"The significance of landscape patterns and connectivity for the resilience of ecosystems and the management of seagrass meadows"
Johan Eklöf (project leader)
Summary of results from Stockholm University.
Email: johane@ecology.su.se
A large proportion of humanity live, or move to, coastal zones. This means that our dependence on ecosystem services such as fishing or clean water free from algal blooms is on the increase, as well as our own impact on the ecosystems, which may disrupt the natural balance among species and cause a sudden radical change – a shift - in an ecosystem in which certain species disappear and others take over. One factor which probably affects such shifts is the spatial scale of the disturbances. Surrounding individuals often have a positive but spatially limited effect on recovery in disturbed areas through seed dissemination or predation. Because of this, species and ecosystems recover more slowly from large than from small disturbances. There is also competition from other species for space.
In this study, an investigation was made of the way these factors affect the recovery capacity of underwater meadows of seagrass in shallow sea bottoms. By creating "nurseries" for many economically important fish species and preventing coastal erosion, these seagrass meadows are one of the most valuable coastal ecosystems which we have. Unfortunately, their extent has greatly diminished owing to human disturbances such as eutrophication, dredging and the discharge of environmentally harmful compounds.
The results are important for the management of coastal regions. If we want to protect seagrass or induce it to spread, we should perhaps focus not only on seagrass but also on geese and sandworms. If the overriding objective is to get the seagrass meadows to recover to historical levels, it will perhaps be necessary to limit grazing by geese, which may be considered to be a far too controversial measure, since we also want to protect the goose population.
"Landscape ecology of organic farming: Biodiversity, weed evolution, biological control and farmer participation"
Jan Bengtsson (project leader)
Summary of results with list of publications from Crop Production Ecology, SLU.
Email: Jan.Bengtsson@ekol.slu.se
The objective of this research theme was integrate knowledge of ecological processes at major scales in order to evaluate and develop methods for the preservation of biodiversity and to improve biological control in organic farming. Four doctoral theses and more than 30 scientific articles and chapters in books have been produced in this project.
The study shows that organic farming usually results in increased biodiversity and improved control, but that the response to an improved cropping system varies between groups of organisms and also between different landscapes. This makes it difficult to develop general support systems without taking account of specific conditions. The results also show that there is a coupling between the attitude of farmers to nature and the biodiversity on their farms.
"The cultivation and fodder values of narrow-leafed lupin – a comparison with peas"
Ullalena Boström (project leader)
Summary of results from SLU.
Email: Ullalena.Boström@vpe.slu.se
Lupins can replace soya
Early maturing cultivars of narrow-leafed lupin can be grown also in Northern Europe. Lupin seed can replace soya as the source of protein for cattle, pigs, poultry and fish, but lupin has low resistance to weeds. It would therefore be valuable if the top part of the plant or immature seeds could be harvested and, after preservation, become feed.
The aim of the study was to investigate the conditions for growing lupin in Sweden and to demonstrate alternative harvesting methods. Compared with peas, lupin seeds have a higher content of protein and lipids. However, the protein appears to have a lower rumen degradability. One important difference also is that lupin contains almost no starch, while the high starch content of peas may limit the quantity that can be used.
"Insect resistance and life history evolution in wild and feral Brassicas: integrating key processes in population establishment and persistence"
Tina DHertefeldt (project leader)
Summary of results with list of publications from Lund University
Email: tina.dhertefeldt@ekol.lu.se
Owing to climate changes, the need to produce biofuel and an increasing population, future crops must be tolerant and have a higher yield. It is expected that greater productivity and greater resistance will give the plants a competitive advantage. With regard to genetically modified crops, the advantages due to the new traits must also be considered in relation to possible risks.
Rape is the dominant oilseed crop in Sweden, but too have a good yield, pollen beetles must be controlled. This has so far been done using insecticides containing pyrethroids. During the past decade, however, resistant pollen beetles have appeared in the Nordic countries and new ways are now sought to control these. The results of the project indicate that there are several possible ways for gene flow from genetically modified rape in the Swedish farming landscape.
Field experiments with increased protection against insect herbivores showed that the wild relative field mustard doubled its seed production and that more seed plants were established in squares that had been sprayed with insecticide, but there were differences between regions. A small number of volunteers of genetically modified rape were found a long time after the experiment had ended, and highlight the importance of ongoing evaluation of soil preparation methods in order to reduce the risk that the rape seed will enter the seed bank.
"Assortative mating and speciation among host plant races and pheromone strains of the European corn borer Ostrinia nubilalis - a genomic approach"
Christer Löfstedt
Summary of results with list of publications from Lund University
Email: christer.lofstedt@ekol.lu.se
Speciation and species extinction are processes with dramatic consequences for biodiversity. Despite extensive theorisation, the empirical material for different speciation scenarios is often very poor.
The European corn borer is a significant insect pest in agriculture and horticulture. The spread of the species is seen as a direct consequence of anthropologically caused climate changes. The species makes use of several host plants and is polymorphic with regard to sex pheromones. It is possible that we are witnessing ongoing speciation, where variation in the communication system and host plants may give rise to new moth species. At the same time, the species may serve as a model system for the development of new methods for pest control with the help of pheromones.
So far, studies have only shown that the pheromone glands of the female moths can give rise to new mating signals. In order to fully understand how the communication system changes during the speciation process, we must now make corrresponding studies of the detection by males of the pheromones which, in the ultimate, contribute to speciation in insects.
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