You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Can High Arctic Soil Microarthropods Survive Eleveated Summer Temperatures?
I. D. Hodkinson, S. J. Coulson, N. R. Webb and W. Block
Vol. 10, No. 3 (Jun., 1996), pp. 314-321
Published by: British Ecological Society
Stable URL: http://www.jstor.org/stable/2390278
Page Count: 8
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
1. Tolerance of high summer temperatures was investigated in seven common species of oribatid mite (Acarina) and springtail (Collembola) found in soils associated with dominant vegetation types in West Spitsbergen, Svalbard. 2. Laboratory survival experiments are linked with field data from a 3-year temperature manipulation experiment to characterize the response of these animals to elevated field temperatures. 3. A 1-h exposure to 30⚬C under moist conditions showed that none of the species studied suffered significant mortality. The temperature required to kill all individuals was between 35-40 and 40-45⚬C for springtails and mites respectively. Under dry conditions at equivalent temperatures, differences in survival between mites and Collembola were strongly accentuated. Oribatid mites were little affected by the additional drought stress but the lethal temperature for springtails was shifted downwards by several degrees. 4. In parallel 3-h exposure experiments under moist conditions, the thermal death point was shifted downwards by c. 2.5⚬C in all the species, compared with 1-h exposures. Under dry conditions most Collembola died but mite survival differed little from that in the corresponding wet treatment over 3 h. 5. In longer-term experiments some mature Onychiurus arcticus survived more than 196 and 68 days at 5 and 25⚬C respectively. Above 30⚬C individuals survived for <24 h. 6. Regression relationships were established between maximum microhabitat temperatures and screen temperatures over 3 years. These were used to predict past maximum vegetation/litter mat and soil temperatures from historical screen data and to estimate the screen temperatures necessary to raise microhabitat temperatures to the thermal death point of the soil-dwelling arthropods. 7. The results are used to interpret the findings of a 3-year field experiment which examined the response of mite and springtail populations to temperature enhancement on two tundra sites, using small polythene tents. 8. High Arctic soil microarthropods appear able to cope with the higher summer temperatures they may experience as a result of climate change. It is the associated changes in soil moisture status that will probably produce the more significant changes in the microarthropod community. Species differ in their susceptibilities, but a decrease in soil moisture appears to favour oribatid mites at the expense of Collembola.
Functional Ecology © 1996 British Ecological Society