Webpages tagged with «climate change»

Published Sep. 11, 2013 5:44 PM

In recent decades, plant species in many mountain areas have expanded their distribution upwards, parallel with a trend of accelerated climate warming in many of these regions. To analyse the extent of floristic change in relation to local climate change over the long term, and to assess the sensitivity of mountain flora to changes in temperature, precipitation, and other potential drivers, a large span of sites and time periods, and a large variation in climate parameters is needed. Previous studies have shown that altitudinal shifts of vegetation are different for plant species found in snowbed communities and species found on ridges. In 1999 Einar Heegaard did a study of species distributions (vascular plants, bryophytes and lichens) from snowbeds to ridges using snowbed-ridge transects at different altitudes from approximately 1200 m above sea level and up to 1550 m. This summer we reanalyzed 21 of these transects. We will use these to study the differentiated altitudinal changes of vegetation of snowbed communities versus changes on the ridge communities.

Published Sep. 6, 2013 3:01 PM

World-wide observations of current climate change, such as increased temperature and severe rain events and droughts are caused by release of CO2 by human activities using fossil fuels and by biogeochemical feed-back mechanisms (Solomon et al. 2007, Wesssel et al. 2004, Melillo et al. 2011). Such changes may disrupt the functioning of terrestrial ecosystems on our planet, which are vulnerable to disturbance (Millennium Ecosystem Assessment 2005, Elmendorf 2012). 

Published Aug. 16, 2013 3:31 PM

An understanding of glacier response to climate change is important for models of sea level change and the planning of hydroelectric schemes. Current models have failed to predict the current rapid melting of the Greenland ice sheets because we understand very little about the subglacial environment. The aim of this project was to investigate the suitability of Midtdalsbreen for the installation of a glacial environmental sensor network to study glacial processes and in particular in situ subglacial processes.

The Glacsweb project would provide technology capable of collecting the data necessary for the careful monitoring and investigation of glacial processes in remote and fragile landscapes. The availability of live data on the web would allow the public to gain an understanding of how climate change is affecting the Arctic.

Published Feb. 7, 2013 7:45 AM

This project is investigating the reproductive response of Carabid beetles to changes in their environment's temperature. Some of these species have adapted to cold climates by slowing down their maturation and changing the timing of their reproduction. We now wish to know if these populations will be able to do the oposite in response to warming temperaters. The results may be used to make predictions about the implications of global warming on future distributions of these insects.

 

Published Feb. 6, 2013 2:19 PM

A climate change experiment with open top chambers (OTCs) was established in the Dryas octopetala heath on Sanddalsnuten in 2000. Combined warming and nutrient addition has increased productivity and grass dominance at the cost of mosses, lichens, and small herbs, resulting in decreased diversity. In a seed sowing experiment we examined the relative role of dispersal and local interactions for alpine plant community diversity under climate warming. The long term effects of warming and local interactions on species recruitment and community dynamics will be examined in the coming years. This project is part of the International Tundra Experiment (ITEX).

Published Feb. 6, 2013 1:51 PM

Dividing available resources between reproduction and different somatic processes in organisms is associated to trade-offs in each species life-history. The variability in cost responses in plants has been discussed upon the variability in environmental conditions. We established a field experiment at Sanddalsnuten with the alpine herb, Parnassia palustris L. in focus. The reproductive level was artificially manipulated to determine if there exists cost of reproduction in this species. The field experiments involved manipulations of temperature regime by using open top chambers (OTCs) to simulate a warmer climate, and manipulations of current level of reproductive investment by supplemental hand-pollination (increasing output) and bud removal (decreasing output). Growth, survival, and reproduction was then determined the next year and compared inside and outside the OTCs.

 

Published Feb. 6, 2013 1:39 PM

In ecology, although there is a demand for it, there are very few long time series. So, after finishing the fieldwork for my master thesis in 1995, I decided to keep 90 of the Geranium sylvaticum L. individuals and continue to follow them up on a yearly basis, looking at between year variations as well as long-term trends. Every summer since 1995 I have measured; investments in reproduction (number of flowers, number of fruits, fruit:flower ratio, number of seeds) and vegetative growth (number of stalks and the height, number of leaves).

Published Feb. 6, 2013 11:02 AM

The project focuses on the effects of snow for the distribution of mountain plants, vegetation types, species richness, and plant phenology. So far 350 permanent plots (2x2m) have been established, south, east and north of Hardangervidda (60 in the Finse area). Floristic composition and soil samples have been analysed in all plots. In most of the plots, data-loggers are recording soil temperatures. From April until late summer, plots are regularly visited in order to measure snow thickness and study plant phenology. The results of the studies will also be used a basis for evaluation of possible ecological effects of global warming.

Published Feb. 4, 2013 12:31 PM

A climate change experiment with open top chambers (OTCs) was established in the Dryas octopetala heath on Sanddalsnuten in 2000. Combined warming and nutrient addition has increased productivity and grass dominance at the cost of mosses, lichens, and small herbs, resulting in decreased diversity. In a seed sowing experiment we examined the relative role of dispersal and local interactions for alpine plant community diversity under climate warming. The long term effects of warming and local interactions on species recruitment and community dynamics will be examined in the coming years. This project is part of the International Tundra Experiment (ITEX).

Published Feb. 4, 2013 12:31 PM

Dividing available resources between reproduction and different somatic processes in organisms is associated to trade-offs in each species life-history. The variability in cost responses in plants has been discussed upon the variability in environmental conditions. We established a field experiment at Sanddalsnuten with the alpine herb, Parnassia palustris L. in focus. The reproductive level was artificially manipulated to determine if there exists cost of reproduction in this species. The field experiments involved manipulations of temperature regime by using open top chambers (OTCs) to simulate a warmer climate, and manipulations of current level of reproductive investment by supplemental hand-pollination (increasing output) and bud removal (decreasing output). Growth, survival, and reproduction was then determined the next year and compared inside and outside the OTCs.

Published Feb. 4, 2013 12:31 PM

In ecology, although there is a demand for it, there are very few long time series. So, after finishing the fieldwork for my master thesis in 1995, I decided to keep 90 of the Geranium sylvaticum L. individuals and continue to follow them up on a yearly basis, looking at between year variations as well as long-term trends. Every summer since 1995 I have measured; investments in reproduction (number of flowers, number of fruits, fruit:flower ratio, number of seeds) and vegetative growth (number of stalks and the height, number of leaves).