Striking differences in runoff properties are found in experimental plots located in characteristic land surfaces in the North East New Caledonia. Annual runoff coefficients are in the range of 0.28–0.82 for a forest degraded by invasive mammals (deer and wild pigs), 0.06–0.16 for a woody savannah, and 0.01–0.03 for a healthy forest. It is proposed that arrangement of these three land surfaces in the landscape may control runoff properties at the scale of a watershed.

Emergent groundwater springs (dots) and associated wetlands (gray shading) in the Fool Creek catchment at the Fraser Experimental Forest, Colorado. The chemical composition of springwater reflected distinct groundwater sources and varied with elevation and among catchment zones. Acid neutralizing capacity (see Figure) and other inorganic constituents were more concentrated in springwater emerging from several springs in a geologically faulted portion of the catchment, and these had a predominant effect on downstream ion concentrations.

Monitoring at the Marcell Experimental Forest (MEF) catchments in northern Minnesota, USA, is unique from typical mountainous research catchments. We provide an overview of available data and metadata that are archived and available through community repositories. The research programme fills an important role in environmental monitoring and research on hydrology, ecology, biogeochemistry, and environmental change.

Runoff under no-tillage at catchment/hillsope scale.

We use a combination of low-cost and low-technology with traditional methods to measure the major components of the water balance of the Peri Lake Experimental Catchment, a 20 km² subtropical coastal lake catchment in Southern Brazil. (a) Location of monitoring sites and instrumentation. (b, c) Rainfall interception equipment. (d, e) Overland flow detector and groundwater level equipment. (f, g) Streamflow measurements. (h, i) Rainfall interception patterns. (j, k) Overland flow observation and active drainage network. (l, m) Baseflow and velocity scaling relationships.

This paper summarizes findings from 37 years of monitoring of an Arctic tundra river, including results from the longest known experimental nutrient enrichment of any river. The study documented notable trends (e.g., increasing nitrate, decreasing organic phosphorus) that would have been difficult or impossible to identify from short-term studies. It also substantiated conclusions from earlier, short-term experiments. The project has informed numerous stream catchment studies in the Arctic and beyond.

The tissue and data pipelines for the BIFoR FACE catchment.

• Research in the Kiryu Experimental Catchment (KEW) began in 1967 to elucidate the hydrological and biogeochemical processes in the forested catchment in relation to climate, geology, soil, and vegetation growth.
• The ratio of annual direct runoff to precipitation, as well as the sediment transport, was larger in the last decade in response to the rainfall patterns.
• Our data presented here suggest that a close relationship exists between the climate condition, rainfall-runoff response, sediment dynamics, as well as a slowly progressing change of forest condition.

Ressi is a small forested catchment located in the Italian pre-Alps. The site became an experimental catchment to investigate the water fluxes in the soil–plant–atmosphere continuum and the impact of vegetation on runoff generation in 2012. The field set up includes measurements of the rainfall, streamflow, soil moisture at various depths, and depth to water table. Precipitation, stream water, shallow groundwater, soil water, and plant water are sampled for tracer analysis.

Water sources in a mountain river were evaluated using stable isotopes of water. Stable isotope ratios varied strongly with mean watershed elevation. Depleted isotope in spring reflect snowmelt moving quickly through the watershed, and enriched summer isotope ratios suggest that groundwater is sourced from low elevation areas and recharged by winter precipitation. Our results suggest that baseflow in the Snoqualmie River may be relatively resilient to predicted warming and subsequent changes to snowpack in the Pacific Northwest.

Stable isotope in 25 Thai rivers was carried during 2013–2015. The national spatiotemporal variability showed that δ¹⁸O decreased latitudinally. The d-excess values were high in the southern region and low in the northeast region due to evaporation effect.

Approach to quantify ET_act, GWR and water inflow that considers the specific conditions of irrigated agriculture in warm, acid environments. It combines soil moisture and energy balance monitoring, remote sensing data analysing data analysis and numerical modelling using Hydrus. The final model results suggest that GWR accounts for one third of the total water inflow, of which 77% originates from irrigations.

Filtered (0.45 μm) and unfiltered water had the same rate of DOC degradation. Adding high concentration of POM to stream water decreased the overall DOC loss over 70 hours.

The results suggest that there is a descending trend for TWSA and GWSA over Turkey with a total loss of 11 and 6 cm respectively. The statistical analysis results also indicate that the monthly variations of GWS over Turkey are highly correlated with precipitation and more strongly with temperature at 2-month lag. The analysis of the climatology (long-term) values of monthly GWSA, precipitation and temperature also revealed high agreement between the variables.

• Novel approaches are proposed for estimating catchment-scale transit time (TTD) and evapotranspiration time (ETTD) distributions with a case study application to a mountain headwater catchment.
• Composite TTDs best matched the observations for periods up to approximately 1 month, but a Gamma TTD was most appropriate thereafter and most accurately described ETTD at all timescales.
• The proposed approaches are computationally inexpensive, robust to moderate gaps in input data, and thus broadly applicable to mountain and/or seasonally dry catchments worldwide.

In this study, water-carbon fluxes were measured using eddy covariance systems in two irrigated farmlands (sunflower and maize) in arid area of China to examine water use efficiency (WUE) of maize and sunflower and its responses to both environmental and physiological factors. We found vapour pressure deficit (VPD) was the most important factor restricting WUE of sunflower and maize. Abundant soil moisture with irrigation and shallow groundwater contributes to the negative correlation between soil moisture and WUE. The impact of crop leaf area index (LAI) and canopy conductance (g_c) to WUE depend on VPD ranges.

