ETBC Collaborative Research: Soil thresholds and process domains: controls, distribution, and implications

土壤的肥力差别很大，因此适合集约农业，特别是传统和低投入形式的集约农业。尽管影响土壤肥力的因素（例如降雨和土壤年龄）在逐渐和持续地变化，但土壤肥力以及与之相关的一系列土壤性质和过程往往在空间上突然变化。本研究模拟了土壤突变的原因并评估了其后果，并探讨了它们对自然和农业条件下陆地生态系统功能的影响。它建立在夏威夷群岛土壤的广泛数据库的基础上，其中包括控制土壤的因素的巨大差异（例如，降雨量从200毫米/年到4000毫米/年，土壤年龄从几百年到几百万年）；这个数据库包括土壤性质和过程中阈值的非常清楚的例子。此外，它还详细分析了在与欧洲人接触之前夏威夷农业的分布和动态。建模工作将在土壤发育过程的基本模型和这些详细信息之间进行迭代，试图确定需要多少细节来模拟土壤突变的发展以及它们之间土壤性质相对一致的区域。它将用夏威夷接触前农业系统内及其周围新收集的土壤信息，以及新西兰由不同类型岩石形成的土壤，来测试这些模型。该项目将提供关于土壤肥力背后的过程的基本信息，以及它们如何在过去塑造集约化农业系统的分布（并可能有助于今天和未来的低投入系统）。开展这项研究需要整合生态学、土壤学、水文学、地球化学和人类学的信息；因此，它将有助于不同学科的概念和实践的统一。将资助两名博士后和几名本科生。这些学生和博士后将学习如何整合广泛的研究领域。最后，这个项目与夏威夷土著组织和机构正在进行的努力密切相关，以了解和恢复夏威夷传统的接触前农业系统。为了教育和文化目的，也为了了解这些系统对现在和未来农业可持续性的贡献。该项目将为这些努力带来科学的组成部分，从而为教授和学习与文化和修复工作相结合的科学提供机会。

Soils differ substantially in fertility and hence in their suitability for intensive agriculture - especially traditional and low-input forms of intensive agriculture. Often soil fertility and the suite of soil properties and processes that are associated with it change abruptly in space, despite gradual and continuous changes in the factors that influence soil fertility (for example rainfall and soil age). This research models the causes and evaluates the consequences of abrupt changes in soils, and explores their implications for the functioning of terrestrial ecosystems under both natural and agricultural conditions. It builds on an extensive data base of soils from the Hawaiian Islands that includes large differences in the factors that control soils (for example rainfall from 200 mm/yr to 4000 mm/yr, soil age from a few hundred to several million years); this data base includes very clear examples of thresholds in soil properties and processes. In addition, it draws upon a detailed analysis of the distribution and dynamics of Hawaiian agriculture prior to European contact. The modeling effort will iterate between fundamental models of soil developmental processes and this detailed information, seeking to determine how much detail is necessary to model the development of abrupt changes in soils and the regions between them where soil properties are relatively consistent. It will test those models with newly collected soils information in and around pre-contact agricultural systems in Hawaii, and on soils formed from different types of rock in New Zealand.The project will provide fundamental information on the processes that underlie soil fertility, and how they shaped the distribution of intensive agricultural systems in the past (and could contribute to low-input systems today and in the future). Carrying out this research will require integrating information from ecology, soil science, hydrology, geochemistry, and anthropology; hence it will contribute to the conceptual and practical unification of disparate disciplines. It will support two post-doctoral fellows and several undergraduate students ? and those students and postdoctoral fellows will learn how to integrate a broad array of research fields. Finally, this project is closely aligned with ongoing efforts by Native Hawaiian organizations and institutions to understand and to restore the traditional pre-contact agricultural systems of Hawaii ? for educational and cultural purposes, and also to learn what those systems can contribute to present and future agricultural sustainability. This project will bring a scientific component to those efforts, and thus provide opportunities to teach and learn science that are integrated with the cultural and restoration efforts.