College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
Institute of Bio- and Geosciences, Agrosphere (IBG-3), Research Centre Jülich, Jülich 52425, Germany.
Sci Total Environ. 2017 Oct 15;596-597:61-68. doi: 10.1016/j.scitotenv.2017.04.064. Epub 2017 Apr 14.
Global population increase will require rapid increase of food production from existing agricultural land by 2050, which will inevitably mean the increase of agricultural productivity. Due to agricultural sustainable intensification since the 1990s, crop production in Huantai County of northern China has risen to 15thayr for the annual wheat-maize rotation system. We examined the temporal dynamics of nitrogen (N) budget, N losses, and N use efficiency (NUE) during the 35years (1980-2014) in Huantai. The results revealed that atmospheric N deposition increased 220% while reactive N losses decreased by 21.5% from 1980s to 2010s. During 1980-2002, annual N partial factor productivity (PFP), apparent NUE and N recovery efficiency (RE) increased from 20.3 to 40.7kggrainkgN, from 36.5% to 71.0%, and from 32.4% to 57.7%, respectively; meanwhile, reactive N losses intensity, land use intensity and N use intensity decreased by 69.8%, 53.4%, 50.0%, respectively, but without further significant changes after 2002. Overall increases in NUE and decreases in N losses were largely due to the introduction of optimized fertilization practice, mechanization and increased incorporation of crop straw in Huantai. Straw incorporation was also significant in soil N stock accrual and fertility improvement. By 2030, northern China may reach the lowest end of PFP values in developed countries (>45kggrainkgN). These agricultural sustainable intensification practices will be critical in maintaining high grain yields and associated decreases in environmental pollution, although water use efficiency in the region still needs to be improved.
全球人口增长将要求在 2050 年前从现有的农业土地上快速增加粮食产量，这不可避免地意味着农业生产力的提高。由于 20 世纪 90 年代以来农业的可持续集约化，中国北方桓台县的作物产量已上升到每年冬小麦-夏玉米轮作系统的 15 吨。我们考察了 35 年来（1980-2014 年）桓台县氮（N）预算、N 损失和 N 利用效率（NUE）的时间动态。结果表明，大气 N 沉积增加了 220%，而从 20 世纪 80 年代到 2010 年代，活性 N 损失减少了 21.5%。1980-2002 年期间，年 N 偏生产力（PFP）、表观 NUE 和 N 回收效率（RE）分别从 20.3 到 40.7kg 小麦-玉米 kgN、从 36.5%到 71.0%和从 32.4%到 57.7%增加；同时，活性 N 损失强度、土地利用强度和 N 利用强度分别减少了 69.8%、53.4%和 50.0%，但 2002 年后没有进一步显著变化。NUE 的总体增加和 N 损失的减少在很大程度上归因于优化施肥实践、机械化和作物秸秆在桓台的增加投入。秸秆还田对土壤 N 储量的增加和肥力的提高也很重要。到 2030 年，中国北方可能达到发达国家 PFP 值的最低端（>45kg 小麦-玉米 kgN）。这些农业可持续集约化实践将在维持高粮食产量和减少相关环境污染方面至关重要，尽管该地区的水资源利用效率仍需提高。
