There is considerable evidence that the growth and elongation of
plant roots increases linearly or almost linearly with increasing water
contents or decreasing moisture-tension of soil. If this is true it is
difficult to distinguish the effects of different water contents on absorption
phenomena such as water or ion uptake...
The influence of soil moisture stress and soil temperature on
transpiration has never been determined explicitly. This relationship
has been neglected mainly because of the lack of a satisfactory method
to control soil moisture stress.
A technique was developed to evaluate this relationship by
controlling soil moisture stress with osmotic...
Petroleum mulch applied on the soil surface over a row of
planted seeds promotes a more rapid and a more uniform germination
of seeds, enhances elongation of seedlings and in some cases increases
the yield of the crop. The beneficial effects of petroleum
mulch have usually been attributed to increased...
A number of investigators have proposed equations to predict
the permeability of porous media. Most of their equations are based
on the distributions of the sizes of the various contributing pores in
the medium. Presently the pore size distributions of agricultural
soils are most commonly obtained from soil water release...
The effect of soil water suction and soil temperature on rates
of transpiration, photosynthesis, respiration and nitrogen fixation of
soybean (Glycine max. Merrill, var. Chippewa 64) seedlings was
studied. A special apparatus was developed in which the soil water
suction of several cells with soybeans growing in them could be...
Temperature and water potential effects on the growth,
transpiration, total nonstructural carbohydrate (TNC) content, and
nutrient uptake of sudangrass (Sorghum vulgare var. piper) were
investigated in laboratory experiments. The effect of nitrogen supply
on the growth and nutrient uptake at constant soil water potential was
also investigated in this study....
One of many important physical properties that must be known
to understand transport phenomena in soils is pore size distribution.
Presently the pore size distributions of soils are most commonly
obtained from soil water characteristic curves. The soil water characteristic
curves are usually obtained by the pressure plate technique.
It...
In regions where soil temperatures limit plant growth, artificial
soil warming may be an economically feasible practice. This hypothesis
was evaluated in a soil warming experiment near Corvallis, Oregon.
This experiment was prompted by the observation that multiple
use of waste heat discharged in the condenser cooling water of thermal...
Experiments were conducted to study the effect of pore size
distribution on the diffusion of 2, 4-Dichlorophenoxyacetic acid (carbon-
14) through water saturated porous media. Eight size fractions of
glass beads were used representing the porous media. It was found
that as the average particle radius, and hence pore radius,...
The effect of soil temperature and plant water stress on nitrogen
uptake, growth rate and transpiration rate of wheat (Triticum aestivum
VILL. , Host) seedlings was studied. A special apparatus for the control
of plant water stress and root temperature was used.
Leaf area was measured by the air flow...