Event and seasonal hydrologic connectivity patterns  in an agricultural headwater catchment

Abstract. Connectivity of the hillslope and the stream is a non-stationary and non-linear phenomenon dependent on many controls. The objective of this study is to identify these controls by examining the spatial and temporal patterns of the similarity between shallow groundwater and soil moisture dynamics and streamflow dynamics in the Hydrological Open Air Laboratory (HOAL), a small (66 ha) agricultural headwater catchment in Lower Austria. We investigate the responses to 53 precipitation events and the seasonal dynamics of streamflow, groundwater and soil moisture over 2 years. The similarity, in terms of Spearman correlation coefficient, hysteresis index and peak-to-peak time, of groundwater to streamflow shows a clear spatial organization, which is best correlated with topographic position index, topographic wetness index and depth to the groundwater table. The similarity is greatest in the riparian zone and diminishes further away from the stream where the groundwater table is deeper. Soil moisture dynamics show high similarity to streamflow but no clear spatial pattern. This is reflected in a low correlation of the similarity with site characteristics. However, the similarity increases with increasing catchment wetness and rainfall duration. Groundwater connectivity to the stream on the seasonal scale is higher than that on the event scale, indicating that groundwater contributes more to the baseflow than to event runoff.

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Event and seasonal hydrologic connectivity patterns in an agricultural headwater catchment

10.5194/hess-2020-372 ◽

2020 ◽

Author(s):

Lovrenc Pavlin ◽

Borbála Széles ◽

Peter Strauss ◽

Alfred Paul Blaschke ◽

Günter Blöschl

Keyword(s):

Soil Moisture ◽

Shallow Groundwater ◽

Groundwater Table ◽

Peak Time ◽

Spatial And Temporal Patterns ◽

Topographic Wetness Index ◽

Event Scale ◽

Soil Moisture Dynamics ◽

Moisture Dynamics ◽

Headwater Catchment

Abstract. Connectivity of the hillslope and the stream is a non stationary and non linear phenomenon dependent on many controls. The objective of this study is to identify these controls by examining the spatial and temporal patterns of the similarity between shallow groundwater and soil moisture dynamics and streamflow dynamics in the Hydrological Open Air Laboratory (HOAL), a small (66 ha) agricultural headwater catchment in Lower Austria. We investigate the responses to 53 precipitation events and the seasonal dynamics of streamflow, groundwater and soil moisture over two years. The similarity, in terms of Spearman correlation coefficient, hysteresis index and peak-to-peak time, of groundwater to streamflow shows a clear spatial organisation, which is best correlated to topographic position index, topographic wetness index and depth to the groundwater table. The similarity is greatest in the riparian zone and diminishes further away from the stream where the groundwater table is deeper. Soil moisture dynamics show high similarity to streamflow but no clear spatial pattern. This is reflected in a low correlation of the similarity to site-characteristics, however, the similarity increases with increasing catchment wetness and rainfall duration. Groundwater connectivity to the stream on the seasonal scale is higher than that on the event scale indicating that groundwater contributes more to the baseflow than to event runoff.

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Modeling seasonal soil moisture dynamics in gley soils in relation to groundwater table oscillations in eastern Croatia

CATENA ◽

10.1016/j.catena.2021.105987 ◽

2022 ◽

Vol 211 ◽

pp. 105987

Author(s):

Vedran Krevh ◽

Vilim Filipović ◽

Lana Filipović ◽

Valentina Mateković ◽

Dragutin Petošić ◽

...

Keyword(s):

Soil Moisture ◽

Groundwater Table ◽

Soil Moisture Dynamics ◽

Moisture Dynamics

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Soil moisture dynamics and implications for irrigation of farmland with a deep groundwater table

Agricultural Water Management ◽

10.1016/j.agwat.2017.07.003 ◽

2017 ◽

Vol 192 ◽

pp. 138-148 ◽

Cited By ~ 7

Author(s):

Xudong Li ◽

Yong Zhao ◽

Weihua Xiao ◽

Mingzhi Yang ◽

Yanjun Shen ◽

...

Keyword(s):

Soil Moisture ◽

Groundwater Table ◽

Deep Groundwater ◽

Soil Moisture Dynamics ◽

Moisture Dynamics

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A dense network of cosmic-ray neutron sensors for soil moisture observation in a pre-alpine headwater catchment in Germany

10.5194/essd-2020-48 ◽

2020 ◽

Author(s):

Benjamin Fersch ◽

Till Francke ◽

Maik Heistermann ◽

Martin Schrön ◽

Veronika Döpper ◽

...

