This study shows quantitative and temporal offsets between nitrogen input and riverine output, using time series of three nested catchments in central Germany. The riverine concentrations show lagged reactions to the input, but at the same time exhibit strong inter-annual changes in the relationship between riverine discharge and concentration. The study found a strong retention of nitrogen that is dominantly assigned to a hydrological N legacy, which will affect future stream concentrations.

Mediterranean cork woodlands are very particular agroforestry systems present in a confined area of the Mediterranean Basin. They are of great importance due to their high socioeconomic value; however, a decrease in water availability has put this system in danger. In this paper we build a model that explains this system's tree-species distribution in southern Portugal from environmental variables. This could help predict their future distribution under changing climatic conditions.

Streamflow in high-elevation and high-latitude areas may be vulnerable to snow loss, making it important to quantify how snowmelt and rainfall are divided between soil storage, drainage below plant roots, evapotranspiration and runoff. We examine this separation in different climates and soils using a physically based model. Results show runoff may be reduced with snowpack decline in all climates. The mechanisms responsible help explain recent observations of streamflow sensitivity to snow loss.

High-latitude permafrost environments are changing rapidly due impacts and feedbacks associated with climate warming. We used streamflow and DOC concentrations as well as export estimates and optical indices to better understand how different surface water bodies transport and process dissolved material over multiple seasons and years. Information on DOM quality provides insight into organic material sources and possible composition changes related to higher summer rainfall in summer/fall.

We carried out a series of laboratory-controlled experiments in order to simulate different scenarios of practical interest aiming to analyze, from a dielectric point of view, the influence of different washing solutions on non-aqueous phase liquid (NAPL) removal. Furthermore, on the basis of the results obtained, we validated a dielectric mixing model for predicting the volumetric amounts of NAPL (θ_NAPL) within the contaminated soil as the decontamination process progressed.

The flow of water is often inferred from water levels and gradients whose measurements are considered trivial despite the many steps and complexity of the instruments involved. We systematically review the four measurement steps required and summarise the systematic errors. To determine the accuracy with which flow can be resolved, we quantify and propagate the random errors. Our results illustrate the limitations of current practice and provide concise recommendations to improve data quality.

Over the past decades, changes in land use and climate over Europe have impacted the average flow of water flowing through rivers and reservoirs (the so-called water yield). We quantify these changes using a simple but widely tested modelling approach constrained by observations of lysimeters across Europe. Results show that the contribution of land use to changes in water yield are of the same order as changes in climate, showing that impacts of land use changes cannot be neglected.

This study suggests an efficient approach to obtain plot-scale soil hydraulic properties for the shallow structural soils via non-invasive ground-penetrating radar measurements. Facilitated by spatial information of lateral water flow, this approach is more efficient than the widely used inversion approaches relying on intensive soil moisture monitoring. The acquisition of such quantitative information is of great interest to fields such as hydrology and precision agriculture.

This study aims to identify catchments and the associated water uses vulnerable to climate change. Vulnerability is considered here to be the likelihood of water restrictions which are unacceptable for agricultural uses. This study provides the first regional analysis of the stated water restrictions, highlighting heterogeneous decision-making processes; data from a national system of compensation to farmers for uninsurable damages were used to characterize past failure events.

In this study, we apply a data-driven approach to quantitatively estimate precipitation using weather radar data. The method is based on information theory concepts. It uses predictive relations expressed by empirical discrete probability distributions, which are directly derived from data rather than the standard deterministic functions.

There is a wide variety of modeling methods to designate precipitation as rain, snow, or a mix of the two. Here we show that method choice introduces marked uncertainty to simulated snowpack water storage (> 200 mm) and snow cover duration (> 1 month) in areas that receive significant winter and spring precipitation at air temperatures at and near freezing. This marked uncertainty has implications for water resources management as well as simulations of past and future hydroclimatic states.

