The Use of Global Datasets in the SWAT Model for Tropical Watershed with Limited Ground Data: A Case Study in Serayu Upper Catchment

在實況資料有限的情形下，於SWAT模式中應用全球資料集以分析熱帶流域：以印尼Serayu集水區上游為例

Nugroho Christanto ； Muhammad Anggri Setiawan ； Afid Nurkholis ； Junun Sartohadi ； Muhammad Pramono Hadi

《台灣水利》 68卷3期 (2020/09) Pp. 18-27

https://doi.org/10.6937/TWC.202009/PP_68(3).0002

摘要

Global datasets, such as SOILGRIDS and global weather are more accessible and precise. Recently, the use of global datasets has been increasingly common in hydrological research. This study was designed to evaluate the use of global datasets (global weather and SOILGRIDS) as an alternative input to support the lack of ground measurement station and ground data in a tropical watershed, Upper Serayu Watershed. A hydrological model, SWAT, was used to run a daily hydrological model. The results showed that the combination of Global Weather and SOILGRIDS as the model input produced RRMSE = 0.70, R^2 = 0.7, and PBIAS = 15.5. These figures suggest that this combination generates a model with excellent performance, except for NSE = 0.45 that indicates nearly satisfactory performance. The model created using ground measurement data showed a better performance, with NSE = 0.80, RRMSE = 0.42, R^2 = 0.82, and PBIAS = 9.7. In conclusion, global datasets create a hydrological model with slightly lower performance than the one generated by ground measurement. Nevertheless, the former has the potential as an alternative to the latter, especially in the circumstance of missing ground data. Based on the 2009-2013 simulation, the modeled flow discharges were close to the measured ones, suggesting that datasets from Global Weather and SOILGRIDS can adequately substitute for ground measurement data in estimating the streamflow of a tropical watershed, that is, Upper Serayu Watershed.

關鍵字

SWAT model ； Global datasets ； Water balance models ； Hydrology ； Tropical area

並列摘要

全球資料集，如SOILGRIDS和氣象合成模式，其相關數據如今更為精準且較容易取得。因此，在水文研究中使用全球資料集變得更為普遍。本研究旨在以印尼境內熱帶流域──Serayu上游流域為例，評估將全球資料集（全球氣象合成和SOILGRIDS）作為替代輸入資料的可行性，以此完善地面測量站以及實況資料的缺失。本文使用土壤水文評估（SWAT）模式進行每日水文模擬，結果顯示，全球氣象和SOILGRIDS這一輸入組合的結果為RRMSE=0.70，R^2=0.7，PBIAS=15.5，這組數據表明此種組合產生的模式為“表現出色＂，除了NSE=0.45呈現結果為“幾乎滿意＂。另一方面，使用了實況資料作為輸入數據的模式則呈現出更好的表現，其結果為NSE=0.80，RRMSE=0.42，R^2=0.82，PBIAS=9.7。總而言之，全球資料集的水文模式的表現略遜色於實況資料模式。然而，前者仍有一定的潛力能在後者短缺的情況下作為替代輸入數據。基於2009－2013的模擬中，模擬結果的流量與實測流量非常相近，而這一研究結果表明，在估算熱帶流域──Serayu上游流域的流量時，全球氣象合成和SOILGRIDS的資料集可以充分替代地面測量數據。

並列關鍵字

SWAT模式 ； 全球資料集 ； 水平衡模型 ； 水文學 ； 熱帶地區