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51.
52.
Zhao Dawei T. Larssen Zhang Dongbao Gao Shidong R.D. Vogt H.M. Seip O.J. Lund 《Water, air, and soil pollution》2001,130(1-4):1733-1738
Chongqing is among the heaviest polluted cities in China. Combustion of coal with relatively high sulfur content causes high sulfur emission and deposition in the area. Effects on soils and waters of the acid deposition in the Chongqing area have been studied in the field at a forested site outside the city. Deposition chemistry and fluxes, soil and soil water chemistry as well as surface water chemistry are presented for the period 1996–1998. There are some stress symptoms at the forest in the area and severe forest damage has been reported at Nanshan, closer to Chongqing center. Monitoring of the acidification situation in the area must be followed closely as impacts may be expected if the deposition is not reduced in the future. The deposition of sulfur, H+ as well as calcium at the site is high. Wet deposition of sulfur is estimated to 4.7 – 5.7 g S m?2 yr?1 during the three years sampled; dry deposition is probably of similar size. Annual volume-weighted pH in bulk deposition was 4.0 – 4.2 and the calcium wet deposition flux was 2.6 – 3.6 g Ca2+ m?2. There are considerable seasonal variations in the concentrations, related to the seasonal variations in precipitation amount (dry winter, wet summer). The soils at the site are acid with median base saturation of 12% and 8% in the topsoil and subsoil, respectively. In soil water, aluminum concentrations are typically in the range 3–8 mg L?1. However, due to the high base cation deposition, the Al/(Ca2++Mg2+) molar ratio is below unity in most samples, indicating little damage of forest due to aluminum in soil water. 相似文献
53.
Candolfi M. Bigler F. Campbell P. Heimbach U. Schmuck R. Angeli G. Bakker F. Brown K. Carli G. Dinter A. Forti D. Forster R. Gathmann A. Hassan S. Mead-Briggs M. Melandri M. Neumann P. Pasqualini E. Powell W. Reboulet J. -N. Romijn K. Sechser B. Thieme Th. Ufer A. Vergnet Ch. Vogt H. 《Anzeiger für Sch?dlingskunde》2000,73(6):141-147
This paper is a guidance document for side-effect testing with plant protection products on non-target arthropods under semi-field
and field conditions. The principles, methods, endpoints and interpretation of non-target arthropod semi-field and field trials
which should be conducted for registration of plant protection products in the European Union are presented and discussed.
The recommendations presented reflect the opinions of the experts from authority, academia, industry and consulting which
participated at the IOBC (International Organisation of Biological Control), BART (Beneficial Arthropod Regulatory Testing)
group and EPPO (European Plant Protection Organisation) Joint Initiative workshop held in Versailles (France) on the 25–26
October, 1999. 相似文献
54.
Lee JC Bruck DJ Dreves AJ Ioriatti C Vogt H Baufeld P 《Pest management science》2011,67(11):1349-1351
In August 2008, the first detection of the spotted wing drosophila, Drosophila suzukii, to the North America mainland in California caused great concern, as the fly was found infesting a variety of commercial fruits. Subsequent detections followed in Oregon, Washington, Florida and British Columbia in 2009; in Utah, North Carolina, South Carolina, Michigan, and Louisiana in 2010; and in Virginia, Montana, Wisconsin, Pennsylvania, New Jersey, Maryland and Mexico in 2011. In Europe, it has been detected in Italy and Spain in 2009 and in France in 2010. Economic costs to the grower from D. suzukii include the increased cost of production (increased labor and materials for chemical inputs, monitoring and other management tools) and crop loss. An effective response to the invasion of D. suzukii requires proper taxonomic identification at the initial phase, understanding basic biology and phenology, developing management tools, transferring information and technology quickly to user groups, and evaluating the impact of the research and extension program on an economic, social, and environmental level. As D. suzukii continues to expand its range, steps must be initiated in each new region to educate and inform the public as well as formulate management tactics suitable for the crops and growing conditions in each. 相似文献
55.
56.
Craighead Kimberly Yacelga Milton Wan Ho Yi Vogt Robert Cushman Samuel A. 《Landscape Ecology》2022,37(1):129-146
Landscape Ecology - Few habitat modeling studies consider multiple spatial or temporal scales; less identify the operative scale of an organism's response to predictor variables. Optimizing... 相似文献
57.
58.
MT McCulloch AW Tudhope TM Esat GE Mortimer J Chappell B Pillans AR Chivas A Omura 《Science (New York, N.Y.)》1999,283(5399):202-204
Uplifted coral terraces at Huon Peninsula, Papua New Guinea, preserve a record of sea level, sea-surface temperature, and salinity from the penultimate deglaciation. Remnants have been found of a shallow-water reef that formed during a pause, similar to the Younger Dryas, in the penultimate deglaciation at 130,000 +/- 2000 years ago, when sea level was 60 to 80 meters lower than it is today. Porites coral, which grew during this period, has oxygen isotopic values and strontium/calcium ratios that indicate that sea-surface temperatures were much cooler (22 degrees +/- 2 degreesC) than either Last Interglacial or present-day tropical temperatures (29 degrees +/- 1 degreesC). These observations provide further evidence for a major cooling of the equatorial western Pacific followed by an extremely rapid rise in sea level during the latter stages of Termination II. 相似文献
59.
Stalder HP Meier P Pfaffen G Wageck-Canal C Rüfenacht J Schaller P Bachofen C Marti S Vogt HR Peterhans E 《Preventive veterinary medicine》2005,72(1-2):37-41; discussion 215-9
We have genetically analyzed ruminant pestiviruses. All >150 bovine viral diarrhea (BVD) viruses isolated from cattle in Switzerland belonged to genotype 1, with subgenogroups e, h, k and b found in decreasing frequency. To date, representatives of subgenogroup k have been detected in Switzerland only. Despite serological evidence of Border disease in sheep, only few Border disease viruses have been isolated, all of which belong to the novel group 3. Serological evidence suggested that pestivirus infections may occur also in wild ruminants in Switzerland but no isolates are available for analysis. In addition, we describe two pestiviruses, one a cell culture contaminant and the other isolated from a buffalo, that cluster with a recently proposed novel pestivirus species. 相似文献
60.
A Gonzalez JH Lawton FS Gilbert TM Blackburn I Evans-Freke 《Science (New York, N.Y.)》1998,281(5385):2045-2047
The experimental fragmentation of landscapes of a natural ecosystem resulted in declines in the abundance and distribution of most species in the multispecies animal community inhabiting the landscapes and the extinction of many species. These declines caused the deterioration of the positive interspecific relation between local population abundance and distributional extent in this community. However, when patches were connected by habitat corridors, an immigration "rescue effect" arrested declines in both abundance and distribution and maintained the observed positive relation between them. These results demonstrate the importance of metapopulation dynamics and landscape connectivity for the persistence of populations in fragmented landscapes. 相似文献