Collaborative Research: Hierarchical Functioning of River Macrosystems in Temperate Steppes From Continental to Hydrogeomorphic Patch Scales

合作研究：温带草原河流宏观系统从大陆到水文地貌斑块尺度的层次功能

• 批准号: 1442562
• 负责人: Sudeep Chandra
• 金额: $ 71.33万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-15 至 2023-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1442562&HistoricalAwards=false
• 关键词: Collaborative; Research; Hierarchical; Functioning; River

The need to understand and manage ecosystems at larger regional to continental scale macrosystem levels is becoming increasingly crucial with global climate changes and impacts of exotic plants and animals in freshwater rivers and lakes. Macrosystem management requires an understanding of how different levels of spatial complexity (within a stream reach to entire river valley scales) and biotic organization (populations to ecosystems) affect the functioning of rivers and lakes. The present study will provide this information for 18 rivers spread equally between the two largest temperate steppe biomes of the world: the North American Great Plains and the Euro-Asian Steppes (including those in Mongolia). This project will provide research experiences for under-represented participants (particularly rural and Native American students), stimulate STEM program recruitment in largely under-represented (EPSCoR) states, support some faculty and students at primarily undergraduate institutions, and contribute to scientific education at both graduate and undergraduate institutions in two countries.These rivers flow through 3 major types of ecoregions within these temperate steppe biomes: mountain steppe shrublands, short-to-tall grasslands, and semi-arid shrublands. Scientists and students from the USA and Mongolia will sample the structure and functioning of these 18 rivers in a variety of hydrogeomorphic areas, such as constricted, meandering, braided, and anastomosing channel sections. Despite their similarity in biome and ecoregional types, the river macrosystems of the Great Plains and the Mongolian steppes vary substantially in fauna, flora, and community through ecosystem functioning. These variations result from differences in climatic patterns, the degree of riverine landscape modification (e.g., by dams, levees, and riparian modification), and the naturalness of the resident fauna. For example, most rivers in the USA contain some dams and many exotic fauna have been introduced, while the vast majority of Mongolian rivers contain no dams and their aquatic fauna is almost exclusively natural and different from those in the USA. Moreover, the Central Asian subcontinental area of Mongolia has one of the strongest warming signals on earth, with air temperatures rising three times faster than the overall northern hemisphere average. Consequently, riverine macrosystems in the USA can help predict changes to Mongolian rivers as a result of pending dam construction and possible species introductions to some rivers, while knowledge of responses of Mongolian macrosystems to more rapid climatic changes can help predict future effects in U.S. rivers. Therefore, this project's goals are to: (a) compare and contrast hierarchical scaling relationships and effects of system drivers and cross-scale interactions on rivers in similar biomes and ecoregions of the two continents; and (b) evaluate effects of climatic changes and anthropogenic disturbance to these river macrosystems.

随着全球气候变化以及淡水河流和湖泊中外来植物和动物的影响，了解和管理更大的区域到大陆尺度的宏观系统水平的生态系统变得越来越重要。宏观系统管理需要了解不同水平的空间复杂性（在一条溪流范围内达到整个河谷规模）和生物组织（种群到生态系统）如何影响河流和湖泊的功能。本研究将为世界上两个最大的温带草原生物群落（北美大平原和欧亚草原（包括蒙古的草原））之间均匀分布的 18 条河流提供这些信息。该项目将为代表性不足的参与者（特别是农村和美国原住民学生）提供研究经验，刺激代表性不足 (EPSCoR) 州的 STEM 项目招募，支持主要本科院校的一些教职员工和学生，并为两个国家的研究生和本科院校的科学教育做出贡献。这些河流流经这些温带草原生物群落内的 3 个主要类型的生态区： 山地草原灌丛、低矮到高大的草原和半干旱灌丛。来自美国和蒙古的科学家和学生将对这 18 条河流在各种水文地貌区域（例如收缩、蜿蜒、辫状和网状河道部分）的结构和功能进行采样。尽管大平原和蒙古草原的河流宏观系统在生物群落和生态区域类型上相似，但它们在动物群、植物群和生态系统功能方面存在很大差异。这些变化是由于气候模式、河流景观改造程度（例如水坝、堤坝和河岸改造）以及当地动物群的自然性的差异造成的。例如，美国的大多数河流都有一些水坝，并引入了许多外来动物群，而蒙古的绝大多数河流没有水坝，其水生动物群几乎完全是自然的，与美国的不同。此外，蒙古的中亚次大陆地区是地球上最强烈的变暖信号之一，气温上升速度是北半球整体平均气温的三倍。因此，美国的河流宏观系统可以帮助预测由于即将修建的大坝和某些河流可能引入的物种而导致的蒙古河流的变化，而了解蒙古宏观系统对更快速的气候变化的反应可以帮助预测美国河流的未来影响。因此，该项目的目标是：（a）比较和对比两大洲相似生物群落和生态区河流的层次尺度关系和系统驱动因素的影响以及跨尺度相互作用； (b) 评估气候变化和人为干扰对这些河流宏观系统的影响。

项目成果

Intercontinental analysis of temperate steppe stream food webs reveals consistent autochthonous support of fishes

• DOI: 10.1111/ele.14113
• 发表时间: 2022-10-12
• 期刊: ECOLOGY LETTERS
• 影响因子: 8.8
• 作者: Arsenault，Emily R.;Thorp，James H.;Bennadji，Hayat
• 通讯作者: Bennadji，Hayat

Macrosystems as metacoupled human and natural systems

• DOI: 10.1002/fee.2289
• 发表时间: 2021-02
• 期刊: Frontiers in Ecology and the Environment
• 影响因子: 10.3
• 作者: Flavia Tromboni;Jianguo Liu;Emanuele Ziaco;D. Breshears;Kim‐Ly Thompson;W. Dodds;K. Dahlin;E. LaRue;J. Thorp;A. Viña;M. Laguë;Alain Maasri;Hongbo Yang;S. Chandra;S. Fei

High rates of daytime river metabolism are an underestimated component of carbon cycling

白天河流的高代谢率是碳循环的一个被低估的组成部分

• DOI: 10.1038/s43247-022-00607-2
• 发表时间: 2022
• 期刊: Communications Earth & Environment
• 影响因子: 7.9
• 作者: Tromboni, Flavia;Hotchkiss, Erin R.;Schechner, Anne E.;Dodds, Walter K.;Poulson, Simon R.;Chandra, Sudeep
• 通讯作者: Chandra, Sudeep

How do methodological choices influence estimation of river metabolism?

方法选择如何影响河流代谢的估计？

• DOI: 10.1002/lom3.10451
• 发表时间: 2021
• 期刊: Limnology and Oceanography: Methods
• 作者: Schechner, Anne E.;Dodds, Walter K.;Tromboni, Flavia;Chandra, Sudeep;Maasri, Alain
• 通讯作者: Maasri, Alain

A framework for lotic macrosystem research

逻辑宏观系统研究框架

• DOI: 10.1002/ecs2.3342
• 发表时间: 2021
• 期刊: Ecosphere
• 影响因子: 2.7
• 作者: Thorp, James H.;Dodds, Walter K.;Robbins, Caleb J.;Maasri, Alain;Arsenault, Emily R.;Lutchen, Jackob A.;Tromboni, Flavia;Hayford, Barbara;Pyron, Mark;Mathews, Gregory S.
• 通讯作者: Mathews, Gregory S.