Assessing how sensitive uncertain model parameters are to observed data can be done by analyzing an ensemble of model simulations in which the parameters are varied. In subsurface modeling, this involves running heavy models. To reduce time wasted simulating models which show poor behavior, we use a fast polynomial model based on a simple parameter decomposition to approximate the behavior prior to full-model simulation. This largely reduces the cost for the global sensitivity analysis.

In this study, we develop a topographic index explaining hydrological similarity within a energy-centered framework, with the observation that the majority of potential energy is dissipated when rainfall becomes runoff.

In this work a probabilistic rainfall nowcasting model, a non-hydrostatic high-resolution numerical weather prediction (NWP) model corrected with data assimilation, and a distributed hydrological model are used together with radar observations to implement a hydrological nowcasting chain. This chain is used to obtain a useful discharge prediction in small catchments with a time horizon of 2–8 h.

We tested a new method to simulate terrestrial evaporation in a hydrological model. Given physical constraints imposed by this model, it should help avoid the overestimation of terrestrial evaporation in climate change assessments. We show the good performance of the model by comparing simulated terrestrial evaporation to observations at three sites with different climates and vegetation. Overall, this research proposes a method that will improve our ability to make streamflow projections.

The impact of city trees for intercepting rainfall is quantified using measurements and modeling tools. The measurements show that an important amount of rainfall is intercepted, limiting the amount of water reaching the ground. Models are used to extrapolate the measurement results. The performance of two specialized interception models and one water balance model is evaluated. Our results show that the performance of the water balance model is similar to the specialized interception models.

Here, we study the main moisture sources of the two famous western Mediterranean flood events of autumn 1982 (October and November). Results confirm the hypothesis that a large amount of precipitable water was involved, which was to a great extent advected from the tropics and subtropics. This remote moisture transport occurred at medium levels of the atmosphere via moisture plumes or atmospheric rivers. During the October event the contribution of local sources was also important.

This article evaluates the influence of sediment representation in a sediment transport model. A short-term simulation is used to assess how far changing the sediment characteristics in the modelling experiment changes riverbed evolution and sediment redistribution during a small flood event. The study shows in particular that representing sediment with extended grain-size and grain-density distributions allows for improving model accuracy and performances.

The Amazon rainforest has undergone extensive land use change, which greatly reduces the rate of evapotranspiration. Forest with deep roots is replaced by agriculture with shallow roots. The difference in rooting depth can greatly reduce access to water, especially during the dry season. However, large areas of the Amazon have a sufficiently shallow water table that may provide access for agriculture. We used remote sensing observations to compare the impact of deep and shallow water tables.

A simple and effective index for the quantitative estimation of the evolution of human pressure on rivers at global scale is proposed. This index, based on nightlights and river discharge data, shows a significant increase from 1992 to 2013 worldwide. The most notable changes are found in river basins across Africa and Asia, where human pressure on rivers is growing markedly. This index identifies priority areas that can be targeted for the implementation of mitigation strategies and plans.

Watershed classification can identify regions expected to respond similarly to disturbance. Methods should extend beyond hydrology to include other environmental questions, such as ecology and water quality. We developed a classification for the Canadian Prairie and identified seven classes defined by watershed characteristics, including elevation, climate, wetland density, and surficial geology. Results provide a basis for evaluating watershed response to land management and climate condition.

In a context of climate change, the quantification of the contributions of glacier melt, snowmelt, and rain to the river streamflow is a key issue for assessing the current and future water resource availability. This study discusses the representation of the snow and glacier processes in hydrological models and its impact on the estimated flow components, and also addresses the issue of defining the glacier contribution to the river streamflow.

Lack of adequate instrumentation for monitoring nutrient availability in agricultural soils leads in most cases to over-application of fertilizers, often resulting in groundwater pollution. This research presents a novel approach for real-time, in situ monitoring of nitrate in soils using absorption spectroscopy techniques while preventing interference from dissolved organic carbon. Column experiments with this system resulted in accurate nitrate measurements in three different soil types.