Reply on RC2 DOI Creative Commons
Nurit Agam

Published: Aug. 7, 2023

Abstract. The mechanisms underlying the soil CO2 flux (Fs) in dry desert soils are not fully understood. To better understand these processes, we must accurately estimate small fluxes. most commonly used method, static chambers, inherently alter conditions that affect and may introduce errors of same order magnitude as itself. Regional global assessments annual respiration rates based on extrapolating point measurements conducted with chambers. Yet, studies ecosystems rarely discuss potential associated using chambers bare soils. We hypothesized a main source error is collar protrusion above surface. During 2021 season, deployed four automated collars different configurations Negev Desert, Israel. Fs exhibited repetitive diel cycle nocturnal uptake daytime efflux. measured over conventionally protruding was significantly lower than flushed Using thermal imaging, proved walls distorted ambient heating cooling regime topsoil layer, increasing mean surface temperatures. Higher temperatures during night suppressed driving forces, i.e., soil-atmosphere temperature gradients, ultimately leading to an underestimation up 50 % actual Fs. Accordingly, total daily by underestimated 35 %. This suggests larger carbon sink previously reported drylands, which cover approximately 40 Earth’s terrestrial surface, play significant role balance.

Language: Английский

Enriched stable hydrogen and oxygen isotopes in biocrusts unveil their critical roles in mediating ecohydrological processes of drylands DOI
Yousong Cao, Bo Xiao,

Fuhai Sun

et al.

Plant and Soil, Journal Year: 2025, Volume and Issue: unknown

Published: April 28, 2025

Language: Английский

Citations

0
Adhesion theory and model for air humidity impact on dust emission DOI Creative Commons
Yaping Shao

Aeolian Research, Journal Year: 2024, Volume and Issue: 66, P. 100898 - 100898

Published: Jan. 1, 2024

It has been suggested that air humidity influences dust emission under very dry conditions and adhesion might be the responsible process which changes binding between soil particles. The of is so far poorly understood difficult to quantify. Here, a critical examination relevant studies provided, an model proposed. Both isothermal-kinematic diffusion processes can limit liquid–water water–vapor exchange in soil, but for particle size range concerned aeolian studies, appears limiting process. shows moisture topsoil layers positively correlated with humidity, delays several hours. performance influenced by parameters particularly sensitive equilibrium content. This implies microscopic properties strongly influence adhesion. A new formulation water retention function covering entire also proposed, links pore distribution. Using relationship particle-size pore-size distributions, adhesion-affected grain estimated, defines upper particles moisture. study explains how through why low promotes finer

Language: Английский

Citations

3
Organic amendments from recycled waste promote short-term carbon sequestration of restored soils in drylands DOI
Rocío Soria, Natalia Rodríguez-Berbel, Enrique P. Sánchez‐Cañete

et al.

Journal of Environmental Management, Journal Year: 2022, Volume and Issue: 327, P. 116873 - 116873

Published: Dec. 2, 2022

Language: Английский

Citations

12
Interpretability of negative latent heat fluxes from eddy covariance measurements in dry conditions DOI Creative Commons
Sinikka Paulus, René Orth, Sung‐Ching Lee

et al.

Biogeosciences, Journal Year: 2024, Volume and Issue: 21(8), P. 2051 - 2085

Published: April 25, 2024

Abstract. It is known from arid and semi-arid ecosystems that atmospheric water vapor can directly be adsorbed by the soil matrix. Soil adsorption was typically neglected only recently received attention because of improvements in measurement techniques. One technique rarely explored for eddy covariance (EC). may detectable as downwardly directed (i.e., negative) EC latent heat (λE) flux measurements under dry conditions, but a systematic assessment use negative λE fluxes stations to characterize missing. We propose classification method adsorption, excluding conditions dew fog when derived not trustworthy due stable conditions. compare with weighing lysimeters 4 years Mediterranean savanna ecosystem 3 temperate agricultural site. Our aim assess if overnight inputs differ between how well they are EC. At site, measured each summer, whereas at much rarer predominantly an extreme drought event 2018. During 30 % nights 4-year period detected which 88.8 were confirmed least one lysimeter. recorded during 15 nights, 36.8 half hours matching simultaneous lysimeter adsorption. This relationship slightly improved 61 bare-soil droughts. underlines likely more relevant process compared ones able capture this difference. The comparisons amounts two methods revealed substantial underestimation lysimeters. was, however, comparable evaporation higher turbulence. Based on random-forest-based feature selection, we found mismatch being dominantly related site's inherent variability namely status, (surface) temperature. further demonstrate although very small mean values 0.04 or 0.06 mm per night lysimeter, respectively, it fraction diel balance Although instruments substantially regard ratio over 24 h 64 25 methods, either case substantial. Given usefulness detecting demonstrated here, there potential investigating climate regions thanks greater abundance observations.

