EAGER: Spatial patterns of nutrient limitation and carbon storage in South African coastal lowland landscapes

从地理上讲，非洲是了解陆地-大气碳交换的最薄弱环节之一。本研究的目的是：(1)采用一种新颖的实验设计来确定养分有效性的变化如何决定草地碳生产力的空间格局；(2)首次量化南非东南沿海两个优先自然保护区内沿海和沙丘林的碳储量。对比每个保护区内的火灾和植被模式，将有助于在景观尺度上发展关于非洲碳储量的新的火山地理学观点。通过研究南非沿海优先保护区的碳储量，本研究将加深对非洲景观在保护管理和全球生态系统科学中的作用的理解。目前缺乏对火灾、气候和营养循环之间复杂相互作用的理解，阻碍了生态系统对气候变化响应的大规模建模。这一问题对非洲来说尤其严重，因为非洲是最大的火碳排放源，而且对其碳储量的估计很少。直接测量新地点的碳储量并确定其在多个尺度上的限制因素，正如本项目所探索的那样，对未来诊断建模工作的发展至关重要。了解火和土壤养分如何控制这些模式将有助于该地区和全球的景观和保护管理。这项研究也将有助于培养国际合作科学的研究生，这是国家教育的一个关键优先事项。

Geographically, Africa is one of the weakest links in understanding land-atmosphere carbon exchange. The objectives of this research are to (1) employ a novel experimental design to determine how variation in nutrient availability determines spatial patterns in grassland carbon productivity and (2) provide the first-ever quantification of carbon storage in coastal and dune forests within two priority nature reserves in the southeastern coast of South Africa. Contrasting fire and vegetation patterns within each reserve will allow for the development of new pyrogeographic perspectives on African carbon storage at landscape scales. By studying carbon storage in priority conservation areas in coastal South Africa, this research will establish a deeper understanding of the role of African landscapes in conservation management and global ecosystem science. A current lack of understanding of complex interactions among fire, climate, and nutrient cycling hinders broad-scale modeling of ecosystem response to climate change. This issue is particularly acute for Africa, which represents the largest source of fire-derived carbon emissions and for which carbon storage estimates are scarce. Direct measurement of carbon storage in new locations and identification of its limiting factors across multiple scales, as explored in this project, are critical for the development of future diagnostic modeling efforts. Understanding how fire and soil nutrients govern these patterns will contribute to landscape and conservation management in the region and globally. This research will also contribute to the training of graduate students in collaborative international science which is a key national educational priority.