Please cite this article in press as: Strehmel, A., et al., Field data-based implementation of land management and terraces on the catchment scale for an eco-hydrological modelling approach in the Three Gorges Region, China. Agric. Water Manage. (2015), http://dx.doi.org/10.1016/j.agwat.2015.10.007 ARTICLE IN PRESS G Model AGWAT-4301; No. of Pages 18 Agricultural Water Management xxx (2015) xxx–xxx Contents lists available at ScienceDirect Agricultural Water Management journal homepage: www.elsevier.com/locate/agwat Field data-based implementation of land management and terraces on the catchment scale for an eco-hydrological modelling approach in the Three Gorges Region, China Alexander Strehmel ∗ , Amy Jewett, Ronja Schuldt, Britta Schmalz, Nicola Fohrer University of Kiel, Institute for Natural Resource Conservation, Department of Hydrology and Water Resources Management, Kiel, Germany a r t i c l e i n f o Article history: Received 17 July 2015 Received in revised form 4 October 2015 Accepted 10 October 2015 Available online xxx Keywords: Land management Terraces Eco-hydrological modelling Best Management Practices Three Gorges Region a b s t r a c t In this study, an innovative method to generate spatially-distributed data sets on land management and terraces based on sparse field data for a steep-sloping catchment in the Three Gorges Region in China is introduced and tested using the eco-hydrological model SWAT. The generation of such data sets is necessary for the development and evaluation of Best Management Practices (BMP) towards a reduction of high inputs of sediment and nutrients in water bodies. It is hypothesized that the inclusion of land management as well as terraces in the eco-hydrological modelling approach are individually as well as combined able to increase the model efficiency regarding streamflow and sediment. The results of the study show that the field data sets on land management and terraces can be used to generate useful SWAT input data sets to represent management and conservation practices and the model results are plausible. The effect of land management and terraces on streamflow is identified to be rather small. At the same time a strong effect of the inclusion of the terrace dataset on sediment yields can be observed, which can be seen as an improvement of the process representation within the model. By introducing the new method the study contributes to an improved representation of land management and terraces in data- scarce study regions in eco-hydrological models. At the same time the study confirms the importance of the consideration of BMPs in eco-hydrological modelling, especially towards the representation of the dynamics of sediment and sediment-bound substances. © 2015 Elsevier B.V. All rights reserved. 1. Introduction & Motivation The damming of the Yangtze River by the Three Gorges Dam in Hubei Province in central China is causing a rapid land use change in the Three Gorges Reservoir Region (TGR) (Ye et al., 2009; Zhang et al., 2009; Seeber et al., 2010). These land use changes encompass the land reclamation for new agricultural areas, which is connected to a loss in natural forest and shrubland, as well as the construc- tion of infrastructure and settlements for the relocated population (McDonald et al., 2008; Zhang et al., 2009). While the steep-sloping topography of the area as well as its shallow and highly erodible soils already cause high erosion rates in the region (Schönbrodt- Stitt et al., 2012), the fast land use change is a major trigger for even higher soil losses installing new agricultural areas on steep ∗ Corresponding author at: University of Kiel, Institute for Natural Resource Conservation, Department of Hydrology and Water Resources Management, Kiel, Germany, Olshausenstraße 75, Kiel, Germany. E-mail address: astrehmel@hydrology.uni-kiel.de (A. Strehmel). hillsides, causing high inputs of sediment and particle-bound agro- chemicals into rivers, from where they are transported to the Three Gorges Reservoir (Seeber et al., 2010; Bieger et al., 2015a). This has severe negative effects on the water quality and ecology of the reservoir (Wang et al., 2010; Bergmann et al., 2012; Holbach et al., 2012), while at the same time fostering its sedimentation (Lu and Higgitt, 2001; Xu and Milliman, 2009). The development of suitable management strategies to mitigate high inputs of nutri- ents and sediment into the reservoir can be based on a sound eco-hydrological modelling approach, which has to consider the specific conditions of the region (Gassman et al., 2007; Bieger et al., 2015a). The model SWAT (Soil and Water Assessment Tool; Arnold et al., 1998) is a semi-distributed eco-hydrological model designed to assess the impacts of land use and climatic changes on water, sedi- ment and nutrient dynamics in large, complex catchments (Neitsch et al., 2011). It relies on the concept of Hydrological Response Units (HRUs), subunits of uniform land use, soil type and slope class, which are aggregated for every subbasin of the catchment. Due to the possibility to implement agricultural management as well as http://dx.doi.org/10.1016/j.agwat.2015.10.007 0378-3774/© 2015 Elsevier B.V. All rights reserved.