1,283 research outputs found
Servitization for consumer products:an empirical exploration of challenges and benefits for supply chain partners
Purpose To increase sustainability of their products and enable new business opportunities, manufacturers explore servitization in consumer markets. Yet, the literature has not addressed this development. This study is one of the first to investigate the challenges and benefits for manufacturers and their supply chains when engaging in business-to-consumer (B2C) servitization. Design/methodology/approach The study explores two unique cases of manufacturers of complex consumer products that aim to extend their service offerings to the end-users. Data were collected via semi-structured interviews, observations and secondary data. Findings First, the authors identify two factors as prerequisites for a servitized set-up: internal collaboration within the manufacturer and product characteristics (e.g. product complexity). Second, the authors identify the network as an important factor for B2C servitization, which includes the triadic set-up between manufacturer, installer and consumer. Third, the authors identify moderating institutional settings, such as regulations and consumer needs. Originality/value This research elaborates existing B2B servitization theory into an empirically informed theoretical framework for B2C contexts. It expands the view on servitization by introducing the network perspective to service a large number of geographically dispersed customers
What is the influence on water quality in temperate eutrophic lakes of a reduction of planktivorous and benthivorous fish? A systematic review protocol
Background: In lakes that have become eutrophic due to sewage discharges or nutrient runoff from land, problems such as algal blooms and oxygen deficiency often persist even when nutrient supplies have been reduced. One reason is that phosphorus stored in the sediments can exchange with the water. There are indications that the high abundance of phytoplankton, turbid water and lack of submerged vegetation seen in many eutrophic lakes may represent a semi-stable state. For that reason, a shift back to more natural clear-water conditions could be difficult to achieve. In some cases, though, temporary mitigation of eutrophication-related problems has been accomplished through biomanipulation: stocks of zooplanktivorous fish have been reduced by intensive fishing, leading to increased populations of phytoplankton-feeding zooplankton. Moreover, reduction of benthivorous fish may result in lower phosphorus fluxes from the sediments. An alternative to reducing the dominance of planktivores and benthivores by fishing is to stock lakes with piscivorous fish. These two approaches have often been used in combination. The implementation of the EU Water Framework Directive has recently led to more stringent demands for measures against eutrophication, and a systematic review could clarify whether biomanipulation is efficient as a measure of that kind. Methods: The review will examine primary field studies of how large-scale biomanipulation has affected water quality and community structure in eutrophic lakes or reservoirs in temperate regions. Such studies can be based on comparison between conditions before and after manipulation, on comparison between treated and non-treated water bodies, or both. Relevant outcomes include Secchi depth, concentrations of oxygen, nutrients, suspended solids and chlorophyll, abundance and composition of phytoplankton, zooplankton and fish, and coverage of submerged macrophytes.A Systematic review to this article was published on 22 May 2015: ernes, C., Carpenter, S.R., Gårdmark, A. et al. What is the influence of a reduction of planktivorous and benthivorous fish on water quality in temperate eutrophic lakes? A systematic review. Environ Evid 4, 7 (2015). DOI: 10.1186/s13750-015-0032-9Mistr
The role of fish stock management in eutrophication control in shallow Lakes in The Netherlands.
No negative effects of a multi-factorial, intensified treatment on self-reported health status, treatment satisfaction, and diabetes-related distress in screen-detected type 2 diabetes patients. The ADDITION-Netherlands study
Combined and single effects of pesticide carbaryl and toxic microcystis aeruginosa on the life history of Daphnia pulicaria
Parasitic chytrids could promote copepod survival by mediating material transfer from inedible diatoms
Diatoms form large spring blooms in lakes and oceans, providing fuel for higher trophic levels at the start of the growing season. Some of the diatom blooms, however, are not grazed by filter-feeding zooplankton like Daphnia due to their large size. Several of these large diatoms are susceptible to chytrid infections. Zoospores of chytrids appeared to be excellent food for Daphnia, both in terms of size, shape, and quality (PUFAs and cholesterol). Thus, zoospores of chytrids can bridge the gap between inedible diatoms and Daphnia. In order to examine the effects of diatoms and chytrids on the survival of copepods, we performed one grazing and one survival experiment. The grazing experiment revealed that the diatom, Asterionella formosa, was not grazed by the copepod, Eudiaptomus gracilis, even after being infected by the chytrid Zygorhizidium planktonicum. However, carbon and nitrogen concentrations were significantly reduced by E. gracilis only when A. formosa was infected by Z. planktonicum, indicating that the chytrids might facilitate material transfer from inedible diatoms to the copepods. The survival experiment revealed that E. gracilis lived shorter with A. formosa than with the cryptophyta Cryptomonas pyrenoidifera. However, the survival of E. gracilis increased significantly in the treatment where A. formosa cells were infected by Z. planktonicum. Since E. gracilis could not graze A. formosa cells due to their large colonial forms, E. gracilis may acquire nutrients by grazing on the zoospores, and were so able to survive in the presence of the A. formosa. This provides new insights into the role of parasitic fungi in aquatic food webs, where chytrids may improve copepod survival during diatom blooms.
