the highest rate of seedlings emergence、plant height and total dry substance weight of maize of suitable soil moisture in sowing was 19%-22% in loam soil,was 26%-29% in clay soil,but was 13%-15% in sand soil.
The backgrounds of Ti、Mo、Ni and Se had also evident difference. The contents of B and Co were highest in the yellow soil, Ca、Mn、Zn and Ni were highest in the acidic-purple soil,Al、Sb and Se were in the umber soil, the others were highest in the clay soil.
From the test and analysis, it concludes that the boundary friction force has great influence to clay soil displacement and some measures should be taken to reduce friction force during centrifuge test.
Through analysis of SEM of clayey soil of Yun County of China, a conclusion is drawn that the microstructure of clayey soil is fractal, and the relationship between the fractal dimension and the microstructure of clay soil is invertigated.
In consideration of the fact that the clay soil with high moisture content is hard to be crushed and compacted and is low in strength,and the fact that its moisture content decreases slowly when it is used for expressway embankment construction,the mechanical properties of the lime-stabilized over-wet soil as well as its construction technology are studied through the field construction test and laboratory mechanical test.
Measurement of the fractal dimension of crack patterns using box counting indicated that the values of fractal dimension of the clay soil samples increased with the increase of temperature,and a larger value of fractal dimension indicated a more irregular and complex cracks structure.
___TAGSTART___BR___TAGEND___Three fields of marine clay soil were fumigated with 150 l/ha 1,3-dichloropropene (DD) (Telone IITM, Shell 95TM).
___TAGSTART___BR___TAGEND___Several populations of Paratylenchus arculatus from sandy soil and root samples from olive nurseries in southern Spain and from uncultivated clay soil in New South Wales, Australia are described.
Clay soil typification by diffusion and osmotic permeability
Four rice cultivars were used to study the effects of nitrogen fertilizer on nitrogen use efficiency, yield and characteristics of nitrogen uptake under two soil conditions (sandy and clay soil) in soil culture pool.
First, yield of rice in sandy and clay soil was increased by nitrogen application, and that in clay soil was higher than that in sandy soil, but the effect of nitrogen on yield increment was greater in sandy soil than in clay soil.