Incorporating stakeholder engagement into environmental management may help in the pursuit of novel approaches for addressing complex water resource problems. However, evidence about how and under what circumstances stakeholder engagement enables desirable changes remains elusive. In this paper, we develop a conceptual framework for studying social and environmental changes possible through stakeholder engagement in water resource management, from inception to outcomes. We synthesize concepts from multiple literatures to provide a framework for tracing linkages from contextual conditions, through engagement process design features, to social learning, community capacity building, and behavioral change at individual, group, and group network levels, and ultimately to environmental change. We discuss opportunities to enhance the framework including through empirical applications to delineate scalar and temporal dimensions of social, behavioral, and environmental changes resulting from stakeholder engagement, and the potential for negative outcomes thus far glossed over in research on change through engagement.

Although many agricultural watersheds rely heavily on riparian buffer adoption to meet water quality goals, design and management constraints in current policies create adoption barriers. Based on focus group feedback, we developed a flexible buffer design paradigm that varies buffer width, vegetation, and harvesting. Sixteen years of daily-scale nutrient and sediment loads simulated with the Soil and Water Assessment Tool (SWAT) were coupled to the three-zone Riparian Ecosystem Management Model (REMM) to compare the effectiveness of traditional, policy-based buffer designs with designs that are more flexible and integrate features important to local farmers. Buffer designs included (i) 10 m grass, (ii) 15 m grass, (iii) 15 m deciduous trees, (iv) 30 m grass and trees, (v) 30 m grass and trees with trees harvested every 3 yr, and (vi) 30 m grass and trees with grass harvested every year. Allowing harvesting in one zone of the buffer vegetation (either trees or grasses) minimally affected water quality, with annual average percent reductions differing by <5% (p > .05; 76-78% for total nitrogen [TN], 51-55% for total phosphorus [TP], and 68% for sediment). Under the highest input loading conditions, buffers with lower removal efficiencies removed more total mass than did buffers with high removal efficiencies. Thus, by focusing on mass reduction in addition to percent reduction, watershed-wide buffer implementation may be better targeted to TN, TP, and sediment reduced. These findings have important implications for informing flexible buffer design policies and enhanced placement of buffers in watersheds impaired by nutrient and sediment. 1 INTRODUCTION Agricultural nonpoint source pollution is a global problem that causes tremendous environmental and economic

Biochars produced from cotton gin waste (CG) and guayule bagasse (GB) were characterized and explored as potential adsorbents for the removal of pharmaceuticals (sulfapyridine-SPY, docusate-DCT and erythromycin-ETM) from aqueous solution. An increase in biochar pyrolysis temperature from 350 οC to 700 οC led to an increase in pH, specific surface area, and surface hydrophobicity. The electronegative surface of all tested biochars indicated that non-Coulombic mechanisms were involved in adsorption of the anionic or uncharged pharmaceuticals under experimental conditions. The adsorption capacities of Sulfapyridine (SPY), Docusate (DCT) and Erythromycin (ETM) on biochar were influenced by the contact time and solution pH, as well as biochar specific surface area and functional groups. Adsorption of these pharmaceutical compounds was dominated by a complex interplay of three mechanisms: hydrophobic partitioning, hydrogen bonding and π–π electron donor–acceptor (EDA) interactions. Despite weaker π–π EDA interactions, reduced hydrophobicity of SPY− and increased electrostatic repulsion between anionic SPY− and the electronegative CG biochar surface at higher pH, the adsorption of SPY unexpectedly increased from 40% to 70% with an increase in pH from 7 to 10. Under alkaline conditions, adsorption was dominated by the formation of strong negative charge-assisted H-bonding between the sulfonamide moiety of SPY and surface carboxylic groups. There seemed to be no appreciable and consistent differences in the extent of DCT and ETM adsorption as the pH changed. Results suggest the CG and GB biochars could act as effective adsorbents for the removal of pharmaceuticals from reclaimed water prior to irrigation. High surface area biochars with physico-chemical properties (e.g., presence of functional groups, high cation and anion exchange capacities) conducive to strong interactions with polar-nonpolar functionality of pharmaceuticals could be used to achieve significant contaminant removal from water. Graphic Abstract

HighlightsWe developed a land suitability framework for sustainable manure utilization based on seven water quality-related environmental vulnerability factors.ArcGIS-based decision-support tools were developed that use readily available data for the U.S.The tools can be adapted to any location in the U.S. for any livestock agricultural system.In a case study, 19.9% of the study area was identified as potentially suitable for manure utilization.2%, 33%, and 44% of the potential areas were highly, moderately, and marginally suitable, respectively.Abstract. Intensive livestock agriculture is a significant source of nutrient pollution that contributes to water quality degradation worldwide. This study presents a land suitability framework and accompanying decision-support tools for sustainable manure management. The developed framework identifies potentially suitable areas for manure application in a user-defined area and further classifies the land as highly suitable, moderately suitable, marginally suitable, and unsuitable using seven environmental vulnerability factors considering landscape biophysical characteristics and proximity to streams. The decision-support tools, built in ArcGIS, were applied in a case study in western Pennsylvania. The ArcGIS toolbox, available from ScholarSphere (https://doi.org/10.26207/99tk-sn24), classified 2% of the case study area as highly suitable for manure application and 21% as unsuitable. Landscape slope and proximity to streams were the dominant vulnerability factors in the case study area. The framework and accompanying tools are transferable across watershed boundaries and can help identify areas where environmentally sustainable animal agriculture can be developed. Keywords: Decision-support tool, Land suitability analysis, Sustainable manure management, Vulnerability analysis.

Increased use of neonicotinoid-coated crop seeds introduces greater amounts of insecticides into the environment, where they are vulnerable to transport. To understand the transport of neonicotinoids from agricultural fields, we planted maize (Zea mays L.) seeds coated with thiamethoxam in lysimeter plots in central Pennsylvania. Over the next year, we sampled water generated by rainfall and snowmelt and analyzed these samples with mass spectrometry for the neonicotinoids thiamethoxam and clothianidin (metabolite), which originated from the coated seeds. For surface and subsurface transport, thiamethoxam exhibited "first-flush" dynamics, with concentrations highest during the first events following planting and generally decreasing for the remainder of the study. The metabolite clothianidin, however, persisted throughout the study. The mass of thiamethoxam and clothianidin exported during the study period accounted for 1.09% of the mass applied, with more than 90% of the mass transported in subsurface flow and less than 10% in surface runoff. These results suggest that surface runoff, at least for our site, is a relatively small contributor to the overall fate and transport of these insecticides and that the delivery ratio (i.e., mass exported/mass applied) observed for these compounds is similar to those of other trace-level emerging contaminants known to negatively influence aquatic ecosystems.