UAV‐Based Land Surface Temperatures and Vegetation Indices Explain and Predict Spatial Patterns of Soil Water Isotopes in a Tropical Dry Forest

Water Resources Research, Journal Year: 2025, Volume and Issue: 61(2)

Published: Feb. 1, 2025

Abstract The spatial variation of soil water isotopes (SWI)—representing the baseline for investigating root uptake (RWU) depths with stable isotope techniques—has rarely been investigated. Here, we use SWI depth profile sampling in combination unmanned aerial vehicle (UAV) based land surface temperature estimates and vegetation indices (VI) order to improving process understanding relationships between variability content patterns canopy status, represented form VI. We carried out a 10 profiles tropical dry forest. UAV data were collected analyzed obtain detailed characterization status. then performed statistical analysis VI temperatures values at different resolutions (3 cm–5 m). Best used generating isoscapes entire study area. Results suggest that are strongly mediated by parameters (VI). Various correlate across all depths. depend on ( R 2 0.66 δ 18 O 0.64 H). Strongest overall correlations found resolution 0.5 m. speculate this might be ideal spatially characterizing investigate RWU forest environments. Supporting analyses UAV‐based approaches future avenue representation credibility such studies.

Language: Английский

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Dry season plant water sourcing in contrasting tropical ecosystems of Costa Rica

Ecohydrology, Journal Year: 2023, Volume and Issue: 16(5)

Published: March 7, 2023

Abstract Tracer‐aided studies to understand plant water uptake sources and dynamics in tropical ecosystems are limited. Here, we report the analysis of dry season source patterns five unique Costa Rica across altitudinal (<150–3,400 m asl) latitudinal (Caribbean Pacific slopes) gradients: evergreen seasonal rainforests, cloud forest, Páramo forest. Soil samples were collected during 2021. Plant soil extractions conducted using centrifugation. Stem extracted volume stem total content calculated via gravimetric analysis. Water contributions estimated a Bayesian mixing model. Isotope ratios stems exhibited strong meteoric origin. Enrichment trends only detected cactus within forest ecosystem. profiles revealed nearly uniform isotopic profiles; however, depletion trend was observed ecosystem below 25 cm. More enriched compositions reported for volumes above ~20% ( adj. r 2 = 0.34, p < 0.01). The most prominent rainforest (74.0%), (86.4%) (66.0%) corresponded well‐mixed water. In ecosystem, recent rainfall produced by trade wind incursions resulted significant (61.9%), whereas mean annual precipitation (38.6%) baseflow (33.1%) dominant sources. latter highlights prevalence distinct between cold front (near‐surface storage) more moisture season, revealing ecohydrological processing previously unknown this region.

Language: Английский

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The importance of continental evaporation for precipitation in Colombia: A baseline combining observations from stable isotopes and modelling moisture trajectories

Hydrological Processes, Journal Year: 2022, Volume and Issue: 36(6)

Published: May 14, 2022

Abstract The hydroclimatology of Northern South America responds to the coupling between Pacific and Atlantic oceans, Amazon–Andes interactions, orographic barrier regional Andes. relative contributions oceanic terrestrial moisture sources have been mostly evaluated in modelling studies, with limited observational data for validation. We combine observations from stable isotopes precipitation output Lagrangian trajectory tracking model FLEXPART characterize contrast contribution (from Pacific) different regions continent) mean monthly Andes Caribbean Colombia. Our results indicate that most becoming rain region has an atmospheric residence time deviates commonly assumed 10 days. These times vary source sink 1 day case recycling more than days Andean originating Ocean. Common integration both all are order three 7 Most comes including same (>30% months), Orinoco River basin (up 28% April), northern Amazon 17% June, July, August); followed by individually considered Tropical 30% October, November December) North January). fact a significant proportion rainfall is recycled highlights water availability Colombia could potentially be altered current widespread pervasive changes vegetation cover. More generally, our highlight need assess hydrological consequences land cover change America, particularly country like where water, food, energy security depend directly on precipitation.

