Area of Norway assigned to WWF biomes.

Nitrogen is a chemical element that is cycled through Earth’s lithosphere, hydrosphere, cryosphere and atmosphere, as well as a crucial component of the molecular machinery of life. Being an intrinsic part of the biosphere, the flow of nitrogen in a country can provide unique insights into the sustainability of a society. This study investigates how nitrogen is used in Norway between 1961 and 2020. Nitrogen inputs from atmospheric deposition, biological nitrogen fixation and from weathering, as well as from synthetic fertilizers are addressed. These sources of nitrogen are used by plants that form the basis of agriculture and forestry. Nitrogen, in the form of protein, is imported to sustain the Norwegian population and the production of animals in agriculture and fisheries. Agricultural livestock is used almost exclusively for domestic consumption, while fish captured and raised in aquaculture are the main sources of exported food. Even though petroleum and wood contain only a small proportion of nitrogen, due to the traded volume, a large amount of nitrogen contained in these goods is exported. Nitrogen is lost through sewage and manure leaching, as well as atmospheric emissions. These emissions are mostly in the form of nitrogen oxides and ammonia, which are released by burning fossil fuels and metabolizing animals, respectively.

氮是一种化学元素，在地球岩石圈、水圈、冰冻圈与大气圈之间循环往复，同时也是生命分子运作机制的关键组分。作为生物圈的固有组成部分，一国范围内的氮素流动可为社会可持续性评估提供独特视角。本研究聚焦1961年至2020年间挪威的氮素使用状况展开分析，涵盖大气沉降、生物固氮、岩石风化以及合成肥料等各类氮素输入途径。上述氮素来源为构成农林产业基础的植物所吸收利用。以蛋白质形态存在的氮素会通过进口流入国内，以保障挪威国民需求以及农林渔业的畜禽养殖生产。农业养殖的畜禽产品几乎全部用于国内消费，而捕捞及水产养殖所得水产品则是该国出口食品的主要来源。尽管石油与木材的氮素占比极低，但凭借庞大的贸易体量，此类商品所承载的氮素出口总量依然可观。氮素会通过污水排放、粪便淋溶以及大气排放等途径流失，这类大气排放物主要为氮氧化物与氨，分别源自化石燃料燃烧与动物新陈代谢过程。