In boreal and temperate regions, an estimated 15 × 10 6 ha of peatlands has been drained for forestry (Koskinen et al., 2011) and about 6 × 10 6 ha (about half the original Finnish peatland area) of these are in Finland (Paavilainen & Päivänen, 1995). Land use changes, such as drainage, have altered around 14–20% of global peatlands (Strack, 2008). Peat hydrology is important, as it regulates the structure and function of peat (Holden et al., 2006). Peatlands are essential stores for global carbon (Waddington et al., 2015 Yu et al., 2010). Peatlands cover large areas in the Boreal and Arctic landscape (Strack, 2008). Overall, with restoration, WT and storage properties recovered to the levels at undisturbed sites but increased runoff was observed occasionally due to wetter antecedent moisture conditions. Storage-related parameters (Sy, WT rise per rainfall input) and catchment response time parameters revealed disturbance-related hydrological changes in peatlands more clearly than other runoff parameters tested (e.g., RC). Shallow WT showed significant positive correlations with runoff and storage properties and was a key component of the runoff generation mechanisms in peatlands. Significantly higher watertable (WT) rise per rainfall input (0.36–0.85 cm/mm) was observed in Disturbed conditions, due to lower specific yield (Sy) values (0.13–0.24) than under Restored and undisturbed conditions (Sy 0.25–0.50). However, the base flow showed no noticeable difference between treatments. Mean event peak flow in Disturbed conditions was higher and peaked faster than under other conditions. Mean transit time revealed that event rainfall water reached the outlet faster in Disturbed conditions. RC in Disturbed conditions was slightly higher than in undisturbed conditions, but RC in Restored conditions was higher than under other conditions. Mean event runoff coefficient (RC) values varied greatly between conditions and hydrological events. In total, 455 and 728 hydrological events were selected for the analysis, using a three-event selection technique. This study compared five formerly Disturbed (now Restored) and two undisturbed peatlands. There is great uncertainty about how catchment hydrological processes change after restoration, with a particular lack of well-documented catchment runoff data. In practice, however, measuring the water fluxes to and from lakes accurately is not simple, because understanding of the various hydrological processes and the ability to measure the various hydrological components are limited.Potential benefits of peatland restoration by rewetting include carbon sequestration, restored biodiversity, and improved hydrological functions.
#Hydrological processes plus
Mathematically, the concept of a water budget is deceptively simple: income equals outgo, plus or minus change in storage. The fluxes of water to and from lakes with regard to each of these components represent the water budget of a lake. Lakes interact with all components of the hydrological system: atmospheric water, surface water, and groundwater.
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