## 1 Introduction  
Thermokarst lakes and drained thermokarst lake basins (DTLBs) are important indicators of permafrost and thermokarst dynamics in arctic and subarctic lowlands with ice-rich permafrost [1, 2, 3, 4, 5]. In Alaska, they occupy a large portion of the Arctic Coastal Plain, the Arctic Foothills and the Seward Peninsula [6, 7, 8], forming a complex and dynamic landscape with repeated cycles of lake formation and drainage due to permafrost degradation and aggradation [9, 10, 11]. Moreover, DTLBs accumulate soil organic carbon (SOC) in the form of peat, which has important implications for northern SOC pool distribution and high-latitude carbon cycling [10, 12, 13]. Recent attention has focused on the effect of projected climate warming on the rate of microbial decomposition of SOC stored in northern permafrost and peatland regions that will have an impact on greenhouse gas release to the atmosphere [14, 15, 16, 17]. Under warming conditions, northern SOC pools have the potential for large emissions of methane (CH\({}_{4}\)) or carbon dioxide (CO\({}_{2}\)), depending on the soil aerobic regime, due to an enhanced rate of microbial decomposition of organic matter that will serve as a positive feedback to climate warming [17, 18]. However, the amount of carbon sequestered in DTLBs and its role for the carbon budget in permafrost regions in a warming scenario is yet to be quantified for the Arctic. [PERSON] _et al._[10] and [PERSON] _et al._[12] demonstrated that basin age can be used to estimate peat thickness and accumulation rates in DTLBs. Long-term dynamics of DTLBs are characterized by post-drainage changes in vegetation, surface hydrology, soils characteristics and often permafrost aggradation, following a relatively predictable pattern reflecting successional stage or the relative age of the drained basin [9, 10, 12, 19, 21]. Important processes that shape the evolution of thermokarst lakes and DTLBs include permafrost thaw, ground subsidence and related erosion, ponding, surface and subsurface lake drainage, as well as post-drainage ground ice accumulation and frost heave [5, 20, 21]. Various models of a \"thaw-like cycle\" were proposed to explain the geomorphic processes of origin and drainage of thermokarst lakes [21, 22, 23, 24]. The cycle may begin with formation of ponds at the intersection of ice-wedge troughs and in low-center polygons, which upon continued permafrost thaw, eventually coalesce and enlarge to small lakes. As a result of thermo-mechanical shore erosion and thawing, like dimensions increase over time, both radially and in depth depending on the excess ice content of the permafrost [25, 26, 27]. A first cycle is ended when lake drainage is triggered by stream piracy, tapping, bank overflow or ice-wedge erosion [22, 28]. In thin discontinuous permafrost, thermokarst lakes may drain internally through open talks [20]. Following drainage, re-vegetation and peat accumulation begins in drained basins [10, 19, 29, 30]. Wet, graminoid vegetation is established in recently drained basins in 5-10 years, and peat accumulation starts in the first 20-100 years since drainage [10]. As a result of exposing the lake bottom, cold winter frost can penetrate into the ground, and new permafrost aggradation begins in the drained lake basin [31]. Additionally, over time, basin productivity decreases as wet graminoid vegetation communities, including productive grass (_Calamagrostis_ and _Duponia_) and sedge fens (_Carex aquatilis_), are replaced by ericaceous bog and tussock-dominated ecosystems. [PERSON] _et al._[32] have shown very high Gross Primary Productivity (GPP) for graminoid vegetation of younger DTLBs compared to the vegetation community of older DTLBs in Arctic ecosystems. This vegetative succession occurs as nutrients from the fresh lake sediments are consumed, permafrost aggradation causes limitations in rooting depth and liquid water availability, and ground ice formation and frost heave result in surface drying [10, 32].