Coupled human and natural system dynamics as key to the sustainability of Lake Victoria's ecosystem services

Downing, Andrea S.; van Nes, Egbert H.; Balirwa, John S.; Beuving, Joost; Bwathondi, P.O.J.; Chapman, Lauren J.; Cornelissen, Ilse J. M.; Cowx, Iain G.; Goudswaard, Kees P. C.; Hecky, Robert E.; Janse, Jan H.; Janssen, Annette B. G.; Kaufman, Les; Kishe-Machumu, Mary A.; Kolding, Jeppe; Ligtvoet, Willem; Mbabazi, Dismas; Medard, Modesta; Mkumbo, Oliva C.; Mlaponi, Enock; ... (2014). Coupled human and natural system dynamics as key to the sustainability of Lake Victoria's ecosystem services. Ecology and Society, 19(4) Resilience Alliance Publications 10.5751/ES-06965-190431

[img]
Preview
Text
ES-2014-6965.pdf - Published Version
Available under License Publisher holds Copyright.

Download (438kB) | Preview

East Africa’s Lake Victoria provides resources and services to millions of people on the lake’s shores and abroad. In particular, the lake’s fisheries are an important source of protein, employment, and international economic connections for the whole region. Nonetheless, stock dynamics are poorly understood and currently unpredictable. Furthermore, fishery dynamics are intricately connected to other supporting services of the lake as well as to lakeshore societies and economies. Much research has been carried out piecemeal on different aspects of Lake Victoria’s system; e.g., societies, biodiversity, fisheries, and eutrophication. However, to disentangle drivers and dynamics of change in this complex system, we need to put these pieces together and analyze the system as a whole. We did so by first building a qualitative model of the lake’s social-ecological system. We then investigated the model system through a qualitative loop analysis, and finally examined effects of changes on the system state and structure. The model and its contextual analysis allowed us to investigate system-wide chain reactions resulting from disturbances. Importantly, we built a tool that can be used to analyze the cascading effects of management options and establish the requirements for their success. We found that high connectedness of the system at the exploitation level, through fisheries having multiple target stocks, can increase the stocks’ vulnerability to exploitation but reduce society’s vulnerability to variability in individual stocks. We describe how there are multiple pathways to any change in the system, which makes it difficult to identify the root cause of changes but also broadens the management toolkit. Also, we illustrate how nutrient enrichment is not a self-regulating process, and that explicit management is necessary to halt or reverse eutrophication. This model is simple and usable to assess system-wide effects of management policies, and can serve as a paving stone for future quantitative analyses of system dynamics at local scales.

Item Type:

Journal Article (Review Article)

Division/Institute:

08 Faculty of Science > Department of Biology > Institute of Ecology and Evolution (IEE)
08 Faculty of Science > Department of Biology > Institute of Ecology and Evolution (IEE) > Aquatic Ecology

UniBE Contributor:

Seehausen, Ole and van Rijssel, Jacobus Cornelis

Subjects:

500 Science > 570 Life sciences; biology

ISSN:

1708-3087

Publisher:

Resilience Alliance Publications

Language:

English

Submitter:

Marcel Häsler

Date Deposited:

20 Jul 2015 16:06

Last Modified:

20 Jul 2015 16:06

Publisher DOI:

10.5751/ES-06965-190431

BORIS DOI:

10.7892/boris.70363

URI:

https://boris.unibe.ch/id/eprint/70363

Actions (login required)

Edit item Edit item
Provide Feedback