Land surface albedo is a key parameter controlling the local energy budget, and altering the albedo of built surfaces has been proposed as a tool to mitigate high near‐surface temperatures in the urban heat island. However, most research on albedo in urban landscapes has used coarse‐resolution data, and few studies have attempted to relate albedo to other urban land cover characteristics. This study provides an empirical description of urban summertime albedo using 30 m remote sensing measurements in the metropolitan area around Boston, Massachusetts, relating albedo to metrics of impervious cover fraction, tree canopy coverage, population density, and land surface temperature (LST). At 30 m spatial resolution, median albedo over the study area (excluding open water) was 0.152 (0.112–0.187). Trends of lower albedo with increasing urbanization metrics and temperature emerged only after aggregating data to 500 m or the boundaries of individual towns, at which scale a −0.01 change in albedo was associated with a 29 (25–35)% decrease in canopy cover, a 27 (24–30)% increase in impervious cover, and an increase in population from 11 to 386 km−2. The most intensively urbanized towns in the region showed albedo up to 0.035 lower than the least urbanized towns, and mean mid‐morning LST 12.6°C higher. Trends in albedo derived from 500 m Moderate Resolution Imaging Spectroradiometer (MODIS) measurements were comparable, but indicated a strong contribution of open water at this coarser resolution. These results reveal linkages between albedo and urban land cover character, and offer empirical context for climate resilient planning and future landscape functional changes with urbanization.

Reducing soil disturbance may limit erosion, but many still consider tillage essential for seedbed preparation, particularly on poorly drained soils. ) and fi ve fertilizer (no fertilization, N-only, N+NPK starter, NPK+NPK starter, and NPK broadcast) treatments were evaluated. With N, P, and K fertilizer, yields were similar for tilled and NT treatments, averaging 8.73 Mg ha -1 for CC and 11.93 Mg ha -1 and 3.70 Mg ha -1 for rotated corn and soybean. Below recommended soil-test values resulted in NT yielding less than tilled treatments even though soil test P, K, and pH were similar. No-till with N, P, and K increased soil organic matter (OM) to 27.6 g kg -1 (20.5 g kg -1 in all other treatments), with the greatest increase from 0-to 5-cm. No-till treatments showed stratifi cation of P and K, but it had no eff ect on yield. No excessive pH stratifi cation was observed. Overall, fertilizer management predominantly infl uenced crop yield and with complete NPK management non-tilled yields were similar to tilled, even on fl at, somewhat-poorly drained soils. No-till with NPK management therefore may allow farmers to maintain high yields while reducing soil and nutrient losses. R.L. Cook,

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The interrelation between urban areas and land use options for greenhouse gas mitigation was evaluated by assessing the utility of urban residuals for soil reclamation. Long-term impacts on soil C storage for mine lands restored with urban organic residuals were quantified by sampling historic sites reclaimed both conventionally and with residuals-based amendments. Use of amendments resulted in greater C storage compared to conventional practices for all sites sampled, with increases ranging from 14.2 Mg C ha(-1) in a coalmine in WA to 38.4 Mg C ha(-1) for a copper mine in British Columbia. Expressed as Mg C per Mg amendment, effective C increases ranged from 0.03 to 0.31 Mg C per Mg amendment. Results were applied to three alternative land-use scenarios to model the net GHG balance for a site restored to forest or low-density development. The model included construction of 3.9 243 m(2)-homes, typical of urban sprawl. Emissions for home and road construction and use over a 30-year period resulted in net emissions of 1269 Mg CO2. In contrast, conventional reclamation to forestland or reclamation with 100 Mg of residuals resulted in net GHG reductions of -293 and -475 Mg CO2. Construction of an equivalent number of smaller homes in an urban core coupled with restoration of 1 ha with amendments was close to carbon neutral. These results indicate that targeted use of urban residuals for forest reclamation, coupled with high-density development, can increase GHG mitigation across both sectors.