Successional dynamics of a 35 year old freshwater mitigation wetland in southeastern New Hampshire

The long-term ecological success of compensatory freshwater wetland projects has come into question based on follow-up monitoring studies over the past few decades. Given that wetland restoration may require many years to decades to converge to desired outcomes, long-term monitoring of successional patterns may increase our ability to fully evaluate success of wetland mitigation projects or guide adaptive management when needed. In Portsmouth, New Hampshire a 4 ha wetland was constructed in an abandoned gravel quarry as off-site compensatory mitigation for impacts to a scrub-shrub swamp associated with property expansion. Building upon prior evaluations from 1992 and 2002, we conducted a floral survey in 2020 to compare results with prior surveys to document vegetation successional trends over time. In addition, we monitored the avian community throughout the growing season as a measure of habitat quality. The plant community mirrored documented successional trends of freshwater wetland restoration projects as native hydrophytes dominated species composition. Plant species composition stabilized as the rate of turnover, the measurement of succession, declined by nearly half after 17 years. Researchers should consider long-term monitoring of specific sites to better understand successional patterns of created wetlands as we documented long time frames required for the development of scrub-shrub swamps, red maple swamps, and sedge meadows. High species richness was attributed to beaver activity, topographic heterogeneity from Carex stricta tussocks, and the seed bank from the application of peat from the original wetland. Habitat heterogeneity of open water, herbaceous cover, and woody vegetation supports a diverse avian community including 11 wetland dependent species. Although the mitigation project has not created the full area of lost scrub-shrub swamp after 35 years, it has developed a structurally complex habitat and diverse avian community that effectively provides the functions and values of the impacted system.

Phosphorus Fluxes in a Restored Carolina Bay Wetland Following Eight Years of Restoration

Restoring wetlands on agricultural land can release soil P to surface waters. Phosphorus is a limiting nutrient in many freshwater systems, thus restricting its release will improve surface water quality. A P balance was used to examine how P was cycling in a Carolina Bay wetland eight years after restoration from prior-drained agricultural land. The change in soil P was evaluated between archived samples taken at restoration (2005), and eight years after restoration (2013). Measured P fluxes included atmospheric deposition, plant uptake, and loss to surface water outflow. The soil total P pool at the time of restoration was 810 kg P ha -1 . No significant (α=0.05) decrease in the soil P pool was observed. Atmospheric deposition contributed 7 kg P ha-1, plants accumulated 28 kg Pha-1 and incorporated 27 P ha-1 into woody biomass and 1 kg P ha-1 on the forest floor litter, and 1.7 kg P ha-1 was lost to surface waters draining the wetland. Because the loss of P to surface waters was small, and because runoff water concentrations of P declined through this period of study to concentrations below those likely to cause eutrophication (< 0.1 mg L-1), we concluded that the wetland was not contributing to the degradation of surface water quality of nearby streams following restoration. Further, relatively “isolated” wetlands such as that studied may be promising sites for future wetland mitigation projects due to limited impacts on surface water quality.

Educating Landowners on Forest-Based Alternative Income Streams in North Carolina: Program Evaluation and Lessons Learned

Forest-based payments for ecosystem services markets have grown considerably in recent years. Besides timber products from harvests, forests offer multiple nontimber and intrinsic benefits, which could be important sources of income for landowners. In summer 2019, we organized four region-specific educational workshops all across North Carolina to educate landowners, Extension agents, and natural resource professionals about these alternative forest-based income streams. In this article, we cover the topics included in those workshops, postworkshop evaluation, and lessons learned from those events, which provide useful insights for Extension and outreach professionals in program design and delivery in forest-based payments for ecosystem service markets. Study Implications This article presents the details of a program, postworkshop evaluation, and lessons learned, which serve as useful guidelines for Extension and outreach educators in designing and delivering similar programs in forest-based alternative income streams. Although markets for ecosystem services are improving worldwide along with increasing research and outreach efforts in forest-based intrinsic benefits, results from evaluation surveys suggest that attendees had limited knowledge in forest carbon markets, wetland mitigation banking, and conservation easements in North Carolina. More region-specific Extension and outreach programs highlighting the locally available nontimber market options are recommended all across the country. Similarly, partnerships with other state agencies and institutions in program planning, advertisement, and delivery would improve effectiveness of similar Extension and outreach programs.