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Advances have been made in water resource investigation due to the implementation of mathematical models, the development of theoretical frameworks, and the evaluation of sustainability indices. Together, they improve and make integrated water resource management more efficient. In this paper, in the study area of the Duero River Basin, located in Michoacan, Mexico, we schematize a series of numerical indices of the Watershed Governance Prism to determine the quantitative status of water governance in a watershed. The results, presented as axes, perspectives, and prisms in the Axis Index, Water Governance Index, and Watershed Governance Prism Index, provide the conclusion that it is possible to establish and evaluate the Watershed Governance Prism Index using our numerical implementation of the Watershed Governance Prism theoretical framework. Thus, it is possible to define a quantitative status and evoke how water governance is being designed and implemented in a watershed. [ABSTRACT FROM AUTHOR]

Questions: The ecological condition of riparian habitats has been negatively altered by human activities and land‐use changes. The aims of this study were to evaluate: (a) how adjacent land use affects the ecological condition of riparian habitats; and (b) whether the ecological condition relates to riparian vegetation properties (i.e., structure, diversity, and species composition). Location: Watershed of the Duero River, in the state of Michoacán, Mexico. Methods: Sampling sites were established along the Duero River riverbank by considering three different land uses (i.e., native forest, agriculture, and urban). At each site, we assessed the ecological condition of riparian habitats with a riparian condition index (RCI) composed of six subindices, with 17 indicators. Using a survey of woody plants (DBH ≥ 2.5 cm) in 12 different 0.1‐ha sites, we assessed vegetation properties. Results: According to the RCI, 76% of the studied riparian habitats had a very poor ecological condition, and only one site scored an excellent condition. The values of all subindices as well as the RCI were significantly greater in the forest than in the agricultural or urban land uses. The significant relationships between the RCI and its components (subindices) with vegetation properties were all positive and explained between 22% and 73% of the variation in structural and diversity attributes, and between 48% and 66% in floristic composition. Conclusions: This study shows how human land‐use activities affect the ecological condition of riparian habitats and hence riparian forests. Overall, the RCI had a high predictive power for the vegetation properties of riparian forests. This information is critical for programs involved in the management, conservation, and ecological restoration of riparian habitats. Low‐cost and time‐efficient indices, such as the RCI, facilitate ecological condition assessments of riparian habitats not only by scientists but also by previously trained land managers and the general public. [ABSTRACT FROM AUTHOR]

Extreme floods are anticipated to become more frequent in a future warmer climate. However, the long-term alterations in flood patterns across different regions of Europe remain unclear. In this study, we present a 15,000-year record of extreme floods in the Duero River, located in the southwestern Atlantic region. We analysed slackwater flood sediments, quantified the discharge and timing of individual flood beds over millennial time scales, and identified their potential climate influences. The composite record includes at least 62 floods grouped into ten flood-rich periods (with an average duration of 230 years). A high-frequency phase of moderate-magnitude floods (>10 events) occurred at ∼11.6–11.5 ka, following a period of reduced flood activity during the Younger Dryas. Similar clusters of Early Holocene floods (10.8–10.3 ka, 9.5 ka) coincided with or preceded meltwater pulses from the North Atlantic. The absence of palaeoflood records with discharges exceeding 6100 m3/s during the Mid-Holocene suggests a decline in winter hydro-meteorological extremes. High flood magnitudes were recorded during transition periods toward cooler and wetter conditions at 4.4, 2.3, 0.5, and 0.11 ka with discharges ranging from 7600 to 10,000 m3/s. These periods were interpreted as indicative of a southward shift in cyclone tracks in Europe driven by negative phases of the North Atlantic Oscillation (NAO). Conversely, flood magnitudes decreased during past warmer climate conditions (1.7 ka, 0.9 ka, and the present), although flood frequency remained high. The current decline in flood frequency reflects an increase in flood regulation due to dams, but it is also consistent with the prevailing positive trend in the NAO observed over the last 40 years. • 15-ka record of extreme floods in one of the largest river catchments in S Europe. • Early Holocene flood-rich periods overlap frequencies of meltwater pulses. • Floods decrease during Mid-Holocene indicating a positive mode of NAO-like circulation. • Late Holocene flood clusters are associated with negative NAO and strong Siberian High. • Flood magnitude declined during past warm periods including the present time. [ABSTRACT FROM AUTHOR]

Herein we provide a framework for evaluating the spatiotemporal variation of nitrate and ammonium and their relationships with environmental and anthropogenic variables at different scales. Bimonthly samples were collected from 28 sites in the Duero River, Mexico, from May to December 2013. The river flow changed and lost connectivity during the dry season because more water was diverted for irrigation. Four sites had the highest nitrate and ammonium values (7.6 and 22.1 mg L -1 respectively), which were related to direct waste water discharge. The remaining 24 sites were analysed using a multivariate approach. Using hierarchical cluster analysis, seasonal trends were identified with two groupings during July and five in December. Sites were grouped into those with constant discharge and nitrates affected by springs and those with poor water quality (high concentrations of ammonium). Non-metric multidimensional scaling simultaneously revealed the variation in time and space, organised sites into an environmental ammonium gradient and differentiated between seasons according to nitrate levels. Regression tree analysis established a relationship between nutrients and independent variables. At the landscape level, the agricultural area affected nitrate (75%) and urban area affected ammonium (45%); at the basin level, road density influenced both parameters (10.68 km per 25 km2). [ABSTRACT FROM AUTHOR]

Summary: In the present work we analyse the temporal trend of water supplies to a network of basins, representative of the Mediterranean climate and plant cover, and its relationship with the evolution of temperatures, precipitation, and the changes that have occurred in the plant cover with time. The results point to an important decrease in water supply, with a high degree of dependence on precipitation (r =0.85; p-value<0.001). Important changes are also seen in the monthly distribution of water discharges due to modifications that have occurred in the intra-annual distribution of precipitation and an increase in temperatures in spring and summer. The rivers studied are losing their snow regime, with very important reductions in the winter and spring discharges. The results show that to date the changes detected in the forest have not affected the water discharges of the rivers. This absence of effect is probably because the changes observed in the plant cover are currently below the threshold after which it is possible to detect the effect of the forest on water discharges and because the interannual variability in rainfall and discharge in Mediterranean environments is so high that it masks other time-dependent changes. The planning and management of water resources should take these changes into consideration with respect to the functioning of hydroclimatic systems. [Copyright &y& Elsevier]