26 research outputs found
Organisationskultur. Eine Konkretisierung aus systemtheoretischer Perspektive
Kühl S. Organisationskultur. Eine Konkretisierung aus systemtheoretischer Perspektive. Managementforschung. 2018;28(1):7-35.Die Bestimmung des Verhältnisses von Informalität und Organisationskultur bereitet in der Organisationstheorie Schwierigkeiten. Das liegt daran, dass der Begriff Informalität häufig stillschweigend durch den Begriff der Organisationskultur ersetzt wurde, ohne dass dafür eine präzise, abgrenzungsscharfe Definition vorgenommen worden wäre. Unter Rückgriff auf Überlegungen von Dario Rodríguez argumentiert dieser Artikel, dass die beiden Begriffe Organisationskultur und Informalität das gleiche Phänomen bezeichnen: die nichtentschiedenen Entscheidungsprämissen einer Organisation. Dabei wird systematisch zwischen „unentscheidbaren Entscheidungsprämissen“ und „prinzipiell entscheidbaren, aber nicht entschiedenen Entscheidungsprämissen“ unterschieden. Es wird gezeigt, wie sich mit einer präzisen Bestimmung über das Konzept der Entscheidungsprämissen Ordnung in die „wilden Merkmallisten“ der Literatur sowohl über Informalität als auch Organisationskultur bringen lässt und empirische Phänomene genauer erfasst werden können
Casual observations, random musings and wild extrapolations based on some actual data on the impact of invasive tunicates to eelgrass
Tunicates, more commonly known as sea squirts, can grow as a solitary organism or as part of extensive colonies. Tunicates are more frequently associated with hard substrate, but a number of invasive tunicate species have now been found to colonize eelgrass. We attempted to quantify what impact these tunicates may have on eelgrass. Using HOBO light sensors, we measured the ability of 5 different tunicate species to block light. In several ponds on Martha\u27s Vineyard, we measured a number of eelgrass parameters (canopy height, leaves per shoot, growth rate, tissue sugar concentration) in both plants without tunicates and plants heavily colonized by tunicates. We found that all species of tunicates tested blocked between 70-85% of ambient light. We found that plants colonized by tunicates had fewer leaves per shoot, smaller canopy height, lower growth rates, but high tissue sugar concentrations than plants not colonized by tunicates. In 2013, we attempted to assess the extent of the problem, by coordinating a study of 19 different sampling locations from New Jersey to Canada. Particiapnts sampled eelgrass meadows and documented the presence/absence of tunicates, identified tunicate species, estimated the extent of the colonization, measured eelgrass shoot density and canopy height and in some locations collected water temperature. Invasive tunicates were observed on eelgrass in all meadows sampled from Newfoundland to New Jersey, though the number of species present and the extent of the colonization varied greatly
Biogeographical patterns of tunicates utilizing eelgrass as substrate in the western North Atlantic between 39 degrees and 47 degrees north latitude (New Jersey to Newfoundland)
© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Carmen, M. R., Colarusso, P. D., Neckles, H. A., Bologna, P., Caines, S., Davidson, J. D. P., Evans, N. T., Fox, S. E., Grunden, D. W., Hoffman, S., Ma, K. C. K., Matheson, K., McKenzie, C. H., Nelson, E. P., Plaisted, H., Reddington, E., Schott, S., & Wong, M. C. Biogeographical patterns of tunicates utilizing eelgrass as substrate in the western North Atlantic between 39 degrees and 47 degrees north latitude (New Jersey to Newfoundland). Management of Biological Invasions, 10(4), (2019): 602-616, doi: 10.3391/mbi.2019.10.4.02.Colonization of eelgrass (Zostera marina L.) by tunicates can lead to reduced plant growth and survival. Several of the tunicate species that are found on eelgrass in the northwest Atlantic are highly aggressive colonizers, and range expansions are
predicted in association with climate-change induced increases in seawater temperature. In 2017, we surveyed tunicates within eelgrass meadows at 33 sites from New Jersey to Newfoundland. Eight tunicate species were identified colonizing eelgrass, of which four were non-native and one was cryptogenic. The most common species (Botrylloides violaceus and Botryllus schlosseri) occurred from New York to Atlantic Canada. Tunicate faunas attached to eelgrass were less diverse north of Cape Cod, Massachusetts. Artificial substrates in the vicinity of the eelgrass meadows generally supported more tunicate species than did the eelgrass, but fewer species co-occurred in northern sites than southern sites. The latitudinal gradient in tunicate diversity corresponded to gradients of summertime sea surface temperature and traditional biogeographical zones in the northwest Atlantic, where Cape Cod represents a transition between cold-water and warm-water invertebrate faunas. Tunicate density in the eelgrass meadows was low, ranging generally from 1–25% cover of eelgrass shoots, suggesting that space availability does not
currently limit tunicate colonization of eelgrass. This survey, along with our 2013 survey, provide a baseline for identifying future changes in tunicate distribution and abundance in northwest Atlantic eelgrass meadows.We thank Benedikte Vercaemer, Dann Blackwood, Jonathon Seaward, Dani Cleary, Sam Hartman, Kim Manzo, and Jason Havelin for field assistance. Thank you too to Alicia Grimaldi for map construction and Page Valentine for constructively reviewing the manuscript. Thank you to the Community Preservation Committee of Oak Bluffs, Massachusetts, and the USGS-WHOI
Cooperative Agreement for funding (Carman). All data used in this paper are publicly available through USGS ScienceBase at https://doi.org/10.5066/P9GDBDFQ. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government