Towards a Comprehensive Understanding of Changes in the Amazon Hydrological Cycle

全面了解亚马逊水文循环的变化

• 批准号: NE/M02203X/1
• 负责人: Roel Brienen
• 金额: $ 8.53万
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2015
• 资助国家: 英国
• 起止时间: 2015 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FM02203X%2F1
• 关键词: Towards; Comprehensive; Understanding; Changes; Amazon

Over the last decade the Amazon Basin has experienced extreme events of flooding (2009, 2012-2014) and droughts (2005, 2010). These events have had strong impacts not only on the Amazon forest, but also on its people and economy. How the climate of the Amazon will develop in the future remains uncertain however, as the accuracy of future climate model predictions for the Amazon is low, and as data on past natural climate/hydrology variability cover only a short period. The proposed research partnership will be used to obtain a better understanding of long-term variability of past dry season length and precipitation intensity, and its climatic controls. This will be done by analyzing ring widths and oxygen isotopic ratios in tree rings from existing and new wood samples from floodplain trees in the Amazon. Ring width from floodplain trees will be used to reconstruct the length of the non-flooded phase, while we will use oxygen isotopes in tree rings (d18O) as a proxy for dry season precipitation d18O. We will carry out sampling at two sites located in two sub-basins, the central region (Solimões River) and the northern sub-basin (Negro River) to provide a long-term perspective on the recent changes by revealing long time series of oxygen isotopes in the floodplain species Macrolobium acaciifolium, extending back more than 150-300 years. This will allow unraveling natural cycles from anthropogenic influences and thus allow us to predict what to expect for the future. Such predictions are of paramount importance to the people and economy of Brazil. If natural cycles explain the recent extreme events, one could expect a decrease again of these extremes in the near future. If the recent extremes are rather due to large-scale shifts in the climate system due to eg. warming of the sea surface temperatures globally, then we may expect more extreme event in the immediate future. By looking back for over 300 years, we will be able to unravel natural cycles from man-made warming. Within the current active NERC grant (NE/K01353X/1) we are using Earth system models to help in the interpretation of the recent changes. An integral component of this proposed partnership is the joint organisation of an "international tree ring and isotope workshop" in Brazil at INPA. The objective of this workshop is to: a) Gather international researchers and students working on this and similar topics, b) Identify research needs in the field and brainstorm ideas to come up with concrete research directions for the next years, c) Capacitate (mainly) Brazilian researchers and students in existing and new techniques and developments in the field.

在过去的十年里，亚马逊流域经历了洪水（2009年、2012年至2014年）和干旱（2005年、2010年）的极端事件。这些事件不仅对亚马逊森林产生了强烈影响，而且对其人民和经济也产生了强烈影响。然而，由于未来气候模式对亚马逊地区预测的准确性很低，而且过去自然气候/水文变率的数据只覆盖很短的时期，因此亚马逊地区未来的气候将如何发展仍不确定。拟议的研究伙伴关系将用于更好地了解过去旱季长度和降水强度的长期变化及其气候控制。这将通过分析来自亚马逊洪泛区树木的现有和新木材样本的年轮宽度和氧同位素比率来完成。洪泛区树木的年轮宽度将用于重建非淹水期的长度，而我们将使用树木年轮中的氧同位素（d18O）作为旱季降水d18O的代表。我们将在位于中部（Solimões河）和北部（Negro河）两个子流域的两个地点进行采样，通过揭示冲积平原物种巨叶藻（Macrolobium acaciifolium）的长时间序列氧同位素，提供近期变化的长期视角，这些变化可以追溯到150-300多年前。这将使我们能够从人为影响中揭示自然周期，从而使我们能够预测未来的情况。这样的预测对巴西的人民和经济至关重要。如果自然循环可以解释最近的极端事件，人们可以预期在不久的将来这些极端事件会再次减少。如果最近的极端天气是由于气候系统的大规模变化，例如。全球海洋表面温度变暖，那么我们可能会在不久的将来看到更多的极端事件。通过回顾过去300多年，我们将能够解开人为变暖带来的自然循环。在当前有效的NERC拨款（NE/K01353X/1）中，我们正在使用地球系统模型来帮助解释最近的变化。这一拟议的伙伴关系的一个组成部分是在巴西国家海洋局联合组织一个“国际树木年轮和同位素讲习班”。本次研讨会的目的是：a)聚集从事该领域和类似主题的国际研究人员和学生，b)确定该领域的研究需求，并集思广益，为未来几年提出具体的研究方向，c)培养（主要是）巴西研究人员和学生在该领域的现有和新技术和发展。

项目成果

Contrasting controls on tree ring isotope variation for Amazon floodplain and terra firme trees.

亚马逊洪泛区和陆地树木年轮同位素变化的对比控制。

• DOI: 10.1093/treephys/tpz009
• 发表时间: 2019
• 期刊: Tree physiology
• 影响因子: 4
• 作者: Barçante Ladvocat Cintra B

Oxygen isotopes in tree rings show good coherence between species and sites in Bolivia

• DOI: 10.1016/j.gloplacha.2015.09.008
• 发表时间: 2015-10-01
• 期刊: GLOBAL AND PLANETARY CHANGE
• 影响因子: 3.9
• 作者: Baker, Jessica C. A.;Hunt, Sarah F. P.;Brienen, Roel J. W.
• 通讯作者: Brienen, Roel J. W.

Tree demography dominates long-term growth trends inferred from tree rings.

• DOI: 10.1111/gcb.13410
• 发表时间: 2017-03
• 期刊: Global change biology
• 影响因子: 11.6
• 作者: Brienen RJ;Gloor M;Ziv G
• 通讯作者: Ziv G

A response to 'Trends in tropical tree growth: reanalysis confirms earlier findings'.

对“热带树木生长趋势：重新分析证实了早期发现”的回应。

• DOI: 10.1111/gcb.13605
• 发表时间: 2017
• 期刊: Global change biology
• 影响因子: 11.6
• 作者: Brienen RJ

Paired analysis of tree ring width and carbon isotopes indicates when controls on tropical tree growth change from light to water limitations.

• DOI: 10.1093/treephys/tpab142
• 发表时间: 2022-06-09
• 期刊: Tree physiology
• 影响因子: 4