| 1. |
- Jerneck, Anne, et al.
(författare)
-
Theoretical and Methodological Pluralism in Sustainability Science
- 2019
-
Ingår i: Framing in Sustainability Science : Theoretical and Practical Approaches - Theoretical and Practical Approaches. - Singapore : Springer Singapore. - 9789811390609 - 9789811390616 ; , s. 17-33
-
Bokkapitel (refereegranskat)abstract
- Sustainability science is an integrative scientific field embracing not only complementary but also contradictory approaches and perspectives for dealing with an array of sustainability challenges.In this chapter we distinguish between pluralism and unification as two main and distinctly different approaches to knowledge integration in sustainability science. To avoid environmental determinism, functionalism, or overly firm reliance on rational choice theory, we have reason to promote pluralism as a way to better tackle sustainability challenges. In particular we emphasise two main benefits of taking a pluralist approach in research: it opens up for collaboration, and ensures a more theoretically informed understanding of society.After a brief introduction to how we interpret the field of sustainability science, we discuss ontology, epistemology and ways of understanding society based on social science theory. We make three contributions. First, we identify important reasons for the incommensurability between the social and natural sciences, and propose remedies for how to overcome some of the difficulties in integrative research. Second, by suggesting a frame that we call ‘social fields and natural systems’ we show how sustainability science will benefit from drawing more profoundly on – and thus more adequately incorporate – a social science understanding of society. As such, the frame is a foundation for pluralism. Third, by suggesting a new theoretical typology, we show how sustainability visions and pathways are associated with particular theoretical and methodological perspectives in geography, political science, and sociology; and how that matters for research and politics addressing sustainability challenges. The typology can be used as a thinking tool to frame and reframe research.
|
|
| 2. |
- Wilen, Britt-Marie, 1966, et al.
(författare)
-
Dynamics in flocculation and settling properties studied at a full scale activated sludge plant
- 2010
-
Ingår i: Water Environment Research. - 1061-4303 .- 1554-7531. ; 82:2, s. 155-168
-
Tidskriftsartikel (refereegranskat)abstract
- A comprehensive study of the dynamics in settling and flocculation properties at a full scale activated sludge treatment plant with secondary settlers operated at their maximum capacity is presented. An extensive set of process data was analysed to assess physical parameters affecting the capacity and performance of the secondary settlers. There was a large variation in the settling and compaction properties and they changed quickly due to the short sludge age. Even though the flocculation properties changed throughout the year they were generally improved during the summer with lower values of effluent turbidity and effluent suspended solids concentration. The shear sensitivity, which is a measure of floc stability, was higher during the winter when the water temperatures were lower. The sludge floc morphology had in general a different internal structure with more round microbial colonies during the warmer summer months and a more net-like open structure during the winter.
|
|
| 3. |
- Wilen, Britt-Marie, 1966, et al.
(författare)
-
Microbial community structure in activated sludge floc analysed by fluorescence in situ hybridization and its relation to floc stability
- 2008
-
Ingår i: Water Research. - : Elsevier BV. - 0043-1354 .- 1879-2448. ; 42:8-9, s. 2300-2308
-
Tidskriftsartikel (refereegranskat)abstract
- The efficiency of activated sludge treatment plants is dependent on the solid–liquid separation properties of the activated sludge. A critical parameter is the stability of the microbial flocs. Weak flocs deflocculate easily leaving increased concentrations of suspended solids in the effluent. The knowledge about how different bacteria are attached to the flocs and their influence on the bioflocculation is limited. In this study, the deflocculation of different phylogenetic groups of bacteria in activated sludge from a full scale plant was investigated. The experiments were carried out by using a shear method where the sludge flocs are deflocculated under controlled shear conditions. The degree of deflocculation was measured as increase in turbidity of the supernatant. Identification and quantification of the microbial community structure of both total activated sludge and deflocculated bacteria were conducted with group-specific gene probes for broad groups of bacteria (Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria and Actinobacteria) and fluorescence in situ hybridization (FISH). The microbial community structure of the deflocculated bacteria was different compared to the total activated sludge with a higher abundance of Gammaproteobacteria in the supernatant indicating that different groups of bacteria are bound with different strength to the floc surface. The results show that the bacteria in the outer parts of the flocs are relatively loosely bound to the floc matrix and can be easily eroded from the surface when exposed to shear.
|
|
| 4. |
- Wilen, Britt-Marie, 1966, et al.
(författare)
-
Relationship between floc composition and flocculation and settling properties studied at a full scale activated sludge plant
- 2008
-
Ingår i: Water Research. - 0043-1354 .- 1879-2448. ; 42:16, s. 4404-4418
-
Tidskriftsartikel (refereegranskat)abstract
- The variation in activated sludge floc composition, flocculation and settling properties were studied at a full scale plant over a two year period. A comprehensive set of process parameters was analysed and related to the floc properties to increase the understanding of the factors affecting floc formation. The composition of the activated sludge showed a seasonal change with higher concentrations of extractable extracellular polymeric substances (EPS) during the winter months. The protein content of the total sludge and EPS increased significantly during the winter. This coincided with higher effluent suspended solids concentrations and increased shear sensitivity of the sludge flocs. Only poor correlations between EPS contents and stirred sludge volume index (SSVI) could be observed. High iron concentrations in the sludge due to dosage of iron salt to precipitate phosphorus was found to have a negative impact on the settling and compaction properties of the sludge, whereas it had a positive impact on floc stability. Higher organic loading due to by-passed primary settlers lead to improved settling and compaction properties.
|
|
| 5. |
- Yarime, Masaru, et al.
(författare)
-
Establishing sustainability science in higher education institutions: towards an integration of academic development, institutionalization, and stakeholder collaborations
- 2012
-
Ingår i: Sustainability Science. - : Springer Science and Business Media LLC. - 1862-4057 .- 1862-4065. ; 7, s. 101-113
-
Tidskriftsartikel (refereegranskat)abstract
- The field of sustainability science aims to understand the complex and dynamic interactions between natural and human systems in order to transform and develop these in a sustainable manner. As sustainability problems cut across diverse academic disciplines, ranging from the natural sciences to the social sciences and humanities, interdisciplinarity has become a central idea to the realm of sustainability science. Yet, for addressing complicated, real-world sustainability problems, interdisciplinarity per se does not suffice. Active collaboration with various stakeholders throughout society-transdisciplinarity-must form another critical component of sustainability science. In addition to implementing interdisciplinarity and transdisciplinarity in practice, higher education institutions also need to deal with the challenges of institutionalization. In this article, drawing on the experiences of selected higher education academic programs on sustainability, we discuss academic, institutional, and societal challenges in sustainability science and explore the potential of uniting education, research and societal contributions to form a systematic and integrated response to the sustainability crisis.
|
|
