Peng Zhengping, Liu Yanan, Li Yingchun, Abawi Yahya, Wang Yanqun, Men Mingxin, An-Vo Duc-Anh
College of Resources and Environmental Sciences, Key Laboratory for Farmland Eco-Environment of Hebei, Agricultural University of Hebei Baoding, China.
Key Laboratory of Agricultural Environment, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Agricultural Ministry of China Beijing, China.
Front Plant Sci. 2017 Feb 8;8:160. doi: 10.3389/fpls.2017.00160. eCollection 2017.
Nitrogen (N) is an essential macronutrient for plant growth and excessive application rates can decrease crop yield and increase N loss into the environment. Field experiments were carried out to understand the effects of N fertilizers on N utilization, crop yield and net income in wheat and maize rotation system of the North China Plain (NCP). Compared to farmers' N rate (FN), the yield of wheat and maize in reduction N rate by 21-24% based on FN (RN) was improved by 451 kg ha, N uptakes improved by 17 kg ha and net income increased by 1671 CNY ha, while apparent N loss was reduced by 156 kg ha. The controlled-release fertilizer with a 20% reduction of RN (CRF80%), a 20% reduction of RN together with dicyandiamide (RN80%+DCD) and a 20% reduction of RN added with nano-carbon (RN80%+NC) all resulted in an improvement in crop yield and decreased the apparent N losses compared to RN. Contrasted with RN80%+NC, the total crop yield in RN80%+DCD improved by 1185 kg ha, N uptake enhanced by 9 kg ha and net income increased by 3929 CNY ha, while apparent N loss was similar. Therefore, a 37-39% overall decrease in N rate compared to farmers plus the nitrification inhibitor, DCD, was effective N control measure that increased crop yields, enhanced N efficiencies, and improved economic benefits, while mitigating apparent N loss. There is considerable scope for improved N use effieincy in the intensive wheat -maize rotation of the NCP.
氮（N）是植物生长必需的大量元素，过量施用会降低作物产量并增加氮素向环境中的流失。在中国华北平原（NCP）的小麦-玉米轮作系统中进行了田间试验，以了解氮肥对氮素利用、作物产量和净收益的影响。与农民的施氮量（FN）相比，基于FN降低21%-24%的施氮量（RN），小麦和玉米的产量提高了451 kg/ha，氮素吸收量提高了17 kg/ha，净收益增加了1671元/ha，同时表观氮素流失减少了156 kg/ha。与RN相比，施氮量降低20%的控释肥料（CRF80%）、施氮量降低20%并添加双氰胺的肥料（RN80%+DCD）以及施氮量降低20%并添加纳米碳的肥料（RN80%+NC）均提高了作物产量并降低了表观氮素流失。与RN80%+NC相比，RN80%+DCD的作物总产量提高了1185 kg/ha，氮素吸收量增加了9 kg/ha，净收益增加了3929元/ha，而表观氮素流失相似。因此，与农民的施氮量相比总体降低37%-39%并添加硝化抑制剂双氰胺是有效的氮素控制措施，可提高作物产量、增强氮素利用效率、改善经济效益，同时减少表观氮素流失。在华北平原集约化小麦-玉米轮作中，提高氮素利用效率仍有很大空间。
