Different Tillage Methods On Western Liaoning Brown Soil Aggregate Size Distribution And Its Organic Carbon Oxidation Stability Influence

The main area of Liaoning Province Area in Liaoning Province as the corn planting, factors influencing maize yield level of the audience, in addition to the annual rainfall is less and the concentration of natural environmental factors, soil factors have become an important problem to restrict the yield is not high, such as soil organic matter content in western Liaoning, dominated by shallow tillage the rotary tillage depth, the soil becomes shallow, and lead to plowpan thickening and hardening, water retention caused soil holding capacity is weak, the lower soil is not conducive to the root. Although the loess, black soil types of soil aggregates and organic carbon research more, but for the aggregate in cinnamon soil area few studies, micro organic carbon content and oxidation stability of aggregate and aggregate in. Therefore, this article through to the soil as the research object, carries on the experiment, the rotary tillage, subsoiling, No tillage, rotary tillage, subsoiling and straw, affect the organic carbon content of soil aggregates and organic carbon in aggregates and the oxidation stability of 5 kinds of different tillage methods, the research results are as follows:1. Study on the influence of western Liaoning area cinnamon soil mechanical stability of the aggregates and water stable aggregates and aggregate stability under different tillage methods:The mechanical stability of the aggregates concentrated in more than 5mm grade, water stable aggregates are mainly concentrated in 2mm-0.25mm fraction.Compared to the other 4 kinds of rotary tillage, treatment increased the aggregate content in different soil layers grain size in different degrees. mechanical stability of soil aggregate and large aggregate content of water stability, straw returned+deep loosening the highest; Mechanical stability of soil aggregate up to an average weight diameter of straw returned+deep processing, and improve the water stability of soil aggregate average weight diameter in order to avoid the tillage treatment and returning straw+deep loosening effect is good. In reducing the aggregate on the breaking rate of straw returned+deep loosening treatment of broken rate for 5 kinds of lowest.. On the whole, in increasing the number of aggregates partialfractions content and aggregate quantity, improving aggregate stability, straw the effect of deep loosening is best.2. The effects of different tillage methods on the organic carbon content and oxidation stability of organic carbon in soil aggregate were studied:Compared with rotary tillage, deep loosening and minimum tillage could increase the total organic carbon in different degree and aggregate organic carbon content at every level, straw returned can also continue to increase the content of organic carbon, straw returned+deep loosening in improving total organic carbon and each fraction organic carbon content in the aggregate to increase the size of the largest. On improving aggregate organic carbon oxidation stability, the effect of no-till optimal, straw returned+deep loosening effect. Taken together, straw returned+deep loosening of farming in the increase of organic carbon content in the aggregate and the effect of organic carbon on the oxidation stability is best.3. The size distribution of micro aggregates with the increase of soil depth and no obvious regularity.In different depth of soil micro aggregates with 0.05 mm to 0.01 mm the largest number of graded, compared with rotary tillage, deep loosening, straw returned+ rotary tillage and straw returned, deep loosening raised> 0.01 mm graded aggregate content, reduced the< 0.01 mm fraction content of soil; Straw counters-field compared with no straw returned, also presented the same law; Deep loosening, straw returned with rotary tillage or deep loosening all can reduce soil characteristics of the micro aggregate proportion,5 kinds of treatment of straw counters-field+deep loosening the characteristics of the lowest; Micro aggregate of soil organic carbon content and oxidative organic carbon content, straw returned the highest+deep loosening process, organic carbon oxidation stability coefficient of the highest treatment for zero tillage treatment.To sum up, improve soil quality in maize field in western Liaoning, improve soil aggregate content and aggregate stability, organic carbon and easy (difficult) organic carbon content and oxidation stability of oxidation, the optimal comprehensive effect of straw+subsoiling.