混合比率和树木大小的综合影响:混合森林如何应对气候和干旱事件?
Xiaoxia Wang1,2,3, Lulu He1,2,3, Haseen Ullah1,2,4
1State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing, China.
Frontiers in plant science
|October 25, 2024
概括
树种的混合比率显著影响森林的干旱抵御力. 最佳的混合增强了某些物种的干旱耐受性,而另一些物种在长期干旱期间可能不会从混合森林中受益.
科学领域:
- 生态生态学 生态生态学
- 林业林业 林业 林业 林业
- 适应气候变化 适应气候变化
背景情况:
- 生物多样性和生态系统功能 (BEF) 之间的关系得到了充分研究,但树种混合比对树木对气候和干旱的反应的影响基本上是未知的.
- 混合森林对于生态系统的弹性至关重要,但物种比例对气候压力下个体树木表现的具体影响需要研究.
研究的目的:
- 调查松树 (Pinus tabuliformis) 和树 (Quercus variabilis) 的不同混合比如何影响它们的气候敏感性和干旱耐受性.
- 确定树木大小和干旱持续时间对混合森林树木干旱反应的影响.
主要方法:
- 在中国,Pinus tabuliformis (P) 和Quercus variabilis (Q) 在三个混合比率 (90:10,60:40,20:80) 下建立了树环时间表.
- 评估了短期 (1993年) 和长期 (1999-2015年) 干旱下的主导,中间和抑制树木的气候敏感性和干旱耐受性指数 (弹性,耐力,恢复).
- 分析了Palmer干旱严重程度指数 (PDSI) 对不同混合比率和树木大小的树木生长和生存的影响.
主要成果:
- 在60:40 P:Q混合中,Pinus tabuliformis对前一年的PDSI敏感度增加. 干旱对短期干旱的反应在混合比率上是微不足道的.
- 在长期干旱下,Pinus tabuliformis的抵抗力,弹性和恢复能力随着Quercus variabilis比例的增加而下降. 在60:40 P:Q混合物中,Quercus variabilis表现出最高的干旱耐受性.
- 树木对PDSI的敏感性因大小类和混合比而异;主导树木在60:40和20:80混合中最敏感,而中间/被抑制树木在90:10混合中更敏感.
结论:
- 树种混合比率在温带森林中显著影响干旱敏感性和耐受性,影响因物种和干旱持续时间而异.
- Quercus variabilis受益于与Pinus tabuliformis混合,特别是以最佳比例混合,最大限度地提高其因不同水文的干旱抵御能力.
- 像Pinus tabuliformis这样具有弱竞争力的物种在长期干旱期间可能不会从混合中受益,这凸显了物种特异性特征和混合比率对可持续森林管理和气候变化适应的重要性.
相关概念视频
Responses to Drought and Flooding
10.6K
Water plays a significant role in the life cycle of plants. However, insufficient or excess of water can be detrimental and pose a serious threat to plants.
10.6K
Adaptations that Reduce Water Loss
25.1K
Though evaporation from plant leaves drives transpiration, it also results in loss of water. Because water is critical for photosynthetic reactions and other cellular processes, evolutionary pressures on plants in different environments have driven the acquisition of adaptations that reduce water loss.
25.1K
Ecological Disturbance
17.0K
An ecological disturbance is a temporary disruption in the environment resulting from abiotic, biotic, or anthropogenic factors, causing a pronounced change in an ecosystem. The impact of an ecological disturbance, which can depend on its intensity, frequency, and spatial distribution, plays a significant role in shaping the species diversity within the ecosystem.
17.0K
Responses to Heat and Cold Stress
13.4K
Every organism has an optimum temperature range within which healthy growth and physiological functioning can occur. At the ends of this range, there will be a minimum and maximum temperature that interrupt biological processes.
13.4K
Softwoods and Hardwoods
146
Softwoods and hardwoods, derived from different types of trees, are distinguished by their leaf structures and cellular compositions, each serving unique purposes in construction and manufacturing. Softwoods come from cone-bearing trees with needle-like leaves and are predominantly composed of longitudinal cells called tracheids and a smaller proportion of radial cells known as rays. Due to their cellular structure, softwoods are commonly used in construction for structural frames, sheathing,...
146
Threats to Biodiversity
22.2K
There have been five major extinction events throughout geological history, resulting in the elimination of biodiversity, followed by a rebound of species that adapted to the new conditions. In the current geological epoch, the Holocene, there is a sixth extinction event in progress. This mass extinction has been attributed to human activities and is thus provisionally called the Anthropocene. In 2019 the human population reached 7.7 billion people and is projected to comprise 10 billion by...
22.2K


