Eutrophication in aquatic ecosystems: a scientometric study

Abstract Aim: Reveal the direction for future studies about eutrophication, or even reveal the preoccupation among the scientific community about this environmental problem. With a systematic synthesis of eutrophication studies, scientists may be able to understand the state of the literature on aquatic ecosystems around the world. This study intends to identify the main factors used to control algal blooms and the eutrophication process, the countries and environments which have more research about this theme or even identify the articles’ subjects in different periods (e.g.: Experimental, theoretic, monitoring, conservation). Methods We analyzed all studies published in the Thomson ISI Web of Science on both eutrophication and phytoplankton between 2001 and 2016. Results During the period analyzed, we observed an increase in concern about this subject. Authors from institutions in the USA and China wrote most of the studies. The most important geographic and socioeconomic aspects to determine the publication number were total area and HDI respectively. However, the main determinant for the publication about this subject was international collaboration. Some of the most actual themes in ecology and conservation (e.g.: functional groups, climate change, experiment, perdition models, regional scales, invasive species) were addressed in the studies analysed. Invasive species such as Tilapia and Cylindrospermopsis raciborskii were the most cited species on these keywords. Conclusion Despite the current issues addressed in the studies on phytoplankton and eutrophication, some subjects, such as climate change or spatial pattern, were only common in years more recent. Even though studies focusing in functional diversity are highly relevant for conservation, they were not common in any year studied. The major determinant factor related to the increasing in eutrophication knowledge was the international collaboration

# 研究目的
本研究旨在为富营养化领域的未来研究指明方向，同时厘清科学界对这一环境问题的核心关切。通过对富营养化相关研究开展系统性综合分析，科研人员可全面掌握全球水生生态系统领域的研究现状。本研究拟明确调控藻华与富营养化过程的核心影响因素，梳理该主题研究较为集中的国家与研究场景，同时识别不同时期的文章研究主题（如实验类、理论类、监测类、保护类研究）。
# 研究方法
本研究分析了2001年至2016年间发表于汤森ISI Web of Science数据库（Thomson ISI Web of Science）中，与富营养化及浮游植物相关的全部已发表研究成果。
# 研究结果
在所分析的时间段内，学界对该主题的关注度呈显著上升趋势。美国与中国科研机构的作者贡献了绝大多数相关研究成果。影响发文量的核心地理与社会经济因素分别为区域总面积与人类发展指数（HDI, Human Development Index）。然而，推动该主题发文量增长的最关键因素为国际科研合作。本研究纳入的文献覆盖了生态学与保护生物学领域的诸多前沿主题，例如功能类群、气候变化、实验研究、预测模型、区域尺度研究、入侵物种等。关键词中被引频次最高的入侵物种为罗非鱼（Tilapia）与柱孢鱼腥藻（Cylindrospermopsis raciborskii）。
# 研究结论
尽管当前浮游植物与富营养化相关研究已覆盖诸多热点问题，但气候变化、空间格局等主题仅在近年才成为研究主流。尽管聚焦功能多样性的研究对生态保护具有极高的科学价值，但在本次分析覆盖的所有年份中，此类研究均较为少见。推动富营养化研究认知水平持续提升的核心驱动因素，仍是国际科研合作。