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1.
Environ Geochem Health ; 46(7): 239, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849593

RESUMEN

The Ras Elma region, situated to the south of the city of Taza in northern Morocco, boasts abundant travertine formations that continue to develop, albeit selectively in specific sheltered sites. This development is influenced by various parameters, including the role of water chemistry. This article presents a spatio-temporal analysis of various hydrochemical parameters, including conductivity, pH, temperature, magnesium, calcium, and others. It's worth noting that the water from the Ras Elma Vauclusian spring, a key driver of travertinization in the region, is sourced from water infiltrating through faults and flowing into Lake Tompraire, known as Dayat Chikker near the Bab Boudir area. The findings suggest that the water in Ras Elma has turned aggressive, as revealed by the examination of the calcaro-carbonic equilibrium. CaCO3 precipitation occurs predominantly in the summer, significantly impacting the formation of travertines, particularly those of the spring and dam types. However, valley-type travertines exhibit more extensive development compared to the other two types.


Asunto(s)
Temperatura , Marruecos , Monitoreo del Ambiente , Concentración de Iones de Hidrógeno , Calcio/análisis , Manantiales Naturales/química , Magnesio/análisis , Magnesio/química , Estaciones del Año , Carbonato de Calcio/química , Lagos/química
2.
Environ Monit Assess ; 196(7): 624, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884659

RESUMEN

Effectively managing water resources in karst systems requires a thorough understanding of their general conduit network along with their seasonal dynamics. Their investigation has involved well construction or several advanced natural tracer data, most of which are not always available. Hence, this work showcases a pragmatic approach that makes use of basic hydrochemical variables of springs with coarse temporal resolution in characterising a karst system. In this study's example, physicochemical variables like major ion concentrations/ratios, Electrical Conductivity (EC), pH and water temperature (Tw) were measured on 20-day basis for a hydrological year at the Louros Catchment, Greece. We further performed the frequency distribution and variation analysis of EC and Tw, principal component analysis (PCA), scatter plots of carbonate ions vs sulphate and hydrochemographs to determine relevant hydrochemical processes and hydrogeological features. PCA and the scatter plots showed that the simple-type upper karst level is entirely dominated by carbonate dissolution, whereas the complex-type middle and lower levels also involve gypsum and dolomite dissolution. Presence of mixing between karst units was also detected. EC and Tw analyses revealed the degree of karstification of different units and relative depths of flow systems. Hydrochemographs reflected the seasonality of limestone and gypsum dissolution's contributions linked to the dominant flow type (conduit vs diffuse). This study thus was able to demonstrate the usefulness of such holistic hydrochemical analyses to better understand karst systems. Given their cost-effectiveness, they can be easily applied to any understudied karst system worldwide.


Asunto(s)
Monitoreo del Ambiente , Grecia , Manantiales Naturales/química , Estaciones del Año , Hidrología , Movimientos del Agua , Contaminantes Químicos del Agua/análisis
3.
Environ Geochem Health ; 46(6): 203, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38695991

RESUMEN

Manganese (Mn) is of particular concern in groundwater, as low-level chronic exposure to aqueous Mn concentrations in drinking water can result in a variety of health and neurodevelopmental effects. Much of the global population relies on drinking water sourced from karst aquifers. Thus, we seek to assess the relative risk of Mn contamination in karst by investigating the Shenandoah Valley, VA region, as it is underlain by both karst and non-karst aquifers and much of the population relies on water wells and spring water. Water and soil samples were collected throughout the Shenandoah Valley, to supplement pre-existing well water and spring data from the National Water Information System and the Virginia Household Water Quality Program, totaling 1815 wells and 119 springs. Soils were analyzed using X-ray fluorescence and Mn K-Edge X-ray absorption near-edge structure spectroscopy. Factors such as soil type, soil geochemistry, and aquifer lithology were linked with each location to determine if correlations exist with aqueous Mn concentrations. Analyzing the distribution of Mn in drinking water sources suggests that water wells and springs within karst aquifers are preferable with respect to chronic Mn exposure, with < 4.9% of wells and springs in dolostone and limestone aquifers exceeding 100 ppb Mn, while sandstone and shale aquifers have a heightened risk, with > 20% of wells exceeding 100 ppb Mn. The geochemistry of associated soils and spatial relationships to various hydrologic and geologic features indicates that water interactions with aquifer lithology and soils contribute to aqueous Mn concentrations. Relationships between aqueous Mn in spring waters and Mn in soils indicate that increasing aqueous Mn is correlated with decreasing soil Mn(IV). These results point to redox conditions exerting a dominant control on Mn in this region.


Asunto(s)
Agua Subterránea , Manganeso , Oxidación-Reducción , Suelo , Contaminantes Químicos del Agua , Pozos de Agua , Manganeso/análisis , Agua Subterránea/química , Contaminantes Químicos del Agua/análisis , Suelo/química , Manantiales Naturales/química , Monitoreo del Ambiente , Agua Potable/química , Contaminantes del Suelo/análisis , Contaminantes del Suelo/química , Espectrometría por Rayos X , Exposición a Riesgos Ambientales
4.
PLoS One ; 19(3): e0299532, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38451953

RESUMEN

Radon springs, characterized by their high concentrations of radon gas (Rn222), are extreme environments with unique physicochemical conditions distinct from conventional aquatic ecosystems. Our research aimed to investigate microbial life in radon springs, focusing on isolating extremophilic bacteria and assessing their resistance to adverse conditions. Our study revealed the prevalence of Actinomycetia species in the radon spring environment. We conducted various tests to evaluate the resistance of these isolates to oxidative stress, irradiation, desiccation, and metal ion content. These extremophilic bacteria showed overall higher resistance to these stresses compared to control strains. Lipidomic analysis was also employed to provide insights into the adaptive mechanisms of these bacteria which were found mainly in the correlations among individual clusters and changes in content of fatty acids (FA) as well as differences between content and type of FAs of environmental isolates and type strains.


