Biodiversity dynamics across environmental gradients and under impending environmental change

跨环境梯度和即将发生的环境变化的生物多样性动态

• 批准号: 2874746
• 金额: --
• 依托单位: University of Birmingham
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2874746
• 关键词: Biodiversity; dynamics; across; environmental; gradients

We live in a time of radical changes and rapid biodiversity loss. To make better predictions of the impacts of anthropogenic change on the world's declining biodiversity, it is crucial to first understand how species are naturally distributed and then assess how their distribution might shift or, worse, disappear. Biodiversity is unequally distributed across the Earth, increasing towards low latitudes, low to intermediate elevations, and intermediate canopy heights within forests. These spatial gradients reflect differences in environmental variables, such as luminosity, temperature and humidity, which affect physiological, demographic, and biotic interaction processes. Species show different preferences for these variables (i.e. ecological niche), which causes biodiversity to peak in areas of high niche overlap, provided that coexistence mechanisms are at play. Both niche-related variables and coexistence mechanisms are being disrupted by humans. Because many environmental variables naturally co-vary, contrasting gradients should provide insights to disentangle their roles in biodiversity dynamics under a changing world. Therefore, this project takes advantage of 1) novel mechanistic models than can simulate contrasting environmental gradients and 2) a biological system of major ecological importance - vascular epiphytes. Vascular epiphytes, including most orchids and bromeliads, are plants growing non-parasitically on trees. They are key to nutrient cycles and interaction networks in tropical forests, accounting for 10% of world's flora and up to 50% of some local floras. They vary in how they are distributed along vertical and elevational gradients, probably following their temperature and humidity preferences and often being geographically restricted (i.e. endemic and threatened). Epiphytes have been understudied due to difficulties in sampling the forest canopy despite being particularly vulnerable to deforestation and global warming. Hence, simulation experiments are ideal to improve our ecological understanding of the system while also to i) identify the data collection that should be prioritized in empirical studies and ii) explore scenarios of human impacts without manipulating vulnerable biodiversity.

我们生活在一个剧烈变化和生物多样性迅速丧失的时代。为了更好地预测人为变化对世界生物多样性下降的影响，至关重要的是首先了解物种是如何自然分布的，然后评估它们的分布可能如何变化，或更糟糕的是消失。生物多样性在地球上分布不均，向低纬度、低至中海拔和森林内的中等树冠高度增加。这些空间梯度反映了环境变量的差异，例如光度、温度和湿度，这些变量影响生理、人口和生物相互作用过程。物种对这些变量（即生态位）表现出不同的偏好，这导致生物多样性在高生态位重叠的区域达到顶峰，前提是共存机制发挥作用。生态位相关变量和共存机制都被人类破坏。由于许多环境变量自然地共同变化，对比梯度应该提供见解，以理清它们在不断变化的世界下的生物多样性动态中的作用。因此，该项目利用了 1）可以模拟对比环境梯度的新颖机制模型和 2）具有重大生态重要性的生物系统 - 维管附生植物。维管束附生植物，包括大多数兰花和凤梨科植物，是非寄生在树上生长的植物。它们是热带森林养分循环和相互作用网络的关键，占世界植物群的 10%，占一些当地植物群的 50%。它们沿垂直和海拔梯度的分布方式各不相同，可能遵循其温度和湿度偏好，并且通常受到地理限制（即地方性和受威胁）。尽管附生植物特别容易受到森林砍伐和全球变暖的影响，但由于对森林冠层采样的困难，人们对附生植物的研究还不够充分。因此，模拟实验非常适合提高我们对系统的生态理解，同时也可以 i）确定实证研究中应优先考虑的数据收集，以及 ii）在不操纵脆弱生物多样性的情况下探索人类影响的情景。