Biocomplexity in African Savannas

摘要非洲稀树草原的生物复杂性尼尔·P·哈南、罗伯特·J·斯科尔斯、迈克尔·B·考夫努尔、卢安·奥特、菲利普·尾米、格哈德·丹格尔迈尔·萨凡纳是全球重要的生态系统，对人类福利和经济具有重要意义，特别是在非洲和欧亚大陆的许多欠发达国家。在非洲，热带草原也是地球上所有生态系统中大型食草动物和食肉动物密度和多样性最大的家园。然而，定义稀树草原系统的树木和草的混合物本质上是不稳定的，与土壤类型、气候、食草动物密度和野火频率有关的多种因素被认为是导致它们共存的原因。因此，稀树草原是一个生物复杂系统，放牧强度和火灾频率等过程同时取决于和控制稀树草原结构、生产力和养分循环。我们正在发展对稀树草原生态系统的概念和数字理解，这将使人们能够通过驱动变量之间的复杂相互作用和反馈来预测稀树草原的结构和功能。这将包括在不同条件下稳定状态的变化，不同形式的稀树草原对变化的适应能力，以及稳定状态之间的阈值。该项目将进一步利用稀树大草原系统作为了解生物系统复杂性的一般模式，并开发分析方法和解释工具，以促进公众更广泛地了解环境系统之间的相互联系。

AbstractBiocomplexity in African savannasNiall P. Hanan, Robert J. Scholes, Michael B. Coughenour, Luanne Otter, Philip Omi, Gerhard DangelmayrSavannas are globally important ecosystems of great significance to human welfare and economies, especially in many less developed countries in Africa and Eurasia. In Africa, the savannas are also home to the greatest density and diversity of large herbivores and carnivores of any ecosystem on earth. However, the mixture of trees and grasses that defines savanna systems is inherently unstable and multiple factors related to soil type, climate, herbivore density, and wild-fire frequency are thought to contribute to their coexistence. Thus savannas are biocomplex systems where processes such as grazing intensity and fire frequency simultaneously depend on and control savanna structure, productivity and nutrient recycling.This project will investigate biocomplexity in the context of African savannas. We are developing the conceptual and numerical understanding of savanna ecosystems that will allow prediction of savanna structure and function resulting from the complex interactions and feedback between driving variables. This will include the change in stable states under varying conditions, the resilience of the different forms of savanna to change, and the thresholds between stable states. The project will further use savanna systems as a general model for understanding complexity in biological systems and to develop methods of analysis and interpretive tools that promote a broader public understanding of the inter-relatedness of environmental systems.