Do Land Use Changes Balance out Sediment Yields under Climate Change Predictions on the Sub-Basin Scale? The Carpathian Basin as an Example

Abstract

The issue of whether land use changes will balance out sediment yields induced by climate predictions was assessed for a Carpathian basin (Raba River, Poland). This discussion was based on the Macromodel DNS (Discharge–Nutrient–Sea)/SWAT (Soil and Water Assessment Tool) results for the RCP 4.5 and RCP 8.5 scenarios and LU predictions. To track sediment yield responses on the sub-basin level the studied area was divided into 36 units. The response of individual sub-basins to climate scenarios created a mosaic of negative and positive sediment yield changes in comparison to the baseline scenario. Then, overlapped forest and agricultural areas change indicated those sub-basins where sediment yields could be balanced out or not. The model revealed that sediment yields could be altered even by 49% in the selected upper sub-basins during the spring-summer months, while for the lower sub-basins the predicted changes will be less effective (3% on average). Moreover, the winter period, which needs to be re-defined due to an exceptional occurrence of frost and snow cover protecting soils against erosion, will significantly alter the soil particle transfer among the seasons. Finally, it has been shown that modeling of sediment transport, based on averaged meteorological values and LU changes, can lead to significant errors.

From the source to the reservoir and beyond—tracking sediment particles with modeling tools under climate change predictions (Carpathian Mts.)

“…To achieve the goal of the study, i.e., to track sediment particles from their source to the deposition area, the DNS (Discharge Nutrient Sea) digital platform (Macromodel DNS) has been used as a modeling tool. The Macromodel DNS, developed at the Institute of Meteorology and Water Management-National Research Institute (Instytut Meteorologii i Gospodarki Wodnej-Państwowy Instytut Badawczy, IMGW-PIB) (Wilk et al 2018b;Wilk and Orlińska-Woźniak 2019), provides an interactive platform allowing for integration of the SWAT (Soil and Water Assessment Tool) module (version 2012) (Arnold et al 2012;Abbaspour et al 2015) with other modeling tools (modules) to track different processes of the sediment/contaminant transport in a catchment (Wilk et al 2018a;Szalińska et al 2020Szalińska et al , 2021Orlińska-Woźniak et al 2020a). The RR catchment module has been created in the SWAT module (Fig.…”

“…1) with the use of flow data obtained from the IMGW-PIB (IMGW 2021), and total suspended sediment concentrations from the Polish State Monitoring System (PSMS 2021). Due to the fact that the state monitoring frequency is relatively low (12 times per year), the LOAD ESTimator program (LOADEST) was used to assist in development of the regression model for reliable estimation of constituent load (calibration), which has already been described in detail (Orlińska-Woźniak et al 2020a;Szalińska et al 2020). Model validation was performed for one of the Raba River right-bank tributaries (Fig.…”

“…Moreover, the forecasted changes in precipitation and temperature suggest that the intensity of this phenomenon may increase significantly (Borrelli et al 2020;Gianinetto et al 2020;Szalińska et al 2020). It also turns out that in such areas, even favorable changes in land use (LU) associated with a significant increase in the area of forests, which naturally stabilize the soil, may turn out to be insufficient to stop the negative effects of the climate changes (Orlińska-Woźniak et al 2020a).…”

“…The developed tool was used for the mountain catchment of the upper Raba River, located in the Polish part of the Carpathian Mountains, and flowing into the Dobczyce Reservoir. This area is distinguished by intensity of meteorological phenomena and water erosion (Mikuś et al 2019;Orlińska-Woźniak et al 2020a;Szalińska et al 2020). Moreover, land use forecasts indicate a gradual increase in forest cover in this area (Kozak et al 2017;Price et al 2017).…”

Biomass Production Potential in a River under Climate Change Scenarios

“…Concomitantly occuring anthropogenic and climate pressures exerted on river system are increasing, ,− and therefore a so-called “new wave of eutrophication” is frequently reported. , This phenomenon is mainly caused by human activity, more specifically by growing demand for food production, leading to intensification of agriculture, and an increase in nitrogen and phosphorus loads from nonpoint sources. This also includes a dynamic development of urbanized areas and an increase in industrial and municipal wastewater discharges.…”