Wen Mei Juan, Wang Cheng Bao, Huo Lin, Jiang Wan Li, Yang Si Cun
Ministry of Agriculture Scientific Observing and Experiment Station of Agro-Environment and Arable Land Conservation in Gansu, Institute of Soil Fertilizer and Water-saving Agriculture, Gansu Academy of Agriculture Sciences, Lanzhou 730070, China.
Ying Yong Sheng Tai Xue Bao. 2019 Jan 20;30(1):224-232. doi: 10.13287/j.1001-9332.201901.030.
A field experiment was conducted to examine the effects of subsoiling 35 cm with maize straw returning, subsoiling 35 cm without maize straw returning, and rotary tillage without maize straw returning on soil compaction, soil bulk density, soil infiltration, soil water content in 0-100 cm depth, nutrients uptake and production of maize on sierozem in the Gansu Yellow River irrigated area in 2015-2017. Compared with subsoiling 35 cm without maize straw returning and rotary tillage without maize straw returning, subsoiling 35 cm with maize straw returning significantly decreased the soil compaction and soil density in 0-40 cm depth. Compared with that in 2015 (before experiment), soil compaction and soil bulk density in subsoiling 35 cm with straw returning was decreased by 42.6% and 7.0%, respectively, after harvest in 2017. Compared with other treatments, subsoiling 35 cm with straw returning had the lowest variation of soil compaction (6.1%) and soil bulk density (3.2%) in 0-40 cm depth before sowing and after harvest in 2016 and 2017. The soil infiltration rate in subsoiling 35 cm with straw returning was significantly improved by 33.6% compared with rotary tillage without maize straw returning. Subsoiling 35 cm with straw retention could significantly increase soil water content and decrease water variation in 0-100 cm soil depth in spring (before maize sowing) and autumn (after maize harvest). Compared with rotary tillage without maize straw returning, water storage in subsoiling 35 cm with straw retention was increased by 15.5% and 5.6% in spring and autumn, respectively. The water use efficiency was enhanced by 32.4%. Furthermore, subsoiling 35 cm with straw retention could increase maize economic yield and biomass yield by 25.6% and 33.3%, compared with rotary tillage without straw retention. Subsoilng and straw retention could promote nutrient absorption, with N, PO and KO uptake increased by 49.6%, 51.5% and 37.6%, compared with rotary tillage. Overall, our results suggested that subsoiling 35 cm straw retention could improve soil characteristics, stabilize the phy-sical properties of the plough layer, increase soil water content in the 0-100 cm soil layer, and reduce water variation in spring and autumn. Consequently, it was the best management to promote the water and nutrient utilization of maize and achieve high yield. Our findings could provide theoretical basis for further research on the construction technology of the plough layer in Gansu irrigation area.
2015 - 2017年，在甘肃黄河灌区的灰钙土上进行了田间试验，研究了深耕35 cm并秸秆还田、深耕35 cm不秸秆还田以及旋耕不秸秆还田对土壤紧实度、土壤容重、土壤入渗、0 - 100 cm土层土壤含水量、玉米养分吸收和产量的影响。与深耕35 cm不秸秆还田和旋耕不秸秆还田相比，深耕35 cm并秸秆还田显著降低了0 - 40 cm土层的土壤紧实度和土壤密度。与2015年（试验前）相比，2017年收获后，深耕35 cm并秸秆还田的土壤紧实度和土壤容重分别降低了42.6%和7.0%。与其他处理相比，2016年和2017年播种前和收获后，深耕35 cm并秸秆还田在0 - 40 cm土层的土壤紧实度变化（6.1%）和土壤容重变化（3.2%）最小。深耕35 cm并秸秆还田的土壤入渗率比旋耕不秸秆还田显著提高了33.6%。深耕35 cm并保留秸秆能显著增加春季（玉米播种前）和秋季（玉米收获后）0 - 100 cm土层的土壤含水量，并减少水分变化。与旋耕不秸秆还田相比，深耕35 cm并保留秸秆在春季和秋季的储水量分别增加了15.5%和5.6%。水分利用效率提高了32.4%。此外，与旋耕不保留秸秆相比，深耕35 cm并保留秸秆可使玉米经济产量和生物量产量分别提高25.6%和33.3%。深耕和保留秸秆能促进养分吸收，与旋耕相比，氮、磷、钾吸收量分别增加了49.6%、51.5%和37.6%。总体而言，我们的结果表明，深耕35 cm并保留秸秆可改善土壤特性，稳定耕层物理性质，增加0 - 100 cm土层土壤含水量，减少春秋季水分变化。因此，这是促进玉米水分和养分利用并实现高产的最佳管理措施。我们的研究结果可为甘肃灌区耕层构建技术的进一步研究提供理论依据。
