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SUMMARY1. Water hyacinth (Eichhornia crassipes) is one of the world's most invasive aquatic plants and is known to cause significant ecological and socio-economic effects. 2. Water hyacinth can alter water clarity and decrease phytoplankton production, dissolved oxygen, nitrogen, phosphorous, heavy metals and concentrations of other contaminants. 3. The effects of water hyacinth on ecological communities appear to be largely nonlinear. Abundance and diversity of aquatic invertebrates generally increase in response to increased habitat heterogeneity and structural complexity provided by water hyacinth but decrease due to decreased phytoplankton (food) availability. 4. Effects of water hyacinth on fish are largely dependent on original community composition and food-web structure. A more diverse and abundant epiphytic invertebrate community may increase fish abundance and diversity, but a decrease in phytoplankton may decrease dissolved oxygen concentrations and planktivorous fish abundance, subsequently affecting higher trophic levels. 5. Little is known about the effects of water hyacinth on waterbird communities; however, increases in macroinvertebrate and fish abundance and diversity suggest a potentially positive interaction with waterbirds when water hyacinth is at moderate density. 6. The socio-economic effects of water hyacinth are dependent on the extent of the invasion, the uses of the impacted waterbody, control methods and the response to control efforts. Ecosystem-level research programmes that simultaneously monitor the effects of water hyacinth on multiple trophic-levels are needed to further our understanding of invasive species.

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ABSTRACT. There is broad support for the notion that ecosystem services influence human well-being (HWB), however, the means to measure such an effect are elusive. Measures of HWB are commonly used within the fields of psychology, economics, and international development, but thus far have not been integrated fully into ecosystem service assessments. We examine the multidimensional nature of HWB and discuss the need for a robust framework that captures its complex relationship with ecosystem services. We review several well-known HWB indices and describe the adaptation of two frameworks-the Economist Intelligence Unit's Quality of Life Index and the Sustainable Livelihoods Framework-to evaluate county-level HWB within the Albemarle-Pamlico Basin (Virginia and North Carolina, USA) using a stakeholder-engaged approach. We present maps of HWB that illustrate the results of both frameworks, discuss the feedback from stakeholders that guided indicator and data selection, and examine the observed differences in HWB throughout the basin. We conclude with suggestions for enhancing the role of ecosystem services in HWB indices.

SUMMARYProtected areas remain the most commonly used tool forin situconservation; however growth in the USA's system of public lands has stagnated while private land conservation continues to expand. Easements can provide a range of ecosystem services (ESs), but it is unknown whether conservation easements maintain ES capacities equivalent to public protected areas. Evaluation of the capacity of seven ESs on federal and state protected areas and conservation easements in the USA using spatially-explicit ES models and publicly available data indicated that ES capacities in easements were equal to or greater than capacities within state or federal protected areas for six of seven services and, when bundled together, conservation easements protected greater focal ES capacity than other conservation areas. Economic incentive programmes and regulatory mechanisms may be used to stimulate capacity improvements for surface water regulation, riparian filtration, erosion control, and carbon storage on conservation easements, and landscape-level conservation efforts should (1) continue to protect natural and uninhabited areas that provide ecosystem and biological diversity, (2) expand private conservation efforts close to human population centres, and (3) limit future development to areas with high regulating service capacity that can sustain new population growth.

Evans, Daniel M., C. Andrew Dolloff, W. Michael Aust, and Amy M. Villamagna, 2012. Effects of Eastern Hemlock Decline on Large Wood Loads in Streams of the Appalachian Mountains. Journal of the American Water Resources Association (JAWRA) 48(2): 266‐276. DOI: 10.1111/j.1752‐1688.2011.00610.x Abstract:  Eastern hemlock (Tsuga canadensis), a foundation species important to riparian forests of the Appalachian Mountains, is in decline due to the hemlock woolly adelgid (HWA) (Adelges tsugae). The effect of this insect on large wood (LW) production and recruitment to streams is largely unknown. We measured LW load, riparian forest composition, and T. canadensis health in 47 streams from Maine to Alabama and developed a conceptual model that frames the expected forest stand and instream LW response to the disturbance caused by HWA. In stands with HWA, 24.3% of the overstory T. canadensis basal area was stressed and 7.5% was dead, whereas only 3.0% was stressed and 2.0% was dead in stands without HWA. Mean T. canadensis effective LW load was 0.20 m3/100 m2 in streams with adjacent stands infested by HWA, almost three times higher than in streams flowing through uninfested stands (p = 0.048). Higher frequencies of LW were found at streams with HWA present and there was a positive association between the percent of dead T. canadensis and T. canadensis LW load (ρ = 0.4468; p = <0.0001). Greater total LW loads were associated with higher stream gradients, lesser bankfull widths, and streams at lower latitudes. Our research supports the hypothesis that HWA infestation of T. canadensis in riparian forest stands has increased LW loads in streams. This episodic disturbance to the riparian forest overstory may have lasting impacts on aquatic ecosystem structure and function.