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de Toro A.,Swedish University of Agricultural Sciences | Gunnarsson C.,Swedish Institute of Agricultural and Environmental Engineering | Lundin G.,Swedish Institute of Agricultural and Environmental Engineering | Jonsson N.,Swedish Institute of Agricultural and Environmental Engineering
Biosystems Engineering | Year: 2012

This study simulated 30 years of harvesting operations on an hourly basis with a harvesting model linked to a grain moisture model capable of predicting the moisture content of standing ripe wheat using historical weather data from Stockholm, Sweden, as input, in order to assess the effects of weather on cereal harvesting costs. Several combinations of harvester size and grain moisture ceiling were assessed on three cereal areas in terms of overall costs (machine + labour + timeliness + drying) and their annual variations.The main findings obtained by simulation and valid for regions with similar climate and agricultural conditions to the studied region were that: (a) available combining time was highly dependent on grain moisture ceiling, which showed large annual variation, e.g. a moisture ceiling of 21% (w.b.) was related to a potential harvesting time of 65% and a standard deviation of 24% (n = 30 years); (b) in order to complete harvesting operations in most years, it was necessary to operate at a moisture ceiling of 22-24% (w.b.), however, the average moisture content of the harvested grain was much lower, about 17-18%; (c) overall harvesting costs were estimated at approx €140 ha -1 for those systems performing relatively well, i.e. with a daily harvesting capacity of 4-5% of the cereal area and operating at a moisture ceiling of 22-24% (w.b.); and (d) the main sources of annual cost variation were firstly the timeliness costs and secondly the drying costs. © 2012 IAgrE. Source

Coppola L.,Marche Polytechnic University | Pilar Castillo M.D.,Swedish Institute of Agricultural and Environmental Engineering | Vischetti C.,Marche Polytechnic University
Pest Management Science | Year: 2011

Background: The composition and properties of a biomixture used in a biobed are decisive for pesticide sorption and degradation. This study was performed to investigate the capability of compost-based substrates in mixtures with citrus peel and vine branch straw and peat-based substrates in mixtures with soil and vine branch straw at different levels in order to degrade isoproturon and bentazone. Results: Dissipation and mineralisation rates of both pesticides were determined, and metabolic activity was followed as respiration. Compost-based substrates showed faster pesticide dissipation in the presence of lignocellulosic materials, as in garden compost and vine branch straw. The increasing content of vine branch straw in peat-based substrates does not seem to affect dissipation of the parent compounds. Low mineralisation rate was observed in all treatments. Conclusion: Higher pesticide degradation was observed in the lignocellulosic substrates, probably because of the development of lignin-degrading microorganisms which have shown to be robust and are able to degrade recalcitrant pesticides. © 2010 Society of Chemical Industry. Source

Granhall U.,Swedish University of Agricultural Sciences | Welsh A.,Swedish University of Agricultural Sciences | Throback I.N.,Swedish University of Agricultural Sciences | Hjort K.,Sodertorn University College | And 2 more authors.
Journal of Industrial Microbiology and Biotechnology | Year: 2010

Paper mills processing recycled paper suffer from biofouling causing problems both in the mill and final product. The total bacterial community composition and identification of specific taxa in the process water and biofilms at the stock preparation and paper machine areas in a mill with recycled paper pulp was described by using a DNA-based approach. Process water in a similar mill was also analyzed to investigate if general trends can be found between mills and over time. Bacterial community profiles, analyzed by terminal-restriction fragment length polymorphism (T-RFLP), in process water showed that the dominant peaks in the profiles were similar between the two mills, although the overall composition was unique for each mill. When comparing process water and biofilm at different locations within one of the mills, we observed a separation according to location and sample type, with the biofilm from the paper machine being most different. 16S rRNA gene clone libraries were generated and 404 clones were screened by RFLP analysis. Grouping of RFLP patterns confirmed that the biofilm from the paper machine was most different. A total of 99 clones representing all RFLP patterns were analyzed, resulting in sequences recovered from nine bacterial phyla, including two candidate phyla. Bacteroidetes represented 45% and Actinobacteria 23% of all the clones. Sequences with similarity to organisms implicated in biofouling, like Chryseobacterium spp. and Brevundimonas spp., were recovered from all samples even though the mill had no process problems during sampling, suggesting that they are part of the natural paper mill community. Moreover, many sequences showed little homology to as yet uncultivated bacteria implying that paper mills are interesting for isolation of new organisms, as well as for bioprospecting. © Society for Industrial Microbiology 2010. Source

