Abstract. Water dynamics in the unsaturated zone is one of the most important processes as it controls model precision. One of the limitations in using a catchment model based on a Richards' equation is the huge amount of parameters required to run the model. In this study, we investigate the effect of unsaturated flow conceptualization models on the dynamic response of an integrated distributed hydrological model, which are (1) Richards equation (simple parameterization RI2) (2) Two layer water balance model (TLM). The physically based distributed modelling system, MIKESHE is applied to the Skjern catchment with the objective to test and analyze the effect of using different models for unsaturated flow on the dynamic response of an integrated distributed hydrological model. Results from this study show that regarding peak discharge at the catchment outlet follows the TLM, RI2 sequence. Similar results were found for the discharge characteristics of the sub basin. The close agreement between the simulated results of the two models also indicates that the simple TLM model is more suitable than the complex Richard equation model at least for the condition of the Skjern catchment, while its weaknesses is not describing the groundwater dynamics well.
Abstract. To help improve our understanding of the nutrient dynamics at the interface between surface waters and groundwaters, particularly in the context of aquatic plant change, we analyzed total nitrogen (TN) and nitrate (NO 3 -N) data from experiments. We assessed the effects of aquatic plant, nitrogen (N) and phosphorus (P) loading, water level on N processing. Laboratory experiments were conducted by percolating vegetated cores containing natural sediment or technical sand with artificial ground water and with either high or low levels of nutrients. 1. The results show that the growth rates of Elodea and Myriophyllum in Laboratory experiments were significantly higher in seepage treatments compared to control treatments, and final plant mass was up to 62% higher than that for plants where seepage was excluded. In areas with high groundwater discharge, a strong positive correlation was found between groundwater seepage fluxes, growth rates, and final plant mass for Elodea and Myriophyllum.The growth of Elodea and Myriophyllum was also significantly affected by groundwater seepage, but to a lesser degree than Elodea and Myriophyllum. Laboratory experiments generally showed the same trend for both Elodea and Myriophyllum and the positive influence of seeping ground water was apparently related to increased inorganic carbon supply and, to a lesser degree, improved nutrient availability. 2. The nutrient uptake capacity of Myriophyllum verticillatum was higher than that of Elodea nuttallii; Plants control the diffusion flux of nutrients through absorption. under higher concentration of nitrogen source condition, The growth of aquatic plant was better and nutrient uptake capacity of aquatic plant was stronger. 3. Under the conditions of smaller particle size of sediments and greater thickness, hyporheic zone had better prevent and control effect of nitrogen and phosphorus nutrients transport in groundwater; Small particle size of deposit in hyporheic zone can reduce nutrient flux through adsorption and blocking effect, diffusion flux peak had been delied and decreased.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.