Biocomplexity in African Savannas

非洲稀树草原的生物复杂性：Niall P. Hanan，Robert J. Scholes，Michael B. Coughenour，Luanne Otter，Philip Omi，Gerhard Dangelmayr Savannas是全球重要的生态系统，对人类福祉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，大草原也是地球上任何生态系统中大型食草动物和食肉动物密度最大、种类最多的家园。 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有助于它们的共存。因此，稀树草原是生物复合系统，其中放牧强度和火灾频率等过程同时取决于并控制稀树草原的结构、生产力和养分循环。我们正在开发的稀树草原生态系统的概念和数值的理解，这将使稀树草原的结构和功能的预测，从驱动变量之间的复杂的相互作用和反馈。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变化的弹性，以及稳定状态之间的阈值。该项目将进一步利用稀树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，促进公众更广泛地了解环境系统的相互关联性。

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.