- Bodo D. Wilts (1)
- Eva E. Deinum (1)
- Villads Egede Johansen (1)
- Simon H. Tindemans (1)
- Raditijo Hamidjaja (1)
- Nico Heerink (1)
- Colin J. Ingham (1)
- Tom Kuhlman (1)
- J. Lindeboom (1)
- Bela M. Mulder (1)
- Michael Mario Sherlock (1)
- Els Oosterink (1)
- Nico Polman (1)
- Stijn Reinhard (1)
- Torben Sølbeck Rasmussen (1)
- Alberto Tacón (1)
- Rong Tan (1)
- Silvia Vignolini (1)
Self-organizing processes in urban green commons. The case of the Angachilla wetland, Valdivia-Chile
Correa, Heidy ; Blanco-Wells, Gustavo ; Barrena, José ; Tacón, Alberto - \ 2018
International Journal of the Commons 12 (2018)1. - ISSN 1875-0281 - p. 573 - 595.
Chile - Self-organization - Social-ecological systems - Urban green commons - Wetlands
This article focuses on self-organizing processes in contested urban social-ecological systems. It analyzes a wetland conservation program and civic management effort in the Angachilla sector of the city of Valdivia, Chile in a 15-year time frame. The aim is to understand what triggers collective actions and self-organization in the attempts of preserving an urban green common. The study uses a qualitative approach based on action-research methodologies. It examines key variables influencing self-organizing processes; including social-environmental crises, governance vacuums, wetland valuation, and leadership. It also discusses collective strategies for the transformation of negative feedback loops, such as norms and regulations detrimental to wetland protection, and those related to resistance to change of wetland surface area due to unregulated urbanization. From an Urban Green Commons perspective, this work illustrates the complexity of dealing with contested nature, making it a resource difficult to govern collectively given all the different interests and values in place. It also shows that there have been successful periods of active wetland management that have influenced active democratic processes regarding land use and land use change in the city.
Genetic manipulation of structural color in bacterial colonies
Johansen, Villads Egede ; Catón, Laura ; Hamidjaja, Raditijo ; Oosterink, Els ; Wilts, Bodo D. ; Rasmussen, Torben Sølbeck ; Sherlock, Michael Mario ; Ingham, Colin J. ; Vignolini, Silvia - \ 2018
Proceedings of the National Academy of Sciences of the United States of America 115 (2018)11. - ISSN 0027-8424 - p. 2652 - 2657.
Disorder - Flavobacteria - Genetics - Self-organization - Structural color
Naturally occurring photonic structures are responsible for the bright and vivid coloration in a large variety of living organisms. Despite efforts to understand their biological functions, development, and complex optical response, little is known of the underlying genes involved in the development of these nanostructures in any domain of life. Here, we used Flavobacterium colonies as a model system to demonstrate that genes responsible for gliding motility, cell shape, the stringent response, and tRNA modification contribute to the optical appearance of the colony. By structural and optical analysis, we obtained a detailed correlation of how genetic modifications alter structural color in bacterial colonies. Understanding of genotype and phenotype relations in this system opens the way to genetic engineering of on-demand living optical materials, for use as paints and living sensors.
How selective severing by katanin promotes order in the plant cortical microtubule array
Deinum, Eva E. ; Tindemans, Simon H. ; Lindeboom, J. ; Mulder, Bela M. - \ 2017
Proceedings of the National Academy of Sciences of the United States of America 114 (2017)27. - ISSN 0027-8424 - p. 6942 - 6947.
Cortical microtubule array - Katanin - Microtubule dynamics - Plant cell biology - Self-organization
Plant morphogenesis requires differential and often asymmetric growth. A key role in controlling anisotropic expansion of individual cells is played by the cortical microtubule array. Although highly organized, the array can nevertheless rapidly change in response to internal and external cues. Experiments have identified the microtubule-severing enzyme katanin as a central player in controlling the organizational state of the array. Katanin action is required both for normal alignment and the adaptation of array orientation to mechanical, environmental, and developmental stimuli. How katanin fulfills its controlling role, however, remains poorly understood. On the one hand, from a theoretical perspective, array ordering depends on the "weeding out" of discordant microtubules through frequent catastrophe-inducing collisions among microtubules. Severing would reduce average microtubule length and lifetime, and consequently weaken the driving force for alignment. On the other hand, it has been suggested that selective severing at microtubule crossovers could facilitate the removal of discordant microtubules. Here we show that this apparent conflict can be resolved by systematically dissecting the role of all of the relevant interactions in silico. This procedure allows the identification of the sufficient and necessary conditions for katanin to promote array alignment, stresses the critical importance of the experimentally observed selective severing of the "crossing" microtubule at crossovers, and reveals a hitherto not appreciated role for microtubule bundling. We show how understanding the underlying mechanism can aid with interpreting experimental results and designing future experiments.
Public and self-organized land readjustment in rural China − A comparison
Tan, Rong ; Heerink, Nico - \ 2017
Journal of Rural Studies 53 (2017). - ISSN 0743-0167 - p. 45 - 57.
China - Eminent domain - Land readjustment - Self-organization - Transaction costs
The role of land readjustment for urban and rural development has attracted more and more attention worldwide. Research on how land readjustment can be organized most effectively, however, is still in its infancy. This paper firstly develops a framework for comparing different organization modes of land readjustment based on transaction cost economics. It then introduces and compares two different modes of land readjustment that have recently been developed in China, i.e., a public mode and a self-organized mode. We argue, and provide evidence from two case studies in Zhejiang Province and in Sichuan Province, that the (mis)fit between the transaction attributes of land readjustment and the adopted readjustment mode greatly affects their performance. Our findings are intended to serve as a reference both for further research and for policy making on land readjustment.
Governance of ecosystem services on small islands : Three contrasting cases for St. Eustatius in the Dutch Caribbean
Polman, Nico ; Reinhard, Stijn ; Bets, L.K.J. van; Kuhlman, Tom - \ 2016
Island Studies Journal 11 (2016)1. - ISSN 1715-2593 - p. 265 - 284.
Caribbean - Ecosystem services - Environment - Governance - Self-organization - Small island
Natural ecosystems provide an attractive focus for tourism on small islands. However, at the same time tourism and other human actions can be detrimental to these ecosystems especially because governance of the ecosystem may be difficult due to the limited resilience of small island ecosystems. In this paper, we focus on the conditions under which self-governance will be the appropriate governance mechanism of ecosystem services on small islands. We apply Ostrom’s (2009) framework for common-pool resources in a social-ecological system, and select the relevant indicators for small islands. We scored these indicators for three cases (environmental issues) in St. Eustatius, a Caribbean island under Dutch rule. These cases show that self-organization of ecosystem services is not an outcome easily achieved. The unevenly distributed benefits of potential measures are found to decrease community support of measures that could reinforce these ecosystem services.