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251.
The increasing global demand for food production, often causing excessive use of chemical fertilizers, has led to the deterioration of soil health. Immediate action is required to restore soil health in a sustainable manner. This review advocates switching to use of organic matter(manure and compost) that contains vital nutrients for plant growth and helps restore soil health. Humic substances(HSs), derived from degraded plant remains and found ubiquitously in nature,are an important source of o... 相似文献
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Toxicity in three dogs from accidental oral administration of a topical endectocide containing moxidectin and imidacloprid 总被引:1,自引:1,他引:0
Three dogs were presented with a history of oral administration of a topical endectocide containing imidacloprid and moxidectin. They were diagnosed with imidacloprid and moxidectin intoxication, having ingested doses ranging from 7.5 to 1.4 mg/kg of imidacloprid and 1.9 to 2.8 mg/kg of moxidectin. The three dogs were affected to different degrees of severity, but all displayed signs of ataxia, generalised muscle tremors, paresis, hypersalivation and disorientation. Temporary blindness occurred in two cases. The three dogs were tested for the presence of the multi-drug resistance 1 gene deletion, which can cause an increased sensitivity to the toxic effects of moxidectin, and were found to be negative. Treatment included gastrointestinal decontamination, intravenous fluid therapy and benzodiazepines to control muscle tremors. All three dogs made a complete recovery within 48 h of ingestion. 相似文献
255.
A 4-year-old Siberian Husky dog was treated with brown snake antivenom by his regular veterinarian after a witnessed episode of brown snake envenomation. The dog was discharged 5 hours post presentation despite an ongoing coagulopathy. The dog was presented to the emergency centre 2 hours later because the owner believed the dog to be in pain. Initial examination revealed an ambulatory but neurologically normal patient with thoracolumbar pain and laboratory evidence of a coagulopathy. Despite correction of the coagulopathy, the signs progressed to bilateral hind limb paresis after approximately 3 hours of hospitalisation, and continued to deteriorate over the next 56 hours to loss of deep pain perception in the right hind limb. Computed tomography imaging identified the presence of an extradural haematoma which was subsequently removed via a hemilaminectomy. Surgical decompression was successful in treating the spinal compression and the dog recovered with minimal complications. To our knowledge this is the first report of extradural haematoma secondary to coagulopathy induced by brown snake envenomation. 相似文献
256.
Distribution of thiobacillus ferrooxidans and leptospirillum ferrooxidans: implications for generation of acid mine drainage 总被引:1,自引:0,他引:1
MO Schrenk KJ Edwards RM Goodman RJ Hamers JF Banfield 《Science (New York, N.Y.)》1998,279(5356):1519-1522
Although Thiobacillus ferrooxidans and Leptospirillum ferrooxidans are widely considered to be the microorganisms that control the rate of generation of acid mine drainage, little is known about their natural distribution and abundance. Fluorescence in situ hybridization studies showed that at Iron Mountain, California, T. ferrooxidans occurs in peripheral slime-based communities (at pH over 1.3 and temperature under 30 degreesC) but not in important subsurface acid-forming environments (pH 0.3 to 0.7, temperature 30 degrees to 50 degreesC). Leptospirillum ferrooxidans is abundant in slimes and as a planktonic organism in environments with lower pH. Thiobacillus ferrooxidans affects the precipitation of ferric iron solids but plays a limited role in acid generation, and neither species controls direct catalysis at low pH at this site. 相似文献
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J. M. AL‐Awadhi 《Land Degradation \u0026amp; Development》2013,24(1):2-11
Soil degradation and vegetation deterioration in contrasting areas (open desert versus protected desert) in the northeastern part of Kuwait were investigated, using field measurements, and laboratory methodologies. The average infiltration rate of compacted soils studied was found to be 52 per cent lower than that of the undisturbed soils we investigated. The bulk density of the compacted soils was 19 per cent higher than that of the non‐compacted soils. The average topsoil resistance of severely compacted soils was 13 per cent greater than that of undisturbed soils and is mainly due to overgrazing, and off‐road vehicle use. We found that the overall vegetation cover status of open areas investigated was approximately 70 per cent less than for the protected areas studied. As a consequence of soil compaction and vegetation deterioration, sand deflation processes, and sand movement prevail in open areas. The total average percentages of course grain sizes in unprotected soils and heavily disturbed soils by vehicles (off‐road) are 51 and 103 per cent greater, respectively. The annual rate of sand transport during the last 20 years, from the prevailing wind direction (NW) in the area has increased by 81 per cent. The delicate balance between soil and natural vegetation cover is easily disturbed by off‐road vehicle use associated with overgrazing and recreation activity. A restoration plan is needed in order to reduce land degradation and to allow natural vegetation recovery. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献