Doctoral Dissertation Research: Modern Pollen Spectra from Coasts and Lowlands of the Dominican Republic and Their Application to the Interpretation of Sedimentary Pollen Records

这项博士论文研究项目将通过对表层土壤和沉积物中的现代花粉的分析，来研究新热带低地和海岸植被是否由独特的花粉分类群组合所代表。虽然已经成功地从热带沉积记录中重建了过去的植被、气候和环境，但现代花粉记录的缺乏限制了对花粉-植被关系的了解，并限制了对热带沉积花粉的解释。在热带美洲大陆已经进行了几项现代花粉研究，但在加勒比海岛屿上进行的研究很少。此外，在研究热带干燥或季节性植被类型的现代花粉研究中，很少有人研究成熟的低地季节性干燥森林的光谱。这项博士论文研究项目将集中在多米尼加共和国低地和沿海地区的现代花粉谱，其中包括季节性干燥森林中的地点。这位博士生和同事将从各种植被类型收集现代花粉样本，包括草原、莎草湿地、红树林、海岸灌木丛、低地季节性干燥森林、潮湿低地半落叶森林和潮湿森林。这些样本将使用标准技术进行处理，通过光学显微镜对花粉和孢子进行计数。判别分析将用于将花粉数据分类为代表植被类型的组，并允许生成预测模型。然后，这个模型将被用于解释以前在多米尼加共和国西南部收集的沉积物岩心(和未来的沉积岩心)中的化石花粉组合。该项目将首次对大安的列斯群岛沿海和低地植被的现代花粉光谱进行研究。它将有助于了解加勒比植被类型，包括季节性干燥的热带森林的植物区系组成和多样性，这些森林正迅速从加勒比区域消失。该项目将加强对伊斯帕尼奥拉和整个加勒比地区低地和沿海湖泊的沉积花粉记录的解释，从而增进对加勒比植被和长期气候动态的了解。项目成果将有助于保护多米尼加共和国的自然资源。现代花粉数据和元数据将提交给拉丁美洲花粉数据库，这是一个免费下载的化石和现代花粉数据的集合，从而为其他研究人员今后的研究提供便利。作为博士论文研究改进奖，该项目将提供支持，使有前途的学生能够建立独立的研究生涯

This doctoral dissertation research project will examine whether neotropical lowland and coastal vegetation is represented by unique assemblages of pollen taxa through analysis of modern pollen from surface soils and sediments. While reconstructions of past vegetation, climate, and environment have been successfully derived from tropical sedimentary records, the lack of modern pollen records has limited knowledge about pollen-vegetation relationships and restricted the interpretation of tropical sedimentary pollen. Several modern pollen studies have been conducted in mainland tropical America, but few studies have been conducted on Caribbean islands. Furthermore, of the modern pollen studies examining tropical dry or seasonal vegetation types, few have examined spectra from mature lowland seasonally-dry forests. This doctoral dissertation research project will focus on the modern pollen spectra of lowland and coastal Dominican Republic, which includes sites in seasonally-dry forests. The doctoral student and colleagues will collect modern pollen samples from a variety of vegetation types, including grasslands, sedge wetlands, mangroves, coastal scrubs, lowland seasonally dry forests, moist lowland semi-deciduous forests, and humid forests. The samples will be processed using standard techniques with pollen and spores counted via light microscopy. Discriminant analysis will be used to classify pollen data into groups representing vegetation types and allow the generation of a predictive model. This model then will be applied to the interpretation of fossil pollen assemblages from previously collected sediment cores (and future ones) in the southwestern Dominican Republic. This project will be the first study of modern pollen spectra from coastal and lowland vegetation in the Greater Antilles. It will contribute to knowledge about Caribbean vegetation types, including the floristic composition and diversity of seasonally-dry tropical forests, which are rapidly disappearing from the Caribbean region. This project will strengthen the interpretation of sedimentary pollen records from lowland and coastal lakes on Hispaniola and throughout the Caribbean, thus providing improved understanding of Caribbean vegetation and climate dynamics across long time scales. Project results will assist in the preservation of natural resources of the Dominican Republic. Modern pollen data and metadata will be submitted to the Latin American Pollen Database, a collection of free-to-download fossil and modern pollen data, thereby facilitating future research by other researchers. As a Doctoral Dissertation Research Improvement award, this project will provide support to enable a promising student to establish an independent research career