Microbial degradation moisture effect

Temperature and moisture are two of the most important environmental variables that affect microbial growth, survival, and activity. At optimal temperature and moisture conditions, chemical and enzymatic reactions in the cell will occur the most rapidly and growth and activity will be the highest. However, below and above these optimal conditions, microbial activity decreases. The microbial degradation of. v-triazines appears to follow the same pattern. The effect of soil moisture and temperature on the degradation of terbutryn was evaluated by Chu-Huang et al. (1975). They reported that after 20 weeks of incubation above 10°C and at 14% soil moisture, phytotoxic levels of terbutryn to wheat were not detected in Teller sandy loam soil. 

Density and flexural modulus, 205 Density, 53, 54, 57, 59, 63, 69-71, 73,105, 124, 134, 137, 146, 147, 154, 202-223, 258, 384, 414, 500, 567, 569, 571 Buckling, effect on, 209 calculations, 217 commercial deck boards, 215 cross-sectional, 212, 213 distribution, 212, 213 hollow board, 212, 213 flexural modulus, correlation with, 205 microbial contamination, effect on, 210 microbial degradation, effect on, 210 moisture content, effect of, 209 panels of hollow boards, 212, 213 ribs of hollow boards, 212, 213... 

Microbial contaminants will usually need to be able to attack ingredients of a medicine and create substrates necessary for biosynthesis and energy production before they can replicate to levels where obvious spoilage becomes apparent since, for example, 10 microbes will have an overall degradative effect around 10 time faster than one cell. However, growth and attack may well be localized in surface moisture films or very unevenly distributed within the bulk of viscous formulations such as creams. Early... 

The PHOSter II system is only applicable to contaminants that can be biologically degraded. In addition, it is only effective in settings where microbial activity is phosphorus limited. At sites with high contaminant concentrations, product recovery may be required during the initial treatment stage. Hydraulic conductivity and moisture content also determine the effectiveness of the PHOSter II technology. 

The soil is a complex structure with close interrelationship among factors that influence biodegradation of pesticides, such as the structure of the pesticide, presence of an effective, active microbial community capable of degradation, and bioavailability of the compound in space and time (sorption, moisture content, temperature, nutrients, and soil pH) to enzymes or to whole cells (Aislabie and Lloydjones, 1995). 

Since the phenoxyalkanoic acid herbicides are degraded in the soil by biological processes, factors that affect microbial activity will directly affect their breakdown. Soil pH, soil type, soil organic matter, herbicide formulation, and herbicide concentration can all influence the rate of microbial decomposition ( 4, 5). Greater effects are experienced with moisture and temperature, since these factors have a profound influence on microbial activity and thus on herbicide breakdown (4 5). It has been concluded ( 5), that soil temperature above 10°C and moistures above the wilting point are necessary for biological degradation of phenoxyalkanoic acids. 

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