Tile discharge increases once precipitation amount exceeds the soil moisture deficit (i.e., SMD + Precipitation = 0). The increase in discharge is largely the result of the mobilization of stored pre-event water, as event water contributions remain consistent across antecedent wetness conditions. The shift from dry to wet antecedent conditions and the changing water sources results in a decrease in dissolved reactive phosphorus (DRP) concentration.

What controls the interannual variability of groundwater recharge in northern New England? Precipitation, temperature, atmospheric pressure and height, and various teleconnection indices were tested against recharge using random forest machine learning models. Precipitation outside of months which typically have the largest recharge were the most important variables in explaining recharge. The interannual variability of summer/fall minimum streamflows was related to summer precipitation at all wells in the study area and to recharge-year recharge and summer air temperatures at only a few wells.

(1) Salix matsudana Koidz uses 20–100 cm soil water and groundwater. (2) Salsola affinis uses 0–60 cm soil water. (3) The surface evaporation depth reached 60 cm in riparian wetlands. This paper uses stable isotope technology (δD and δ¹⁸O) and Iso-Source model to study the seasonal variation and difference in water use patterns of S. affinis and S. matsudana Koidz in a typical riparian wetland in the arid area. The research results help to understand the ecological hydrological cycle of riparian wetlands in arid areas and ecological management and restoration of riparian wetlands in arid areas.

• The Grijalva–Usumacinta river system is the second freshwater input and an important source of nutrients for the Gulf of Mexico.
• Higher nutrient and chlorophyll concentrations were measured in the Grijalva River, as result of higher human pressures related to urbanization and agriculture.
• Seasonal patterns in discharge and nutrient concentration were stronger in the Usumacinta River, evincing the flow regulation in the Grijalva.
• The Usumacinta River showed higher nutrient load, although the Grijalva River transports more soluble reactive phosphorus and ammonium.

The combined biological-chemical clogging was closely related to the iron concentration. An iron water quality target in recharge water for MAR should be <0.3 mg/L to mitigate clogging effects.

A 3-year streambed flux dataset reveals substantial temporal variability at sub-daily, daily, and inter-annual timescales with implications for groundwater recharge and hyporheic exchange.

Fluvial acoustic tomography system was used to determine key streamflow characteristics (i.e., rainfall, backwater effects) based on a high temporal resolution of 10 min and long-term observations of streamflow in a mountainous river.

The annual evaporation from a subarctic reservoir was measured at 442 mm on average based on a 4-year eddy-covariance measurement campaign. This value was adjusted to 590 mm following the assessment of the associated energy balance, which revealed an underestimation of about 26% of the turbulent fluxes. More precisely, 84% of the total annual evaporation took place from August to December only when the atmosphere was mostly unstable. Moreover, the sensible heat flux was negative from January to July and peaked in December by 50% higher than the latent heat flux. Finally, evaporation was mainly controlled by wind speed and air humidity, whereas it did not seem to be affected by the duration of reservoir freeze-up.

Computed random fluxes into and out of the soil, $$$ r $$$, from the measured water content, $$$ \theta $$$, and hydraulic conductivity, $$$ {K}_0 $$$. The random influx is computed as an inverse problem using the methods based on random fractional partial differential equations presented in this paper. The methods have been applied to data from single site and a catchment.

To describe hydrological process knowledge in experimental watersheds, experts commonly use a ‘perceptual model’, a figure that illustrates the watershed and its runoff processes. We surveyed the literature and found 63 perceptual model figures, then analysed the information in each figure including counting and categorizing the stores and fluxes using a taxonomic classification. We evaluated and made recommendations for perceptual models as a method to share hydrological process information.

Open-surface water bodies are essential terrestrial water sources and ecosystem service providers. In Yellow River Basin, the second largest basin in China, open-surface water bodies have been increasing and the seasonal difference has been declining during 1990–2020 despite a decreasing discharge. Anthropogenic activity, for example water conservation projects contributed to this trend, ensuring water resource availability in this populated arid to semi-arid area.

We test a hypothesis that mass conservation constraints restrict a model's ability to compensate for disinformation from input data. Our results are presented generally in terms of constraints enforced on deep learning (DL) and conceptual model architecture. Our findings demonstrate:

• Conservation may not be a good foundation for watershed scale hydrological theory.
• Disinformative data is not generally a major source of modelling error.
• DL models compensate for systematic biases in the input data on a per-event basis.

To clarify the effect of vegetation lodging on overland flow, an indoor flume experiment of vegetation gradient lodging combination and lodging angle was carried out. The results show that it is reasonable to use a uniform lodging angle to simulate the influence of gradient lodging on the overland flow resistance. The influence of vegetation lodging angle on flow state changes and resistance mechanism is studied, and a calculation model of resistance coefficient of lodging vegetation in non-submerged state is established.

Using a numerical model, we simulate steady-state groundwater head at 1 km spatial resolution over entire England and Wales. The figure shows simulated groundwater table depth in metres below the land surface. Our results demonstrate that at a large spatial scale, mainly atmospheric forcing controls the spatial variability of groundwater head while at a smaller scale, the impacts of lateral flow are substantial.

Typhoon Lupit had significant fluctuations in δ¹⁸O values, exhibiting a three-stage variation characteristic with distinctly negative δ¹⁸O values in the second stage. The extremely negative δ¹⁸O values were because of accumulated convective activity and continuous precipitation as they travelled towards the centre of the typhoon.

This study demonstrated that the ‘amplifying effect’ of anthropogenic activities is significant when climate tends to become dry because more shallow groundwater pumping is expected to maintain regional water resources demand under dry climate in the region highly relying on groundwater.

Effects of preferential flow on air pressure in unsaturated zone and drawdown in saturated zone

The relationship between the nitrate retention with water fluxes and dissolve oxygen at the interface between surface water and groundwater.

The replacement of Eucalyptus regnans with Acacia dealbata forests under increasing fire frequencies would result in a significant decrease in annual and decadal Et, inferring a divergence in eco-hydrologic functions. The data suggest that significant divergence in forest structure, Et and water yield between E. regnans and A. dealbata forests.

The three wet ranges of soil hydraulics are most accurately described by the updated functions.

Ground-based thermal infrared (TIR) temperature can predict spatio-temporally continuous land surface energy balance. Proposed TIR methods showed good agreement with ground-based eddy covariance observations in turbulent heat fluxes for most cases. Predictability declined substantially as the fraction of senescent foliage increased in dry conditions.

Impacts of hydraulic infrastructures and contributions of the sub-basins on streamflow in the Vu Gia Thu Bon River basin, Vietnam

A data-driven approach based on the NASA GLDAS data is proposed for flood prediction with the assistance of the Gamma Test. A runoff generation model together with a routing model based on the LSTM network is established. The GLDAS meteorological data are used directly to simulate the streamflow at the catchment outlet by the integrated model.

Assessing ecological and socioeconomic impacts of ice-forming rivers across Europe, Asia and North America requires predictive capacity for related processes, including ice jam flooding. Using a physics-based breakup onset criterion, I develop and successfully test explicit expressions for the various components of the resistance of ice covers to mobilization, which partly controls breakup evolution and ice jam formation.