Language: Английский

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Hydrometeorological factors controlling the stable isotopic composition of precipitation in the highlands of south Ecuador

Journal of Hydrometeorology, Journal Year: 2022, Volume and Issue: unknown

Published: April 28, 2022

Abstract Knowledge about precipitation generation remains limited in the tropical Andes due to lack of water stable isotope (WSI) data. Therefore, we investigated key factors controlling isotopic composition Páramo highlands southern Ecuador using event-based (high frequency) WSI data collected between November 2017 and October 2018. Our results show that air masses reach study site preferentially from eastern flank through Amazon basin (73.2%), Orinoco plains (11.2%), Mato Grosso Massif (2.7%), whereas only a small proportion stems Pacific Ocean (12.9%). A combination local regional influences δ 18 O precipitation. Regional atmospheric features (Atlantic moisture, evapotranspiration over Forest, continental rain-out, altitudinal lapse rates) are what largely control meteoric composition. Local precipitation, temperature, fraction corresponding moderate heavy rainfalls also influencing ratios, highlighting importance localized convective at site. Contrary O, d -excess values showed little temporal variation could not be statistically linked or hydrometeorological features. The latter reveals large amounts recycled moisture contributes regardless season predominant trajectories east. findings will help improve isotope-based climatic models enhance paleoclimate reconstructions highlands.

Language: Английский

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Exploring Dissolved Organic Carbon Variations in a High Elevation Tropical Peatland Ecosystem: Cerro de la Muerte, Costa Rica

Frontiers in Water, Journal Year: 2022, Volume and Issue: 3

Published: Jan. 24, 2022

Tropical peatlands are distributed mainly in coastal lowlands; however high elevation regions exhibit a large prevalence of small and fragmented that mostly understudied. Artificial drainage to expand the area cattle farming, horticulture, urbanization is increasing carbon losses atmosphere streams worldwide. Here, we present an exploratory characterization dissolved optical properties ombrotrophic peat bogs Talamanca range Costa Rica, across altitudinal gradient (2,400–3,100 m a.s.l.) during rainy season. Dissolved organic matter (DOM) sources decomposition processes were evaluated light inorganic (DOC DIC), properties, major water chemistry. DOC concentrations ranged from 0.2 up 47.0 mg/L. DIC below 2 mg/L δ 13 C values indicated mixture between soil matter, CO water, lesser degree derived bacterial . Absolute fluorescence intensity humic-like peaks was 6–7 times greater than fresh-like all sites. Fluorescence peak ratios coupled with biological humification indexes point relative contribution recalcitrant soil-derived DOM. Excitation/Emission matrices denoted humic fulvic acids bogs, moderate intensities soluble microbial by-products-like aromatic protein at three Our data provides baseline underpin tropical dynamics peatlands.

Language: Английский

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Stable water isotopic composition and evaporation to inflow ratios for high-mountain tropical Ecuadorian lakes

Hydrological Sciences Journal, Journal Year: 2024, Volume and Issue: 69(11), P. 1523 - 1538

Published: Aug. 5, 2024

In this study, we explore the utility of stable isotopes water (δ2H and δ18O) as integrative proxies for evaporative condition in high-mountain tropical lakes using a set small Ecuadorian Cajas National Park. Specifically, (1) characterize variability isotopic composition across several varying size depth (2) determine evaporation fraction inflow these lakes. We have used Hydrocalculator tool estimation to (E/I) ratio. Results indicated that larger lower seasonal their compared with smaller Further, there was clear variation monthly E/I ratios estimated lakes, indicating likely plays some (albeit limited) role level experienced within year.

