Study On Compacting Characteristics Of Straw-containing Soil And Its Effect On Root Chracteristics Of Maize

As the rate of agricultural mechanisation continues to increase,the problem of soil compaction caused by agricultural machinery is becoming more and more serious.Soil compaction directly leads to a decrease in soil permeability,an increase in bulk weight,bulk density,compaction and porosity,an increase in resistance to plant root penetration and a corresponding increase in soil strength,which also results in soil degradation and a decrease in the quality of cultivated land.Soil compaction is therefore an important factor in the degradation of the physical properties of soils.In this paper,by building a soil stress detection system,indoor compaction tests were carried out for both soil and straw mixed and mulched conditions,stress changes during compaction were monitored by both sensors and Fuji sensory pressure paper,and finally,by using the soil stress detection system,pot tests were carried out to study the growth of maize under different levels of compaction.The main research elements of this paper are as follows:The main research elements of this thesis are as follows:(1)A soil stress detection system was established to meet the function of monitoring stress during soil compaction and reveal the process mechanism of soil compaction.A test platform is established for the following clay loam soil and wheat straw compaction tests and potting tests.The compaction testing system is designed in blocks for each board,such as the soil compaction mechanical components and the soil stress detection module.The soil pressure transducer is controlled by Lab VIEW software acquisition program and NI c DAQ-9174 data acquisition system to achieve dynamic monitoring of the stress-strain relationship in the soil compaction process by the platform.The displacement transducer is controlled via the Syntron software to meet the soil compaction process with a constant pressure under pressure.(2)Soil compaction tests were carried out with clay loam soils and wheat straw as the research object through the soil stress test platform,with pure clay loam soils as the control group to study the effect of wheat straw content on soil bearing capacity and characteristic parameters under two conditions: mixing wheat straw with clay loam soil ratio and straw covered soil.This indicates that the soil stress value decreases with increasing soil depth for different wheat straw contents in the soil,and decreases with increasing soil depth for the same soil depth.The soil stress decreases with increasing straw content ratio at the same soil depth.(3)Through pot experiments,the lower soil limit was used as a measure of soil compaction to analyse the growth of maize plants at different levels of compaction and the conformation of the root system at different levels of compaction.In this chapter,maize roots were collected and planted under different levels of soil compaction to compare the dry weight of the roots and the degree of development of the main and fibrous roots.The experimental results showed that the root growth was the most developed under the T2 treatment and the most suitable for maize growth.