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在LPJmL植被模型中,降雨季节性主导了亚马逊森林的临界降水值
Da Nian1, Sebastian Bathiany2, Boris Sakschewski1
1Potsdam Institute for Climate Impact Research, 14473 Potsdam, Germany.
The Science of the total environment
|July 3, 2024
概括
亚马逊雨林显示了与平均年降水 (MAP) 相关的地表生物质 (AGB) 的关键临界点. 接近这一门信号加快森林衰退,一些地区已经面临风险.
科学领域:
- 生态生态学 生态生态学
- 气候科学 气候科学
- 林业林业 林业 林业 林业
背景情况:
- 亚马逊热带雨林对气候变化和森林砍伐的敏感性需要了解其对降雨转移的反应.
- 使用动态全球植被模型 (DGVM) 的现有研究经常将场景限制在社会经济上可信的途径上.
研究的目的:
- 模拟亚马逊森林对理想降水变化的反应,使用最先进的DGVM.
- 为了确定关键降水值和植物生物量下降的警告信号.
主要方法:
- 应用LPJmL DGVM来模拟亚马逊森林动态在线性下降和增加降水场景下.
- 分析地表生物质 (AGB) 与平均年降水量 (MAP) 之间的关系,包括关键减速指标.
主要成果:
- 确定了AGB和MAP之间的非线性,可逆关系,其中有一个临界值,低于这个值,生物质减少会加速.
- 观察到临界减速是加速生物质损失的潜在早期预警信号.
- 临界降水值因地区而异,在亚马逊西北部最低,东部和南部地区可能已经低于其值.
结论:
- 降水季节性和潜在蒸发透气 (PET) 是决定临界降水值的关键因素.
- 虽然火灾的影响最小,但根深蒂固的适应可以降低某些地区的门.
- 该研究强调了由于水循环变化而导致亚马逊森林退化的风险,以及在现有水供应量较高的地区对干旱的脆弱性增加.
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