Date of Award

Spring 5-10-2019

Level of Access Assigned by Author

Open-Access Thesis

Degree Name

Master of Science (MS)

Department

Ecology and Environmental Sciences

Advisor

Jacquelyn Gill

Second Committee Member

Jasmine Saros

Third Committee Member

Kirk Maasch

Abstract

Jamaica is located in the Caribbean biodiversity hotspot and has a rich flora and fauna, most notably characterized by exceptional levels of plant endemism. These natural resources are imperiled by climate change and increasing anthropogenic pressures, therefore highlighting the importance of implementing effective conservation programs to mitigate ecosystem degradation. Paleoecological studies that investigate the diversity and distributions of organisms and their habitats over millennial timescales provide critical long-term spatial and temporal context for the assessment of contemporary environmental problems. Lake sediments are a highly useful archive for the study of prehistoric climate and ecological changes, as biological, chemical and geophysical remnants of ancient environments sequentially accumulate on lake bottoms over time, thus providing an integrated record of past environmental variability. Jamaica’s prehistory is not well known from both an ecological and human perspective, therefore providing a special opportunity to apply paleoecological methods to the investigation of the past environments of an understudied area. This thesis investigates the paleoecological history of Jamaica within the context of millennial-scale relationships among humans, climate and the environment throughout the Holocene. Chapter 1 provides a review of the utility of lake sediment coring and paleoecological data for reconstructing past environments and climates, paleoenvironmental research in low-latitude environments and relationships among climate, biodiversity, and human populations in the tropics, and the history of climate, vegetation, fire and human activities in the Caribbean Basin as illuminated by prior paleoecological research. In sum, Chapter 1 provides a broader spatial context for understanding the timing and magnitude of paleoecological changes in Jamaica and allows for the framing of past changes in climate and human activities in Jamaica within a regional model of prehistoric environmental variability. Chapter 2 examines the paleoenvironments, paleoclimates and prehistoric human populations of Jamaica. A novel multiproxy paleoecological reconstruction that records prehistoric changes in climate, fire, vegetation and human activities in Jamaica from the mid-Holocene to modern times is presented. Four successive waves of human colonization were documented in the lake sedimentary record, including the arrival of the Ostionoid peoples, the first group to colonize the island. Initial colonization of the island was coeval with a period of increased fire regimes and large vegetation shifts, including the loss of a swamp mangrove-fern community which failed to re-establish after disturbance. Subsequent waves of colonization by the Meillacan peoples, Taino, and Europeans were associated with increases in fire activity above background levels. The paleoecological record revealed that the Maya Drought (AD 750-AD 950) was represented by arid conditions in Jamaica, while the Medieval Warm Period (AD 800-AD 1300) and Little Ice Age (AD 1400-AD 1800) were represented by wet and dry climates respectively.

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