深翻－旋耕轮耕与有机肥配施对黑土农田土壤物理性质的影响

针对东北松嫩平原中南部黑土区玉米带农田长期旋耕导致耕层变浅、容重增大等问题，开展深翻-旋耕轮耕模式改善土壤物理性质的研究。试验设置连年旋耕配施化肥（RT）、连年旋耕配施化肥与有机肥（RM）、深翻－旋耕轮耕配施化肥（DT）和深翻－旋耕轮耕配施化肥与有机肥（DM）4个处理，分析0 ~ 45 cm土壤含水量、容重、紧实度、团聚体的变化及10 cm、20 cm、30 cm各深度处土壤温度变化情况。结果表明，与RT处理相比，DT处理能够显著提高玉米苗期和拔节期20 cm、30 cm深度土壤温度，增加玉米各生育时期15 ~ 45 cm土层土壤含水量，并且显著降低土壤容重和紧实度，提高了30 ~ 45 cm土层 > 0.25 mm水稳性团聚体的比例；同时DM处理能够增加苗期、收获期各土层含水量，且对0 ~ 45 cm土壤容重均有显著降低作用；而RM处理仅使0 ~ 15 cm土层容重有降低，但并不显著，且对深层土壤容重无明显影响。相关分析表明，在0 ~ 15 cm土层中，土壤含水量、紧实度、容重与温度呈负相关关系（P < 0.05）；在0 ~ 45 cm土层中，土壤容重与土壤紧实度呈极显著正相关关系（P < 0.05）。DM的耕作模式能降低土壤容重和紧实度，有效提高土壤温度、土壤含水量以及 > 0.25 mm 水稳性团聚体的比例，能够较好的改善土壤耕层物理性质。

Effects of Deep Ploughing-rotary Tillage Combined with Organic Fertilizer on Black Soil Physical Properties

Considering the change in soil physical properties caused by long-term rotary tillage such as lower plough layer and higher bulk density in the northeast corn belt, rotational tillage system were conducted in the black soils of the central and southern Songnen Plain, which is of great importance to improve soil physical properties. The experiment was set up two tillage systems: consecutive rotary tillage (R), deep ploughing-rotary tillage (D), in combination with two fertilizer managements: chemical fertilizer (T), chemical fertilizer + organic fertilizer (M). Soil moisture content, bulk density, soil compaction at 0-50 cm soil depth and soil temperature at 10 cm, 20 cm and 30 cm soil depth were determined. The results showed that deep ploughing-rotary tillage significantly increased soil temperature at 20 and 30 cm soil depth during maize seedling stage and improved the soil moisture content at 15-50 cm soil depth in each growth stage. The application of organic fertilizer could increase the soil moisture content during the seedling and harvest stage. The soil bulk density and compactness at 15-50 cm soil depth under deep ploughing-rotary tillage were significantly reduced and the addition of organic fertilizer in this treatment significantly reduced the soil bulk density at 0-50 cm soil depth, which meets the requirement of breaking the plough pan layer. However, the application of organic fertilizers in consecutive rotary tillage only significantly decreased the soil bulk density at 0-15 cm soil depth. Correlation analysis indicated that the soil moisture content was negatively correlated with soil temperature (P > 0.05). The soil bulk density had a significant negative correlation with soil temperature under deep ploughing-rotary tillage (P < 0.01). It could be concluded that deep-rotary tillage could decrease soil bulk density and compaction, regulate soil temperature, improve soil moisture content. Therefore, the deep ploughing-rotary tillage with the addition of organic fertilizer and chemical fertilizer is a promising strategy in improving soil physical properties in black soils of Northeast China and similar regions.