Integrated Nitrogen Management System (Pump priming)

氮化合物是生命所必需的。它们是制造许多生物化合物所必需的，包括蛋白质、氨基酸、DNA和三磷酸腺苷（细胞的“燃料来源”），没有它们，任何生物体都无法生存。氮尤其重要，因为它经常限制粮食生产，而环境中高浓度的氮化合物会导致严重的污染问题。通过提供氮肥，农民大大提高了产量。这对于养活上个世纪不断增长的世界人口至关重要，据估计，氮肥养活了约35亿人，几乎是世界人口的一半。虽然活性氮源的制造和动员的增加可以被视为“地球工程”的伟大壮举，但也有许多意想不到的后果。不断增长的人口需要更多的食物，因此需要更多的肥料，特别是我们现在人均食用更多的动物产品。其结果是一个复杂的污染问题网络，威胁着水、空气和土壤质量，改变气候平衡，影响生态系统和人类健康。除了农场氮的损失外，其他来源也不容忽视。其中包括燃烧产生的空气排放，以及污水系统对水的损失。总的来说，人类对全球氮循环的改变构成了一个与气候变化并列的多重问题，是21世纪的重大挑战之一。欧洲氮素评估估计，单是氮素污染每年就在整个欧盟造成700 - 3200亿欧元的损失（Nature， 2011年4月14日，472,159）。考虑到氮流失到环境中的途径的多样性，有许多潜在的解决方案。在最近由CEH为联合国环境规划署（UNEP， 2013年2月发布）牵头的《我们的营养世界》报告中，确定了10项关键行动，这些行动将有助于改善营养管理，同时有助于实现粮食安全目标，减少空气、土地和水的污染，对生态系统、气候和人类健康有多重好处。然而，《我们的营养世界》也指出，目前还没有全球性的国际协议将氮的诸多益处和威胁联系起来。因此，也没有协调的科学评估和支助过程来量化和证明这些联系。目前，NERC的国际机会基金（IOF）正在通过支持一项新的努力“向国际氮管理系统（简称INMSpp）注入资金”来解决这一差距。其核心思想是，需要一个科学支持系统，能够提供必要的证据，显示全球氮循环的联合管理将如何带来多重效益，并能够评估政策制定者可能希望考虑的选择。联合国全球环境基金（GEF）邀请NERC生态与水文中心（CEH）与环境署合作，制定一个概念，以建立未来的INMS方法，这反映了INMS的发展雄心。最终，这将是一项重大努力，将指标、模型和数据集联系起来，以便对可能达成的国际协定进行评估。INMS泵启动项目为实现这一最终目标迈出了关键一步。作为建立从源头到影响再到缓解和适应的模式链的关键挑战之一，该项目承担了研究如何开发氮循环综合全球模式的任务。该项目将召集一个全球财团，研究如何将各种模型联合起来，以证明更好的氮管理的净效益。随着INMS方法的发展，这将是一个关键的资源。其结果有望表明，将不同的国际环境协议联系起来如何能够建立共同点，同时支持粮食和能源安全以及更清洁的环境。

Nitrogen compounds are essential for life. They are needed to make many biological compounds including proteins, amino acids, DNA and ATP (the 'fuel source' of cells), without which no living organism could survive. Nitrogen is particularly important because it often limits food production, while high levels of N compounds in the environment lead to serious pollution problems. By supplying N fertilizers, farmers greatly improve their yields. This has been essential to feed the growing world population over the last century, with N fertilizers estimated to sustain ~3.5 billion people, almost half of humanity.While the increased manufacture and mobilization of reactive N sources can be seen as a great feat of 'geoengineering', there have been many unintended consequences. A growing human population needs more food, so more fertilizers, especially as we now eat more animal products per person. The result is a complex web of pollution issues, threatening water, air and soil quality, altering climate balance and impacting on ecosystems and human health. In addition to the loss of N from farms, other sources cannot be forgotten. These include air emissions from burning, and losses to water from sewage systems. Overall, human alteration of the global N cycle makes for a multi-issue problem that ranks alongside climate change as one of the great challenges of the 21st century. The European Nitrogen Assessment has estimated that N pollution alone causes 70-320 billion Euro per year of damage across the EU (Nature, 14 April 2011,472,159).Given the wide diversity of nitrogen loss pathways into the environment, there are many potential solutions. In a recent report 'Our Nutrient World' led by CEH for the United Nations Environment Programme (UNEP, launched Feb 2013), 10 key actions were identified which would contribute to better nutrient management, simultaneously helping to meet food security goals while reducing the pollution of air, land and water, with multiple benefits for ecosystems, climate and human health. However, 'Our Nutrient World' also identified that there is currently no global international agreement that links the many benefits and threats of nitrogen. As a result, there is also no coordinated scientific assessment and support process to quantify and demonstrate these linkages. This gap is now being addressed by the International Opportunities Fund (IOF) of the NERC through its support for a new endeavour "Pump priming to towards the International Nitrogen Management System" - or 'INMSpp' for short.The central idea is that a scientific support system is needed that can provide the evidence needed to show how joined-up management of the global nitrogen cycle will deliver multiple benefits, and to be able to evaluate options that policy makers may wish to consider. Already there is a developing ambition for INMS as reflected by the invitation from the UN Global Environment Facility (GEF) for the NERC Centre for Ecology and Hydrology (CEH) to work with UNEP to develop a concept to establish a future INMS approach. Ultimately this would be a major endeavour, linking indicators, models and datasets to allow evaluation of possible international agreements. The INMS pump priming project provides a key step towards this eventual goal. As one of the key challenges to establish model chains from source to impact to mitigation and adaptation the INMSpp project has taken on the task of working out how integrated global modelling of the nitrogen cycle should be developed. The project will bring together a global consortium to examine how models can be joined up to demonstrate the net benefits of better nitrogen management. This will be a key resource as the INMS approach is developed. The outcome is the prospect to show how linking up different international environmental agreements can build common ground, simultaneously supporting food and energy security and a cleaner environment.