Ann-Mari Jansson

Resilience in natural and socioeconomic systems

We, as a society, find ourselves confronted with a spectrum of potentially catastrophic and irreversible environmental problems, for which conventional approaches will not suffice in providing solutions. These problems are characterized, above all, by their unpredictability. This means that surprise is to be expected, and that sudden qualitative shifts in dynamics present serious problems for management. In general, it is difficult to detect strong signals of change early enough to motivate effective solutions, or even to develop scientific consensus on a time scale rapid enough to allow effective solution. Furthermore, such signals, even when detected, are likely to be displaced in space or sector from the source, so that the motivation for action is small. Conventional market mechanisms thus will be inadequate to address these challenges.

Coping With Uncertainty: A Call for a New Science-Policy Forum

Abstract The scientific and policy worlds have different goals, which can lead to different standards for what constitutes “proof” of a change or phenomena, and different approaches for characterizing and conveying uncertainty and risk. These differences can compromise effective communication among scientists, policymakers, and the public, and constrain the types of socially compelling questions scientists are willing to address. In this paper, we review a set of approaches for dealing with uncertainty, and illustrate some of the errors that arise when science and policy fail to coordinate correctly. We offer a set of recommendations, including restructuring of science curricula and establishment of science-policy forums populated by leaders in both arenas, and specifically constituted to address problems of uncertainty.

QUANTITATIVE SURVEY OF HARD BOTTOM COMMUNITIES IN A BALTIC ARCHIPELAGO

ABSTRACT With the aim of modelling the hard bottom communities of the Asko area in the northern Baltic proper, a stratified random sampling program was designed to quantify the macroscopic fauna and flora of the system over an area of 160 km2. Sampling was made along 32 randomly selected transects. Composition, density and vertical extension of the vegetation belts were mapped and characterized by SCUBA divers. Sampling frames were placed at random along the marked line in a stratified manner, ensuring that at least 1-2 quantitative samples were obtained from each defined belt. By relating the collected data to physical features such as exposure, depth and bottom type, it was possible to calculate the abundance and dry weight biomass distribution of the main macroflora and macrofauna components for the inner and outer parts of the investigation area. Maximum plant biomass, 610 g · m-2, was found at a depth of 1-2 m in the inner area. In the outer area a maximum of 383 g · m-2 was reached at 3-4.5 m depth. Fucus vesiculosus constituted 33% of the plant biomass. The zone of annual filamentous algae ( Pilayella littoralis , Ceramium tenuicorne , Cladophora glomerata etc.) situated above the Fucus belt had an average biomass of 78 g · m-2. Below the Fucus vegetation the plant biomass was dominated by the red algae Furcellaria fastigiata , Phyllophora truncata and Rhodomela confervoides . Maximum animal biomass, ca 490 g · m-2, was found in the 3-4.5 m depth zone. Mytilus edulis was the most important species constituting 90% of the animal biomass (incl. shells). The total figures for standing crops and standing stocks of the investigated area amount to 2163 tons of plants and 8618 tons of animals. Using available data from the area and from literature for turnover times and production of different species, estimates of the total production of the hard bottom communities are presented.

