A Brief Review of Random Forests for Water Scientists and Practitioners and Their Recent History in Water Resources

Water, Journal Year: 2019, Volume and Issue: 11(5), P. 910 - 910

Published: April 30, 2019

Random forests (RF) is a supervised machine learning algorithm, which has recently started to gain prominence in water resources applications. However, existing applications are generally restricted the implementation of Breiman’s original algorithm for regression and classification problems, while numerous developments could be also useful solving diverse practical problems sector. Here we popularize RF their variants practicing scientist, discuss related concepts techniques, have received less attention from science hydrologic communities. In doing so, review resources, highlight potential its variants, assess degree exploitation range Relevant implementations random forests, as well techniques R programming language, covered.

Language: Английский

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Soil dissolved organic carbon in terrestrial ecosystems: Global budget, spatial distribution and controls

Global Ecology and Biogeography, Journal Year: 2020, Volume and Issue: 29(12), P. 2159 - 2175

Published: Oct. 11, 2020

Abstract Aims Soil dissolved organic carbon (DOC) is a primary form of labile in terrestrial ecosystems, and therefore plays vital role soil cycling. This study aims to quantify the budgets DOC at biome global levels examine variations their environmental controls. Location Global. Time period 1981–2019. Methods We compiled dataset analysed concentration distribution across 10 biomes. Results Large are found among biomes space declines exponentially along depths. Tundra has highest 0–30 cm soils [453.75 (95% confidence interval: 324.95–633.5) mg/kg], whereas tropical temperate forests have relatively lower concentrations, ranging from 30.20 (24.78–36.80) 54.54 (49.77–59.77) mg/kg. generally accounts for < 1% total soils, contributes more than half 0–100 profile. Furthermore, primarily controlled by texture, moisture, carbon. Main conclusions A synthesis combined with an empirical model extrapolate profiles globe, estimated as 7.20 Pg C top 12.97 profile, respectively, considerable variation The strong texture control but weak (TOC) on suggest that investigation physical protection might need expand consider soils. maps serve benchmark validating land surface models estimating storage

Language: Английский

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Moisture transport and seasonal variations in the stable isotopic composition of rainfall in Central American and Andean Páramo during El Niño conditions (2015–2016)

Hydrological Processes, Journal Year: 2019, Volume and Issue: 33(13), P. 1802 - 1817

Published: March 13, 2019

Abstract High‐elevation tropical grassland systems, called Páramo, provide essential ecosystem services such as water storage and supply for surrounding lowland areas. Páramo systems are threatened by climate land use changes. Rainfall generation processes moisture transport pathways influencing precipitation in the poorly understood but needed to estimate impact of these changes, particularly during El Niño conditions, which largely affect hydrometeorological conditions regions. To fill this knowledge gap, we present a stable isotope analysis rainfall samples collected on daily weekly basis between January 2015 May 2016 strongest event recorded history (2014–2016) two regions Central America (Chirripó, Costa Rica) northern Andes (Cajas, south Ecuador). Isotopic compositions were used identify how (convective orographic) change seasonally at each study site. Hybrid Single Particle Lagrangian Integrated Trajectory model (HYSPLIT) air mass back trajectory was preferential Our results show strong influence north‐east trade winds from Caribbean Sea Chirripó South American low‐level jet Amazon forest Cajas. These contributions also related formation convective associated with passage Intertropical Convergence Zone over Rica Ecuador wetter seasons orographic transition drier seasons. findings baseline information further research applications isotopes tracers other montane ecosystems tropics.

Language: Английский

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Tracer‐Aided Modeling in the Low‐Relief, Wet‐Dry Tropics Suggests Water Ages and DOC Export Are Driven by Seasonal Wetlands and Deep Groundwater

Water Resources Research, Journal Year: 2020, Volume and Issue: 56(4)

Published: March 17, 2020

Abstract Our understanding of how wet‐dry tropical catchments process water and solutes remains limited. In this study, we attempt to gain dissolved organic carbon (DOC) transport, storage, mixing in a 126 km 2 catchment northern Australia. We developed coupled, tracer‐aided, conceptual rainfall‐runoff model (SAVTAM) that simultaneously calculates water, isotope, DOC‐based processes at daily time step. The semidistributed can account for the marked hydrological distinction between savanna woodlands adjacent seasonal wetlands. Using calibrated model, tracked fluxes derived age storages. Model output matched variability, controlled by rainfall, which switched on off flow pathways from wetlands ultimately perennial river. Such connectivity is modulated karst aquifer system continuously contributes older waters (decades century old) maintain relatively stable streamflow during dry season (average stream = 9.7 16.2 years). occur despite rapid, monsoon‐driven response. DOC were largely sourced wetland riparian forest transported order 1.9 t C −2 year −1 stream, was average 90% total simulated exports C·km ·year . conclude coupled simulation biogeochemistry necessary generate more complete picture functioning, particularly tropics.

