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R. Fensholt A. Anyamba S. Huber S.R. Proud C.J. Tucker J. Small E. Pak M.O. Rasmussen I. Sandholt C. Shisanya 《International Journal of Applied Earth Observation and Geoinformation》2011
Since 1972, satellite remote sensing of the environment has been dominated by polar-orbiting sensors providing useful data for monitoring the earth's natural resources. However their observation and monitoring capacity are inhibited by daily to monthly looks for any given ground surface which often is obscured by frequent and persistent cloud cover creating large gaps in time series measurements. The launch of the Meteosat Second Generation (MSG) satellite into geostationary orbit has opened new opportunities for land surface monitoring. The Spinning Enhanced Visible and Infrared Imager (SEVIRI) instrument on-board MSG with an imaging capability every 15 min which is substantially greater than any temporal resolution that can be obtained from existing Polar Operational Environmental Satellite (POES) systems currently in use for environmental monitoring. Different areas of the African continent were affected by droughts and floods in 2008 caused by periods of abnormally low and high rainfall, respectively. Based on the effectiveness of monitoring these events from Earth Observation (EO) data the current analyses show that the new generation of geostationary remote sensing data can provide higher temporal resolution cloud-free (<5 days) measurements of the environment as compared to existing POES systems. SEVIRI MSG 5-day continental scale composites will enable rapid assessment of environmental conditions and improved early warning of disasters for the African continent such as flooding or droughts. The high temporal resolution geostationary data will complement existing higher spatial resolution polar-orbiting satellite data for various dynamic environmental and natural resource applications of terrestrial ecosystems. 相似文献
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Recovery of polluted ecosystems: the case for long-term studies 总被引：6，自引：0，他引：6
Hawkins SJ Gibbs PE Pope ND Burt GR Chesman BS Bray S Proud SV Spence SK Southward AJ Langston WJ 《Marine environmental research》2002,54(3-5):215-222
Recovery of marine ecosystems from pollution has tended to receive less attention than the study of new or continuing impacts, but such studies are important in charting recovery from acute incidents and following legislation to deal with chronic contamination. Recovery is inevitably a long-term process, and where such studies have been made they are often too short-lived. Interest quickly wanes following an acute incident and governmental bodies rapidly switch to new legislative priorities for chronic inputs. We review three case studies: recovery of dogwhelk populations after local extinction by tributyl tin leachates from anti-fouling paints; recovery of rocky shore communities from oil spills; and recovery of estuarine ecosystems from industrial and urban development. We then make some generalisations about recovery processes before making a plea for long-term studies of polluted areas. 相似文献
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The occurrence of infections with Trichinella sp. in polar bears (Ursus maritimus) from northeastern Greenland has been studied by examination of muscle samples, mainly diaphragm, from 38 animals shot during the period 1983-1987. Trichinella larvae were demonstrated in 12 bears (32%) with an average of 9.2 larvae/g muscle tissue. No bears younger than three years old were infected. The prevalence of Trichinella among bears of the age group 3-4 years was 25% and 53% among older animals. 相似文献
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