Keyword(s):

Soil Moisture ◽

Hydrological Modeling ◽

Root Zone ◽

Spatial Scales ◽

Cosmic Ray ◽

Dense Network ◽

Data Set ◽

Soil Moisture Dynamics ◽

Moisture Dynamics ◽

Headwater Catchment

Abstract. Monitoring soil moisture is still a challenge: it varies strongly in space and time and at various scales while well established sensors typically suffer from a small spatial support. With a sensor footprint up to several hectares, Cosmic-Ray Neutron Sensing (CRNS) is an emerging technology to address that challenge. So far, the CRNS method has typically been applied with single sensors or in sparse national scale networks. This study presents, for the first time, a dense network of 24 CRNS stations that covered, from May to July 2019, an area of just 1 km2: the pre-alpine Rott headwater catchment in Southern Germany which is characterized by strong soil moisture gradients in a heterogeneous landscape with forests and grasslands. With substantially overlapping sensor footprints, that network was designed to study root zone soil moisture dynamics at the catchment-scale. The observations of the dense CRNS network were complemented by extensive measurements that allow to study soil moisture variability at various spatial scales: roving (mobile) CRNS units, remotely sensed thermal images from Unmanned Areal Systems (UAS), permanent and temporary wireless sensor networks, profile probes as well as comprehensive manual soil sampling. Since neutron counts are also affected by hydrogen pools other than soil moisture, vegetation biomass was monitored in forest and grassland patches, as well as meteorological variables; discharge and groundwater tables were recorded to support hydrological modeling experiments. As a result, we provide a unique and comprehensive dataset to several research communities: to those who investigate the retrieval of soil moisture from cosmic-ray neutron sensing, to those who study the variability of soil moisture at different spatio-temporal scales, and to those who intend to better understand the role of root-zone soil moisture dynamics in the context of catchment and groundwater hydrology, as well as land – atmosphere exchange processes. The data set is available through EUDAT, splitted into the two subsets https://doi.org/10.23728/b2share.85fe0f9dac0f48df9215c17e65d1f1e1 (Fersch et al., 2020a) and https://doi.org/10.23728/b2share.93ed99e486904d48a8a6a68083066198 (Fersch et al., 2020b).

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A dense network of cosmic-ray neutron sensors for soil moisture observation in a highly instrumented pre-Alpine headwater catchment in Germany

Earth System Science Data ◽

10.5194/essd-12-2289-2020 ◽

2020 ◽

Vol 12 (3) ◽

pp. 2289-2309

Author(s):

Benjamin Fersch ◽

Till Francke ◽

Maik Heistermann ◽

Martin Schrön ◽

Veronika Döpper ◽

...

Keyword(s):

Soil Moisture ◽

Hydrological Modeling ◽

Root Zone ◽

Spatial Scales ◽

Cosmic Ray ◽

Dense Network ◽

Data Set ◽

Soil Moisture Dynamics ◽

Moisture Dynamics ◽

Headwater Catchment

Abstract. Monitoring soil moisture is still a challenge: it varies strongly in space and time and at various scales while conventional sensors typically suffer from small spatial support. With a sensor footprint up to several hectares, cosmic-ray neutron sensing (CRNS) is a modern technology to address that challenge. So far, the CRNS method has typically been applied with single sensors or in sparse national-scale networks. This study presents, for the first time, a dense network of 24 CRNS stations that covered, from May to July 2019, an area of just 1 km2: the pre-Alpine Rott headwater catchment in Southern Germany, which is characterized by strong soil moisture gradients in a heterogeneous landscape with forests and grasslands. With substantially overlapping sensor footprints, this network was designed to study root-zone soil moisture dynamics at the catchment scale. The observations of the dense CRNS network were complemented by extensive measurements that allow users to study soil moisture variability at various spatial scales: roving (mobile) CRNS units, remotely sensed thermal images from unmanned areal systems (UASs), permanent and temporary wireless sensor networks, profile probes, and comprehensive manual soil sampling. Since neutron counts are also affected by hydrogen pools other than soil moisture, vegetation biomass was monitored in forest and grassland patches, as well as meteorological variables; discharge and groundwater tables were recorded to support hydrological modeling experiments. As a result, we provide a unique and comprehensive data set to several research communities: to those who investigate the retrieval of soil moisture from cosmic-ray neutron sensing, to those who study the variability of soil moisture at different spatiotemporal scales, and to those who intend to better understand the role of root-zone soil moisture dynamics in the context of catchment and groundwater hydrology, as well as land–atmosphere exchange processes. The data set is available through the EUDAT Collaborative Data Infrastructure and is split into two subsets: https://doi.org/10.23728/b2share.282675586fb94f44ab2fd09da0856883 (Fersch et al., 2020a) and https://doi.org/10.23728/b2share.bd89f066c26a4507ad654e994153358b (Fersch et al., 2020b).

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