The food-web of theCladophora-belt fauna

KurzfassungIn der Ostsee bildet die GrünalgeCladophora glomerata große, gürtelförmige bestände in Ufernähe. Diese Bestände und ihre Fauna sind für die ökologischen Verhältnisse in der Ostsee von großer Bedeutung. Es wurde daher das Artengefüge dieser Fauna analysiert und Trockengewichtsbestimmungen anC. glomerata durchgeführt. Die Produktivität dieser Alge beträgt 3105 m Algenfilamente pro Quadratdezimeter pro Monat (mittleres Trockengewicht eines 1000 mm langen Algenfilamentes: 0,25 mg). Pro Quadratdezimeter Felsenoberfläche ergeben sich folgende Werte für die Hauptorganismengruppen: Trockengewicht fürCladophora: 0,78 g, für Diatomeen: 1,25 g; Anzahl Tiere: 12 544 Individuen. In Laboratoriumsexperimenten konnte nachgewiesen werden, daß epiphytische Diatomeen derCladophora für die ersten postmarsupialen Stadien des IsopodenIdotea baltica lebensnotwendig und für den GastropodenHydrobia ulvae sowie für Chironomidenlarven zur Erzielung maximaler Wachstumsraten erforderlich sind. Der tägliche Konsum anCladophora-Filamenten wurde für jungeIdotea baltica undGammarus oceanicus an Hand der ausgeschiedenen Faeces ermittelt. Die Nahrungskette innerhalb der Fauna derCladophora-Zone wird an Hand von Beispielen illustriert.Summary1. The species composition of the fauna in theCladophora glomerata belts of the Baltic sea has been studied quantitatively.2. Examples are presented to illustrate composition and density of the epiphytic diatom flora.3. The dry weight ofCladophora glomerata was determined with the aid of length measurements under a microscope. It amounts to 0.25 mg per 1000 mm length of alga filaments, and to 15.9 mg for a tuft with a total surface area of 1 dm2.4. The productivity ofCladophora glomerata was calculated. It amounts to 3105 m alga filaments per dm2 per month.5. The following biomasses per dm2 rock surface have been estimated:Cladophora (dry weight): 0.78 g, diatoms (dry weight): 1.15 g, animals (number of individuals): 12 544.6. The fauna of theCladophora-belt has been subdivided according to feeding types.7. Some herbivores have been studied in laboratory experiments. The epiphytic diatoms are important for survival of the first postmarsupial stages of the isopodIdotea baltica as well as for maximum growth rates of the gastropodHydrobia ulvae and chironomid larvae.8. The daily consumption ofCladophora-filaments has been determined for juveniles of the isopodIdotea baltica and the amphipodGammarus oceanicus by microscope examinations of faecal pellets.9. The diatom diet of the rotiferProales reinhardti has been listed according to genera or species. Among the animals living in theCladophora-belt,P. reinhardti attains the highest numbers of individuals.10. Examples of food-chains within theCladophora community are presented.

Strengths and limitations of localizing food production as a sustainability-building strategy -- an analysis of bread production on the island of Gotland, Sweden

Abstract In this paper we analyze the environmental consequences of local small-scale versus centralized large-scale bread production and the potential for self-sufficiency in bread in a Swedish island community. Mills and bakeries located on the island of Gotland in the Baltic Sea were compared with large-scale production systems on the Swedish mainland. The results show that bread production in local bakeries requires more total energy input per kilogram of bread than the industrial bakery, mainly due to inefficient technology. On the other hand, the analysis shows that emissions of CO 2 , SO 2 and NO x are smaller from bread produced in the small local bakeries than from big bakeries on the Swedish mainland. This is because the transportation routes are much shorter for bread from the small bakeries and because oil is more frequently used for heating the ovens in large and medium sized bakeries. The present local production of flour on Gotland does not satisfy the local demand, but there is a potential for increased self-sufficiency. Farms on the island produce large amounts of bread grain, but only a small fraction (2%) is used in local flour production, while the rest is exported or used as animal fodder. Thus the region has a large potential to produce enough flour for its local population and thus to become less dependent on imports. However, using more locally produced bread grain to produce flour in local mills, improving energy efficiency in small-scale mills and bakeries, changing consumer behavior and internalizing environmental costs of transportation are crucial measures in achieving this goal.

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.

