U.S.-Vietnam Planning Visit: Collaborative Research on Nutrient Cycling and Productivity in the South China Sea

OISE-0746714（蒙托亚，佐治亚理工学院）美国美国乔治亚理工学院生物系的Joseph Montoya教授将与越南芽庄海洋研究所的Nguyen Ngoc Lam博士和胡志明市越南国立大学海洋、气象和水文学系主任La Thi ang教授进行计划访问。他们的目标是建立一个合作项目，研究南海固氮生物（重氮营养体）的分布、活性和多样性。氮是一种重要的植物营养物质，在限制许多海洋生态系统的初级生产中起着关键作用。海水中最丰富的氮形式是N2，它只能被固氮生物（重氮营养体）用作生长的基质。最近的生物和生物地球化学研究表明，在不同的热带和亚热带水域，固氮在数量上是重要的，有时是主要的，支持生物生产的新N来源。然而，重氮营养生物的多样性、它们的活性率和控制氮固定的因素仍然知之甚少。南中国海是一个经济上重要的水域，拥有重要但受到严重压力的渔业和重要的矿产资源。海洋很小，人类对土地和水的利用变化可以通过河流系统传播，并在短时间内对海洋特性产生影响。一项有针对性的合作实地研究将为我们了解这一重要边缘海域的营养动态和生态系统对陆源强迫的响应做出重要贡献，并将为评估未来土地利用变化对养分循环的响应提供重要基准。佐治亚理工学院和越南研究机构的研究人员之间有足够的兴趣重叠，表明他们可以成功地开展所提议的活动，而且这种互动将使双方受益。该访问还将为一名博士后、一名研究生和一名本科生提供支持。这种全球研究经验可能会为他们在整个研究生涯中提供许多与越南同事继续接触的机会。

OISE-0746714 (Montoya, Georgia Institute of Technology)U.S.-Vietnam Planning Visit: Collaborative Research on Nutrient Cycling and Productivity in the South China SeaABSTRACTThis award supports a planning visit to enable Professor Joseph Montoya in the Biology Department at the Georgia Institute of Technology to meet with Dr. Nguyen Ngoc Lam at the Institute of Oceanography in Nha Trang and Professor La Thi Cang, Head of the Department of Oceanology, Meteorology, and Hydrology at the Vietnam National University in Ho Chi Minh City. Their goal is to establish a collaborative project to study the distribution, activity, and diversity of N2 fixing organisms (diazotrophs) in the South China Sea. Nitrogen is an essential plant nutrient and plays a critical role in limiting primary production in many marine ecosystems. The most abundant form of nitrogen present in seawater is N2, which can be used as a substrate for growth only by N2 fixing organisms (diazotrophs). Recently biological and biogeochemical studies have demonstrated that N2 fixation is a quantitatively important, and at times the dominant, source of new N supporting biological production in diverse tropical and subtropical waters. Nevertheless, the diversity of diazotrophic organisms, their rates of activity, and the factors controlling N2 fixation all remain poorly understood. The South China Sea is an economically important water body, containing important but severely stressed fisheries as well as significant mineral resources. The Sea is small enough that anthropogenic changes in land and water use can propagate through the river system and have an impact on oceanic properties on short time scales. A focused, collaborative field study will make an important contribution to our understanding of nutrient dynamics and ecosystem response to terrigenous forcings in this important marginal sea, and will provide an important benchmark for evaluating future changes in nutrient cycling in response to land use changes. There is sufficient overlap of interests between researchers at Georgia Tech and the Vietnamese Institutions to indicate that they can successfully pursue the activities proposed, and that the interaction will benefit both sides. The visit will also provide support for a postdoc, a graduate student and an undergraduate student. This global research experience will likely provide them many opportunities for continuing contacts with their Vietnamese colleagues throughout their research careers.