Ecosystem services of biodiversity in organic grasslands

The use of multi-species mixtures in herbage production can add value in terms of improved conditions for pollinating insects, better resource utilization, carbon sequestration, yield stability, animal health and product quality. This is the hypothesis of a new project - EcoServe - where the goal is to design grasslands, which increase both the nature value and provide an economically sustainable food production

Hayfields – Floral resources and pollinators

Pollinating insect populations are generally declining at local, national and global scales, and several wild pollinator species are extinct or endangered. •Almost half of the Danish bumblebee species are on the red list. •Such declines present a critical threat to future agricultural production, but biodiversity of pollinating insects and insect-pollinated plants is also at risk. •Organic grasslands with a high proportion of herbs may provide a significant better habitat for pollinating insects, and in particular, well-managed hayfields with species flowering during the entire growing season

Pollination. Presentation of selected projects. Integrated management of Natural Capital: Biodiversity and Ecosystem Services

Pollination is vital to the maintenance both of wild plant communities and agro-ecosystems. Beside the well-known, domesticated honey bee, pollinators include e.g. hover flies, butterflies, bumblebees and solitary bees. Pollinators have declined along with the intensification of agriculture. Aarhus University investigates cause – effect relations involved in the decline of pollinators in order to assess the relative importance of different aspects of agricultural practice and land use. For instance, we investigate response patterns of wild pollinators to pesticides and develop indicators that quantify pesticide effects on flowering plants. Important challenges include interactions between man-made effects and environmental drivers such as climate change

Økologiske græsmarker som fødekilde for bestøvende insekter

Produktionsgræsmarker som en del af sædskiftet leverer kvalitetsfoder, men biodiversiteten i disse marker er lav. Typisk findes der ud over hvid- og rødkløver kun to-tre andre urter i markerne. I projektet EcoServe (http://agrsci.au.dk/forskning/faciliteter/httpwwwokoplatformdk/planter/ecoserve/ ) undersøger vi om iblanding af flere urter i græsmarkerne øger funktionaliteten. Projektet er rettet imod økologisk produktion, men vil også være relevant for konventionelle landmænd

Effects of cutting regime, surroundings and field age on floral resources for pollinators in hay fields

Bees and other flower-visiting insects are experiencing periods of food shortage, particularly in intensively managed agricultural landscapes in Europe. As part of the Danish project EcoServe (http://agro.au.dk/ecoserve/) we therefore investigated whether increased richness of selected herbaceous species in organic hay fields acted as a floral resource thus enhancing abundance and biodiversity of pollinators. Moreover, we investigated if availability of floral resources was affected by cutting regime (timing and number of cuttings during the growing season) in 11 herbaceous species, which are often used in grassland seed mixtures. In a field survey, we visited 20 organic hay meadows of different age (3-100 years), and conducted surveys regularly throughout the flowering season to quantify diversity of insect-pollinated plants and pollinators. Our results showed that diversity of pollinators was significantly and positively related to diversity of plants, but that hay fields embedded in a complex landscape harbored a higher diversity of both plants and insects than hay fields in more homogeneous areas. Also, diversity of plants and insects increased in older hay meadows. In an experimental set-up, we tested the availability of flowers in plots of monocultures and a mixture of 11 herbaceous species under two cutting regimes: (1) plots were cut once every four weeks throughout the growing season, and (2) plots were cut only at the end of the flowering season. While the majority of species provided flowers for pollinators when plots were not cut during the flowering season, most plant species set few if any flowers if cut frequently. One exception was Trifolium repens, which was slightly stimulated by cutting. Thus, traditional grasslands which are frequently mowed are expected to be poor in flowers. Our results suggest that it is important to leave unmowed flower-rich areas in the fields throughout the flowering season to avoid periods of food shortage. The potential for unmowed hay fields to enhance diversity and abundance of pollinators, however, depend on the composition of the surrounding landscape and age of the field

Education and second birth rates in Denmark 1981-1994

A high educational attainment is shown to have a positive effect on second birth rates for Danish one-child mothers during the period 1981-94. We examine whether a time-squeeze is a possible explanation: due to the longer enrolment in the educational system, highly educated women have less time at their disposal in order to get the desired number of children. Also, we examine to what extent the partner's education can explain some of the positive effect. We find no evidence that the positive effect of education is due to either a time-squeeze nor to a partner effect.birth rate, Denmark, education, fertility, partner effect, time-squeeze

Økologiske græsmarker som fødekilde for bier og andre bestøvere

Bier og andre blomsterbesøgende insekter mangler i dag føde gennem dele af året, specielt i intensivt drevne landbrugsområder. Som en del af projektet EcoServe undersøger vi derfor i hvilket omfang økologiske græsmarker, ved iblanding af udvalgte urter, kan bidrage som fødekilde og dermed til øget antal og diversitet af bestøvere

Biodiversitet i græsmarken - en fordel for både natur og fødevareproduktion

Anvendelse af mange-arts-blandinger i græsmarker til produktion kan øge nytteværdien, f.eks. i form af forbedrede vilkår for bestøvende insekter, øget ressourceudnyttelse, kulstoflagring, udbyttestabilitet, husdyrsundhed og produktkvalitet. Det er hypotesen i et nyt projekt, hvor målet er at designe græsmarker, som både øger naturværdien og giver en økonomisk bæredygtig fødevareproduktion

Mangfoldighed i den økologiske græsmark

Anvendelse af mange-arts-blandinger i græsmarker til produktion kan øge nytteværdien i form af forbedrede vilkår for bestøvende insekter, øget ressourceudnyttelse, kulstoflagring, udbyttestabilitet, husdyrsundhed og produktkvalitet. Det er hypotesen i et nyt projekt – EcoServe - hvor målet er at designe græsmarker, som både øger naturværdien og giver en økonomisk bæredygtig fødevareproduktion