Stable C isotope data of southern mixed-grass prairie vegetation from Oklahoma, United States

Stable carbon isotopic data (δ(13)C) of 41 individual plant species was collected from long-term grazed and ungrazed pastures in Oklahoma, USA. These data can serve as a library of stable carbon isotope values for Southern mixed-grass prairie species. Seventeen warm-season (C(4)) and twenty-four cool-season (C(3)) plants were identified and collected from the United States Department of Agriculture (USDA) Southern Plains Experimental Range (SPER). Plant samples were dried at 55°C, and ground finely. The δ(13)C isotopic compositions were determined using a Europa Scientific automated nitrogen carbon analyzer (ANCA/NT) with a Solid/Liquid Preparation Module (Dumas combustion sample preparation system) coupled to a Europa 20–20 Stable isotope analyzer continuous flow isotope ratio mass spectrometer (Sercon Ltd, formerly Europa Scientific Ltd., Crewe, England). These data can be used as end members in isotopic mixing models or in paleoecology to correlate soil ages with plant species composition. Data from plant species provides information about soil organic carbon sequestration and possible long-term climate change.