Assessing the long-term sustainability of the groundwater resources in the Bacchiglione basin (Veneto, Italy) with the Mann–Kendall test: suggestions for higher reliability

Acque Sotterranee

Andrea Rinaldo¹  Giulia Passadore²  Silvia Bertoldo³  Mara Meggiorin³  Andrea Sottani³ 

[1] Dipartimento di Ingegneria Civile, Edile e Ambientale, Università di Padova Laboratory of Echohydrology (ECHO/IIE/ENAC), École Polytechnique Fédérale de Lausanne;Dipartimento di Ingegneria Civile, Edile e Ambientale, Università di Padova;Sinergeo Srl – Vicenza;

关键词: Mann-Kendall test;    Sen’s slope estimator;    sustainability;    groundwater level;    Bacchiglione;   

DOI  :  10.7343/as-2021-499

来源: DOAJ

【 摘 要 】

The social, economic, and ecological importance of the aquifer system within the Bacchiglione basin (Veneto, IT) is noteworthy, and there is considerable disagreement among previous studies over its sustainable use. Investigating the long-term quantitative sustainability of the groundwater system, this study presents a statistical methodology that can be applied to similar cases. Using a combination of robust and widely used techniques, we apply the seasonal Mann–Kendall test and the Sen’s slope estimator to the recorded groundwater level timeseries. The analysis is carried out on a large and heterogeneous proprietary dataset gathering hourly groundwater level timeseries at 79 control points, acquired during the period 2005–2019. The test identifies significant decreasing trends for most of the available records, unlike previous studies on the quantitative status of the same resource which covered the domain investigated here for a slightly different period: 2000–2014. The present study questions the reason for such diverging results by focusing on the method’s accuracy. After carrying out a Fourier analysis on the longest available timeseries, for studies of groundwater status assessment this work suggests applying the Mann–Kendall test to timeseries longer than 20 years (because otherwise the analysis would be affected by interannual periodicities of the water cycle). A further analysis of two 60-year-long monthly timeseries between 1960 and 2020 supports the actual sustainable use of the groundwater resource, the past deployment of the groundwater resources notwithstanding. Results thus prove more reliable, and meaningful inferences on the longterm sustainability of the groundwater system are possible.

【 授权许可】

Unknown