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The Lancang-Mekong River significantly affects the livelihood of residents in the basin as well as the lives of people in other regions of the world in terms of great development potential and its economic and ecological values. In the meanwhile, the river attracts the attention of countries in the basin and the international community because it raises potential for international conflicts. The Lancang-Mekong River leaves China from Xishuangbanna and the ecosystem status in Xishuangbanna constitutes one of the top concerns related to the basin. The study comprehensively evaluates the status of freshwater ecosystem health of the Lancang River in Xishuangbanna for the first time, with reference to aspects of ecosystem vitality, ecosystem services, as well as governance and stakeholders, firstly, linking the ecosystem and the benefits it provides as well as human activities as an organic whole. The methodology used, Freshwater Health Index, is newly developed and constitutes revision of the first attempt of its usage. Basically, the freshwater ecosystem in the studied area and period remains healthy according to the research, and the ecosystem is considered to be capable of providing sufficient services and benefits to meet the economic and societal development demands. Recommendations are proposed for more sustainable local freshwater management and utilization accordingly.

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The International Reference Ionosphere (IRI) is an empirical model widely used to describe ionospheric characteristics. In the previous research, high-precision total ionospheric electron content (TEC) data derived from global navigation satellite system (GNSS) data were used to adjust the ionospheric global index IG12 used as a driving parameter in the standard IRI model; thus, the errors between IRI-TEC and GNSS-TEC were minimized, and IRI-TEC was calibrated by modifying IRI with the updated IG12 index (IG-up). This paper investigates various interpolation strategies for IG-up values calculated from GNSS reference stations and the calibrated TEC accuracy achieved using the modified IRI-2016 model with the interpolated IG-up values as driving parameters. Experimental results from 2015 and 2019 show that interpolating IG-up with a 2.5° × 5° spatial grid and a 1-h time resolution drives IRI-2016 to generate ionospheric TEC values consistent with GNSS-TEC. For 2015 and 2019, the mean absolute error (MAE) of the modified IRI-TEC is improved by 78.57% and 77.42%, respectively, and the root mean square error (RMSE) is improved by 78.79% and 77.14%, respectively. The corresponding correlations of the linear regression between GNSS-TEC and the modified IRI-TEC are 0.986 and 0.966, more than 0.2 higher than with the standard IRI-TEC.