Soil solarization factors

The cover design and construction should optimize soil conditions for water use by plants. This is an important tool and can be used to ensure success of the ET cover. Plant growth and water use are controlled by soil and air temperature, precipitation, solar radiation, wind, humidity, disease, and insect attack. Neither design nor construction practice can exert significant control over these factors but they can be considered during design to assure success. 

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). 

Rubin B, Benjamin J (1984) Solar heating of the soil involvement of environmental factors in the weed control process. Weed Sci 32 138-142... 

Other factors do intervene. Significant solar heating of the soil surface, so that the soil becomes warmer than the air, causes vertical thermal convection currents to develop within the boundary layers. This introduces turbulence or instability that acts to move the chemical signature up into the free air. When the molecules are moved into the free flow of the air, the effect is to reduce the concentration by dilution. Conversely, when the soil surface is cooler than the air, thermal convection is inhibited, with the result that the molecules are effectively trapped in the boundary layer. This effect is strengthened by the cooling of the air adjacent to the surface, which increases its viscosity. Higher viscosity lowers the Reynold s number, thus decreasing boundary layer thickness. 

Phytoremediation is only effective at shallow depths because root density decreases with depth. The mobility of contaminants also decreases with depth. In addition, phytoremediation is a slower process than some alternative technologies, and cleanup often requires several growing seasons. Environmental factors, including soil type, water availability, temperature, nutrients, and solar radiation can also limit the success of phytoremediation. 

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. 

The importance of the soil in the biosphere lies not only in the production of plants as a source of foodstuffs and certain raw materials for industry it also affects the composition of the atmosphere and of surface and groundwaters, accumulates solar radiation energy and makes possible the circulation of nutrients. It is thus a critical factor governing whether or not a given terrain can support life. 

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],... 

Because the period of pesticide stability in water and soil depends on many different factors (e.g., variations in pH of water and soil, bacterial content, plant and animal content, temperature, humidity, and degree of solar radiation), this classification is largely conventional. It does, however, permit the definition of many organochlorine pesticides (DDT, hexachlorocycyclohexane, aldrin, diel-drin, heptachlor and others) as very persistent (Table 1). 

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