliser also outside the farm gate, use of on-farm available technology for filling and discharging the reactor, less process energy for heating because of reduced reactor size, no process energy for stirring, reduced odour emissions, reduced nutrient run off during storage and distribution of residues because there is no liquid mass transfer, suitable for farms using deep litter systems. These advantages are compensated by following constraints: Up to 50% of digestion residues are needed as inoculation material (cattle manure does not need inoculation) requiring more reactor capacity and mixing facilities. Retention time of dry digestion is up to three times longer compared to wet digestion requiring more reactor capacity and more process energy, filling and discharging batch reactors is time and energy consuming. We conclude that only farm specific conditions may be in favour for dry digestion technology. Generally, four factors decide about the economy of biogas production on-farm: Income from waste disposal services, compensation for reduction of greenhouse gas emission, compensation for energy production and - most important for sustainable agriculture - nutrient recycling benefits. Evaluation of the results We did not find any refereed scientific paper that includes a documentation of an on-farm dry digestion biogas plant. It seems that we tried first. We also could not find any results about the biogas potential of oat husks, so we may have found these results first. Farm scale production of anaerobically treated solid manure for composting is new. Dry fermentation biogas plants offer the possibility to design solid manure compost by variation of fermentation process parameters. From different scientific publication databases we found about 10 000 references concerning biogas research during the past 10 years. Less than ten are dealing with biogas reactors for non-liquid substrates on-farm. Recent research mainly concentrates on basic research, biogas process research for communal waste, large-scale biogas plants, and research on laboratory level. This mirrors the fact, that production of research papers is rather financed than product development on site. Our conclusion is that it seems worldwide to be very difficult or even impossible to find financial support for on site research, especially for on-farm prototype biogas reactors. We suppose the following reasons for this fact: biogas plant research requires proficiency in many different scientific disciplines, lack of co-operation between engineering and life sciences, high development costs to transfer basic research results into practical technical solutions, low interest of researchers because on site and on-farm research enjoys low appreciation in terms of scientific credits, portability of farm specific design and process solutions is difficult. Our conclusion is that on site and on-farm research has to be supported by funding agencies if integration of biogas and bio energy into the farm organism is considered as an important target within the agricultural policy framework. Future research on both dry fermentation technique and biogas yield of solid organic residues may close present knowledge gaps. Prototype research may offer competitive alternatives to wet fermentation for farms using a solid manure chain and/or energy crops for biogas production. To encourage farmers and entrepreneurs to foster the development of dry fermentation technology support in terms of education and advisory services is also necessary

Ein kleiner Laufstall im Ökomilchviehbetrieb

Um die Wettbewerbsfähigkeit der Betriebe mit Tierhaltung in Bayern zu verbessern, müssen kostengünstige, flexibel nutzbare und gleichzeitig tiergerechte Baulösungen entwickelt werden. Im Rahmen einer Untersuchung unterschiedlicher Bauweisen für Milchviehställe konnten zwischen einhäusigen, großvolumigen und mehrhäusigen Anlagen Kosteneinsparungen von 25 - 40% aufgezeigt werden. Eine weitere Reduzierung der Kosten bei letzteren durch mehr mögliche Eigenleistung ist dabei noch nicht berücksichtigt. Diese mehrhäusigen Anlagen werden in Form von Tragkonstruktionen aus Holz mit geringen Spannweiten weiterentwickelt und über die Arbeitsgemeinschaft für Landtechnik und landwirtschaftliches Bauwesen in Bayern e.V. (ALB) im Rahmen des Weihenstephaner Bauprogramms bauwilligen Landwirten angeboten. Darüber hinaus werden diese Baukonzepte auf bayerischen Pilotbetrieben umgesetzt. Hieraus ergeben sich neue Erkenntnisse zur Optimierung und baulich-technischen Weiterentwicklung kostengünstiger Bauweisen für landwirtschaftliche Nutzgebäude. Im Rahmen dieser Pilotprojekte werden belastbare Daten über den Investitionsbedarf sowie zum Stallklima und zur Funktionssicherheit der Anlagen erhoben. Am Projektbeispiel für einen kleinen Milchviehstall werden diese Schritte und erste Teilergebnisse dargestellt

Inter-row subsoiling increases marketable yield in potatoes

Inter-row subsoiling increased average yield of 40-65 mm potatoes by 14 pct during 2001-2003. But there were significant differences between the years. In 2001, the yield increased by 49 pct, whereas it was unaffected or decreased in 2002 and 2003. Better understanding of optimal subsoiling conditions is needed to exploit the benefit of inter-row subsoiling

Kosten der Belüftungsheuerzeugung in Boxen oder Ballen

The production of ventilated barn hay results in a high quality fodder for ruminants. Nevertheless, this production method is still a niche in Germany even it is found in organic farming. Reasons are the few publications about required investments of the needed technology for hay drying in the barn. This article provides investment and energy costs for different drying techniques: for box hay drying three different farm sizes were compared, for bale hay drying only one farm size is calculated. Bale hay drying demands more power and investment cost as box hay drying of loose hay. Bale drying is more complicated than barn drying in that the number of bale drying locations in a barn is a limiting factor to throughput, as is also the drying of densely packed bales. Barn drying is above all practical on farms where hay is the only forage on offer. Its particular advantage is the large amounts of crop that can be dried at the same time. Bale drying tends to be applied more on farms that want their forage partly as grass silage and partly as barn-dried hay

Economic Aspects of Physical Intra-Row Weed Control in Seeded Onions

The paper presents a model to calculate the costs for weed control in organic row crops. The model makes it possible to analyse the economic consequences of different weed control strategies in row crops. Particularly the time needed for hand-weeding had a strong impact on the costs

Automatische Lenksysteme zur Unterstützung der mechanischen Beikrautregulierung

Weed management without herbicides in production of field vegetables is very time consuming and therefore costly. After every mechanical treatment a weeding by hand is necessary for a satisfactory weed control. To minimize the weeding automatic steering systems connected to a shifting frame can support the mechanical weeding by making it more precise and reducing the remaining weeds in the row. Field studies in the year 2016 showed advantages and disadvantages of the systems