Responses to Projected Changes in Climate and UV-B at the Species Level

Abstract

Environmental manipulation experiments showed that species respond individualistically to each environmental-change variable. The greatest responses of plants were generally to nutrient, particularly nitrogen, addition. Summer warming experiments showed that woody plant responses were dominant and that mosses and lichens became less abundant. Responses to warming were controlled by moisture availability and snow cover. Many invertebrates increased population growth in response to summer warming, as long as desiccation was not induced. CO 2 and UV-B enrichment experiments showed that plant and animal responses were small. However, some microorganisms and species of fungi were sensitive to increased UV-B and some intensive mutagenic actions could, perhaps, lead to unexpected epidemic outbreaks. Tundra soil heating, CO 2 enrichment and amendment with mineral nutrients generally accelerated microbial activity. Algae are likely to dominate cyanobacteria in milder climates. Expected increases in winter freeze-thaw cycles leading to ice-crust formation are likely to severely reduce winter survival rate and disrupt the population dynamics of many terrestrial animals. A deeper snow cover is likely to restrict access to winter pastures by reindeer/caribou and their ability to flee from predators while any earlier onset of the snow-free period is likely to stimulate increased plant growth. Initial species responses to climate change might occur at the sub-species level: an Arctic plant or animal species with high genetic/racial diversity has proved an ability to adapt to different environmental conditions in the past and is likely to do so also in the future. Indigenous knowledge, air photographs, satellite images and monitoring show that changes in the distributions of some species are already occurring: Arctic vegetation is becoming more shrubby and more productive, there have been recent changes in the ranges of caribou, and "new" species of insects and birds previously associated with areas south of the treeline have been recorded. In contrast, almost all Arctic breeding bird species are declining and models predict further quite dramatic reductions of the populations of tundra birds due to warming. Species-climate response surface models predict potential future ranges of current Arctic species that are often markedly reduced and displaced northwards in response to warming. In contrast, invertebrates and microorganisms are very likely to quickly expand their ranges northwards into the Arctic.

Effect of body mass and melanism on heat balance inLiolaemuslizards of thegoetschiclade

“…It has been considered an accelerator for heat gain (e.g. Kettlewell, 1973;Kingsolver and Wiernasz, 1991;Clusella-Trullas et al, 2007;Reguera et al, 2014); however, it also is associated with UV radiation protection (Gunn, 1998;Callaghan et al, 2004;Calbó et al, 2005;Reguera et al, 2014), crypsis (Kettlewell, 1973;Endler, 1984;Reguera et al, 2014) and intra-specific communication or sexual selection (Wiernasz, 1989;Fedorka et al, 2013). Additionally, the advantages of melanism may be associated with local conditions (local adaptation; Castella et al, 2013), as a result of phenotypic plasticity (Alho et al, 2010) or the interaction between predator avoidance and thermoregulation (Lindstedt et al, 2009).…”

Impact of warming on Nostoc colonies (Cyanobacteria) in a wet hummock meadow, Spitsbergen

“…The predicted effects of a doubling of the atmo− spheric CO 2 will be dramatic; mean annual temperatures in the Arctic may be 3-5°C higher within 100 years (Maxwell 1992;ACIA 2004;Callaghan et al 2004a;Callaghan et al 2004b). Most models also predict that the overall annual global precipitation will increase.…”

Effects of ultraviolet-B radiation on crop growth, development, yield and leaf pigment concentration of tartary buckwheat (Fagopyrum tataricum) under field conditions

“…As CFCs with a half-life ranging from 50 to 150 years can remain in the upper atmosphere, decreased ozone levels will not be recovered to the pre-1970s levels until 2050 (UNEP, 2002). During the last few decades, numerous investigations concerning the influence of enhanced UV-B radiation on different plant species have been conducted (Callaghan et al, 2004). The majority of plant species are negatively affected * Corresponding author.…”