College of Resources and Environment, Shanxi Agricultural University, Taigu, 030801, China.
National Experimental Teaching Demonstration Center of Agricultural Resources and Environment, Shanxi Agricultural University, Taigu, 030801, China.
Environ Sci Pollut Res Int. 2019 Apr;26(10):9524-9535. doi: 10.1007/s11356-019-04337-5. Epub 2019 Feb 6.
Year-round film mulching in winter wheat field facilitates rainwater storage in summer fallow period and reduces water evaporation in growing reason, and then increases water use efficiency in the dryland of the Loess Plateau, China. Optimized fertilization further promotes fertilizer utilization efficiencies. In this study, plastic film mulching was extended from plant growth season to summer fallow, and fertilizers were applied by monitoring soil nutrient availability. Field trials were conducted in the dryland of the Loess Plateau over 4 years by using four types of cultivation to investigate the effects of year-round plastic film mulching with monitored fertilization on utilization efficiencies of rainwater and nitrogen (N), and winter wheat yield. The four types of cultivation were farmer practice (FP), ridge-furrow with plastic film mulching system plus conventional fertilization(RPCF), ridge-furrow with plastic film mulching system plus monitored fertilization (RPFM), and flat soil surface with plastic film mulching system plus monitored fertilization (FPFM). Our results indicate that the average yield of winter wheat in RPFM and FPFM treatments was 4491 kg ha. Compared with FP treatment, the combined effects of monitored fertilization and film mulching(RPFM and FPFM treatments) could increase grain yield in the range of 24.7 to 42.1%. The film mulching extended to the fallow season increased the water storage in 2 m depth of soil profile, and the amount of soil water storage in the summer fallow period increased by 27 to 30% in FPFM treatment than FP treatment. After 4-year consecutive planting of wheat, the accumulation of nitrate-N in 2 m soil reached 277 kg·ha in the FP treatment, which is 87.7% higher than of the level at the beginning of the experiment. Seventy-five percent of nitrate-N was distributed in the soil layer of 0-120 cm. In addition, the residual nitrate-N showed downward leaching with rainfall during the experiment. The RPFM and FPFM treatments reduced the apparent loss and residual levels of soil N, whereas increased its apparent mineralization compared with FP treatment. The FPFM treatment exhibited a greater utilization of residual nitrate-N from previous years and showed a higher amount of the mineralized N from soil organic matter, therefore leading to a relatively high apparent utilization rate of N (56.7%). Considering both grain yield production and utilization efficiencies of water and N, FPFM with year-round mulching was the most effective cultivation measure for winter wheat in the Loess Plateau.
在冬小麦田中全年覆膜有助于在夏闲期蓄水并减少生长季的水分蒸发，从而提高中国黄土高原旱地的水分利用效率。优化施肥进一步提高了肥料利用率。本研究将塑料薄膜覆盖从作物生长季延长到夏闲期，并通过监测土壤养分供应情况进行施肥。通过在黄土高原旱地进行了 4 年的田间试验，采用 4 种种植方式，研究了全年覆膜并监测施肥对雨水和氮（N）利用率以及冬小麦产量的影响。这 4 种种植方式为农民传统种植（FP）、垄膜沟灌加常规施肥（RPCF）、垄膜沟灌加监测施肥（RPFM）和平地全膜覆盖加监测施肥（FPFM）。结果表明，RPFM 和 FPFM 处理下冬小麦的平均产量为 4491kg·ha-1。与 FP 处理相比，监测施肥与覆膜（RPFM 和 FPFM 处理）的综合效应可使产量提高 24.7%至 42.1%。覆膜延伸到休耕期，增加了 2m 土壤剖面的储水量，FPFM 处理比 FP 处理在夏闲期的土壤储水量增加了 27%至 30%。连续 4 年种植小麦后，FP 处理下 2m 土壤中硝态氮的积累量达到 277kg·ha-1，比实验开始时的水平高 87.7%。75%的硝态氮分布在 0-120cm 的土层中。此外，在实验过程中，硝态氮的残留随降雨向下淋洗。与 FP 处理相比，RPFM 和 FPFM 处理减少了土壤氮的表观损失和残留水平，同时增加了其表观矿化。FPFM 处理表现出对前一年残留硝态氮的更高利用，以及对土壤有机质矿化氮的更高利用，因此具有相对较高的氮表观利用率（56.7%）。考虑到水分和氮的产量和利用效率，全年覆膜的 FPFM 是黄土高原冬小麦最有效的种植措施。
