State Key Laboratory of Crop Biology and College of Agronomy, Shandong Agricultural University, Tai-an, Shandong, 271018, PR China.
Agronomy Department, Purdue University, 915 W State Street, West Lafayette, IN, 47907, USA.
Sci Rep. 2019 Dec 18;9(1):19335. doi: 10.1038/s41598-019-55913-1.
In pursuit of maximum grain yield farmers in the North China Plain usually apply excessive N fertilizer, resulting in wasted resources and environmental pollution. To assess the economic and environmental performances of different nitrogen rates will be conductive to sustain cleaner crop production. An 8-year field experiment was carried out with four treatments, N0 (0 kg ha for winter wheat and summer maize), N1 (168 kg ha for winter wheat and 129 kg ha for summer maize), N2 (240 kg ha for winter wheat and 185 kg ha for summer maize) and N3 (300 kg ha for winter wheat and summer maize), on the double cropping at Dawenkou research field (36°11'N, 117°06'E), Shandong Province, China. The crop production, soil physical-chemical parameters, and greenhouse gas emission are measured and the economic and environmental performances are assessed. The optimal nitrogen rate obtained the highest grain yield of summer maize in 4 of 8 year and was equivalent to conventional N rate in the other years. The nitrogen partial factor productivity and agronomic efficiency of optimal nitrogen rate was 63% and 58% higher than that of conventional nitrogen rate. The optimal nitrogen rate effectively decreased soil bulk density and increased weight percentage of water-stable aggregate and activities of urease and invertase compared to conventional nitrogen rate, which improved soil productivity. The fertilizer nitrogen loss and global warming potential of optimal nitrogen rate reduced by 76% and 35% compared to conventional nitrogen rate. The annual greenhouse gas intensity of optimal nitrogen rate decreased by 14-35% compared to others. The net ecosystem economic budget under optimal nitrogen rate is 252-604 $ ha yr. higher than other addition levels. The optimal nitrogen rate produces more grains and obtains higher economic and environmental benefits.
为追求最高粮食产量，华北平原的农民通常过量施用氮肥，造成资源浪费和环境污染。评估不同氮肥用量的经济和环境表现将有助于实现更清洁的作物生产。在中国山东省大汶口研究基地（36°11'N，117°06'E）进行了一项为期 8 年的田间试验，采用 4 种处理，N0（冬小麦和夏玉米均为 0kg/ha）、N1（冬小麦 168kg/ha，夏玉米 129kg/ha）、N2（冬小麦 240kg/ha，夏玉米 185kg/ha）和 N3（冬小麦和夏玉米均为 300kg/ha）。测量了作物产量、土壤物理化学参数和温室气体排放，并评估了经济和环境表现。最佳氮肥用量在 8 年中的 4 年获得了夏玉米的最高产量，在其余年份与常规氮肥用量相当。最佳氮肥用量的氮偏生产力和农学效率比常规氮肥用量分别提高了 63%和 58%。与常规氮肥用量相比，最佳氮肥用量有效降低了土壤容重，增加了水稳性团聚体的重量百分比和脲酶和转化酶的活性，从而提高了土壤生产力。与常规氮肥用量相比，最佳氮肥用量的肥料氮损失和全球变暖潜势分别减少了 76%和 35%。与其他处理相比，最佳氮肥用量的年度温室气体强度降低了 14-35%。最佳氮肥用量下的净生态系统经济预算比其他添加水平高 252-604 美元/公顷·年。最佳氮肥用量可生产更多粮食，获得更高的经济和环境效益。
