Suchergebnisse

published_or_final_version ; Politics and Public Administration ; Doctoral ; Doctor of Philosophy

Introduced pests and diseases cause such devastation due, to a great degree, to a lack of natural enemies in their introduced range, and a lack of immunity within their new hosts as they have not previously been exposed to them (Tomoshevitch et al., 2013). The threat from new pests and pathogens is only set to rise as the rate of international trade increases, involving greater numbers of countries and trade routes, creating new pathways for their introduction. Similarly, the change in climate, e.g. increased temperatures and changed rainfall patterns, creates new habitats in which these damaging organisms can establish and thrive, making them a threat to more countries and plants. A key issue that scientists face is trying to predict which of these organisms could/will cause problems for plants in the future, and where. The overall aim of this project was to establish the basis for an International Plant Sentinel Network (IPSN) as an early-warning system for future pest and disease threats. The network would use enhanced monitoring of plants that are growing outside their natural regions for damage by all the organisms that exist in the new environment; i.e. 'sentinel plants'. Research has shown the potential power of using sentinel plants for identifying new pest organisms (Fagan et al., 2008, Baker et al., 2009, Britton et al., 2010, Kenis et al., 2011; Tomoshevitch et al., 2013, ISEFOR, 2015). As well as helping to identify 'unknowns' or 'future threats', research can also provide key information about pests and diseases that scientists already know but which are poorly characterised. The more scientists (and botanical institute) know, the better the management plans that can be put in place to prevent the introduction of such pests and/or slow or stop their establishment and spread. For this reason, the aim of the IPSN is to bring together experts from different backgrounds who work in plant health, including those working in governments, academic institutions and NGOs combined with staff working in botanic ...

Representing hydrologic connectivity of non-floodplain wetlands (NFWs) to downstream waters in process-based models is an emerging challenge relevant to many research, regulatory, and management activities. We review four case studies that utilize process-based models developed to simulate NFW hydrology. Models range from a simple, lumped parameter model to a highly complex, fully distributed model. Across case studies, we highlight appropriate application of each model, emphasizing spatial scale, computational demands, process representation, and model limitations. We end with a synthesis of recommended "best modeling practices" to guide model application. These recommendations include: (1) clearly articulate modeling objectives, and revisit and adjust those objectives regularly; (2) develop a conceptualization of NFW connectivity using qualitative observations, empirical data, and process-based modeling; (3) select a model to represent NFW connectivity by balancing both modeling objectives and available resources; (4) use innovative techniques and data sources to validate and calibrate NFW connectivity simulations; and (5) clearly articulate the limits of the resulting NFW connectivity representation. Our review and synthesis of these case studies highlights modeling approaches that incorporate NFW connectivity, demonstrates tradeoffs in model selection, and ultimately provides actionable guidance for future model application and development. ; National Socio-Environmental Synthesis Center from the National Science Foundation [DBI-1052875]; John Wesley Powell Center for Analysis and Synthesis - U.S. Geological Survey; U.S. Environmental Protection AgencyUnited States Environmental Protection Agency ; CNJ was supported by the National Socio-Environmental Synthesis Center under funding received from the National Science Foundation DBI-1052875. This work was conducted as a part of the North American Analysis and Synthesis on the Connectivity of Geographically Isolated Wetlands to Downstream Waters Working Group supported by the John Wesley Powell Center for Analysis and Synthesis, funded by the U.S. Geological Survey and U.S. Environmental Protection Agency. The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the U.S. Environmental Protection Agency. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. ; Public domain authored by a U.S. government employee

Governments worldwide do not adequately protect their limited freshwater systems and therefore place freshwater functions and attendant ecosystem services at risk. The best available scientific evidence compels enhanced protections for freshwater systems, especially for impermanent streams and wetlands outside of floodplains that are particularly vulnerable to alteration or destruction. New approaches to freshwater sustainability — implemented through scientifically informed adaptive management — are required to protect freshwater systems through periods of changing societal needs. One such approach introduced in the US in 2015 is the Clean Water Rule, which clarified the jurisdictional scope for federally protected waters. However, within hours of its implementation litigants convinced the US Court of Appeals for the Sixth Circuit to stay the rule, and the subsequently elected administration has now placed it under review for potential revision or rescission. Regardless of its outcome at the federal level, policy and management discussions initiated by the propagation of this rare rulemaking event have potential far-reaching implications at all levels of government across the US and worldwide. At this timely juncture, we provide a scientific rationale and three policy options for all levels of government to meaningfully enhance protection of these vulnerable waters. A fourth option, a 'do-nothing' approach, is wholly inconsistent with the well-established scientific evidence of the importance of these vulnerable waters.