LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 7 of total 7

Search options

  1. Article: Groundwater recharge from heavy rainfall in the southwestern Lake Chad Basin: evidence from isotopic observations

    Goni, Ibrahim Baba / Taylor, Richard G. / Favreau, Guillaume / Shamsudduha, Mohammad / Nazoumou, Yahaya / Ngounou Ngatcha, Benjamin

    Hydrological sciences journal. 2021 June 11, v. 66, no. 8

    2021  

    Abstract: We examine groundwater recharge processes and their relationship to rainfall intensity in the semi-arid, southwestern Lake Chad Basin of Nigeria using a newly compiled database of stable isotope data (δ²H, δ¹⁸O) from groundwater and rainfall. δ¹⁸O ... ...

    Abstract We examine groundwater recharge processes and their relationship to rainfall intensity in the semi-arid, southwestern Lake Chad Basin of Nigeria using a newly compiled database of stable isotope data (δ²H, δ¹⁸O) from groundwater and rainfall. δ¹⁸O signatures in groundwater proximate to surface waters are enriched in ¹⁸O relative to regional rainfall and trace focused groundwater recharge from evaporated waters via ephemeral river discharge and Lake Chad; groundwater remote from river channels is comparatively depleted and associated with diffuse recharge, often via sand dunes. Stable isotope ratios of O and H (δ²H, δ¹⁸O) in groundwater samples regress to a value along the local meteoric waterline that is depleted relative to weighted mean composition of rainfall, consistent with rainfall exceeding the 60ᵗʰ percentile of monthly precipitation intensity. The observed bias in groundwater recharge to heavy monthly rainfall suggests that the intensification of tropical rainfall under global warming favours groundwater recharge in this basin.
    Keywords basins ; databases ; groundwater ; groundwater recharge ; rain ; rain intensity ; river flow ; rivers ; sand ; stable isotopes ; Lake Chad ; Nigeria
    Language English
    Dates of publication 2021-0611
    Size p. 1359-1371.
    Publishing place Taylor & Francis
    Document type Article
    ISSN 2150-3435
    DOI 10.1080/02626667.2021.1937630
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  2. Book ; Online: High-resolution long-term average groundwater recharge in Africa estimated using random forest regression and residual interpolation

    Pazola, Anna / Taylor, Richard G. / Shamsudduha, Mohammad / French, Jon / MacDonald, Alan M. / Abiye, Tamiru / Goni, Ibrahim Baba

    eISSN:

    2023  

    Abstract: Groundwater recharge is a key hydrogeological variable that informs the renewability of groundwater resources. Long-term average (LTA) groundwater recharge provides a measure of replenishment under the prevailing climatic and landuse conditions and is ... ...

    Abstract Groundwater recharge is a key hydrogeological variable that informs the renewability of groundwater resources. Long-term average (LTA) groundwater recharge provides a measure of replenishment under the prevailing climatic and landuse conditions and is therefore of considerable interest in assessing the sustainability of groundwater withdrawals globally. This study builds on the modelling results of MacDonald et al. (2021) who produced the first LTA groundwater recharge map across Africa using a linear mixed model (LMM) rooted in 134 ground-based studies. Here, continent-wide predictions of groundwater recharge were generated using Random Forest (RF) regression employing five variables (precipitation, potential evapotranspiration, soil moisture, NDVI and aridity index) at a higher spatial resolution (0.1° resolution) to explore whether an improved model might be achieved through machine learning. Through the development of a series of RF models, we confirm that a RF model is able to generate maps of higher spatial variability than LMM; the performance of final RF models in terms of the goodness of fit (R 2 = 0.83, 0.88 with residual kriging) is comparable to the LMM (R 2 = 0.86). The higher spatial scale of the predictor data (0.1°) in RF models better preserves small-scale variability from predictor data, than the values provided via interpolated LMM; these may provide useful in testing global-to-local scale models. The RF model remains, nevertheless, constrained by its representation of focused recharge and by the limited range of recharge studies in tropical Africa, especially in the areas of high precipitation. This confers substantial uncertainty in model estimates.
    Subject code 550 ; 333
    Language English
    Publishing date 2023-10-06
    Publishing country de
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  3. Article: Application of GRACE to the estimation of groundwater storage change in a data‐poor region: A case study of Ngadda catchment in the Lake Chad Basin