Language: Английский

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Tracking seasonal evaporation of arid Ebinur Lake, NW China: isotopic evidence

Environmental Earth Sciences, Journal Year: 2024, Volume and Issue: 83(18)

Published: Sept. 1, 2024

Language: Английский

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Tracer‐aided modelling reveals quick runoff generation and young streamflow ages in a tropical rainforest catchment

Hydrological Processes, Journal Year: 2022, Volume and Issue: 36(2)

Published: Feb. 1, 2022

Abstract There is still limited understanding of where stream water originates, their flow paths, how sources mix, and for long transits montane tropical catchments. Here, we used a simple gamma convolution integral model (GM), ensemble hydrograph separation (EHS) tracer‐aided (TAM) to assess runoff generation, mixing processes ages in the pristine rainforest Quebrada Grande catchment Costa Rica. Model simulations are based on four‐year record (2016–2019) continuous hydrometric stable isotope observations. Comparative tests included multi‐objective calibration (2017–2019) validation (2016) using discharge data as well an independent evaluation groundwater soil data. GM TAM agreed dominance young streamflow that was less than 95 days old 75% study period. The EHS suggested fraction threshold 12 ± 2 with transit time distribution approximates best‐fit GM. These short result high annual rainfall even during drier years such 2019 4300 mm/a consistent quick near‐surface generation mixing. A supra‐regional loss (~55%) likely older detected. TAM‐based (streamflow KGE > 0.78, δ H 0.90) average contribution more 60% emphasizing paths. This represents one quickest responses mostly catchments globally.

Language: Английский

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Vapor Isotope Probing of Typhoons Invading the Taiwan Region in 2016

Journal of Geophysical Research Atmospheres, Journal Year: 2022, Volume and Issue: 127(21)

Published: Oct. 18, 2022

Abstract Every year, several typhoons originating from the West Pacific come close to Taiwan, modulating regional weather through intense rainfall and enhanced humidity. The isotopic ratios (δ 18 O δD) in typhoon vapor evolve along its track due rainout, recycling, replenishment. In 2016, this signature was recorded Taipei as vapors invaded local atmosphere. After disintegration, isotope of atmosphere slowly return background value. fall rise give a V‐shaped variation. processes controlling (like moisture turnover, speed, wind direction) are fast (1–2 days). contrast, recovery is slow (several days) depending on replacement rate atmospheric by incoming oceanic vapor. An evolution model based Rayleigh condensation box mixing phase proposed employed explain V‐shape. combination these two models for four major (Nepartak, Megi, Meranti, Malakas) shows agreement with observations. suggests that precipitation efficiency, PE (rainfall/overhead moisture), size important parameters decrease ratio. characteristic turnover time (inverse PE, obtained European Centre Medium‐Range Weather Forecasts fifth Re‐Analysis data) estimated be ∼2 days 500 km radius. Our study provides constraints budget typhoons.

Language: Английский

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Tracing isotope precipitation patterns across Mexico

PLOS Water, Journal Year: 2023, Volume and Issue: 2(10), P. e0000136 - e0000136

Published: Oct. 11, 2023

Mexico encompasses a large spectrum of landscapes with topographic, geographic, and climatic factors interacting in complex ecohydrological setting. For decades, isotope hydrogeological tools have been applied using short-term or seasonal local meteoric water lines as valid input functions. Yet, systematic evaluation characteristics is still lacking. Here we report on the spatial temporal variations 21 precipitation monitoring stations across Mexico. Our database includes 608 monthly samples collected from 2018 to 2021 over four regions (between 5 2,365 m asl): Pacific coast, Gulf Mexico/Caribbean Sea region, Central Northern plateaus. Precipitation δ 18 O seasonality dry (winter) wet season (summer) was characterized by notable W-shaped variability. Monthly amounts compositions exhibited poor strong linear regressions ( Adj . r 2 <0.01 0.75), inverse (positive) relationships northern monsoon-affected region. Low d -excess (5.1 9.7‰) corresponded greater terrestrial moisture contributions (20.5%) arid regions. Moisture inputs Ocean were associated near-equilibrium values (8.8 14.3‰), respectively. The best-fit models for = 0.85) H 0.88) determined topographic geographical predictors, resulting an updated high-resolution isoscape (100 grid) Orographic barriers (-2.10‰ O/km) coupled interaction tropical cyclones cold fronts, evolution North American Monsoon system, passage easterly trade winds play remarkable role controlling rainfall findings provide robust baseline ecohydrological, climatic, forensic, archeological, paleoclimate studies America.

Language: Английский

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