Monica Hammer

Ecosystem services generated by fish populations

In this paper, we review the role of fish populations in generating ecosystem services based on documented ecological functions and human demands of fish. The ongoing overexploitation of global fish resources concerns our societies, not only in terms of decreasing fish populations important for consumption and recreational activities. Rather, a number of ecosystem services generated by fish populations are also at risk, with consequences for biodiversity, ecosystem functioning, and ultimately human welfare. Examples are provided from marine and freshwater ecosystems, in various parts of the world, and include all life-stages of fish. Ecosystem services are here defined as fundamental services for maintaining ecosystem functioning and resilience, or demand-derived services based on human values. To secure the generation of ecosystem services from fish populations, management approaches need to address the fact that fish are embedded in ecosystems and that substitutions for declining populations and habitat losses, such as fish stocking and nature reserves, rarely replace losses of all services.

Governance of Water Resources in the Phase of Change : A Case Study of the Implementation of the EU Water Framework Directive in Sweden

In this article, focusing on the ongoing implementation of the EU Water Framework Directive, we analyze some of the opportunities and challenges for a sustainable governance of water resources from an ecosystem management perspective. In the face of uncertainty and change, the ecosystem approach as a holistic and integrated management framework is increasingly recognized. The ongoing implementation of the Water Framework Directive (WFD) could be viewed as a reorganization phase in the process of change in institutional arrangements and ecosystems. In this case study from the Northern Baltic Sea River Basin District, Sweden, we focus in particular on data and information management from a multi-level governance perspective from the local stakeholder to the River Basin level. We apply a document analysis, hydrological mapping, and GIS models to analyze some of the institutional framework created for the implementation of the WFD. The study underlines the importance of institutional arrangements that can handle variability of local situations and trade-offs between solutions and priorities on different hierarchical levels.

Life-support value of ecosystems: a case study of the Baltic Sea Region

Abstract Ecosystems support the economy with necessary environmental goods and services. In the Baltic Sea Region the accumulated pressure from industries, agriculture and fisheries has reduced this support. Water and soil quality has decreased, forests and the quality of commercial fish species have been degraded, and marine top predator populations have diminished. Humans have through predation, pollution and competition replaced the seals as the major top consumers of the Baltic Sea food-web. Our estimates indicate that up to 85% of the total primary production of the Baltic Sea nowadays supports the fish catches. In the Baltic Sea Region the natural capital is increasingly replacing man-made capital as the limiting factor for socio-economic development. In order to attain sustainable development socio-economic activities and their feed-back flows must be adapted to the capacity of the life-supporting ecosystems. The challenge for the future of the whole region is to fit the industrial societies into ecosystem processes and functions. Input management of production systems and ecological engineering are important tools for this purpose.

Enhancing transdisciplinary dialogue in curricula development

A crucial step towards realizing transdisciplinary understanding is to address transdisciplinary issues in university curricula, and to train students in critically analyzing and understanding disciplinary metaphors. We present an experimental exercise at Stockholm University with the aim of finding a constructive way to introduce transdisciplinary elements in disciplinary courses and thus increase student awareness of disciplinary metaphors. The exercise required a minimum of formal university decision procedures and thus circumvented the institutional barriers that tend to obstruct the establishment of full transdisciplinary programs.

Changing Use Patterns, Changing Feedback Links : implications for Reorganization of Coastal Fisheries Management in the Stockholm Archipelago, Sweden

Property rights are important institutions for regulating the use of valuable natural resources from coastal ecosystems. In this case study, we identify and analyze property rights and user pattern ...

Social-ecological feedback links for ecosystem management: a case study of fisheries in the Central Baltic Sea archipelago

In this paper, we address the implications of changing social-ecological feedback links for a sustainable management of coastal regions applying an ecosystem management perspective. This case study ...

Management practices for building adaptive capacity : a case from northern Tanzania

