A 10,300 ¹⁴C yr Record of Climate and Vegetation Change from Haiti

Abstract

Pleistocene and Holocene vegetation dynamics in the American tropics are inferred largely from pollen in continental lake sediments. Maritime influences may have moderated climate and vegetation changes on Caribbean islands. Stable isotope (δ18O) study of a 7.6-m core from Lake Miragoane, Haiti, provided a high-resolution record of changing evaporation/precipitation (E/P) since ∼10,300 14C yr B.P. The Miragoane pollen record documents climate influences and human impacts on vegetation in Hispaniola. The δ18O and pollen data near the base of the core indicate cool, dry conditions before ∼10,000 14C yr B.P. Lake Miragoane filled with water in the early Holocene as E/P declined and the freshwater aquifer rose. Despite increasing early Holocene moisture, shrubby, xeric vegetation persisted. Forest expanded ∼7000 14C yr B.P. in response to greater effective moisture and warming. The middle Holocene (∼7000–3200 14C yr B.P.) was characterized by high lake levels and greatest relative abundance of pollen from moist forest taxa. Climatic drying that began ∼3200 14C yr B.P. may have driven some mesophilic animal species to extinction. The pollen record of the last millennium reflects pre-Columbian (Taino) and European deforestation. Long-term, Holocene vegetation trends in southern Haiti are comparable to trends from continental, lowland circum-Caribbean sites, suggesting a common response to regional climate change.

Asynchronous extinction of late Quaternary sloths on continents and islands

“…3). There is both archaeological and environmental evidence of considerable midHolocene human activity in the West Indies, including burning (14,52,53). From sediments in Lake Miragoa ne in Haiti, for example, charcoal influx increases dramatically and pollen of forest taxa (such as Palmae and Podocarpus) decline to near absence at Ϸ5,730 yr BP, accompanied by a major increase in pollen of Ambrosia, a disturbance indicator (52).…”

Por el camino verde: Long-term tropical socioecosystem dynamics and the Anthropocene as seen from Puerto Rico

“…After then, graminoid and woody charcoal incidence increases dramatically, together with significantly higher sediment input to the lagoon basin. The highest microcharcoal values occurred between 4.0 and 3.5 ka, a period that has been documented as very humid (Caffrey and Horn, 2014;Higuera-Gundy et al, 1999;Hodell et al, 1991;Rivera-Collazo et al, 2015). Burney et al (1994) argue that this charcoal incidence can be linked to human activity given that humidity levels would not have permitted naturally occurring spontaneous fires.…”

Morphology and genetics reveal an intriguing pattern of differentiation at a very small geographic scale in a bird species, the forest thrush Turdus lherminieri

“…Fine-scale differentiation in a bird species E Arnoux et al (Higuera-Gundy et al, 1999), which is the main habitat occupied by the forest thrush today. Whatever their origin, populations from Guadeloupe and Montserrat were not isolated long enough to develop reciprocal monophyly in mtDNA, although microsatellite data clearly show that these islands currently host differentiated gene pools.…”