Chytrid epidemics may increase genetic diversity of a diatom spring-bloom
Contrary to expectation, populations of clonal organisms are often genetically highly diverse. In phytoplankton, this diversity is maintained throughout periods of high population growth (that is, blooms), even though competitive exclusion among genotypes should hypothetically lead to the dominance of a few superior genotypes. Genotype-specific parasitism may be one mechanism that helps maintain such high-genotypic diversity of clonal organisms. Here, we present a comparison of population genetic similarity by estimating the beta-dispersion among genotypes of early and peak bloom populations of the diatom Asterionella formosa for three spring-blooms under high or low parasite pressure. The Asterionella population showed greater beta-dispersion at peak bloom than early bloom in the 2 years with high parasite pressure, whereas the within group dispersion did not change under low parasite pressure. Our findings support that high prevalence parasitism can promote genetic diversification of natural populations of clonal hosts
Resuspensie, sedimentatie en lichtklimaat in de Breukeleveense Plas.
Opwerveling van slib kan in ondiepe Nederlandse oppervlaktewateren een aanzienlijke bijdrage leveren aan de uitdoving van het licht onder water. In 1989 werd gepoogd om door Actief Biologisch Beheer, door verwijdering van een groot deel van de planktivore en benthivore visstand, het doorzicht in de Breukeleveense Bias te vergroten. Deze ingreep gaf echter geen verbetering in het onder water lichtklimaat te zien. Als één van de belangrijkste oorzaken voor het uitblijven van succes wordt de door de wind veroorzaakte opwerveling van bodemslib gezien. Deze studie beschrijft het onder water lichtklimaat in de plas. Het onderzoek was gericht op de bijdrage van verschillende componenten en de invloed van wind op de uitdoving van licht en de vermindering van het doorzicht. De extinctiecoëfficiënten en het doorzicht zijn geschat met behulp van het model UITZICHT. Met dit model werd inzicht verkregen in de bijdrage van verschillende componenten aan de extinctie en het doorzicht. In de plas blijken algen (ca. 50%) en detritus (ca. 25%) in hoge mate verantwoordelijk voor de uitdoving van licht. Met het model DYNHX kon worden afgeleid wat de bijdrage van geresuspendeerd bodemslib aan de extinctie en de afname van het doorzicht is. In het slibrijke zuidwesten van de plas is de bijdrage aan de extinctie gemiddeld 25% resulterend in een afname van het doorzicht van gemiddeld 0,44 tot 0,30 m. In het meer zanderige noordoosten is de bijdrage van resuspensie aan de extinctie gemiddeld 17%, het doorzicht wordt hierdoor gereduceerd van gemiddeld 0,41 tot 0,32 m. In perioden met hevige wind kunnen de bijdragen van resuspensie aan de extinctie oplopen tot 72% in het zuidwesten en tot 44°/o in het noordoosten van de plas. Tijdens deze perioden blijkt het doorzicht gereduceerd te worden tot 0,13 m in het zuidwesten en tot 0,22 m in het noordoosten van de plas. Voor een verbetering van het doorzicht zullen naast reductie van de planktivore en benthivore visstand aanvullende maatregelen voor de reductie van de slibopwerveling nodig zijn aangezien baggeren, vanwege de extreem hoge kosten, geen reële oplossing blijkt
Zwemlust: mechanismen van helder worden en van overgang naar de troebele toestand zes jaar na biomanipulatie.
Macrophyte-related shifts in the nitrogen and phosphorus contents of the different trophic levels in a biomanipulated shallow lake
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