A stalagmite from Prince of Wales Island grew episodically between ~75,000 and ~11,100 yr BP; interrupted by seven hiatuses. Hiatuses most likely correspond to permafrost development and a temperature drop of up to 5 °C from modern conditions. Intervals of calcite deposition place tight constraints on the timing of mild climatic episodes in Alaska during the last glacial period, when permafrost was absent, allowing water infiltration into the karst system. These periods of calcite deposition are synchronous, within dating uncertainties, with Greenland Interstadials 1, 10, 11, 12c, 14b-14e, 16.1a, 17.2, and 20c.

High permeability and rapid recharge in karst aquifers make them susceptible to contamination. We combined a groundwater vulnerability map with an environmental disturbance index to give an adaptable spatial tool for developing management strategies for a karst environment in the Reserva de la Biosfera Selva el Ocote (el Ocote), Chiapas, Mexico. Seventy-two per cent of the study area is classified as an area of least concern for management, with 60% falling within el Ocote. Consequently, although there are concerns regarding the vulnerability of the karst ecosystem, the lack of development and the natural protection of the ecosystem, the immediate need for remedial action by the area's managers is currently minimal. About 27% of the study area is classified by the composite model as of moderate concern, with 34% within el Ocote. This reflects a balance between areas of moderate and high vulnerability, but little disturbance. Based on the management zones created by this study, much of the sub-catchment is zoned as of least or moderate concern, where disturbance has not occurred. As such, the opportunity exists to prevent major human impacts on vulnerable areas and the entire ecosystem, but only if local stakeholders are incorporated into this process of limiting development.

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