Academic literature on the topic 'Serpent River Watershed (Ont.)'

Abstract The issues of downscaling the outputs of a global climate model (GCM) to a scale that is appropriate to hydrological impact studies are investigated using a temporal neural network approach. The time-lagged feed-forward neural network (TLFN) is proposed for downscaling daily total precipitation and daily maximum and minimum temperature series for the Serpent River watershed in northern Quebec (Canada). The downscaling models are developed and validated using large-scale predictor variables derived from the National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR) reanalysis dataset. Atmospheric predictors such as specific humidity, wind velocity, and geopotential height are identified as the most relevant inputs to the downscaling models. The performance of the TLFN downscaling model is also compared to a statistical downscaling model (SDSM). The downscaling results suggest that the TLFN is an efficient method for downscaling both daily precipitation and temperature series. The best downscaling models were then applied to the outputs of the Canadian Global Climate Model (CGCM1), forced with the Intergovernmental Panel on Climate Change (IPCC) IS92a scenario. Changes in average precipitation between the current and the future scenarios predicted by the TLFN are generally found to be smaller than those predicted by the SDSM model. Furthermore, application of the downscaled data for hydrologic impact analysis in the Serpent River resulted in an overall increasing trend in mean annual flow as well as earlier spring peak flow. The results also demonstrate the emphasis that should be given in identifying the appropriate downscaling tools for impact studies by showing how a future climate scenario downscaled with different downscaling methods could result in significantly different hydrologic impact simulation results for the same watershed.

Watershed runoff in areas with heavy seasonal snow cover is usually estimated using physically based conceptual hydrologic models. Such simulation models normally require a snowmelt algorithm consisting of a surface energy balance and some accounting of internal snowpack processes to be part of the modeling system. On the other hand, artificial neural networks are flexible mathematical structures that are capable of identifying such complex nonlinear relationships between input and output datasets from historical precipitation, temperature and streamflow records. This paper presents the findings of a study on using a form of time-delayed neural network, namely time-lagged feedforward neural network (TLFN), that implicitly accounts for snow accumulation and snowmelt processes through the use of logical values and tapped delay lines. The logical values (in the form of symbolic inputs) are used to implicitly include seasonal information in the TLFN model. The proposed method has been successfully applied for improved precipitation–runoff modeling of both the Chute-du-Diable reservoir inflows and the Serpent River flows in northeastern Canada where river flows and reservoir inflows are highly influenced by seasonal snowmelt effects. The study demonstrates that the TLFN with logical values is capable of modeling the precipitation–runoff process in a cold and snowy climate by relying on ‘logical input values’ and tapped delay lines to implicitly recognize the temporal input–output patterns in the historical data. The study results also show that, once the appropriate input patterns are identified, the time-lagged neural network based models performed quite well, especially for spring peak flows, and demonstrated comparable performance in simulating the precipitation–runoff processes to that of a physically based hydrological model, namely HBV.

