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Alpine permafrost occurrence in maritime climates has received little attention, despite suggestions that permafrost may occur at lower elevations than in continental climates. To assess the spatial and altitudinal limits of permafrost in the maritime Southern Alps, we developed and tested a catchment-scale distributed permafrost estimate. We used logistic regression to identify the relationship between permafrost presence at 280 active and relict rock glacier sites and the independent variables (a) mean annual air temperature (MAAT) and (b) potential incoming solar radiation in snow free months. The statistical relationships were subsequently employed to calculate the spatially-distributed probability of permafrost occurrence, using a probability of ≥ 0.6 to delineate the potential permafrost extent. Our results suggest that topoclimatic conditions are favorable for permafrost occurrence in debris-mantled slopes above ∼2000 m above sea level (asl) in the central Southern Alps and above ∼2150 m asl in the more northern Kaikoura ranges. Considering the well-recognized latitudinal influence on global permafrost occurrences, these altitudinal limits are lower than the limits observed in other mountain regions. We argue that the Southern Alps' lower distribution limits may exemplify an oceanic influence on global permafrost distribution. Reduced ice-loss due to moderate maritime summer temperature extremes may facilitate the existence of permafrost at lower altitudes than in continental regions at similar latitude. Empirical permafrost distribution models derived in continental climates may consequently be of limited applicability in maritime settings.

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Ecosystem services provided by contemporary landscapes are different from those of the past, and this difference is influenced by the legacies of policies that incentivized wetland drainage without considering the impact on ecosystem services. Heterogeneity in ecosystem service legacies is rarely acknowledged or documented. Even less understood is the relative role of historical wetland type (e.g., swamps, fens) and contemporary land cover in shaping these heterogeneous outcomes. Here, we contrasted contemporary ecosystem services with a scenario of no wetland drainage in the Ruamahanga Basin, New Zealand, a region historically rich in wetlands. Using the high‐resolution Land Use Capability Indicator model, we mapped nitrogen retention, phosphorous retention, sediment retention, agricultural productivity, and flood mitigation at a 5‐m spatial resolution under these two scenarios. Our work supports the broad understanding that agricultural productivity has increased in contemporary landscapes, while flood mitigation and nutrient retention have decreased. Net losses in ecosystem services occurred for the majority of historical wetlands, while net gains were less common. However, spatially heterogeneous and divergent responses of ecosystem services to land cover changes reinforced the need for high‐resolution models to untangle the range of factors affecting ecosystem service provisioning. Contemporary land cover explained very little variation in ecosystem services. Initial conditions, however, played an important role in determining ecosystem service outcomes with losses of swamps being particularly problematic for net loss of ecosystem services provisioning. The maps we produced, and the algorithms underlying them, provide tools to envision both local‐ and broad‐scale effects of historical wetland drainage.

Global wetland loss has reduced biodiversity and ecosystem services. These declines have inspired many landholders to restore wetlands, but the success of these efforts remains unclear, in part, because quantifying ecosystem services requires diverse methods. Here, we blend participatory mapping and surveys, field measurements and high-resolution models to track ecosystem services from restored wetlands on private land. We ask: 1) What ecosystem services do people perceive from restored wetlands? 2) What modelled/field measured ecosystem services were enhanced through restoration? and 3) How do field measured, modelled and perceived ecosystem services in restored wetlands interact? Participating landholders mapped their restoration project and shared their perceptions of ecosystem services. Next, we modelled ecosystem service changes using the Land Use Capability Indicator (LUCI) model and contrasted these to field measured ecosystem services for each wetland. Landholders perceived ~6.5 services from their restored wetlands. For modelled services, restoration significantly enhanced nitrogen and phosphorous retention. For fieldmeasured services, restoration increased soil organic carbon by ~20%, soil permeability to water by ~27% and native plant species richness by ~15 species, while reducing plantavailable phosphorous by ~23%. Correlating across methods revealed that reduced plantavailable phosphorus and site age and size were associated with more perceived services, whereas an increase in plant species richness was not a good proxy for gains in measured, modelled or perceived services. Based on the diverse ecosystem services gained, demonstrated by multiple methods, we contend that private wetland restoration can be successful as well as leveraged to meet multiple management and policy objectives.

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