000004152 001__ 4152
000004152 005__ 20190221073103.0
000004152 037__ $$aCTALK-2019-0100
000004152 100__ $$aDelforge, D.
000004152 245__ $$aHydrological connectivity from causal analysis of time series in the Lhomme Karst System, Belgium
000004152 260__ $$c2019
000004152 269__ $$c2019-04-08
000004152 520__ $$aThe hydrological behaviour of karstic systems is difficult to theorize holistically because of their specificheterogeneities leading to distinctive nonlinear processes. Karstified systems present great opportunities for fieldexploration and hydrogeological monitoring of the vadose zone through its network of caves and conduits. Theseunique but explorable environments are predisposed to an inductive scientific approach where transfer processesassociated with hydrological connections are directly inferred from the data.This is done conventionally using dye tracing from which connections and transfer times are undeniably revealed.However, single tests do not allow appreciating the dynamic character of the hydrological connections. Nowadays,several data analysis methods aim at the detection of causal relationships between time series allowing theinvestigation of dynamics and interactions. Some are designed for linear systems as the simple cross-correlationmethod or the Granger causality, while others are suitable for nonlinear interactions, such as the Convergent CrossMapping method.Here, these methods are applied in order to draw up causal maps and compare short-term (up to 2 days) interactionsin the Lhomme Karst System in Belgium. The Lhomme Karst System has been monitored since 2013 and manytime series are available: meteorological data, soil moisture, drip discharges in the caves, piezometric levels, andlocal gravimetric time series. In addition, dye tracing experiments revealing connections and characteristic transfertimes were conducted. The different causal maps are compared and causal interactions are appreciated throughthe current knowledge of the system and discussed in relation to the question: can we infer true hydrologicalconnections and processes from the empirical determination of causal relationships between hydrological timeseries?
000004152 536__ $$aFRIA/$$cFRIA/$$fFRIA
000004152 594__ $$aNO
000004152 6531_ $$aKarst
000004152 6531_ $$aRochefort
000004152 6531_ $$aCausal analysis
000004152 6531_ $$aNon-linear system
000004152 700__ $$aVan Camp, M.
000004152 700__ $$aVanclooster, M.
000004152 700__ $$aHallet, V.
000004152 700__ $$aKaufmann, O.
000004152 700__ $$aPoulain, A.
000004152 700__ $$aWatlet, A.
000004152 773__ $$tEGU, Vienna
000004152 8560_ $$fmichel.vancamp@observatoire.be
000004152 906__ $$aContributed
000004152 980__ $$aCTALKCONT