    Skaskevych, Alla / Lee, Jejung / Jung, Hahn Chul / Bolten, John / David, John L / Policelli, Frederick S / Goni, Ibrahim B / Favreau, Guillaume / San, Soma / Ichoku, Charles M

    Hydrological processes. 2020 Feb. 15, v. 34, no. 4

    2020  

    Abstract: The present study is to explore the feasibility of GRACE‐based estimation of a groundwater storage change in a data‐poor region using a case study of the Ngadda catchment in the Lake Chad Basin. Although the Ngadda catchment has only one set of in situ ... ...

    Abstract The present study is to explore the feasibility of GRACE‐based estimation of a groundwater storage change in a data‐poor region using a case study of the Ngadda catchment in the Lake Chad Basin. Although the Ngadda catchment has only one set of in situ time series data of groundwater from 2006 to 2009 and a limited number of groundwater measurements in 2005 and 2009, GRACE‐based groundwater storage change can be evaluated against the in situ groundwater measurements combined with specific yield data. The cross‐correlation analysis in the Ngadda catchment shows that maximum rainfall reached in July and August, whereas both the maximum total water storage anomaly and the maximum groundwater storage anomaly occurred 2months later. Whereas the mean annual amplitude of total water storage anomaly is about 17cm from both the average total water storage anomaly from three mascon products and the one from three spherical harmonic products, the mean annual amplitude of soil moisture storage anomaly is substantially varied from 5.58cm for CLM to about 14cm for NOAH and Mosaic. The goodness‐of‐fit tests show that CLM soil moisture produces the closest estimation of groundwater storage anomaly to the in situ groundwater measurements. The present study shows that GRACE‐based estimation for groundwater storage anomaly can be a cost‐effective and alternative tool to observe how groundwater changes in a basin scale under the limitation of modelling and in situ data availability.
    Keywords basins ; case studies ; cost effectiveness ; groundwater ; models ; rain ; soil water ; time series analysis ; water storage ; watersheds ; Lake Chad
    Language English
    Dates of publication 2020-0215
    Size p. 941-955.
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note JOURNAL ARTICLE
    ZDB-ID 1479953-4
    ISSN 1099-1085 ; 0885-6087
    ISSN (online) 1099-1085
    ISSN 0885-6087
    DOI 10.1002/hyp.13613
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  4. Article: Global GRACE Data Assimilation for Groundwater and Drought Monitoring: Advances and Challenges

    Li, Bailing / Rodell, Matthew / Kumar, Sujay / Beaudoing, Hiroko Kato / Getirana, Augusto / Zaitchik, Benjamin F. / de Goncalves, Luis Gustavo / Cossetin, Camila / Bhanja, Soumendra / Mukherjee, Abhijit / Tian, Siyuan / Tangdamrongsub, Natthachet / Long, Di / Nanteza, Jamiat / Lee, Jejung / Policelli, Frederick / Goni, Ibrahim B. / Daira, Djoret / Bila, Mohammed /
    de Lannoy, Gabriëlle / Mocko, David / Steele‐Dunne, Susan C. / Save, Himanshu / Bettadpur, Srinivas

    Water resources research. 2019 Sept., v. 55, no. 9

    2019  

    Abstract: The scarcity of groundwater storage change data at the global scale hinders our ability to monitor groundwater resources effectively. In this study, we assimilate a state‐of‐the‐art terrestrial water storage product derived from Gravity Recovery and ... ...

