Effects of herbaceous planting richness on water physicochemistry in created mesocosm wetlands

Abstract

In this study, we investigated the effect of herbaceous planting richness on the physicochemical parameters of water temperature, pH, and dissolved oxygen in created wetlands. Mesocosms were planted with common wetland plants along a gradient from zero species to four species and observed over three growing seasons. Aboveground biomass was harvested after the second growing season to simulate disturbance. Planting richness was not found to directly influence any of the parameters. Instead, it seems that algae were more influential on observed changes to pH or dissolved oxygen than the macrophyte. Traditionally, monitoring of mitigation wetlands focuses on growth of macrophytes (e.g. cover percentage) and eschews the importance of the algal community in water quality function. Our results suggest that inclusion of simple, low-cost measures of water physicochemical parameters in mitigation site performance monitoring may contribute to a better assessment of ecosystem function development in newly created mitigation wetlands. Further study is necessary to quantitatively assess the relationship, if any, between the physicochemical parameters of water quality and nutrient retention performance that is rarely evaluated in mitigation wetlands.

Planting richness affects the recovery of vegetation and soil processes in constructed wetlands following disturbance

“…This suggests that C inputs to unplanted mesocosms were more readily available to support respiration of the microbial community than the litter from the planted species (Uselman et al 2012). The high rates of CO 2 flux and the low rates of DEA in the unplanted mesocosms and some replicates of richness groups 1 and 2 were likely influenced by the abundance of algae produced in unplanted mesocosms (McAndrew et al, 2016) and mesocosms with little vegetative cover. Although it was not specifically measured, increased algal growth was observed in mesocosms with little to no vegetative cover throughout the year 3 growing season.…”

Designing Wetlands as an Essential Infrastructural Element for Urban Development in the era of Climate Change

“…Figure 1 summarizes the knowledge produced through our decade-long research on the three design elements and their relations to two major ecosystem services regarding water and habitat quality in created urban wetlands. The outcome of the research [4][5][6][7][8]16,17,[21][22][23][24][25][26][27][28][29][30][31][32][33] reveals how the design elements interact or are interrelated and how they influence key variables of wetland hydrology, soils, and plant community which drive and control the two ecosystem services ( Figure 1). Planners, designers, and wetland construction specialists may determine if their watershed development goals are best served through a specific combination of these design elements.…”

“…Finally, the third design element is PD [29][30][31][32][33]. Our team has been studying the biogeochemical processes and ecosystem functionality of urban wetlands since 2012 using a set of 60 ecological mesocosms (i.e., medium-sized, outdoor experimental tubs-see www.changwooahn.com for more) that allow controlled experiments and observation of PD and its relation to wetland ecosystem development.…”