Causal relationships of vegetation productivity with root zone water availability and atmospheric dryness at the catchment scale

<p>This study explores the causal relationships between catchment water availability, vapor pressure deficit, and gross primary productivity (GPP) across 341 catchments in the contiguous US. Seasonal climatic, hydrological, and vegetation characteristics were represented using the Horton index...

Full description

Saved in:
Bibliographic Details
Main Authors: G. W. Abeshu, H.-Y. Li, M. Shi, L. R. Leung
Format: Article
Language:English
Published: Copernicus Publications 2025-04-01
Series:Hydrology and Earth System Sciences
Online Access:https://hess.copernicus.org/articles/29/1847/2025/hess-29-1847-2025.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850214267251326976
author G. W. Abeshu
H.-Y. Li
M. Shi
L. R. Leung
author_facet G. W. Abeshu
H.-Y. Li
M. Shi
L. R. Leung
author_sort G. W. Abeshu
collection DOAJ
description <p>This study explores the causal relationships between catchment water availability, vapor pressure deficit, and gross primary productivity (GPP) across 341 catchments in the contiguous US. Seasonal climatic, hydrological, and vegetation characteristics were represented using the Horton index, ecological aridity index, evaporative fraction index, and carbon uptake efficiency. Statistical methods, including circularity statistics, correlation analysis, and causality tests, were employed to determine the complex interactions between catchment wetness, atmospheric dryness, and vegetation carbon uptake. The results revealed a maximum lag of 2 months in the intra-annual variability of catchment water supply–productivity and atmospheric water demand–productivity relationships, with hysteresis patterns varying with the catchment's hydrological characteristics. In catchments not permanently under water-limited or energy-limited conditions, vegetation experiences hydrological stress during the peak growing period, coinciding with the highest gross primary productivity and carbon uptake efficiency being out of phase with the Horton index and in phase with the evaporative fraction index. Causality analysis highlights strong temporal continuity in GPP seasonal characteristics, with a cause–effect relationship between catchment water supply, atmospheric demand, and vegetation productivity spanning a maximum of 2 months. These findings underscore the need for a comprehensive functional framework that integrates catchment water supply, atmospheric demand, and vegetation productivity to enhance our understanding and predictive capabilities with regard to ecosystem responses to climate change.</p>
format Article
id doaj-art-2fee982a02b34decbda8ae16cc141f03
institution OA Journals
issn 1027-5606
1607-7938
language English
publishDate 2025-04-01
publisher Copernicus Publications
record_format Article
series Hydrology and Earth System Sciences
spelling doaj-art-2fee982a02b34decbda8ae16cc141f032025-08-20T02:08:57ZengCopernicus PublicationsHydrology and Earth System Sciences1027-56061607-79382025-04-01291847186410.5194/hess-29-1847-2025Causal relationships of vegetation productivity with root zone water availability and atmospheric dryness at the catchment scaleG. W. Abeshu0H.-Y. Li1M. Shi2L. R. Leung3Department of Civil and Environmental Engineering, University of Houston, Houston, TX, USADepartment of Civil and Environmental Engineering, University of Houston, Houston, TX, USAPacific Northwest National Laboratory, Richland, WA, USAPacific Northwest National Laboratory, Richland, WA, USA<p>This study explores the causal relationships between catchment water availability, vapor pressure deficit, and gross primary productivity (GPP) across 341 catchments in the contiguous US. Seasonal climatic, hydrological, and vegetation characteristics were represented using the Horton index, ecological aridity index, evaporative fraction index, and carbon uptake efficiency. Statistical methods, including circularity statistics, correlation analysis, and causality tests, were employed to determine the complex interactions between catchment wetness, atmospheric dryness, and vegetation carbon uptake. The results revealed a maximum lag of 2 months in the intra-annual variability of catchment water supply–productivity and atmospheric water demand–productivity relationships, with hysteresis patterns varying with the catchment's hydrological characteristics. In catchments not permanently under water-limited or energy-limited conditions, vegetation experiences hydrological stress during the peak growing period, coinciding with the highest gross primary productivity and carbon uptake efficiency being out of phase with the Horton index and in phase with the evaporative fraction index. Causality analysis highlights strong temporal continuity in GPP seasonal characteristics, with a cause–effect relationship between catchment water supply, atmospheric demand, and vegetation productivity spanning a maximum of 2 months. These findings underscore the need for a comprehensive functional framework that integrates catchment water supply, atmospheric demand, and vegetation productivity to enhance our understanding and predictive capabilities with regard to ecosystem responses to climate change.</p>https://hess.copernicus.org/articles/29/1847/2025/hess-29-1847-2025.pdf
spellingShingle G. W. Abeshu
H.-Y. Li
M. Shi
L. R. Leung
Causal relationships of vegetation productivity with root zone water availability and atmospheric dryness at the catchment scale
Hydrology and Earth System Sciences
title Causal relationships of vegetation productivity with root zone water availability and atmospheric dryness at the catchment scale
title_full Causal relationships of vegetation productivity with root zone water availability and atmospheric dryness at the catchment scale
title_fullStr Causal relationships of vegetation productivity with root zone water availability and atmospheric dryness at the catchment scale
title_full_unstemmed Causal relationships of vegetation productivity with root zone water availability and atmospheric dryness at the catchment scale
title_short Causal relationships of vegetation productivity with root zone water availability and atmospheric dryness at the catchment scale
title_sort causal relationships of vegetation productivity with root zone water availability and atmospheric dryness at the catchment scale
url https://hess.copernicus.org/articles/29/1847/2025/hess-29-1847-2025.pdf
work_keys_str_mv AT gwabeshu causalrelationshipsofvegetationproductivitywithrootzonewateravailabilityandatmosphericdrynessatthecatchmentscale
AT hyli causalrelationshipsofvegetationproductivitywithrootzonewateravailabilityandatmosphericdrynessatthecatchmentscale
AT mshi causalrelationshipsofvegetationproductivitywithrootzonewateravailabilityandatmosphericdrynessatthecatchmentscale
AT lrleung causalrelationshipsofvegetationproductivitywithrootzonewateravailabilityandatmosphericdrynessatthecatchmentscale