Soil solarization moisture

Numerical and experimental studies. Soil Sci 131 82-87 Mahrer Y, Naot O, Rawaitz E, Katan J (1984) Temperature and moisture regimes in soils mulched with transparent polethylene. Soil Sci Soc Am J 48 362-367 Malathrakis NE, Loulakis MD (1989) Effectiveness of the type of polyethylene sheet on soil solarization. Acta Hort (ISHS) 255 235-242... 

The time of year in which a pesticide is applied significantly affects its dissipation rate due to temperature, moisture, and solar-irradiance effects on abiotic and biotic dissipation processes. For example, dissipation rates for agrochemical applications made in the springtime are normally greater than those observed for fall (autumn) applications. Thus, the timing of agrochemical applications made in field soil dissipation studies should closely match those occurring under acmal-use conditions. 

The rainfall regime in arid areas is characterized by low, irregular and unpredictable precipitation, often concentrated in a few rainstorms, creating humid conditions in the soil for a short period and over a limited area. In many arid areas, several years may elapse between successive rainfalls. The moisture supplied to the soil from rain is offset by evaporation, that is related to air temperature, air humidity and intensity of solar radiation. Because of the irregular rainfall distribution, mean precipitation values have little meaning, if not also the range of variation is indicated. 

Effects of solarization were found related to a combination of many parameters, though most authors agreed that soil temperature and moisture, climate and weather, and type and properties of mulching film are key factors for solarization results (Katan et al. 1987 Stapleton and DeVay 1995). 

Plant productivity is determined by factors such as plant species composition, moisture, soil fertility, growing season length, and solar radiation—many of which are affected by human activities. All else equal, increases in primary productivity and production of plant tissues will lead to increases in soil C stock, while decreases will lead to decreases in soil C stock. The rate of change in soil C stock is determined by the difference between C inputs and outputs, as well as the turnover times of the soil C, which are often not known. Here we review briefly how some environmental factors are expected to alter productivity and explore how the effects on stock depend on the number of soil carbon pools and their turnover times. 

The temperature dependent algorithms used to predict natural sulfur emissions do not account for all of the variation in observed emissions. Other important environmental parameters may include, but are not limited to, tidal flushing, availability of sulfur, soil moisture, soil pH, mineral composition, ground cover, and solar radiation. A more accurate estimation of the national sulfur inventory will require a better understanding of the factors which influence natural emissions and the means to extrapolate any additional parameters which are determined to be important. 

Increased UV dose can occur as a result decreased cloudiness. For example, the number of sunny days in Central America has increased significantly over the past decade [77]. Such changes in weather patterns were found to significantly correlate with the loss of amphibian species. Although clear sky irradiance would not likely vary greatly from day to day, aside from changes associated with solar angle, the cumulative UV dose would increase considerably compared to doses that occur under cloudy conditions. In addition, temperature and soil moisture would likely decline under such conditions. Individually and in combination, these stressors could be harmful and contribute to population decline. 

The rapid and wide-ranging fluctuations in environmental conditions such as temperature, solar radiation, humidity, and soil moisture can significantly influence the chemical composition of the leaf. An increase in day/ night temperature combinations is generally correlated with total alkaloid levels, presumably as a result of increased synthesis and translocation of nicotine in response to increased root metabolism and transpiration (Long and Woltz 1977). Total alkaloid levels were highest in the lower leaves at... 

For a given urea distribution, the faster the urea hydrolysis, the higher the ammoniacal and carbonate concentrations can become. The ammonia/ammonium equilibrium (pKa = 9.3) at the soil surface determines how much ammonia is lost to the atmosphere, but the loss is also related to soil moisture, wind turbulence across the soil, soil CEC, and possibly solar energy input, In addition to producing high pH conditions conducive to ammonia volatilization losses from surface-applied urea,... 

On the basis of the soil potential (fertility of the main soil types), the peculiar features of the climate conditions which are determined by the interaction of such factors as incoming solar radiation, atmospheric circulation, moisture supply, the researchers of the Institute of bioenergy crops and sugar beets of the NAAS of Ukraine defined a beetroot zone-the most favorable zone (as to its soil and climatic conditions) for sugar beet cultivation [5],... 

The aboveground characteristics of the cover crops influenced solar penetration and thus mean soil temperature and moisture. For a quick survey at noon on June 8, 1996 we found a > 85% reduction in blue (400-600 nm) and red (600-700 nm) solar radiation at the soil surface underneath approximately 930 g/m of standing or cut wheat shoot residues (Blum et al. 2002). The solar radiation at the soil surface of the reference plots on that day was 190 6 p W/cm /nm. 

If a real world problan is sought that is inherently messy, where mathematical functions are difficult to apply, uncertainty modeling processes wonld be an excellent example. Engineering processes, at or near the land surface depend on topography, vegetation, and soil moisture, rainfall patterns and intensity, potential evapo-transpiration, air tanperatures, solar radiation, winds, and dew points. Each of the variables changes either in space or in time, and many change in both space and time. Nonetheless, it is necessary to calculate such processes in this real world... 

There are over 200 identified bacterial genera and a single soil sample may have over 4,000 genetically distinct bacteria [28]. The greatest population is located in the topsoil, a few millimetres below surface, since conditions of temperature, moisture, aeration, and food are more favourable. The solar radiation reduces the distribution of bacteria on the surface. Deeper in the soil the bacteria are then controlled by the nntrient availability, water content, pH, O2 and CO2 content, and temperature. 

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