Doctoral Dissertation Research: Vegetation Change and Land Degradation in the Lake Baringo Ecosystem, Kenya, East Africa: Evidence from the Paleorecord.

博士论文研究：东非肯尼亚巴林戈湖生态系统的植被变化和土地退化：来自古记录的证据。

• 批准号: 0503334
• 负责人: Kam-biu Liu
• 金额: $ 1.19万
• 依托单位: Louisiana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-03-15 至 2007-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0503334&HistoricalAwards=false
• 关键词: Doctoral; Dissertation; Research; Vegetation; Change

Palynology is a useful tool for the reconstruction of environmental changes due to both natural and anthropogenic causes during geological and historical times. This project will study the history of vegetational changes and land degradation in the Lake Baringo ecosystem, Kenya, East Africa, during the Holocene through the examination of fossil pollen, phytoliths, and microscopic charcoal in lake-sediment cores. The Lake Baringo ecosystem, a critical habitat for more than 500 avifaunal species and a source of livelihood for humans, is threatened by land degradation as a result of mounting population pressure in East Africa. Although some studies have used pollen to reconstruct the paleovegetation and paleoclimate of East Africa, very few palynological studies have focused on land degradation or desertification, considered one of the most serious environmental problems in Africa. The researchers will travel to Kenya and collect a series of long and short cores and surface sediment samples from Lake Baringo. These cores and surface samples will yield an extended chronology and also provide information on the spatial variations of pollen deposition and sedimentation rates within this large lake. A key objective of the research is to determine how recent changes in land-use and increased land degradation are reflected in the lake-sediment records. The researchers will analyze the sediment stratigraphy, microscopic charcoal, and pollen and phytolith assemblages to document the history of land degradation, climatic and vegetational changes, and variations in fire regimes in the Lake Baringo ecosystem. Satellite imageries of the lake catchment area have been obtained and, to enhance accuracy in classification, GPS points will be obtained during fieldwork for ground truthing. The study will produce a high-resolution Holocene pollen record from the semi-arid region of Kenya and one of only a handful from East Africa in general. It will contribute to knowledge on the role of natural versus anthropogenic causes for environmental changes in a critical environmental zone in East Africa during the late Holocene. Its findings will have significant policy implications on the conservation of biodiversity, lake restoration, land-use planning, and environmental management in the semi-arid regions of East Africa.

孢粉学是重建地质和历史时期由于自然和人为原因引起的环境变化的有用工具。该项目将通过对湖泊沉积岩芯中的化石花粉、植物硅体和微观木炭的检查，研究东非肯尼亚巴林戈湖生态系统在全新世期间的植被变化和土地退化的历史。巴林戈湖生态系统是500多种鸟类的重要栖息地，也是人类的生计来源，由于东非不断增加的人口压力，该生态系统受到土地退化的威胁。尽管一些研究利用花粉重建了东非的古植被和古气候，但很少有孢粉学研究侧重于土地退化或荒漠化，这被认为是非洲最严重的环境问题之一。研究人员将前往肯尼亚，从巴林戈湖采集一系列长短岩芯和表层沉积物样本。这些岩芯和表层样品将产生一个延长的年代学，并提供关于这个大湖内花粉沉积和沉积速率的空间变化的信息。这项研究的一个关键目标是确定最近土地利用的变化和土地退化加剧如何反映在湖泊沉积物记录中。研究人员将分析沉积地层、微观木炭以及花粉和植硅体组合，以记录巴林戈湖生态系统中土地退化的历史、气候和植被变化以及火灾制度的变化。已经获得了湖泊集水区的卫星图像，为了提高分类的准确性，将在地面实况工作中获得GPS点。这项研究将从肯尼亚半干旱地区产生高分辨率的全新世花粉记录，这是东非为数不多的记录之一。它将有助于了解在全新世晚期东非一个关键环境地带环境变化的自然原因和人为原因的作用。它的发现将对东非半干旱地区的生物多样性保护、湖泊恢复、土地利用规划和环境管理产生重大的政策影响。