Onneby K.,Swedish University of Agricultural Sciences | Hakansson S.,Swedish University of Agricultural Sciences | Pizzul L.,Swedish Institute of Agricultural and Environmental Engineering | Stenstrom J.,Swedish University of Agricultural Sciences
Biodegradation | Year: 2014

The use of pesticides on sandy soils and on many non-agricultural areas entails a potentially high risk of water contamination. This study examined leaching of the herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA) after bioaugmentation in sand with differently formulated and stored Sphingobium sp. T51 and at different soil moisture contents. Dry formulations of Sphingobium sp. T51 were achieved by either freeze drying or fluidised bed drying, with high initial cell viability of 67-85 %. Storage stability of T51 cells was related to formulation excipient/carrier and storage conditions. Bacterial viability in the fluidised bed-dried formulations stored at 25 °C under non-vacuum conditions was poor, with losses of at least 97 % within a month. The freeze-dried formulations could be stored substantially longer, with cell survival rates of 50 %, after 6 months of storage at the same temperature under partial vacuum. Formulated and long-term stored Sphingobium cells maintained their MCPA degradation efficacy and reduced MCPA leaching as efficiently as freshly cultivated cells, by at least 73 % when equal amounts of viable cells were used. The importance of soil moisture for practical field bioaugmentation techniques is discussed. © 2013 Springer Science+Business Media Dordrecht. Source

Spangberg J.,Swedish University of Agricultural Sciences | Tidaker P.,Swedish Institute of Agricultural and Environmental Engineering | Jonsson H.,Swedish University of Agricultural Sciences
Science of the Total Environment | Year: 2014

Human excreta are potential sources of plant nutrients, but are today usually considered a waste to be disposed of. The requirements on wastewater treatment plants (WWTPs) to remove nitrogen and phosphorus are increasing and to meet these requirements, more energy and chemicals are needed by WWTPs. Separating the nutrient-rich wastewater fractions at source and recycling them to agriculture as fertiliser is an alternative to removing them at the WWTP. This study used life cycle assessment methodology to compare the environmental impact of different scenarios for recycling the nutrients in the human excreta as fertiliser to arable land or removing them in an advanced WWTP. Three scenarios were assessed. In blackwater scenario, blackwater was source-separated and used as fertiliser. In urine scenario, the urine fraction was source-separated and used as fertiliser and the faecal water treated in an advanced WWTP. In NP scenario, chemical fertiliser was used as fertiliser and the toilet water treated in an advanced WWTP. The emissions from the WWTP were the same for all scenarios. This was fulfilled by the enhanced reduction in the WWTP fully removing the nutrients from the excreta that were not source-separated in the NP and urine scenarios. Recycling source-separated wastewater fractions as fertilisers in agriculture proved efficient for conserving energy and decreasing global warming potential (GWP). However, the blackwater and urine scenarios had a higher impact on potential eutrophication and potential acidification than the WWTP-chemical fertiliser scenario, due to large impacts by the ammonia emitted from storage and after spreading of the fertilisers. The cadmium input to the arable soil was very small with urine fertiliser. Source separation and recycling of excreta fractions as fertiliser thus has potential for saving energy and decreasing GWP emissions associated with wastewater management. However, for improved sustainability, the emissions from storage and after spreading of these fertilisers must decrease. © 2014. Source

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