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With the changes in the global climate and environment, conservation tillage and soil carbon and nitrogen has become a worldwide concern. In this paper, wheat and corn rotation under the conditions of the Guanzhong area, which lasted seven years of different tillage (subsoiling, rotary tillage, no-tillage, conventional tillage) location test for the study, research conservation tillage on the Lou soil organic carbon content, active combining form; distribution of soil structure and the carbon and nitrogen content of the soil structure, organic carbon oxidation stability; soluble organic carbon and nitrogen content of the soil and the nature of humification. The main conclusions are as follows: 1. Studied under different tillage treatments (subsoiling, rotary tillage, no-tillage, straw under conventional tillage, conventional tillage) total organic carbon of the soil layer, high organic carbon content of the active as well as pine knot state stability knot state tight end state of the organic carbon content, and calculate the the loose knot organic carbon, tight knot organic carbon ratio (loose / tight). Compared with conventional tillage in wheat straw high stubble case, regardless of whether the corn stalks to field rotavator, subsoiling and no-tillage treatment can not only improve the soil organic carbon content, but also to improve the activity of soil organic carbon and pine knot The state of the organic carbon content and increase the ratio of the loose knot organic carbon tight knot organic carbon, and the effect of subsoiling and rotary more than no-till. Study the impact of conservation tillage on the distribution of soil aggregates and aggregates in carbon and nitrogen and organic carbon oxidation stability. Each treatment, gt; 5 mm grain size aggregates the most abundant, accounting aggregates total 62.3% to 70.2%, the minimum content of 0.5 to 0.25 mm grain size of the aggregates, accounting for 1.10% of the total aggregates to 1.80%. Compared to conventional tillage, subsoiling, rotary tillage, no-till, and straw traditional farming gt; 5mm grain size aggregates content. With soil aggregate size increases, the organic carbon content of the aggregates gradually decreases, including organic carbon content in lt; 0.25 mm aggregates content, with an average of 10.87 g.kg-1. Gt; 5 mm aggregates, minimum, average 9.57 g.kg-1. , Total nitrogen content in gt; 0.25 mm of the size of the aggregates, with increasing aggregate size decreases. Average 1.18 g.kg-1, total nitrogen content in the grain size of 0.5 ~ 0.25 mm aggregates gt; 5 mm grain size aggregates smallest total nitrogen content, an average of 0.99 g.kg-1. Subsoiling and rotary tiller handle than the no-till and conventional tillage is more conducive to the increase in aggregates of organic carbon, nitrogen content. Subsoiling, rotary tillage, no-tillage and straw under conventional tillage increased the size of the aggregates easily oxidized organic carbon content and subsoiling and rotary effects reach a significant level, no-till is not remarkable; subsoiling spin tillage, no-tillage difficult to oxidize organic carbon content was not significantly. Various conservation tillage on the improvement of the total organic carbon content of the soil aggregates is achieved by the improvement of the organic carbon content is easily oxidized aggregates. Various conservation tillage reduces the oxidation of organic carbon in aggregates stability coefficient (Kos), but did not reach a significant level. Soil smaller size fraction (0.5 ~ 0.25 mm and lt; 0.25 mm) aggregates in the TOC, easily oxidized and difficult to oxidize organic carbon content than the large size of the aggregates (gt; 0.5 mm) high, and the lower oxidation stability factor (Kos). Conservation tillage on soil micro-aggregates distribution and micro-aggregates carbon and nitrogen and organic carbon oxidation stability. The straw crushing rotavator, straw mulch subsoiling to improve the characteristics of micro-aggregates composed proportion straw conventional tillage and no-tillage treatment microaggregates smaller ratio features. Compared with conventional tillage, rotary tillage, subsoiling could improve organic carbon and total nitrogen content of micro-aggregates of larger size fraction (0.05 ~ 0.25 mm and 0.01 ~ 0.05 mm), and no-till 0.01 ~ 0.05 mm micro-aggregates in organic carbon and nitrogen content decreased; rotary tillage, subsoiling and no-tillage the arabica-level micro-aggregates (lt; 0.01mm) in organic carbon and total nitrogen content was less affected. Rotary cultivator and subsoiling make TOC, easily oxidized organic carbon, difficult to oxidize organic carbon content significantly increased from 0.05 to 0.25 and 0.01 ~ 0.05 mm micro-aggregates in lt; decreased micro-aggregates of 0.01 mm; subsoiling and rotary micro-aggregates of organic carbon oxidation stability not reach a significant level, the zero tillage significantly lower fractions of micro-aggregates of organic carbon oxidation stability. Lou soil micro-aggregates of organic carbon content and oxidation stability depends on the to favor 0.05 ~ 0.25 mm the microaggregates body, subsoiling, rotavator microaggregates reduction in the accumulation of organic carbon content in the body and the organic carbon oxidation stability. The 4. Straw combined with the impact of different tillage methods on soil soluble organic carbon and nitrogen content and humification nature. Loess soil, dissolved organic carbon, nitrogen content between 44.40 ~ 66.67 mg / kg and 2.64 ~ 6.16 mg / kg, respectively. Compared to conventional tillage, subsoiling, rotary tillage, no-tillage and straw under conventional tillage treatments enhanced soil soluble organic carbon content. In addition to the bare ground zero tillage farming measures were also increased soluble organic nitrogen content and subsoiling and rotary improve soil soluble organic carbon, the effect of organic nitrogen. Comparison with conventional tillage, in the case of returning corn straw, subsoiling, rotary processing the soil soluble organics UV280 elevated, reflecting the increase in soluble organic compounds, aromatic compounds, the humification strengthen; rotavator subsoiling, no-tillage and straw traditional farming humification index of dissolved organic matter (HIXem) was increased, and pine straw mulch light. Correlation analysis showed significant correlation between soil soluble organic carbon, total nitrogen and soluble carbon, nitrogen, and soil organic carbon, total nitrogen content.
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