Skip to main content
Advanced Search

Filters: Contacts: Turkington, Roy (X)

71 results (70ms)   

View Results as: JSON ATOM CSV
1.?Ecosystem properties may be determined by the number of different species or groups of species in a community, the identity of those groups, and their relative abundance. The mass ratio theory predicts that the effect of species or groups of species on ecosystem properties will be dependent on their proportional abundance in a community. 2.?Single plant functional groups (graminoids, legumes, non-leguminous forbs) were removed from a natural grassland in northern Canada to examine the role of group identity in determining both ecosystem properties and biomass compensation by remaining species. Removals were conducted across two different environmental treatments (fertilization and fungicide) to examine the context...
Chapter 5
Categories: Publication; Types: Citation; Tags: M1-Ecosystems
The combustion of fossil fuels and associated warmer temperatures are causing a global increase in the availability of soil nutrients such as nitrogen. This will have pronounced effects on plants at northern latitudes that are adapted to low nutrient conditions. An experiment in northern Canada set up in 1990 has investigated the effects of long-term nutrient enrichment (fertilizer addition) and mammalian herbivore exclusion (fencing) on an understory plant community. We used this experiment to assess how 22 years of fertilization has affected investment in sexual reproduction in four herbaceous understory species. We measured reproductive output at the plot level (proportion of plants flowering) for four species...
Categories: Publication; Types: Citation; Tags: M1-Ecosystems
Global levels of reactive nitrogen are predicted to rise in the coming decades as a result of increased deposition from the burning of fossil fuels and the large-scale conversion of nitrogen into a useable form for agriculture. Many plant communities respond strongly to increases in soil nitrogen, particularly in northern ecosystems where nitrogen levels are naturally very low. An experiment in northern Canada that was initiated in 1990 has been investigating the effects of long-term nutrient enrichment (fertilizer added annually) on a boreal forest understory community. We used this experiment to investigate why some species increase in abundance under nutrient enrichment whereas others decline. We focused on four...
Our research on the herbaceous understory vegetation in the Kluane region, Yukon, has focused on the structure and function of natural forest understory and grassland communities. The research has involved two long-term projects. The first investigated fertilizer addition and mammalian herbivore exclosure in understory vegetation over a 20-year period and showed that nutrient availability, and not herbivory, controlled herbaceous biomass. Fertilization increased the amount and nutrient content of vegetation, but 13 species were lost, whereas natural levels of mammalian herbivory rarely affected this vegetation or its diversity. The second study investigated how removing plant functional groups from a grassland influences...
Global levels of reactive nitrogen are predicted to rise in the coming decades as a result of increased deposition from the burning of fossil fuels and the large-scale conversion of nitrogen into a useable form for agriculture. Many plant communities respond strongly to increases in soil nitrogen, particularly in northern ecosystems where nitrogen levels are naturally very low. An experiment in northern Canada that was initiated in 1990 has been investigating the effects of long-term nutrient enrichment (fertilizer added annually) on a boreal forest understory community. We used this experiment to investigate why some species increase in abundance under nutrient enrichment whereas others decline. We focused on four...
Categories: Publication; Types: Citation; Tags: M1-Ecosystems


map background search result map search result map Voles Are Attracted to Fertilizer in Field Experiments The effects of fertilization and herbivory on the herbaceous vegetation of the boreal forest in north-western Canada: a 10-year study The Effects of Fertilization and Herbivory on the Phenology of the Understory Vegetation of the Bored Forest in Northwestern Canada Density dependence in an experimental boreal forest understory community Facilitation in an unproductive boreal forest understorey community The effects of fertilization and herbivory on the herbaceous vegetation of the boreal forest in north-western Canada: a 10-year study Density dependence in an experimental boreal forest understory community Voles Are Attracted to Fertilizer in Field Experiments Facilitation in an unproductive boreal forest understorey community The Effects of Fertilization and Herbivory on the Phenology of the Understory Vegetation of the Bored Forest in Northwestern Canada