Origin of the forest steppe and exceptional grassland diversity in Transylvania (central‐eastern Europe)

• DOI: 10.1111/jbi.12468
• Publication Date: 2015-02-03T06:01:42Z
• Authors: Angelica Feurdean; Elena Marinova; Anne B. Nielsen; Johan Liakka; Daniel Veres; Simon M. Hutchinson; Mihaly Braun; Alida Timar‐Gabor; Ciprian Astalos; Volker Mosburgger; Thomas Hickler
• Keywords: Steppe; Biome; Last Glacial Maximum

Abstract Aim The forest steppe of the Transylvanian Plain is a landscape exceptionally diverse steppe‐like and semi‐natural grasslands. Is this vegetation remnant once continuous temperate extensively cleared by humans, or has area, since last glacial, always been steppe? Understanding processes that drive grassland formation important because effective management biome critical to conservation European cultural landscape. Location Lake Stiucii, north‐western Romania, central‐eastern Europe. Methods We analysed multi‐proxy variables (pollen, coprophilous fungi, plant macroremains, macrocharcoal) from 55,000 year discontinuous sequence ( c . 55,000–35,000; 13,000–0 cal. yr bp ), integrating models pollen‐based cover, reconstruction, global atmospheric simulations archaeological records. Results Needleleaf woodland occurred during glacial Marine Isotope Stage MIS ) 3, but contracted at end period. Forest coverage 55% (early Holocene) 65% (mid‐Holocene) prevailed through Holocene, Bronze Age humans forests after 3700 was most widespread between 8600 , whereas grasses, xerothermic forbs were extensive 11,700 Cerealia pollen indicate presence arable agriculture 7000 Main conclusions have provided first unequivocal evidence for needleleaf 3 in region. Extensive prior challenging hypothesis lowlands never wooded following glaciation. However, these fully closed either, reflecting dry growing season conditions, recurrent fires anthropogenic impacts, which favoured persistence throughout Holocene. longevity natural grasslands region may explain their current exceptional biodiversity. This longer‐term perspective implies future climatic warming associated fire will maintain