Total energy analysis of Gotland's agriculture: A northern temperate zone case study

Abstract This paper presents a study of a modern agricultural system in a northern region, namely, the island of Gotland, Sweden. Primary emphasis is placed on the energy costs of agriculture and the energy flow within the system. In addition, some attempt is made at assessing environmental costs of declining water quality. For the purpose of perspective some comparisons are made to Israeli agriculture and selected crops in the United States and Great Britain. Historical analysis of Gotlands agriculture indicated the energy provided by horses to be 1 10 in 1972 as compared to 1945 while the fuel consumption of tractors increased 50% from 1954 to 1974. The energy value of the harvest increased ca. 1.5 to 2 times its value in 1947. Direct energy costs include 223 TJ of fuels and 51.9 TJ of electricity. Indirect energy costs include 103 TJ for goods and services, 327 TJ for capital, 465 TJ for the production of fertilizer, 17.6 TJ for the production and transport of grain and 71.2 TJ for the energy cost of feed. The final output of animal and vegetable matter was 1670 TJ. One unit of food energy output required 0.84 units of direct and indirect energy in oil equivalents. Calculations indicate that Gotlands agriculture is more energy costly than selected U.S. crops but at least half as costly as Israeli agriculture. Expressed in energy terms, each year 3240 PJ of renewable solar energy on Gotlands agroecosystem is coupled with 1.3 PJ of fuel and electrical energy to produce 1.7 PJ of edible animal and vegetable products.

Energy flow analysis as a tool for developing a sustainable society—a case study of a Swedish island

Abstract In order to develop a sustainable society, tools are needed to analyze the relationships between human activities and ecosystems and to estimate the carrying capacity of the natural resource base. In this paper, energy analysis is applied in a study of the small island society Namdo in the Stockholm archipelago, Sweden. Namdo has a permanent population of 41 persons and ca. 1000 summer residents. We estimated the energy and material flows on the island, including the primary and secondary production in natural and cultivated ecosystems, human production and consumption of food, and production of waste. Our results show that the island societys consumption exceeds the natural carrying capacity of the island. A great deal of food and energy is imported while only a minor amount of local resources are utilized. The island society is, at present, not constrained by the local resource base, but instead depends heavily on functioning transport communications with the mainland. Based on our findings we make recommendations for greater self-sufficiency, including use of locally available renewable resources and increased recycling.

Food Production, Population Growth, and Environmental Security

There are two broad criteria by which one can judge humanitys success in feeding itself: (i) the proportion of people whose access to basic nutritional requirements is secure; and (ii) the extent to which global food production is sustainable. Even though the two are related, they have usually been discussed separately in popular writings. This has had unfortunate consequences. Writings on (ii) have often encouraged readers to adopt an all-or-nothing position (viz. the future will be either rosy or catastrophic), and this has drawn attention away from the economic misery that is endemic in large parts of the world today. On the other hand, writings on (i) have frequently yielded no more than the catechism that the nearly 1 billion people in poor countries who go to bed hungry each night do so because they are extremely poor. In short, if (ii) has focused on aggregate food production and its prospects for the future, (i) in contrast has isolated food-distribution failure as a cause of world hunger. In this article we will adopt the view that (i) and (ii) should not be studied separately, that their link can be understood if attention is paid to the dynamic interactions between ecological and economic systems operating primarily at the geographically localised level.

A coastal ecosystem fisheries minimodel for the island of Gotland, Sweden

Abstract An aggregated dynamic systems model is formulated to represent the average conditions of coastal waters off the Island of Gotland, Sweden, in the Baltic Sea. Five state variables are used, including a primary producer-grazer component, populations of herring, cod and seals, and storage of available nutrient. Seasonally varying sunlight and temperature, nitrogen runoff fom land, and human fishing activity are modelled as external to the system. Most interactions are assumed to be a (nonlinear) product of the donor and the recipient. The standard output of the model is found to be consistent with measured values over time. The following perturbations are made: pulsing the fishing effort; exclusion of one fish species; increasing the seal population; altering inputs of nitrogen. The model as a whole is quite responsive to both internal and external changes. Regeneration of nitrogen from fish is found to be critical. Nitrogen inflow from runoff is less significant but leads to higher yields of fish when increased. An increase in fish stocks is also achieved by a pulsed rather than continuous harvesting strategy. Increasing the seal population to pre-20th century levels is beyond the systems present carrying capacity.