Global crop yield response to extreme heat stress under multiple climate change futures
Global crop yield response to extreme heat stress under multiple climate change futures
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DOI：
10.1088/1748-9326/9/3/034011
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发表时间：
2014-03-01
影响因子：
6.7
通讯作者：
Warren, Rachel
中科院分区：
文献类型：
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作者：
Deryng, Delphine;Conway, Declan;Warren, Rachel
作物生殖期的极端热胁迫对作物生产力至关重要。预计极端气候事件的频率和严重程度的变化将对作物产量和全球粮食生产产生不利影响。本研究应用全球作物模式PEGASUS首次在全球范围内量化了21世纪世纪72种气候变化情景下极端高温胁迫对玉米、春小麦和大豆产量的影响。我们的研究结果表明，在一系列RCP下，玉米将面临越来越严重的影响，但由于CO2施肥效应，春小麦和大豆将在全球范围内改善到21世纪80年代，尽管部分热带和亚热带地区可能面临大幅减产。我们发现，到21世纪80年代，在RCP 8.5下，考虑到CO2施肥效应，全球玉米产量损失可能会增加一倍（Δ Y = -12.8 +/- 6.7% vs-7.0 +/- 5.3%，无HSA），将春小麦产量预期收益减半（Δ Y = 34.3 +/- 13.5%，不含HSA时为72.0 +/- 10.9%），大豆产量提高四分之一（Δ Y= 15.3 +/- 26.5%，不含HSA时为20.4 +/- 22.1%）。该范围反映了由于气候模型情景之间的差异而产生的不确定性;大豆表现出积极和消极的影响，玉米一般是消极的，春小麦一般是积极的。此外，当假设CO2施肥效应可以忽略不计时，我们观察到RCP 2.6中的激进气候减缓政策可以避免超过RCP 8.5下预计到21世纪80年代的全球平均产量损失的80%。我们发现，不同地区的气候影响存在很大差异，极端热应力对主要产区和低收入国家产生了不利影响。
Extreme heat stress during the crop reproductive period can be critical for crop productivity. Projected changes in the frequency and severity of extreme climatic events are expected to negatively impact crop yields and global food production. This study applies the global crop model PEGASUS to quantify, for the first time at the global scale, impacts of extreme heat stress on maize, spring wheat and soybean yields resulting from 72 climate change scenarios for the 21st century. Our results project maize to face progressively worse impacts under a range of RCPs but spring wheat and soybean to improve globally through to the 2080s due to CO2 fertilization effects, even though parts of the tropic and sub-tropic regions could face substantial yield declines. We find extreme heat stress at anthesis (HSA) by the 2080s (relative to the 1980s) under RCP 8.5, taking into account CO2 fertilization effects, could double global losses of maize yield (Delta Y = -12.8 +/- 6.7% versus -7.0 +/- 5.3% without HSA), reduce projected gains in spring wheat yield by half (Delta Y = 34.3 +/- 13.5% versus 72.0 +/- 10.9% wwithout HSA) and in soybean yield by a quarter (Delta Y= 15.3 +/- 26.5% versus 20.4 +/- 22.1% without HSA). The range reflects uncertainty due to differences between climate model scenarios; soybean exhibits both positive and negative impacts, maize is generally negative and spring wheat generally positive. Furthermore, when assuming CO2 fertilization effects to be negligible, we observe drastic climate mitigation policy as in RCP 2.6 could avoid more than 80% of the global average yield losses otherwise expected by the 2080s under RCP 8.5. We show large disparities in climate impacts across regions and find extreme heat stress adversely affects major producing regions and lower income countries.