• Adjusted Budyko framework accounting for glacier runoff was developed for runoff alteration attribution.
• Contribution of glacier runoff to total runoff alteration was quantified.
• Driving mechanism of runoff alterations showed significant spatio-temporal heterogeneities.

The response of surface water-groundwater exchange processes in glacial aquifers to sediment heterogeneity and hydrologic hot moments are critically evaluated using spectral and flow pattern analyses. Results indicate that significant flows during storms alter groundwater flow patterns, even between consecutive storm events, and that sediment heterogeneity strongly controls the magnitude of flow and solute transport.

Stream temperatures across a montaine stream-lake network are related to the hydrologic influence of upstream lakes during summer and fall seasons, creating a complex stream temperature profile.

This study presents a quantitative, conceptual framework to explore how flow regime and stream network hydraulic scaling factors co-determine the relative temporal variability in wetted channel drainage density, L. Although we find that variability in L is universally damped relative to variability in streamflow (Q), the relationship is elastic, meaning that for a given increase in the variability in Q, headwater catchments will experience greater-than-proportional increases in the variability of L, making headwater catchments particularly vulnerable to climate change.

This manuscript is the first globally to quantify changes to overland-flow (incidence, magnitude and water-quality) induced by a hedgerow wild-margin within a grassland landscape through direct field-based observations as well as subsequent modelling. This fills a substantial knowledge gap within the hydrological understanding of hedgerows, as well as improves the understanding of runoff generation processes within agricultural catchments.

The form resistance caused by stems is much greater than that of litter for the same cover level, which implies that stem cover contributes more than litter cover to increasing the flow resistance and reducing the flow ability for sediment detachment and transport.

• Effects of tree species and meteorological factors on stemflow generation depend on rainfall type.
• Under rainfall types with high amount and high intensity, stemflow intensity has a significant positive correlation with rainfall intensity at the 5-min interval scale.
• The lag time between the start of rainfall and stemflow under high-intensity, short-duration rainfall type is the shortest, while the duration of stemflow after rain cessation under high-amount, long-duration rainfall type is the largest (maximum 4.3 h).

The impacts of modifying a threshold-based to a relative saturation-based soil water modelling approach was tested for the Soil and Water Assessment Tool. Differences in approach led to a regime shift in percolation from a few, high magnitude events to frequent, low magnitude events. Changes directly impacted the water balance and a range of biophysical predictions.

The heat budget of a moderately sized river is analysed throughout the supercooling process during river freeze-up. Individual heat fluxes are quantified and their relative significance during six individual supercooling events is highlighted, with a focus on the significance of outgoing longwave radiation. Several different equations for calculating the latent and sensible surface fluxes are compared and specific equations are recommended for use on daily and sub-daily timescales.

• Toona Sinensis (3.89 ± 3.87 L·day⁻¹) had significantly higher daily sap flow than Coriaria nepalensis (0.33 ± 0.37 L·day⁻¹) and Populus adenopoda (0.09 ± 0.12 L·day⁻¹);
• Over the entire study period, plants mainly used water from the surface soil horizons;
• A greater proportion of epikarst water was used for Coriaria nepalensis than by Toona sinensis and P. adenopoda over the whole growth stage, and more epikarst water was used in early and mid-growth stages compared to the late stage for the three species

• The evaporation enrichment of surface water is higher in summer, lower in autumn, higher in deserts and lower in mountains.
• The higher the temperature, the greater the evaporation loss; the higher the air humidity, the greater the evaporation loss.
• The construction of reservoirs and farmland irrigation will also increase the evaporation loss.

Blocking of pipe outlets in a heavily degraded UK blanket bog led to new pipe outlets appearing or seepage occurring around blocks within 90 days of blocking. Two pipes at head locations contributed more to streamflow compared to two pipes at edge locations, altogether they accounted for 11.3 % of streamflow. The degree of water-table drawdown in gully edges is thought to relate to piping activity. Peatland practitioners should consider control measures that reduce pipeflow further upslope of pipe outlets.

A theoretical flow resistance equation for open channel flow was tested using flow measurements carried out in a channel equipped with three types of riparian plants (Salix alba L., Salix caprea L. and Alnus glutinosa L.). Experimental runs were carried out with no vegetation and for nine vegetated conditions. The flow resistance law, coupled with the relationship for estimating the Γ function of the velocity profile having a scaling factor different for each investigated vegetation type, allowed an accurate estimate of the Darcy-Weisbach friction factor. The analysis of the vegetation species with few leaves or leafless demonstrated that the scaling factor of the Γ function resulted strongly related to the bending stiffness.

• Geomorphology-based ecohydrological model (GBEHM) model is introduced to study snowmelt and runoff dynamics in an alpine river basin
• We quantitatively analysed snowmelt contributions to hydrological processes
• Seasonal variation in snowmelt's hydrological contributions were detected
• Annual snowfall, snowmelt, snow evaporation and sublimation differ by elevation
• GBEHM model has potential applicability in other high-elevation regions that get seasonal snow cover

Actual evapotranspiration increases more rapidly in Pinares than in the Caatinga. Taking Caatinga as a hydrological mirror, some consequences are expected to Pinares, such as significant changes in the water balance, increase of biodiversity vulnerability and reduction of water availability in soil and reservoirs.

We developed a new vegetation-change water-balance approach to examine the effects of biomass reductions on forest health and streamflow. During dry periods, most of the water made available from biomass reductions was partitioned to transpiration of the remaining trees. During wet periods, this partitioning shifted to streamflow.

Groundwater resource observatory for Southwestern Madagascar (GROSoM).