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11.
S.BERA  R.K.GHOSH 《水稻科学》2013,20(4):298-302
The effects of bispyribac sodium 10% SC and butachlor 50% SC on soil physico-chemical properties and microflora in transplanted kharif rice were investigated over two seasons (2010 and 2011).Effects of the herbicide on bulk density,water holding capacity,moisture content,soil pH,organic matter content,electrical conductivity,as well as total nitrogen,available phosphorus and available potassium contents were analyzed along with microflora population (total bacteria,actinomycetes and fungi).No significant changes in soil physico-chemical properties were observed.Herbicide treatments resulted in decreases in microbial counts initially.With the degradation of applied herbicides within a considerable time,the microflora populations even exceeded the initial count at 60 d after application of the herbicide.  相似文献   
12.
As a consequence of land abandonment and marginalization, open areas and traditionally managed wood pastures are disappearing from many alpine valleys. Landscape and stand scale dynamics were analyzed in two neighboring inner valleys of central Italian Alps (Valmalenco, SO) dominated by larch (Larix decidua Mill.) forests and experiencing different historical land use intensities. Land cover mapping obtained from object-oriented analysis of aerial photographs was used to quantify land cover changes between 1961 and 2003. Spatial statistics were used to quantify landscape patterns, and intensive sampling in permanent plots was employed to perform point pattern analysis at the stand scale. Expansion of forested area at the expense of wood pastures was the main land cover transition observed. Differences in land use intensities were responsible for different patterns at the landscape scale: (1) heavier grazing and human pressure created a more diverse and fragmented mosaic of meadows, open woodlands, forests and wood pastures, (2) lower human impact favored a more homogeneous and stable system. A decline in grazing pressure in the late 1970s favored the establishment of larch and spruce in a clustered pattern, typical of the subalpine belt. Subalpine wood pastures, likewise many other semi-natural environments, are in danger of disappearing and lose their productive and cultural characteristics, because they are developing into more closed and dense stands.  相似文献   
13.
Photodegradation of triadimefon has been studied on glass and soil surfaces. A number of photoproducts have been isolated and characterised by NMR, IR and MS. Photolysis resulted in considerable amounts of 1-(4-chlorophenoxymethyl)-1,2,4-triazole, 1-(4-chlorophenoxy)-2,2-dimethyl-1-(1,2,4-triazol-1-yl)propane, 1-(1,2,4-triazol-1-yl)-3,3-dimethylbutan-2-one and 1-(4-chlorophenoxy)-3,3-dimethyl-1-(1,2,4-triazol-1-yl)butan-2-ol. Rates of photodegradation on glass and soil surfaces under UV and sunlight followed first-order kinetics with a significant correlation coefficient. Photodegradation was greater on alluvial soil than on laterite soil.  相似文献   
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