Language: Английский

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Bridging the gap from hydrological to biogeochemical processes using tracer-aided hydrological models in a tropical montane ecosystem

Journal of Hydrology, Journal Year: 2023, Volume and Issue: 619, P. 129328 - 129328

Published: March 3, 2023

Language: Английский

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Water transport and tracer mixing in volcanic ash soils at a tropical hillslope: A wet layered sloping sponge

Hydrological Processes, Journal Year: 2020, Volume and Issue: 34(9), P. 2032 - 2047

Published: March 9, 2020

Abstract Andosol soils formed in volcanic ash provide key hydrological services montane environments. To unravel the subsurface water transport and tracer mixing these we conducted a detailed characterization of soil properties analyzed 3‐year data set sub‐hourly hydrometric weekly stable isotope collected at three locations along steep hillslope. A weakly developed (52–61 cm depth), highly organic andic (Ah) horizon overlaying mineral (C) was identified, both showing relatively similar flow dynamics Soil moisture observations Ah showed fast responding (few hours) “rooted” layer to depth 15 cm, overlying “perched” that remained near saturated year‐round. The formation latter results from high matter (33–42%) clay (29–31%) content an abrupt hydraulic conductivity reduction this with respect rooted above. Isotopic signatures revealed resides within for short periods, (2 weeks) perched (4 layer. reaction during rainfall events also observed C horizon, response times those These indicate despite layer, which helps sustain storage soil, vertical mobilization through entire profile occurs events. being result transmissivity potentials porous matrix Andosols, as evidenced by exponential shape retention curves subsequent horizons. findings demonstrate behavior resembles “layered sponge,” paths dominate.

Language: Английский

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Frontiers in páramo water resources research: A multidisciplinary assessment

The Science of The Total Environment, Journal Year: 2023, Volume and Issue: 892, P. 164373 - 164373

Published: May 25, 2023

Language: Английский

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A concerted research effort to advance the hydrological understanding of tropical páramos

Hydrological Processes, Journal Year: 2020, Volume and Issue: 34(24), P. 4609 - 4627

Published: Sept. 14, 2020

Abstract Páramos, a neotropical alpine grassland‐peatland biome of the northern Andes and Central America, play an essential role in regional global cycles water, carbon, nutrients. They act as water towers, delivering ecosystem services from high mountains down to Pacific, Caribbean, Amazon regions. Páramos are also widely recognized biodiversity climate change hot spots, yet they threatened by anthropogenic activities environmental changes. Despite their importance for security carbon storage, vulnerability human activities, only three decades ago, páramos were severely understudied. Increasing awareness need hydrological evidence guide sustainable management prompted action generating data filling long‐standing knowledge gaps. This has led remarkably successful increase scientific knowledge, induced strong interaction between scientific, policy, (local) communities. A combination well‐established innovative approaches been applied collection, processing, analysis. In this review, we provide short overview historical development research state hydrometeorology, flux dynamics, impacts, influence extreme events páramos. We then present emerging technologies hydrology resources discuss how converging science policy efforts have leveraged traditional new observational techniques generate base that can support conclude co‐evolution was able successfully cover different spatial temporal scales. Lastly, outline future directions showcase long‐term collection foster responsible conservation towers.

Language: Английский

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Land Use Effects on Organic Carbon in Andean Volcanic Ash Soils

Journal of Plant Nutrition and Soil Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 26, 2025

ABSTRACT Background Both organic carbon (OC) stocks and labile OC (LOC) fractions are important indicators of soil health sensitive to land use change. Aims To study the effects change on these in montane volcanic ash soils, a transect was surveyed northern Ecuador. Methods Samples were collected from 0–30, 30–60, 60–90 cm depth at two agricultural sites with different time cultivation three natural vegetation (tropical alpine grassland, páramo). LOC determined as cold hot water extractable (CWEOC HWEOC). Molar absorptivity 254 nm extracts qualitative measure. Results Total high páramo (51.3–60.2 kg C m −3 ) younger site (50.8 ; 20 years cultivation), but significantly lower (30.1 older (at least 100 cultivation); CWEOC (0.1%–0.7%) HWEOC (0.6%–4.1%) represented only small part OC. pools decreased increasing time, reflecting short‐term long‐term effects. In contrast, molar highest oldest (198–307 L mol −1 vs. 36–64 other sites), indicating that easily degradable depleted leaving compounds higher aromaticity. Conclusions The conversion into negatively affects health, indicated by reduced storage capacities contents.

Language: Английский

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A field, laboratory, and literature review evaluation of the water retention curve of volcanic ash soils: How well do standard laboratory methods reflect field conditions?

Hydrological Processes, Journal Year: 2020, Volume and Issue: 35(1)

Published: Dec. 16, 2020

Abstract Accurate determination of the water retention curve (WRC) a soil is essential for understanding and modelling subsurface hydrological, ecological, biogeochemical processes. Volcanic ash soils with andic properties (Andosols) are recognized as important providers ecological hydrological services in mountainous regions worldwide due to their large fraction small size particles (clay, silt, organic matter) that gives them an outstanding holding capacity. Previous comparative analyses situ (field) standard laboratory methods WRC Andosols showed contrasting results. Based on extensive analysis laboratory, experimental, field measured WRCs combination data extracted from published literature we show using sample volumes (≤300 cm 3 ) mimic these only partially. The results obtained by latter resemble portion wet range Andosols' (from saturation up −5 kPa, or pF 1.7), but overestimate substantially content higher matric potentials. This discrepancy occurs irrespective site‐specific land use cover, properties, applied method. disagreement limits our capacity infer correctly behaviour, illustrated through long‐term moisture potential experimental site tropical Andes. These findings imply reported past research should be used caution future focus determining allow obtaining correct characterization Andosols. For latter, set recommendations directions solve identified methodological issues proposed.

Language: Английский

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