Analysis Of Factors In Cinnamon Topsoil Structure And The Research On The Measures Of Tillage And Fertilizing

Currently, topsoil organic matter content is not high in western Liaoning Province, poorly structured; Farmland soil has long-term to rotary, widespread topsoil becomes shallow, subsoil becomes thicken and thicken, the soil became more compact, and the ability of water storage and conservation was low, seriously restricted the food production in the region.Although qualitative relationship between soil physical and chemical properties and crop yield has been very clear, however,the study on the quantitative relationship between the suitable physical-chemical properties and crop growth in the cinnamon soil area is very lack. Firstly, through the investigation of physical and chemical characteristics index field in cinnamon soil in western of Liaoning Province,determined the impact factor of corn yield,then we put cinnamon soil as the research object, through the plot experiment further study the improvement effect of different tillage measures and different cultivation fertilizer measure to cinnamon soil structure,the research results have important theoretical significance on the construction of a reasonable structure about cinnamon soil of Liaoxi area,conclusions are as follows:1.Different yield cornfield in farming areas survey found that:(1)The yield of>600kg corn field, about 80% fields,the thickness of topsoil and subsoil was 18.5-21.5cm and 9～11 cm; while the corn field of<600kg,about 80% fields,the thickness of topsoil and subsoil was 13～18cm and 14～17cm.(2)Soil compaction in different yield maize was great different,in 10-20cm soil layer, the soil compaction of high yield field decreased by 56% than in low yield soil,and in 20～40cm soil layer,the soil compaction decreased by 42%. The total root of high yield corn was significantly higher than that of low yield field in 0～40cm soil layer, And root distribution ratio of the soil layer in 20～40cm was higher than that of the low yield field.(3)The yield of>600kg corn field, about 80% field,bulk density of topsoil and subsoil was 1.32～1.47g/cm3 and 1.41～1.48 g/cm3; the total porosity was 49%～51% and 46%～48%, and aeration porosity was 13%～16%and 9%～11%;when the yield below 600kg,about 80% fields,the bulk density was 1.37～1.43g/cm3 and 1.49～1.53g/cm3; the total porosity was 46%～49% and 42%～44%,and aeration porosity was 10%～13%and 7%～10%.(4)80% of the yield, more than 600kg corn field plots of soil organic matter content in about 15.7～18.6g/kg;available nitrogen, phosphorus, potassium content are in 35～47mg/kg,19～30 mg/kg and 166～201 mg/kg,and with the per mu yield less than 600kg cornfield,80%of the plots of topsoil organic matter content is only 10～13g/kg,available nitrogen, phosphorus, potassium content respectively for 26-32 mg/kg,9-17mg/kg and 143～160mg/kg.(5)Thickness of topsoil, organic matter content, compaction and aeration porosity and the content of available phosphorus were the major limiting factors for high yield of corn in the cinnamon soil area of Liaoning.Yield with cultivated thickness, organic matter, available phosphorus, aeration porosity is positive correlation (n=60, P＜0.01), but the soil compaction and bulk density is significantly negative correlation (n=60, P<0.01). The degree of correlation was topsoil thickness>organic matter>available phosphorus>soil compaction>aeration porosity.2. By 3 years of different tillage (rotary 15cm, plowing 20cm+rotary tillage, subsoiling 30cm+rotary tillage),studying the influence on the structure of tilth soil, the results showed:(1)Subsoiling+rotary tillage significantly decreased soil compaction of 10-30cm subsoiling and rotary tillage can make the topsoil thickness at 25cm, and the thickness of subsoil kept 8cm; subsoiling+rotary tillage and plowing+rotary tillage could make the topsoil bulk density maintain at 1.34g/cm3 and 1.32g/cm3, and subsoiling rotary tillage can also make the plough layer soil bulk density was maintained at 1.39g/cm3; plowing+rotary tillage made top-soil total porosity and aeration porosity maintained at 52%and 15%, subsoiling+rotary handle makes topsoil total porosity and aeration porosity maintained at 52%and 14%, while the subsoil aeration porosity was maintained at 12%; subsoiling can significantly increase the available phosphorus and potassium content of the topsoil and plow;(2)Subsoiling tillage rotary handle more processing comparison, can significantly increase the 20-40cm soil content of maize roots, which,20-30cm soil root dry weight, root length density, root surface area and root volume respectively increased 174%,61%,83%and 103%; 30-40cm soil root dry weight, root length density, root surface area and root volume respectively increased 83%,97%,88%and 50%.Therefore, compared to the three kinds of tillage, subsoiling tillage measures can improve the soil physical environment better, promote the growth of maize root elongation, is conducive to the improvement of crop yjeld,3. Through the different organic material fertilizer test (without application of organic materials, for 3 consecutive years returning straw and cow dung culture for 3 consecutive years fertilizer and tillage rotary tillage), studying the influence on the structure of tilth soil, the results showed:for three consecutive years cow manure fertilizer and for three consecutive years straw returning treatment, the topsoil bulk stability in 1.33 g/cm3 and 1.35g/cm3;the total porosity of the topsoil was kept at 52%and 51%, and the aeration porosity was maintained at 21%and 20%;For three consecutive years cow dung manure and straw returning is to photographic than the topsoil soil organic matter content increased of 86%and 35%; organic materials returning for a long time can significantly improve the topsoil soil total and available N, P, K content, to plow effect is not obvious.To sum up:thin topsoil, plough layer was thick, soil compaction was high, soil organic matter and available nutrients content was low, seriously restricting the improvement of corn yield in western Liaoning, through three consecutive years subsoiling rotary tillage and for three consecutive years of organic material fertilizer treatments can effectively improve and maintain the soil environment for crop growth, and promote the improvement of crop yield.Thus, it can provide scientific basis for the evaluation and construction of soil reasonable topsoil.