    Abstract The scarcity of groundwater storage change data at the global scale hinders our ability to monitor groundwater resources effectively. In this study, we assimilate a state‐of‐the‐art terrestrial water storage product derived from Gravity Recovery and Climate Experiment (GRACE) satellite observations into NASA's Catchment land surface model (CLSM) at the global scale, with the goal of generating groundwater storage time series that are useful for drought monitoring and other applications. Evaluation using in situ data from nearly 4,000 wells shows that GRACE data assimilation improves the simulation of groundwater, with estimation errors reduced by 36% and 10% and correlation improved by 16% and 22% at the regional and point scales, respectively. The biggest improvements are observed in regions with large interannual variability in precipitation, where simulated groundwater responds too strongly to changes in atmospheric forcing. The positive impacts of GRACE data assimilation are further demonstrated using observed low‐flow data. CLSM and GRACE data assimilation performance is also examined across different permeability categories. The evaluation reveals that GRACE data assimilation fails to compensate for the lack of a groundwater withdrawal scheme in CLSM when it comes to simulating realistic groundwater variations in regions with intensive groundwater abstraction. CLSM‐simulated groundwater correlates strongly with 12‐month precipitation anomalies in low‐latitude and midlatitude areas. A groundwater drought indicator based on GRACE data assimilation generally agrees with other regional‐scale drought indicators, with discrepancies mainly in their estimated drought severity.
    Keywords climate ; drought ; groundwater ; groundwater extraction ; latitude ; models ; permeability ; research ; satellites ; storage time ; time series analysis ; water storage ; watersheds
    Language English
    Dates of publication 2019-09
    Size p. 7564-7586.
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note JOURNAL ARTICLE
    ZDB-ID 5564-5
    ISSN 1944-7973 ; 0043-1397
    ISSN (online) 1944-7973
    ISSN 0043-1397
    DOI 10.1029/2018WR024618
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 4285: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  5. Article ; Online: Author Correction: Observed controls on resilience of groundwater to climate variability in sub-Saharan Africa.

    Cuthbert, Mark O / Taylor, Richard G / Favreau, Guillaume / Todd, Martin C / Shamsudduha, Mohammad / Villholth, Karen G / MacDonald, Alan M / Scanlon, Bridget R / Kotchoni, D O Valerie / Vouillamoz, Jean-Michel / Lawson, Fabrice M A / Adjomayi, Philippe Armand / Kashaigili, Japhet / Seddon, David / Sorensen, James P R / Ebrahim, Girma Yimer / Owor, Michael / Nyenje, Philip M / Nazoumou, Yahaya /
    Goni, Ibrahim / Ousmane, Boukari Issoufou / Sibanda, Tenant / Ascott, Matthew J / Macdonald, David M J / Agyekum, William / Koussoubé, Youssouf / Wanke, Heike / Kim, Hyungjun / Wada, Yoshihide / Lo, Min-Hui / Oki, Taikan / Kukuric, Neno

    Nature

    2020  Volume 588, Issue 7838, Page(s) E25

    Language English
    Publishing date 2020-12-02
    Publishing country England
    Document type Published Erratum
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/s41586-020-2985-2
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.A 26: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)
    Zs.MG 9: Show issues
    Zs.MO 244: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  6. Article ; Online: Observed controls on resilience of groundwater to climate variability in sub-Saharan Africa.

    Cuthbert, Mark O / Taylor, Richard G / Favreau, Guillaume / Todd, Martin C / Shamsudduha, Mohammad / Villholth, Karen G / MacDonald, Alan M / Scanlon, Bridget R / Kotchoni, D O Valerie / Vouillamoz, Jean-Michel / Lawson, Fabrice M A / Adjomayi, Philippe Armand / Kashaigili, Japhet / Seddon, David / Sorensen, James P R / Ebrahim, Girma Yimer / Owor, Michael / Nyenje, Philip M / Nazoumou, Yahaya /
    Goni, Ibrahim / Ousmane, Boukari Issoufou / Sibanda, Tenant / Ascott, Matthew J / Macdonald, David M J / Agyekum, William / Koussoubé, Youssouf / Wanke, Heike / Kim, Hyungjun / Wada, Yoshihide / Lo, Min-Hui / Oki, Taikan / Kukuric, Neno

    Nature

    2019  Volume 572, Issue 7768, Page(s) 230–234

    Abstract: Groundwater in sub-Saharan Africa supports livelihoods and poverty ... ...

