{'fraction_non_alphanumeric': 0.014120667522464698, 'fraction_numerical': 0.0, 'mean_word_length': 5.336043360433604, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
A paradigm shift in stormflow predictions for active tectonic regions with large-magnitude storms: generalisation of catchment observations by hydraulic sensitivity analysis and insight into soil-layer evolution

In active tectonic regions with large-magnitude storms, it is still difficult to predict stormflow responses by distributed runoff models from the catchment proper- ties without a parameter calibration using observational data. This paper represents an attempt to address the problem. A review of observational studies showed that the storm- flow generation mechanism was heterogeneous and com- plex, but stormflow responses there were simply simulated by a single tank with a drainage hole when the stormflow- contribution area was spatially invariable due to the suffi- cient amount of rainfall supply. These results suggested such a quick inflow/outflow waveform transmission was derived from the creation of a hydraulic continuum under a quasi- steady state. General conditions necessary for the continuum creation were theoretically examined by a sensitivity analy- sis for a sloping soil layer. A new similarity framework using the Richards equation was developed for specifying the sen- sitivities of waveform transmission to topographic and soil properties. The sensitivity analysis showed that saturation- excess overland flow was generally produced from a soil layer without any macropore effect, whereas the transmis- sion was derived mainly from the vertical unsaturated flow instead of the downslope flow in a soil layer with a large drainage capacity originated from the macropore effect. Both were possible for the quick transmission, but a discussion on the soil-layer evolution process suggested that an inhibition of the overland flow due to a large drainage capacity played a key role, because a confinement of the water flow within the soil layer might be needed for the evolution against strong erosional forces in the geographical regions. The long history of its evolution may mediate a relationship between simple stormflow responses and complex catchment properties. As a result, an insight into this evolution process and an induc- tive evaluation of the dependences on catchment properties by comparative hydrology are highly encouraged to predict stormflow responses by distributed runoff models.