Workshop: Feeding the World in the 21st Century: Grand Challenges in the Nitrogen Cycle; Arlington, VA - November 9-10, 2015

化学部的化学催化项目和化学、生物、环境和运输系统部的环境工程项目赞助了这次题为“21世纪养活世界：氮循环中的重大挑战”的研讨会，该研讨会将于2015年11月9日至10日在弗吉尼亚州阿灵顿举行。氮循环是地球上最重要的生物地球化学循环之一，因为氮是所有生命形式必需的营养物质。氮的最大储存库是大气中的气态二氮；然而，这种形式的氮不能被植物直接利用，因此在许多情况下，获得固定形式的氮是植物生长和粮食生产的最限制因素。氮的第二个最重要的储存库是硝酸盐，以无机矿物质和肥料的形式存在，这种形式的氮很容易被生活在土壤和水中的植物和微生物吸收。提高农作物产量的一个重要历史因素是哈伯-博世工艺的发明，该工艺从二氮和氢中产生氨，因此为植物生长提供了大量廉价的氮肥。用于种植食物的氮肥绝大多数都流失到环境中，作物对氮的低效利用导致了农业土壤的过度施肥。这种农业径流导致氮肥大规模转化为一氧化二氮，这是现在第三大温室气体。基于这些考虑，氮循环对于人类在21世纪面临的粮食供应和农业、生物燃料、污染、水、环境和气候等关键挑战至关重要。Nicolai Lehnert（密歇根大学）正在组织一个研讨会，将来自许多不同领域的科学家聚集在一起，确定氮循环中的重大科学挑战，并开发跨领域的科学方法，从而可能导致解决已确定的科学挑战。特别关注的是（生物）化学对解决这些重要问题的贡献。研讨会的成果为如何推动与氮循环相关的科学知识前沿提供了一个智力路线图，重点关注具有全球意义的科学问题。讲习班的成果将通过一份简短的白皮书和一份完整的讲习班报告向科学界传播。

The Chemical Catalysis Program of the Division of Chemistry and the Environmental Engineering Program of the Chemical, Biological, Environmental and Transport Systems Division are sponsoring this workshop entitled "Feeding the World in the 21st Century: Grand Challenges in the Nitrogen Cycle " to be held on November 9-10, 2015 in Arlington, Virginia. The nitrogen cycle is one of the most significant biogeochemical cycles on Earth, as nitrogen is an essential nutrient for all forms of life. The largest reservoir of nitrogen is gaseous dinitrogen in the atmosphere; however, this form of nitrogen cannot be utilized by plants directly so access to fixed forms of nitrogen constitutes, in many cases, the most limiting factor for plant growth and food production. The second most important reservoir for nitrogen is nitrate, in the form of inorganic minerals and fertilizers, and this is the form of nitrogen that is easily assimilated by plants and microbes that live in soil and water. An important historical factor in improving agricultural crop production has been the invention of the Haber-Bosch process, which generates ammonia from dinitrogen and hydrogen, and therefore, provides abundant inexpensive access to nitrogen fertilizers for plant growth. The vast majority of total nitrogen fertilizer used to grow food is lost to the environment, and this inefficient nitrogen use by crop plants has resulted in the over fertilization of agricultural soils. This agricultural run-off results in the large-scale transformation of the nitrogen fertilizer into nitrous oxide, which is now the third most important greenhouse gas. Based on these considerations, the nitrogen cycle is of utmost importance for critical challenges that humanity is facing in the 21st century with respect to food supplies and agriculture, biofuels, pollution, water, and the environment and climate.Prof. Nicolai Lehnert (University of Michigan) is organizing a workshop to bring together scientists from many different areas to define the grand scientific challenges in the nitrogen cycle and to develop cross-cutting scientific approaches that could lead to solutions to the identified scientific challenges. A particular focus is the contributions that (bio)chemistry can make to address these important issues. The results of the workshop provide an intellectual roadmap of how to move the scientific knowledge edge related to the nitrogen cycle forward, focusing on scientific issues of global significance. The outcomes of the workshop will be disseminated to the scientific community via a short white paper and a full size workshop report.