    Abstract Groundwater in sub-Saharan Africa supports livelihoods and poverty alleviation
    MeSH term(s) Africa South of the Sahara ; Desert Climate ; Droughts/statistics & numerical data ; Groundwater/analysis ; Rain
    Language English
    Publishing date 2019-08-07
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/s41586-019-1441-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.A 26: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)
    Zs.MG 9: Show issues
    Zs.MO 244: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  7. Article ; Online: Observed controls on resilience of groundwater to climate variability in sub-Saharan Africa

    Cuthbert, Mark O. / Taylor, Richard G. / Favreau, Guillaume / Todd, Martin C. / Shamsudduha, Mohammad / Villholth, Karen G. / MacDonald, Alan M. / Scanlon, Bridget R. / Kotchoni, D.O. Valerie / Vouillamoz, Jean-Michel / Lawson, Fabrice M.A. / Adjomayi, Philippe Armand / Kashaigili, Japhet J. / Seddon, David / Sorensen, James P. R. / Ebrahim, Girma Yimer / Owor, Michael / Nyenje, Philip M. / Nazoumou, Yahaya /
    Goni, Ibrahim / Ousmane, Boukari Issoufou / Sibanda, Tenant / Ascott, Matthew J. / Macdonald, David M.J. / Agyekum, William / Koussoubé, Youssouf / Wanke, Heike / Kim, Hyungjun / Wada, Yoshihide / Lo, Min-Hui / Oki, Taikan / Kukuric, Neno

    Nature

    2019  

    Abstract: Groundwater in sub-Saharan Africa supports livelihoods and poverty alleviation1,2, maintains vital ecosystems, and strongly influences terrestrial water and energy budgets3. Yet the hydrological processes that govern groundwater recharge and ... ...

    Abstract Groundwater in sub-Saharan Africa supports livelihoods and poverty alleviation1,2, maintains vital ecosystems, and strongly influences terrestrial water and energy budgets3. Yet the hydrological processes that govern groundwater recharge and sustainability—and their sensitivity to climatic variability—are poorly constrained4,5. Given the absence of firm observational constraints, it remains to be seen whether model-based projections of decreased water resources in dry parts of the region4 are justified. Here we show, through analysis of multidecadal groundwater hydrographs across sub-Saharan Africa, that levels of aridity dictate the predominant recharge processes, whereas local hydrogeology influences the type and sensitivity of precipitation–recharge relationships. Recharge in some humid locations varies by as little as five per cent (by coefficient of variation) across a wide range of annual precipitation values. Other regions, by contrast, show roughly linear precipitation–recharge relationships, with precipitation thresholds (of roughly ten millimetres or less per day) governing the initiation of recharge. These thresholds tend to rise as aridity increases, and recharge in drylands is more episodic and increasingly dominated by focused recharge through losses from ephemeral overland flows. Extreme annual recharge is commonly associated with intense rainfall and flooding events, themselves often driven by large-scale climate controls. Intense precipitation, even during years of lower overall precipitation, produces some of the largest years of recharge in some dry subtropical locations. Our results therefore challenge the ‘high certainty’ consensus regarding decreasing water resources4 in such regions of sub-Saharan Africa. The potential resilience of groundwater to climate variability in many areas that is revealed by these precipitation–recharge relationships is essential for informing reliable predictions of climate-change impacts and adaptation strategies.
    Language English
    Publishing date 2019-08-16T13:22:19Z
    Publisher Springer
    Publishing country fr
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

To top