The development of human societies rests on functioning ecosystems. This thesis builds on integrated theories of linked social-ecological systems and complex adaptive systems to increase the understanding of how to strengthen the capacity of ecosystems to generate services that sustain human well-being. In this work, I analyze such capacity in human-dominated production ecosystems in Tanzania and Madagascar, and how this capacity is related to local management practices. Resilience of social-ecological systems refers to the capacity to buffer change, to re-organize following disruption, and for adaptation and learning. In Papers I and II, qualitative interview methods are used for mapping and analyses of management practices in the agroecosystem of the Mbulu highlands, Northern Tanzania. Practices such as soil and water conservation, maintenance of habitats for pollinators and predators of pests, intercropping, and landscape diversification, act to buffer food production in a variable environment and sustain underlying ecological processes. The practices are embedded in a decentralized but nested system of institutions, such as communal land rights and social networks, that can buffer for localized disturbances such as temporary droughts. Paper II compares these findings with practices in a farming system in Sweden, and suggests that similar mechanisms for dealing with uncertainty and change can exist in spite of different biophysical conditions. In Papers III and IV, interviews are combined with GIS tools and vegetation sampling to study characteristics and dynamics of the dry forests of Androy, southern Madagascar. Paper III reports on a previously underestimated capacity of the dry forest of southern Madagascar to regenerate, showing areas of regeneration roughly equal areas of degenerated forest (18 700 ha). The pattern of forest regeneration, degradation, and stable cover during the period 1986-2000 was related to the enforcement of customary property rights (Paper III). Paper IV reports on a network of locally protected forest patches in Androy that is embedded in a landscape managed for agricultural or livestock production and contributes to the generation of ecosystem services and ecosystem resilience at a landscape scale. Forest protection is secured by local taboos that provide a well-functioning and legitimate sanctioning system related to religious beliefs. In Paper V, two spatial modeling tools are used to assess the generation of two services, crop pollination and seed dispersal, by the protected forest patches in southern Androy. The functioning of these services is dependent on the spatial configuration of protected patches in the fragmented landscape and can be highly vulnerable to even small changes in landscape forest cover. In conclusion, many of the identified practices are found to make ecological sense in the context of complex systems and contribute to the resilience of social-ecological systems. The thesis illustrates that the capacity of human-dominated production ecosystems to sustain a flow of desired ecosystem services is strongly associated with local management practices and the governance system that they are embedded in, and that, contrary to what is often assumed, local management can and does add resilience for desired ecosystem services. These findings have substantial policy implications, as insufficient recognition of the dynamics of social-ecological interactions is likely to lead to failure of schemes for human development and biodiversity conservation.

Marine Ecosystem Support to Fisheries and Fish Trade

The relationships between fish production in marine ecosystems and fish processed and traded in the economy is analyzed for Sweden’s foreign trade in herring, cod, salmon and fish meal for 1986. Estimates are made of direct and indirect energy requirements in the marine ecosystem and the economy to produce the traded fish products. A comparison is made of trade balances in economic terms, expressed as export and import prices and in energy terms, expressed in solar energy terms. In monetary terms imports are 2.5 times larger than exports, but in energy terms about 7.3 times larger than exports meaning that Sweden is receiving products and work performed in the marine ecosystems at a lower price than it is selling its own products. This indicates that Sweden is dependent on much larger ecosystem support areas performing necessary work than is reflected in standard economic evaluatioa The importance of considering such ecosystem support in economic decision-making and management of indigenous and foreign living marine resources is emphasized.

The role of horse keeping in transforming peri-urban landscapes: A case study from metropolitan Stockholm, Sweden

ABSTRACT The authors analyze sustainable cultural landscapes through the lens of ecosystem services. Their case study focuses on transformation of the peri-urban landscape of the Stockholm region, Sweden. Peri-urban landscapes are characterized by diversified and fragmented land uses that are strongly related to urban lifestyles. The rapidly increasing trend for recreational horse keeping is replacing traditional agriculture. Horse keepers’ and local government perspectives on horse keeping are examined, as well as the related demand for ecosystem services, which affects the landscape. The article is based on government documents, interviews with local government officials, and field visits to 16 horse-keeping facilities in two municipalities. Horse keeping was found important for sustaining cultural ecosystem services related to a rural cultural landscape and for maintaining traditional agriculture that provides provisioning ecosystem services. However, several differences between traditional agriculture and horse keeping that affect the demand for ecosystem services related to land use were found to shift the focus from provisioning services to recreational services. The authors conclude that horse keeping, as an emerging crosscutting issue in peri-urban landscapes, needs new more integrative planning processes that account for the full range of ecosystem services and links between cultural services and ecosystem functioning.

Patches and pulses as fundamental characteristics for matching ecological and cultural diversity: the Baltic Sea archipelago

Focusing on the Baltic archipelago, we address the questions: to what extent are the rhythms of natural and social systems compatible and under which criteria can we make them coincide? Existing mismatches between resource availability and human demand are identified as well as human attempts to dampen ecosystem fluctuations. By means of examples from forestry and fisheries, we illustrate how changes in property rights and technology have altered the diversity and resilience of the archipelago system. Our results suggest that intermediate scale processes of years up to a century are most critical for bringing natural and cultural systems in concordance. The time frame relevant to management and policy in the archipelago seems to correlate with eutrophication processes and the regrowth of forests. In fisheries, a shift from traditional to recreational fisheries has created fishery patterns badly adapted to the dynamics of the coastal ecosystem in disregard of traditional ecological knowledge. A multipurpose and adaptive management of natural resources is advocated as the most appropriate approach for promoting ecological and cultural diversity in the Baltic archipelago. Existing mismatches between the two have to be addressed by governing institutions at many hierarchical levels.