Language: Английский

Citations

2
Seasonal precipitation distribution determines ecosystem CO2 and H2O exchange by regulating spring soil water–salt dynamics in a brackish wetland DOI
Wanxin Huang,

Guangxuan Han,

Siyu Wei

et al.

Functional Ecology, Journal Year: 2024, Volume and Issue: 38(9), P. 1959 - 1970

Published: July 14, 2024

Abstract The intensification of the global hydrological cycle is anticipated to increase variability precipitation patterns. Brackish wetlands respond changes in patterns by regulating absorption and release CO 2 H O maintain stability ecosystem functions. However, there limited understanding how inter‐seasonal distribution (SPD) affects exchange compared with annual totals. Here, we conducted four consecutive years field experiments a brackish wetland, manipulating proportion across different seasons while maintaining constant total. We utilized five inter‐SPD proportions (+73%, +56%, control (CK), −56%, −73%) examine effects SPD on exchange. Our findings revealed that fluxes showed trend decreasing decrease spring distribution. Among them, net exchange, evapotranspiration, carbon use efficiency water were shown be more sensitive summer autumn This negative asymmetric response pattern suggests primarily governed seasonal variability, soil water–salt dynamics identified as key driver. Therefore, this association can explained fact drought early growth stage exacerbates salinization inhibits vegetation colonization growth, thereby greatly impairing –H capacity wetlands. results emphasized extreme precipitation‐induced conditions will influence future. These are crucial for improving predictions sequestration water‐holding Read free Plain Language Summary article Journal blog.

Language: Английский

Citations

2
Effect of inappropriate solid waste on microplastic contamination in Balasore district and its aquatic environment DOI Creative Commons

Arun Kumar Mohanta,

Chittaranjan Sahoo, Rajkumar Jena

et al.

Bulletin of the National Research Centre/Bulletin of the National Research Center, Journal Year: 2024, Volume and Issue: 48(1)

Published: Nov. 24, 2024

Abstract Background Microplastic infection is now one of the world’s key environmental concerns. The most significant causes microplastic contamination in aquatic ecosystems are coastal villages, landfill sites, shipping activities and dumping areas. ingestion has been described an inclusive assortment from different trophic levels. This paper provides scientific evidence solid waste various sites Balasore district. Results village environment composite sand soils comprises numerous contaminants that have substantial effects on detection characterization results. Significant differences results ultraviolet–visible (UV–Vis) spectroscopy determine many pollutants possibly affected by aspects, including sampling instrumental settings. Inductively coupled plasma optical emission (ICP-OES) applied for first time to content wastes. In comparison with other techniques like Fourier transform infrared (FTIR) spectroscopy, it allows smaller microparticles. Microplastics wastes occur at variable size nm µm inductively suitable screening. addition, gas chromatography mass spectrometry (GCMS) becoming a valuable component analytical platforms monitoring plastic content. Scanning electron microscopy (SEM) imaging also detects shapes microplastics Conclusions Our study offers fresh perspectives critical areas further research as well how rural populations worldwide should be involved future studies pollution. presence led increased scrutiny calls regulation. Governments organizations exploring policies reduce mitigate its impacts human health.