Water in the western United States sustains multiple purposes despite being over-allocated, over-used, and o en quality-impaired. Interstate river watersheds, where rivers pass through jurisdictional boundaries of two or more states, face particular management challenges to facilitate cooperation across multiple state and local jurisdictional boundaries. This paper focuses on mechanisms of cooperation used to manage water quality across western interstate watersheds. A range of cooperative mechanisms were examined, from meetings to watershed management and creation of memoranda of understanding. To understand different stakeholders' perceptions of successful cooperation, fortyeight watershed professionals were surveyed across six study areas. Ordinal logistic regression analysis indicated that survey respondents perceived watershed organizations, watershed partnerships, and meetings as the most successful cooperative activities for addressing water quality issues. This paper discusses the relationships between mechanisms of cooperation and additional variables examined in the study, and offers insights into regional cooperation and social cohesion over shared environmental resources. Spanish En el oeste de los Estados Unidos, el agua tiene varios usos a pesar de su sobreasignación, sobreuso/explotación, y el frecuente deterioro de su calidad. Las “cuencas interestatales“ de esta región, referidas a aquellos ríos que cruzan dos o más estados, enfrentan desafíos particulares para la cooperación a través de múltiples fronteras estatales y jurisdicciones locales. Este artículo se enfoca en los mecanismos de cooperación para manejar la calidad del agua en estas cuencas. Se examinan reuniones de trabajo, consejos/manejo de cuencas, y la creación de memorandums de entendimiento. Para comprender las percepciones de cooperación exitosa, se entrevistaron a 48 profesionales de cuencas hidrográ ficas a través de seis áreas de estudio. Los entrevistados perciben los organismos/asociaciones de cuencas hidrográ ficas y sus respectivas reuniones, como las actividades de cooperación más exitosas para abordar las cuestiones de calidad del agua. El artículo analiza las relaciones entre los mecanismos de cooperación y otras variables, y ofrece una visión sobre la cooperación regional y la cohesión social sobre los recursos ambientales compartidos. French En dépit d'une eau souvent de mauvaise qualité et soumise à une surexploitation et une surutilisation, ce e ressource remplit de nombreuses missions dans l'Ouest des États Unis. Les bassins hydrographiques interétatiques (où les fleuves traversent les frontières juridictionnelles de deux États ou plus) rencontrent des problèmes de gestion particuliers, dont le dé fiest surtout de faciliter la coopération interétatique et les frontières juridictionnelles locales. Cet article met l'accent sur les mécanismes de coopération mis en place dans la gestion de la qualité de l'eau des bassins interétatiques de l'Ouest du pays. Un éventail de mécanismes de coopération a été examiné, allant de réunions à la gestion de bassins et la création de mémorandums d'entente. A fin de comprendre la perception d'une coopération réussie des différents acteurs, quarante-huit professionnels des bassins hydrographiques ont participé à une étude sur six cas. L'analyse de la régression logistique ordinale a révélé que les participants percevaient les organisations des bassins, les partenariats de bassins et les réunions comme les activités de coopération les plus réussies pour aborder les questions de qualité de l'eau. Cet article examine les liens entre les mécanismes de coopération et les variables additionnelles examinées dans ce e étude, et propose un aperçu de la coopération régionale et de la cohésion sociale concernant le partage de ressources environnementales.

Red-backed Salamanders (Plethodon cinereus) are widely used as a biological indicator of terrestrial ecosystem health in North America due to their large range, potentially high biomass and large influence on ecosystem regulation. Monitoring projects often overlook the potential influence of intraspecific interactions and how Red-backed Salamander (RBS) abundance and demographics can be affected by symbiotic relationships. The adult to juvenile ratio was explored in relation to presence of ants, tunneling, number of small and large burrows. It was found that between 2011-2015 there was a significant increase in small and large burrows. It was found that ants, small burrows and large burrows were significantly related to both maximum salamander counts and adult-juvenile ratios. The relationship between both abundance and demographics with ants showed a negative relationship, while small and large burrows had a positive relationship. Tunneling was found to have no statistical significance (Table 1, Table 2). These results highlight the importance of considering biotic interactions when analyzing indicator species populations. Future steps should include determining how both biotic and abiotic properties interact to influence RBS populations and determining what type of interspecific interactions are occurring under cover boards via controlled experiments.Les salamandres cendrées (Plethodon cinereus) sont largement utilisées comme des indicateurs biologiques de la santé des écosystèmes terrestres en Amérique du Nord, en raison de leur portée vaste, de leur biomasse potentiellement élevée et de leur influence importante au niveau de la régulation des écosystèmes. Les projets de surveillance négligent souvent l’influence potentielle des interactions intraspécifiques, ainsi que la façon dont les relations symbiotiques peuvent affecter l’abondance et la démographie de la salamandre cendrée (SC). L’abondance de la SC et le rapport entre le nombre d’adultes et de jeunes ont été explorés en relation avec la présence de fourmis, de leurs tunnels et du nombre de petits et grands terriers. On a déterminé qu’entre 2011 et 2015, il y a eu une augmentation importante du nombre de petits et grands terriers et que la présence de fourmis, de petits et grands terriers était fortement liée au nombre maximal de salamandres et aux rapports adultes-jeunes. Les rapports trouvés entre la présence de fourmis, l’abondance de la SC et la démographie de l’espèce ont présenté une corrélation négative, alors que la présence de petits et grands terriers a présenté une corrélation positive. L’excavation des tunnels n’avait pas d’importance statistique (Tableau 1, tableau 2). Ces résultats soulignent l’importance de considérer les interactions biotiques lors de l’analyse des populations d’espèces indicatrices. Les prochaines étapes devraient inclure l’identification de la façon dont les propriétés biotiques et abiotiques interagissent pour influencer les populations de la SC et de déterminer quels types d’interactions interspécifiques se produisent sous le couvert des expériences contrôlées.

Thesis (M.Sc.)--York University, 2005. Graduate Programme in Geography.
Typescript. Includes bibliographical references (leaves 128-133). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url%5Fver=Z39.88-2004&res%5Fdat=xri:pqdiss &rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR11877