Hou Sen, Fu Quanjuan, Li Huifeng, Gao Rui, Sun Yugang, Wei Guoqin
National Laboratory Institution, State Key Laboratory of Nutrient Use and Management, Jinan, Shandong, China.
Shandong Institution of Pomology, Taian, Shandong, China.
Front Plant Sci. 2024 Nov 1;15:1482292. doi: 10.3389/fpls.2024.1482292. eCollection 2024.
To ensure higher productivity, fertilizers have been excessively applied to the fruit greenhouse soil yearly, thus resulting in the increasing risks of residual nitrate leaching in the North China Plain.
In this study, a water and solute transport HYDRUS-1D model was used to evaluate the effects of using sweet corn as a catch crop on deep water drainage and nitrate leaching in a sweet cherry greenhouse soil. A three-year (2019-2021) field experiment was conducted during the rainfall season from July to September in the post-harvest of sweet cherry, when the plastic cover was removed each year. In the experiment, the five treatments were designed. The three nitrate residue levels denoted by CKR, N1R, and N2R, represented nitrate residue amounts in the soil profile of three nitrogen fertilizer levels(0, 280 and 420kg ha) before the harvest of sweet cherry(March to June). Two other treatments with and without sweet corn as a catch crop based on the treatments of N1R and N2R were denoted by N1RC and N2RC, respectively. The data of both the spatial and temporal distribution of water and nitrate content during the rainy seasons of 2019, 2020 and 2021 in the field experiment were collected to calibrate and validate the model.
The simulated results have showed that using sweet corn as a catch crop increased the evapotranspiration rate, the upward flux of water and nitrate at a 100 cm soil depth reached a maximum of 1.5 mm d and 1.0 kg N had, respectively, and the downward movement of water and nitrate leached to deeper soil layers was reduced. Compared with CKR, the treatments with catch crops (N1RC and N2RC) reduced the amount of water drainage by 16.4% -47.7% in the 0-180cm soil profile. The average amounts of nitrate leaching in the 1.8 m soil profile during the three-year experiment were 88.1, 113.3, and 58.2 kg N ha for the treatment without catch crop (N1R and N2R) and 32.3, 54.8, and 31.4 kg N ha for the treatment with catch crop (N1RC and N2RC), respectively. The treatments (N1RC and N2RC) with catch crops decreased the amount of nitrate leaching by 29.6%-69.1% compared with the treatments without catch crops (N1R and N2R).
Sweet corn as summer catch crop can reduce nitrate leaching in the sweet cherry greenhouses. Our study has provided an effective method to reduce the risk of nitrate leaching for sweet cherry greenhouses in the North China Plain.
为确保更高的产量，每年都向水果温室土壤中过量施用化肥，从而导致华北平原硝酸盐残留淋失风险增加。
在本研究中，使用水和溶质运移HYDRUS-1D模型评估在甜樱桃温室土壤中种植甜玉米作为填闲作物对深层排水和硝酸盐淋失的影响。在甜樱桃收获后的7月至9月降雨季节进行了为期三年（2019 - 2021年）的田间试验，每年此时移除塑料棚膜。试验设计了五个处理。CKR、N1R和N2R表示的三个硝酸盐残留水平，代表甜樱桃收获前（3月至6月）三种氮肥水平（0、280和420 kg/ha）下土壤剖面中的硝酸盐残留量。基于N1R和N2R处理，另外两个种植和不种植甜玉米作为填闲作物的处理分别表示为N1RC和N2RC。收集了2019年、2020年和2021年田间试验雨季期间水和硝酸盐含量的时空分布数据，用于校准和验证模型。
模拟结果表明，种植甜玉米作为填闲作物增加了蒸散速率，100 cm土壤深度处水和硝酸盐的向上通量分别达到最大值1.5 mm/d和1.0 kg N/ha，减少了水和硝酸盐向下层土壤的淋溶。与CKR相比，种植填闲作物的处理（N1RC和N2RC）在0 - 180 cm土壤剖面中排水量减少了16.4% - 47.7%。三年试验期间，1.8 m土壤剖面中，不种植填闲作物的处理（N1R和N2R）硝酸盐淋溶平均量分别为88.1、113.3和58.2 kg N/ha，种植填闲作物的处理（N1RC和N2RC）分别为32.3、54.8和31.4 kg N/ha。种植填闲作物的处理（N1RC和N2RC）与不种植填闲作物的处理（N1R和N2R）相比，硝酸盐淋溶量减少了29.6% - 69.1%。
甜玉米作为夏季填闲作物可减少甜樱桃温室中的硝酸盐淋失。我们的研究为降低华北平原甜樱桃温室硝酸盐淋失风险提供了一种有效方法。
