Issues in Water Quality Trading: Introduction to Featured Collection1

Heberling, Matthew T., 2011. Issues in Water Quality Trading: Introduction to Featured Collection. Journal of the American Water Resources Association (JAWRA) 47(1):1‐4. DOI: 10.1111/j.1752‐1688.2011.00510.x     

Featured Collection Introduction: Connectivity of Streams and Wetlands to Downstream Waters

Connectivity is a fundamental but highly dynamic property of watersheds. Variability in the types and degrees of aquatic ecosystem connectivity presents challenges for researchers and managers seeking to accurately quantify its effects on critical hydrologic, biogeochemical, and biological processes. However, protecting natural gradients of connectivity is key to protecting the range of ecosystem services that aquatic ecosystems provide. In this featured collection, we review the available evidence on connections and functions by which streams and wetlands affect the integrity of downstream waters such as large rivers, lakes, reservoirs, and estuaries. The reviews in this collection focus on the types of waters whose protections under the U.S. Clean Water Act have been called into question by U.S. Supreme Court cases. We synthesize 40+ years of research on longitudinal, lateral, and vertical fluxes of energy, material, and biota between aquatic ecosystems included within the Act's frame of reference. Many questions about the roles of streams and wetlands in sustaining downstream water integrity can be answered from currently available literature, and emerging research is rapidly closing data gaps with exciting new insights into aquatic connectivity and function at local, watershed, and regional scales. Synthesis of foundational and emerging research is needed to support science‐based efforts to provide safe, reliable sources of fresh water for present and future generations.     

Dissipation of Contaminants of Emerging Concern in Biosolids Applied to Nonirrigated Farmland in Eastern Colorado

In 2007, a 1.5‐year field‐scale study was initiated by the U.S. Geological Survey to evaluate the dissipation of contaminants of emerging concern (CECs) following a first agronomic biosolids application to nonirrigated farmland. CECs with the greatest decrease in concentration in the surface biosolids at 180 days post‐application included indole, d‐limonene, p‐cresol, phenol, and skatol. CECs that were present in the largest concentration in 180‐day‐weathered biosolids included stanols, nonylphenols, bisphenol A, bis(2‐ethylhexyl) phthalate, hexahydrohexamethyl cyclopenta‐benzopyran (HHCB), and triclosan. CECs that were detected in pre‐application soil were 3‐beta coprostanol, skatol, acetophenone, beta‐sitosterol, beta‐stigmastanol, cholesterol, indole, p‐cresol, and phenol, most of which are biogenic sterols or fragrances that have natural plant sources in addition to anthropogenic sources, yet their concentrations increased (in some cases, substantially) following biosolids application. Preliminary data indicate the nonylphenols (including NPEO1, NPEO2), OPEO1, benzo[a]pyrene, diethyl phthalate, d‐limonene, HHCB, triclosan, and possibly 3‐beta coprostanol, skatol, beta‐sitosterol, cholesterol, indole, and p‐cresol, migrated downward through the soil by 468 days post‐application, but indicated little uptake by mature wheat plants. This study indicates that some CECs are sufficiently persistent and mobile to be vertically transported into the soil column following biosolids applications to the land surface, even in semiarid regions.