As urbanization and forest fragmentation increase around the globe, it is critical to understand how rates of respiration and carbon losses from soil carbon pools are affected by these processes. This study characterizes soils in fragmented forests along an urban to rural gradient, evaluating the sensitivity of soil respiration to changes in soil temperature and moisture near the forest edge. While previous studies found elevated rates of soil respiration at temperate forest edges in rural areas compared to the forest interior, we find that soil respiration is suppressed at the forest edge in urban areas. At urban sites, respiration rates are 25% lower at the forest edge relative to the interior, likely due to high temperature and aridity conditions near urban edges. While rural soils continue to respire with increasing temperatures, urban soil respiration rates asymptote as temperatures climb and soils dry. Soil temperatureand moisture-sensitivity modeling shows that respiration rates in urban soils are less sensitive to rising temperatures than those in rural soils. Scaling these results to Massachusetts (MA), which encompasses 0.25 Mha of the urban forest, we find that failure to account for decreases in soil respiration rates near urban forest edges leads to an overestimate of growing-season soil carbon fluxes of >350,000 Mg C. This difference is almost 2.5 times that for rural soils in the analogous comparison (underestimate of <143,000 Mg C), even though rural forest area is more than four times greater than urban forest area in MA. While a changing climate may stimulate carbon losses from rural forest edge soils, urban forests may experience enhanced soil carbon sequestration near the forest edge. These findings highlight the need to capture the effects of forest fragmentation and land use context when making projections about soil behavior and carbon cycling in a warming and increasingly urbanized world. K E Y W O R D S carbon, CO 2 , forest edge, forest fragmentation, rural, soil respiration, soil temperature, urban | 3095 GARVEY Et Al.critical to investigate how soil carbon storage will change in the face of climbing global temperatures and pervasive land-use change, such as forest fragmentation and urbanization (Bradford et al., 2016;

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To investigate the effect that restoration has on the microbiome of wetland soils, we used 16S amplicon sequencing to characterize the soil prokaryotic communities of retired cranberry farms that were restored to approximate the peat wetlands they once were. For comparison, we also surveyed the soil communities of active cranberry farms, retired cranberry farms, and natural peat wetlands that were never farmed. Our results show that the prokaryotic communities of active cranberry farms are distinct from those of natural peat wetlands. Moreover, four years after restoration, the prokaryotic community structure of restored cranberry farms had shifted, resulting in a community more similar to natural peat wetlands than to active farms. Meanwhile, the prokaryotic communities of cranberry retired farms remained similar to those of active farms. The observed differences in community structure across site types corresponded with significant differences in inferred capacity for denitrification, methanotrophy, and methanogenesis, and community composition was also correlated with previously published patterns of denitrification and carbon sequestration measured from the same soil samples. Taken together, these results suggest that ecological restoration efforts have the potential to restore ecosystem functions of soils and that they do so by ‘rewilding’ the communities of resident soil microbes.