Characterization and drivers of water and carbon fluxes dynamics in dune ecosystems of the Horqin Sandy Land

Copyright © 2024. Published by Elsevier B.V..

Sandy regions constitute pivotal components of terrestrial ecosystems, exerting significant influences on global ecological equilibrium and security. This study meticulously explored water and carbon fluxes dynamics within a dune ecosystem in the Horqin Sandy Land throughout the growing seasons from 2013 to 2022 by employing an advanced eddy covariance system. The dynamic characteristics of these fluxes and their underlying driving forces were extensively analyzed, with a particular focus on the impact of precipitation. The main results are as follows: (1) During the growing seasons of 2015 and 2016, the dune ecosystem acted as a modest carbon source, while in 2013, 2014, and 2017- 2022, it transformed into a net carbon sink. Notably, the annual mean values of water use efficiency (WUE) and evapotranspiration (ET) were 5.16 gC·kg-1H2O and 255.4 mm, respectively. (2) The intensity, frequency, and temporal distribution of precipitation were found to significantly influence the carbon and water fluxes dynamics. Isolated minor precipitation events did not trigger substantial fluctuations, but substantial and prolonged precipitation events spanning multiple days or consecutive minor precipitation events resulted in notable assimilation delays. (3) Air temperature, soil temperature, and fractional vegetation cover (FVC) were found to be key factors influencing the carbon and water fluxes. Specifically, FVC exhibited a negative logarithmic correlation with net ecosystem CO2 exchange (NEE) and a power function relationship with WUE. (4) The interaction between carbon and water fluxes is exhibited by exponential increases in ecosystem respiration (Reco) and gross primary productivity (GPP) with WUE, while NEE displayed an exponential decrease in relation to WUE. These findings are of high significance in predicting the potential ramifications of climate change on the intricate carbon and water cycles, and enhance our understanding of ecosystem dynamics in sandy environments.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:918

Enthalten in:

The Science of the total environment - 918(2024) vom: 25. Feb., Seite 170517

Sprache:

Englisch

Beteiligte Personen:

Zhang, Simin [VerfasserIn]
Liu, Tingxi [VerfasserIn]
Duan, Limin [VerfasserIn]
Hao, Lina [VerfasserIn]
Tong, Xin [VerfasserIn]
Jia, Tianyu [VerfasserIn]
Li, Xia [VerfasserIn]
Lun, Shuo [VerfasserIn]

Links:

Volltext

Themen:

Carbon flux
Climate change
Horqin Sandy Land
Journal Article
Net ecosystem CO(2) exchange
Water use efficiency

Anmerkungen:

Date Revised 21.02.2024

published: Print-Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.1016/j.scitotenv.2024.170517

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM36813587X