合理耕层能够提高土壤应对气候变化的缓冲能力,有利于协调土壤中水、肥、气、热的关系,为作物生长发育创造适宜的水热环境。借助长期定位试验,开展了玉米连作、玉米-大豆轮作以及大豆连作等不同处理下的土壤物理性状与土壤水热特征评价。土壤采样分析与田间水热定位观测发现,玉米连作处理与玉米-大豆轮作和大豆连作处理相比,可显著降低土壤容重,增加土壤总孔隙度(P<0. 05),其中0 ~ 10 cm 土壤层次下土壤容重分别降低12.9% 和19. 8%,10~20 cm层次分别低21. 4%和23. 2%,20 ~ 40 cm层次分别降低23. 9%和29. 2%,40 ~ 60 cm层次则分别降低20. 3%和25.2%;玉米连作处理可显著提高5 ~6月份土壤水分储量,特别是0 ~40 cm 土层下,玉米连作处理分别比玉米-大豆轮作和大豆连作处理高6. 5%和6. 3%、3. 6%和3.4%,且差异显著,而玉米连作处理下较高的土壤水分含量有利于促进作物前期生长和后期群体质量改善;从0 ~30 cm 土壤温度来看,不同处理间全生育期无显著差异。上述结果表明,长期玉米连作配合合理施肥可显著改善土壤结构,增加土壤水分储量,促进作物前期生长发育。
英文摘要:
Reasonable tillage can improve the buffer capacity of soil to deal with climate change, and it's helpful to coordinate the relationship of water,fertilizer,gas and heat in soil, and create suitable hydrothermal treatments. The soil physical properties and soil water and heat properties were evaluated under different treatments, such as corn continuous cropping, maizesoybean rotation and soybean continuous cropping,with the aim of providing theoretical basis and technical support for the sustainable use of black soil in Northeast China. The results of soil samples analysis and water-heat localized observation showed that CMC treatment significantly decreased soil bulk density but increased soil porosity compared to MSR and CSC treatments (P <0. 05),where the decreased rates in soil bulk density of 0 - 10 cm soil were 12. 9% and 19. 8%,also 21. 4% and 23. 2% for 10 -20 cm, 23. 9% and 29. 2% for 20-30 cm, 20. 3% and 25. 2% for 30 -40 cm, respectively. CMC treatment significantly increased soil water storage in May and June compared to the MSR and CSC environment for crop growth and development, especially for 0 - 10 cm soil layer with increased rates of 6. 5% and 6. 3%, 3. 6% and 3. 4%, respectively. The relative high soil water storage was benefit for the growth at early stage and population quality improvement at later stages in CMC treatment. Soil temperatures of 0 - 30 cm didn't significantly differ between cropping regimes in the whole growing stage. The above findings showed that the long-term corn continuous cropping with reasonable fertilization can significantly improve the soil structure, increase soil water reserves, and promote the growth and development of crops.