LTREB: Long-term ecosystem responses to directional changes in precipitation amount and variability in an arid grassland

LTREB：干旱草原降水量和变异性方向变化的长期生态系统响应

• 批准号: 1754106
• 负责人: Osvaldo Sala
• 金额: $ 52万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1754106&HistoricalAwards=false
• 关键词: LTREB; Long; term; ecosystem; responses

In the American Southwest, rainfall patterns are changing, and are likely to continue to change in the coming decades. Major droughts and floods will occur more often and will be more intense. These changes are likely to have a large impact on grasslands and the ecosystem services they provide. Scientists have studied grassland ecosystems and the plant species that live in them for many years. Predicting the future of grasslands as the environment changes remains a challenge, however, because it is very difficult to understand causes of patterns using observations alone. Controlled experiments can uncover what causes changes in grasslands with enough confidence to predict their future as they begin to experience conditions never seen before. It is also difficult to predict long-term changes using only short-term experiments. This project will expand on decade-long field experiments in which rainfall amount and variability were manipulated to learn how grassland ecosystems are likely to change. Results from these experiments will yield new understanding that will provide guidance to managers of drylands in the Southwest United States, and around the world. This project will also train a new generation of scientists, many of whom are members of underrepresented minority groups.This project is guided by two hypotheses about endogenous and exogenous phenomena that interact with each other to generate dryland responses to changes in amount and variability of precipitation. (1) Endogenous biogeochemical and demographic phenomena mediate abrupt or continuous changes in populations, communities and ecosystem processes. (2) Exogenous phenomena, such as El Niño events that occur with low frequency, interact with endogenous mechanisms to affect system resilience, leading to changes in population dynamics and ecosystem processes. This project will capture the impacts of infrequent exogenous phenomena and the cumulative effects of endogenous factors on populations of desert species, communities and ecosystems. The project will build upon two extant experiments located in a Desert Grassland in New Mexico: (a) manipulation of rainfall amount (80% reduced precipitation, ambient, 80% increased) crossed with changes in nitrogen availability, and (b) manipulation of rainfall variability (control, enhanced variability by 50% and 80%). Long-term manipulations of precipitation amount are accomplished using rainout shelters coupled with irrigation systems. Different levels of nitrogen availability are achieved via fertilization. Manipulations of precipitation variability are conducted by flipping drought and irrigation treatments from year to year in the same plots. Response variables include above and belowground net primary production, species composition, net nitrogen mineralization and leaf nitrogen isotopic ratios. This research has the potential to transform understanding of long-term ecosystem responses to changes in patterns of precipitation, which is critical to assessment of how ecosystem services are likely to change over the coming decades.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在美国西南部，降雨模式正在发生变化，并且在未来几十年内可能会继续发生变化，这些变化可能会对草原和生态系统产生重大影响。然而，科学家们对草原生态系统和生活在其中的植物物种进行了多年研究，预测草原随着环境变化的未来仍然是一个挑战，因为仅凭观察很难理解模式的原因。对照实验可以揭示原因当草原开始经历前所未有的条件时，我们有足够的信心预测它们的未来。仅使用短期实验来预测长期变化也很困难，该项目将扩展长达十年的实地实验，其中降雨。这些实验的结果将产生新的认识，为美国西南部和世界各地的旱地管理者提供指导。科学家，其中许多是代表性不足的成员该项目以关于内源性和外源性现象的两个假设为指导，这些现象相互作用，产生旱地对降水量和变率变化的反应（1）内源性生物地球化学和人口现象介导人口、社区的突然或持续变化。 (2) 外生现象，如发生频率较低的厄尔尼诺事件，与内生机制相互作用，影响系统复原力，导致种群动态和生态系统过程的变化。内源因素对沙漠物种、群落和生态系统种群的累积影响 该项目将建立在新墨西哥州沙漠草原上的两个现有实验的基础上：(a) 控制降雨量（减少 80% 的降雨量，减少 80% 的环境降雨量）。增加）与氮可用性的变化交叉，以及（b）降雨变异性的控制（控制，变异性增加 50% 和 80%）是通过使用防雨棚和不同水平的灌溉系统来实现的。氮肥利用率通过施肥控制降水变化是通过在同一块土地上逐年翻转干旱和灌溉处理来实现的，响应变量包括地上和地下净初级生产力、物种组成、净氮矿化和叶片氮同位素比率。有潜力改变对长期生态系统对降水模式变化的反应的理解，这对于评估未来几十年生态系统服务可能发生的变化至关重要。该奖项反映了 NSF 的法定使命，并被认为值得支持通过使用基金会的智力价值和更广泛的影响审查标准进行评估。

项目成果

Changes in belowground biodiversity during ecosystem development

• DOI: 10.1073/pnas.1818400116
• 发表时间: 2019-03-15
• 期刊: Proceedings of the National Academy of Sciences
• 作者: M. Delgado‐Baquerizo;R. Bardgett;P. Vitousek;F. Maestre;Mark A. Williams;D. Eldridge;H. Lambers;S. Neuhauser;A. Gallardo;Laura García;O. Sala;S. Abades;F. Alfaro;A. Berhe;M. Bowker;Courtney M. Currier;N. Cutler;S. Hart;P. Hayes;Z. Hseu;M. Kirchmair;Víctor M. Peña;Cecilia A. Pérez;S. Reed;F. Santos;C. Siebe;B. Sullivan;Luis Weber;N. Fierer
• 通讯作者: N. Fierer