Language: Английский

Citations

2
On the Influence of Thermal Stratification on Emitted Dust Flux DOI
Sylvain Dupont

Journal of Geophysical Research Atmospheres, Journal Year: 2022, Volume and Issue: 127(20)

Published: Oct. 7, 2022

Abstract The influence of the atmospheric boundary layer (ABL) stability on dust emitted from saltation is usually neglected. This has been challenged by two recent studies which suggested a dependency emission flux particle size distribution (PSD) to thermal stratification. Both observed enrichment in fine particles with instability but for different explanations: (a) larger eddy diffusivity submicron instability, and (b) an enhanced turbulence friction velocity u * stochasticity increasing bombardment fine‐dust emission. Here, we discuss investigate these propositions using WIND‐O‐V (WIND erOsion presence sparse Vegetation's) 2017 data set. We first show that explanation effect are questionable. We, then, second context ABL‐scale motions near‐surface instability. appears only possible at transition between windy free convection regimes where close its erosion threshold value. However, this intermediate regime more convective than event whom was proposed. Overall, our results no PSD. Instead, air relative humidity seem be main meteorological variables influencing particular, suggest may have affected surface soil moisture, thus interparticle cohesion, through water vapor adsorption.

Language: Английский

Citations

10
Patterns in biocrust recovery over time in semiarid southeast Spain DOI Creative Commons
Consuelo Rubio, Roberto Lázaro

Frontiers in Microbiology, Journal Year: 2023, Volume and Issue: 14

Published: June 15, 2023

Biological soil crusts (biocrusts) are communities of microorganisms, fungi, algae, lichens and mosses inhabiting on the surface within uppermost millimetres. They play an important ecological role in drylands, determining physical chemical properties reducing erosion. Studies biocrust natural recovery establish highly variable times. The different objectives methodologies experimentation analysis, strongly influence these predictions. main purpose this research is to analyze dynamics four their relationship with microclimatic variables. In 2004, Tabernas Desert, some us removed central 30 cm × area three 50 plots each (Cyanobacteria, Squamarina, Diploschistes, Lepraria), installing a station one sensors for temperature humidity air, dew point, PAR rain. Yearly, were photographed, cover every species was monitored 5 cell 36-cells grid covering area. We analyzed functions fit recovery, differences speed between communities, from spatial analysis plot, changes dissimilarity biodiversity possible relationships climatic fits sigmoidal function. community dominated by Cyanobacteria developed faster than those lichens. Squamarina Diploschistes recovered that Lepraria appears be influenced surrounding undisturbed areas. Species-based consecutive inventories fluctuated decreased over time, while increases similar way. community, along order which appeared, support hypothesis about succession, would include phases: firstly Cyanobacteria, then and/or finally Lepraria. microclimate complex work highlights need carry out further topic general.

Language: Английский

Citations

4
Study on the water-carbon coupling coordination function on the eastern edge of the Qinghai-Tibet plateau DOI

Xin Yuan,

Liang Jiao,

Xichen Che

et al.

Ecological Modelling, Journal Year: 2023, Volume and Issue: 487, P. 110572 - 110572

Published: Nov. 25, 2023

Language: Английский

Citations

4
Unravelling the main mechanism responsible for nocturnal CO2 uptake by dryland soils DOI Creative Commons
Minsu Kim, Clément López-Canfín, Roberto Lázaro

et al.

The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 926, P. 171751 - 171751

Published: March 17, 2024

Soil respiration, or CO2 efflux from soil, is a crucial component of the terrestrial carbon cycle in climate models. Contrastingly, many dryland soils absorb atmospheric at night, but exact mechanisms driving this uptake are actively debated. Here we used mechanistic model with heuristic approaches to unravel underlying processes observed patterns soil-atmosphere fluxes. We show that temperature drop during nighttime main driver by increasing solubility and local water pH thin film on soil particle surfaces, providing favourable conditions for carbonate precipitation. Our data demonstrate nocturnal inorganic absorption common process, often offset biological production. The rates can be impacted different successional stages biocrusts consume produce modify film, which maintained non-rainfall inputs, such as pore space condensation. Annual estimates uptake, based situ continuous measurements level drylands still very scarce, fluxes up several tens g C m−2 y−1 have been reported, potentially accounting considerable fraction global residual sink.

Language: Английский

Citations

1