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Background and aims – Agricultural intensification and loss of farmland heterogeneity have contributed to population declines of wild bees and other pollinators, which may have caused subsequent declines in insect-pollinated wild plants. Material and methods – Using data from 37 studies on 22 pollinator-dependent wild plant species across Europe, we investigated whether flower visitation and seed set of insect-pollinated plants decline with an increasing proportion of arable land within 1 km. Key results – Seed set increased with increasing flower visitation by bees, most of which were wild bees, but not with increasing flower visitation by other insects. Increasing proportion of arable land had a strongly variable effect on seed set and flower visitation by bees across studies. Conclusion – Factors such as landscape configuration, local habitat quality, and temporally changing resource availability (e.g. due to mass-flowering crops or honey bee hives) could have modified the effect of arable land on pollination. While our results highlight that the persistence of wild bees is crucial to maintain plant diversity, we also show that pollen limitation due to declining bee populations in homogenized agricultural landscapes is not a universal driver causing parallel losses of bees and insect-pollinated plants.

Large volumes of excavated soil and rock are generated in building- and construction projects. These materials need to be transported longer and longer distances due to the densifications of cities. The transportation affects the environment in terms of noise and emissions, but also makes high demands on road infrastructure. To reduce the transport distances an increased responsibility for the excavated rock generated needs to be taken. Responsibility can be increased through an introduction of means of control. Previous studies describe public procurement as an effective tool to increase the responsibility taken by public authorities. Public procurement is regulated by law but the inclusive of environmental requirements is optional, which makes procurement as a tool flexible. The aim of this thesis is to examine public procurement as a tool to control and reduce the environmental impacts from handling, and specifically transporting excavated rock generated in municipal construction projects. The study consists of a case study conducted in Södertörns eight municipalities and a wider analysis that has been carried out in the regions of Stockholm, Västra Götaland and Skåne. The two studies showed that municipal officials generally do not believe that the handling of excavated rock is a municipal responsibility, it lies in the entrepreneurs self-interest to implement regional mass balances. Entrepreneurs instead, consider it to be a municipal problem that can be resolved only when the municipality begins to take responsibility for the excavated rock generated, by example through developing regional plans. As in previous studies, the result indicates that the supplier and purchaser consider the environmental requirements in the procurement process differently. The thesis identify four different factors, which limits the municipalities ability and willingness to take more responsibility in the procurement process regarding the matter excavated rock from construction. The, OptiMass

Naturbetesmarker är en av de mest artrika naturtyperna i Sverige men har under de senaste hundra åren blivit allt färre och mer fragmenterade i det svenska landskapet. För att motivera markägare att öppna upp igenväxta och övergivna marker delas det ut bidrag varje år för att markerna skall restaureras och bete eller slåtter skall återinföras. Vilken långvarig effekt restaureringen har på naturbetesmarkens artdiversitet är bristfälligt utvärderad och dokumenterad. Jag har undersökt hur reproduktionen hos två vanliga gräsmarksarter, gökärt (Lathyrus linifolius) och gullviva (Primula veris), påverkas beroende på om betesmarken är eller har varit övergiven. Frön från tre olika markkategorier samlades in; kontinuerligt betade, övergivna och restaurerade. Jag testade tre hypoteser: 1.Reproduktionen hos gullviva och gökärt är högst i kontinuerligt betade marker och lägst i övergivna, igenväxta, marker. 2.Bland de restaurerade markerna ökar frösättningen med tid sedan restaurering. 3.Landskapsvariabler (proportion betesmark, åkermark, lövskog inom en och fem kilometer samt avstånd till närmsta betesmark) har påverkan på arternas frösättning. Hög andel betesmark i omgivande landskap och kort avstånd till närmsta betesmark har positiv påverkan på frösättningen medan hög andel åkermark och lövskog har negativ påverkan. För att testa ovanstående hypoteser undersöktes även om arternas marktäckningsgrad, betesmarkens storlek och andelen fröherbivorer i gökärtens baljor har påverkan på frösättningen. Två olika statistiska analyser användes för att hitta signifikanta samband; regressionsanalys och ANOVA-analys. Slutsatserna som drogs utifrån de statistiska analyserna är följande: 1.ANOVA-analysen visade att de undersökta arternas reproduktion inte skiljer sig mellan markkategorierna, vilket tyder på att en mark som varit övergiven i 10-50 år troligen inte har varit utan hävd tillräckligt länge för att pollinatörerna skall börja minska i förekomst. Därmed kan ingen negativ effekt p, Semi natural grasslands are one of Sweden’s most species-rich habitats but during the last hundred years they have become fewer and more fragmented in the Swedish countryside. Annually grants are distributed in order to motivate landowners to open up abandoned and overgrown pastures and begin grazing and mowing them again. The lasting effects of restoration on the species diversity of semi-natural pastures are poorly evaluated and documented. I have examined how the reproductive rate of two common grassland species, bitter vetch (Lathyrus linifolius) and cowslip (Primula veris) are affected depending on whether the pasture is, or has been abandoned. Seeds were collected from three different categories of pastures; continuously grazed, abandoned and restored. I tested three hypotheses: 1.The reproduction of cowslip and bitter vetch is highest in continuously grazed pastures, and lowest in abandoned, overgrown ones. 2.Among restored pastures, seeding increases with the time elapsed since restoration. 3.Landscape variables (proportion of pasture, cropland and deciduous forest within one and five kilometers and the distance to the closest grassland) have impact on the seeding of the studied species. Large proportions of pastures and short distance to closest grassland have a positive effect on the seeding of the species and large proportions of cropland and deciduous forest have a negative effect. To test the hypotheses, the species ground coverage, pasture size and the proportions of seed herbivores were investigated. Two statistical tests were used to find significant correlations: regression analysis and ANOVA analysis. The conclusions that could be drawn from the statistical analyses were the following: 1.The ANOVA-analysis revealed that the reproduction of the studied species did not differ between the different categories of pastures. This suggests that a grassland which has been abandoned for 10-50 years, has not yet been abandoned so long that the pollinators sh