![]() Initially focused on reducing water discolouration at source and lowering the amount of chemicals and energy required to treat the water to potable standards 8, more recently rewetting is being considered part of the natural flood management toolbox 9. Water companies have also invested in rewetting peatlands, where they drain into the rivers and reservoirs used for drinking water supplies. Typically, restoration is carried out by conservation organisations, non-governmental organisations, landowners and multi-group partnerships, who have developed the necessary knowledge and practical skills. Wetland rewetting is a voluntary activity for reporting under the Kyoto Protocol 7, consequently, governments and businesses are increasingly investing in peatland restoration through carbon trading initatives. However, roughly 10% of the worlds peatlands are degraded 2 due to drainage for forestry or agriculture, burning, overgrazing, extraction for horticulture and climate change 3, 4, 5, so instead of slowly drawing down and storing carbon, many of these peatlands are rapidly releasing carbon, exacerbating the current climate emergency 5, 6. Over thousands of years these organic rich peat soils can become several meters thick. They form where waterlogged conditions restrict soil decomposition, enabling a slow build-up of partially decomposed plant material. Peatlands are the world’s largest terrestrial carbon store, estimated to hold ~ 500 ± 100 gigatonnes of carbon 1, despite only covering 3% of the global land area. Whilst restoration is crucial in halting the expansion of degraded peatland areas, it is vital that practitioners and policymakers advocating for restoration are realistic about the expected outcomes and timescales over which these outcomes may manifest. Restoration has had a dramatic effect on hydrology, however, consequent changes in other ecosystem functions were not measured in the 4 years after restoration. Soil respiration did not decrease as water tables rose, but methane emissions were higher from rewet pools. Despite these changes, there were no effects on photosynthesis, ecosystem respiration or dissolved organic carbon loads leaving the site. In the surrounding haggs water tables stabilised, as drawdown during dry conditions reduced, increasing the saturated peat thickness. These retained surface water over half the time and were deeper during wet periods than before. ![]() Restoration significantly reduced discharge from the site, transforming peat pans into pools. ![]() As the range of peatland types being restored diversifies, do previous findings present overly optimistic restoration expectations? In an eroding and restored upland peatland we assessed short-term (0–4 year) effects of restoration on ecohydrological functions. Peatland restoration is experiencing a global upsurge as a tool to protect and provide various ecosystem services. ![]()
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