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11.
Anne C. Arsenault Peter M. Foley Noel P. Clancey 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(6):589
A 12-year-old neutered male American Staffordshire terrier dog was referred to the Atlantic Veterinary College, Prince Edward Island, Canada, for suspected immune-mediated hemolytic anemia. Babesiosis (Babesia vulpes) was confirmed using polymerase chain reaction testing. The dog was successfully treated with a 10-day protocol of atovaquone/proguanil (TEVA Pharmaceutical Industries, Toronto, Ontario), 13.5 mg/kg BW, PO, q8h and azithromycin (Pharmascience, Montreal, Quebec), 10 mg/kg BW, PO, q24h. To the authors’ knowledge, this report is the first documented case of babesiosis caused by Babesia vulpes in a dog from Canada. 相似文献
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A GIS-based plant prediction model for wetland ecosystems 总被引:5,自引:0,他引:5
An existing non-spatial model for the prediction of response of wetland plant species on ecological factors has been transformed into a GIS-based prediction model which produces spatial output at the landscape scale. The input, spatial patterns of the ecological factors, were constructed with geostatistical spatial interpolation (kriging). With this GIS-based model the spatial patterns of presence and absence of 78 wetland plant species are predicted for an area with wetlands in the Netherlands of approximately 500 square kilometers. The GIS-based model has been validated, and the estimated uncertainty of the input has been propagated through the model. At the species level the output shows spatially coherent and non-random patterns. The validation is affected by the propagation of input errors through the model. The number of valid predictions declines approximately 10–20% when 95% confidence intervals are used in the validation. This study shows that it is feasible to use a geostatistical interpolation method to construct spatial patterns of ecological factors on a landscape scale and to use these patterns as input for a GIS-based prediction model. The added uncertainty on the input values however, affects the number of valid predictions of the model. 相似文献
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Peter M. Groffman James M. Tiedje Delbert L. Mokma Stephen Simkins 《Landscape Ecology》1992,7(1):45-53
Large scale analyses of biogeochemical processes are necessary for understanding anthropogenic effects on global climate and
environmental quality. Regional scale estimates of denitrification from forest soils in southern lower Michigan USA were produced
by stratifying the region into landscape experimental units using soil texture and natural drainage classes, and extrapolating
data to larger areas using a geographic information system (GIS). Previous landscape-scale research established relationships
between soil texture and drainage and denitrification and quantified annual denitrification N loss in nine soil texture/drainage
groups. All forest soils within the region (64 series) were assigned to one of these nine groups based on their texture and
drainage characteristics and were assigned an annual denitrification N loss value. A regional estimate of denitrification
was produced by multiplying the areal extent of each of the nine soil groups by their annual denitrification N loss value.
Loam-textured soils underlie 47% of the regional forest and accounted for 73% of the forest denitrification. Sandy soils were
found under 44% of the regional forest but produced only 5% of the regional denitrification. Clay loam soils underlie 9% of
the regional forest and produced 22% of the denitrification. Annual denitrification N loss for the region was estimated as
1.4×107 kg N/yr. We used denitrification enzyme activity (DEA) as a proxy for annual denitrification N loss to determine if the relationship
between denitrification and soil texture and natural drainage that we observed at the landscape scale held up at the regional
scale. DEA was measured in 22 soils across the region and was strongly related to soil texture and natural drainage (r2=0.61), suggesting that extrapolation of data from the landscape to the regional scale was justified. 相似文献
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Huimin Yang Murray Unkovich Ann McNeill Xianzhi Wang 《Biology and Fertility of Soils》2011,47(4):377-385
Symbiotic N2 fixation by lucerne (Medicago sativa) has capacity to provide significant inputs of N to agro-ecosystems, and the species has also been shown to scavenge soil
mineral N and thus act as a sink for excess reactive N. The balance between these two N cycle processes was investigated in
an extensive irrigated lucerne growing region where nitrate contamination of groundwater has been reported. We sampled 18
permanent pure lucerne stands under irrigation for standing dry matter, total shoot N, and N2 fixation using 15N natural abundance along with activity of the inducible enzyme nitrate reductase as indicators of use of soil NO3− by lucerne. On average 65% of lucerne N was obtained from symbiotic N2 fixation. Converting standing dry matter estimates to annual N2 fixation amounts we calculated average N2 fixation of 311 kg N/ha, including N in roots and nodules. Uptake of N from soil by lucerne was calculated to be 181 kg N/ha/year.
We were not able to identify the source of this soil mineral N, although nitrate reductase activity of lucerne was higher
than that of non-N2 fixing species examined. 相似文献
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