Sensitivity of primary production to precipitation across the United States

美国初级生产对降水的敏感性

• DOI: 10.1111/ele.13455
• 发表时间: 2020-01
• 期刊: Ecology Letters
• 影响因子: 8.8
• 作者: Maurer, Gregory E.;Hallmark, Alesia J.;Brown, Renée F.;Sala, Osvaldo E.;Collins, Scott L.;Coulson, ed., Tim
• 通讯作者: Coulson, ed., Tim

Global change effects on plant communities are magnified by time and the number of global change factors imposed

全球变化对植物群落的影响随着时间和施加的全球变化因素的数量而放大

• DOI: 10.1073/pnas.1819027116
• 发表时间: 2019-08-19
• 期刊: Proceedings of the National Academy of Sciences
• 作者: K. Komatsu;Meghan L. Avolio;N. Lemoine;F. Isbell;Emily Grman;G. Houseman;S. Koerner;D. S. Johnson;Kevin R Wilcox;J. Alatalo;J. Anderson;R. Aerts;S. Baer;A. Baldwin;J. Bates;C. Beierkuhnlein;R. T. Belote;J. Blair;J. Bloor;P. Bohlen;E. Bork;E. Boughton;W. Bowman;A. Britton;J. Cahill;E. Chaneton;N. Chiariello;Jimin Cheng;S. Collins;J. Cornelissen;G. Du;A. Eskelinen;J. Firn;B. Foster;L. Gough;K. Gross;L. Hallett;Xingguo Han;H. Harmens;M. Hovenden;A. Jagerbr;A. Jentsch;C. Kern;K. Kl;erud;erud;A. Knapp;J. Kreyling;Wei Li;Yiqi Luo;R. McCulley;Jennie R. McLaren;J. Megonigal;J. Morgan;V. Onipchenko;S. Pennings;J. Prevéy;J. Price;P. Reich;C. Robinson;F. Russell;O. Sala;E. Seabloom;Melinda D. Smith;Nadejda A. Soudzilovskaia;Lara Souza;K. Suding;K. B. Suttle;T. Svejcar;D. Tilman;P. Tognetti;R. Turkington;S. White;Zhuwen Xu;L. Yahdjian;Qiang Yu;Pengfei Zhang;Yunhai Zhang
• 通讯作者: Yunhai Zhang

Grazing and ecosystem service delivery in global drylands

全球旱地的放牧和生态系统服务提供

• DOI: 10.1126/science.abq4062
• 发表时间: 2022-11-25
• 期刊: Science
• 影响因子: 56.9
• 作者: F. Maestre;Yoann Le Bagousse;M. Delgado‐Baquerizo;D. Eldridge;H. Saiz;M. Berdugo;Beatriz Gozalo;V. Ochoa;Emilio Guirado;M. García;Enrique Valencia;J. Gaitán;Sergio Asensio;B. Mendoza;C. Plaza;Paloma Díaz;A. Rey;Hangwei Hu;Ji‐Zheng He;Juntao Wang;A. Lehmann;M. Rillig;Simone Cesarz;N. Eisenhauer;J. Martínez;E. Moreno‐Jiménez;O. Sala;M. Abedi;N. Ahmadian;C. Alados;Valeria Aramayo;F. Amghar;Tulio Arredondo;Rodrigo J. Ahumada;Khadijeh Bahalkeh;F. Ben Salem;N. Blaum;B. Boldgiv;M. Bowker;Donaldo Bran;Chongfeng Bu;Rafaella Canessa;Andrea P. Castillo;Helena Castro;Ignacio Castro;Patricio Castro;Roukaya Chibani;A. A. Conceição;Courtney M. Currier;A. Darrouzet‐Nardi;B. Deák;D. Donoso;A. Dougill;J. Durán;Batdelger Erdenetsetseg;C. Espinosa;A. Fajardo;M. Farzam;D. Ferrante;Anke S. K. Frank;L. Fraser;L. Gherardi;Aaron C. Greenville;Carlos A. Guerra;Elizabeth Gusmán;R. M. Hernández;N. Hölzel;E. Huber;F. M. Hughes;Oswaldo Jadán;F. Jeltsch;A. Jentsch;K. Kaseke;Melanie Köbel;J. Koopman;C. Leder;A. Linstädter;P. L. le Roux;Xinkai Li;P. Liancourt;Jushan Liu;M. A. Louw;G. Maggs;T. Makhalanyane;O. Issa;A. Manzaneda;E. Marais;Juan P. Mora;G. Moreno;S. Munson;Alice Nunes;G. Oliva;Gastón R. Oñatibia;Guadalupe Peter;M. O. Pivari;Y. Pueyo;R. Quiroga;Soroor Rahmanian;S. Reed;P. Rey;B. Richard;Ale;ra Rodríguez;ra;V. Rolo;Juan G. Rubalcaba;J. Ruppert;Ayman Salah;Max A. Schuchardt;Sedona Spann;I. Stavi;Colton Stephens;A. Swemmer;A. Teixido;A. Thomas;H. Throop;K. Tielbörger;S. Travers;J. Val;O. Valkó;Liesbeth van den Brink;S. Ayuso;Frederike Velbert;W. Wamiti;Deli Wang;Lixin Wang;G. Wardle;L. Yahdjian;E. Zaady;Yuanming Zhang;Xiaobing Zhou;B. Singh;N. Gross
• 通讯作者: N. Gross

Effect of interannual precipitation variability on dryland productivity: A global synthesis

年际降水量变化对旱地生产力的影响：全球综合

• DOI: 10.1111/gcb.14480
• 发表时间: 2018-11-22
• 期刊: Global Change Biology
• 影响因子: 11.6
• 作者: L. Gherardi;O. Sala
• 通讯作者: O. Sala