Asunto(s)
Manantiales de Aguas Termales , Manantiales Naturales , Radón , Radón/análisis , Ecosistema , Bacterias , Manantiales de Aguas Termales/microbiología
5.
Glob Chang Biol ; 30(1): e16997, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37937346

RESUMEN

Mediterranean spring ecosystems are unique habitats at the interface between surface water and groundwater. These ecosystems support a remarkable array of biodiversity and provide important ecological functions and ecosystem services. Spring ecosystems are influenced by abiotic, biotic, and anthropogenic factors such as the lithology of their draining aquifers, their climate, and the land use of their recharge area, all of which affect the water chemistry of the aquifer and the spring discharges. One of the most relevant characteristics of spring ecosystems is the temporal stability of environmental conditions, including physicochemical features of the spring water, across seasons and years. This stability allows a wide range of species to benefit from these ecosystems (particularly during dry periods), fostering an unusually high number of endemic species. However, global change poses important threats to these freshwater ecosystems. Changes in temperature, evapotranspiration, and precipitation patterns can alter the water balance and chemistry of spring water. Eutrophication due to agricultural practices and emergent pollutants, such as pharmaceuticals, personal care products, and pesticides, is also a growing concern for the preservation of spring biodiversity. Here, we provide a synthesis of the main characteristics and functioning of Mediterranean spring ecosystems. We then describe their ecological value and biodiversity patterns and highlight the main risks these ecosystems face. Moreover, we identify existing knowledge gaps to guide future research in order to fully uncover the hidden biodiversity within these habitats and understand the main drivers that govern them. Finally, we provide a brief summary of recommended actions that should be taken to effectively manage and preserve Mediterranean spring ecosystems for future generations. Even though studies on Mediterranean spring ecosystems are still scarce, our review shows there are sufficient data to conclude that their future viability as functional ecosystems is under severe threat.


Asunto(s)
Ecosistema , Manantiales Naturales , Refugio de Fauna , Biodiversidad , Agua
6.
J Water Health ; 21(11): 1735-1740, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38017603

RESUMEN

Acanthamoebae spp. is considered highly adaptive. The present study aims to establish the occurrence of free-living amoebae, particularly Acanthamoebae, to exist in extreme environments such as volcanic mud springs. Fifty surface water samples were collected from mud springs (34 samples), and flat rocks (16 samples) were collected, processed, and cultured. After 14 days of incubation, 32 (64%) plates showed positive amoebic growth. Nineteen (55.8%) of these plates came from the mud spring collection site, while 13 (81.2%) samples are from flat rock sources. DNAs from positive samples were made to react to polymerase chain reaction (PCR) using primer sets JDP1 5'GGCCCAGATCGTTTACCGTGAA-3' and JDP2 5'TCTCACAAGCTGCTAGGGAGTCA-3' for cells that resemble Acanthamoebae. Sequencing and basic local alignment search tool (BLAST) revealed a 99% similarity of isolates to Acanthamoebae spp. Identification of Acanthamoebae spp that can survive in higher temperatures is important public health information. The existence of such isolates in the environment has dire health implications, which suggests revisitation of water treatment protocols. Detection of such organisms in environmental sources used for recreational purposes provides information to local and international tourists who frequent them. This will result in the mitigation of potential future infection.


Asunto(s)
Acanthamoeba , Amoeba , Manantiales Naturales , Filipinas , Reacción en Cadena de la Polimerasa
7.
Environ Monit Assess ; 195(8): 949, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37450062

RESUMEN

Natural springs are the main source of water supply for domestic and agricultural use for humans living in the mountainous regions of Asia. Increasing anthropogenic activities with associated waste load, coupled with inadequate sanitation, and contamination of natural water resources and the environment are emerging as important public health issues. We performed a prospective microbiological and physicochemical investigation of water samples from seven distinct natural springs situated at an altitude of 1615 m in the Bhaderwah region of Jammu and Kashmir, India. Bacterial groups belonging to opportunistic pathogens such as members of Moraxellaceae (Acinetobacter), Arcobacteraceae (Pseudoarcobacter), Pseudomonadaceae (Pseudomonas), Oxalobacteraceae (Massilia), and Flavobacteriaceae (Flavobacterium) were observed. The total coliform test indicated an intermediate level of risk of fecal contamination of the springs, except for one site. Through a questionnaire-based survey of the local population, we discovered that around 40% of participants had suffered from waterborne diseases including typhoid (~14%) and diarrhea (~11%). Our data suggests that increased surveillance of fecal contamination and heterotrophic opportunistic pathogens is needed to enhance water quality and reduce health risks for people living in mountainous regions.


Asunto(s)
Monitoreo del Ambiente , Manantiales Naturales , Humanos , Estudios Prospectivos , Abastecimiento de Agua , Calidad del Agua , Microbiología del Agua
8.
J Environ Radioact ; 266-267: 107227, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37433258

RESUMEN

Many parts of the Uttarakhand state, situated in the hilly terrain of the Himalayan region of India are facing acute water crisis due to the drying up of the perennial springs which are the only source of potable water in those regions. Tritium (3H), the radioactive isotope of hydrogen (half-life of 12.32 years) and also a part of water molecule (in the form of HTO) acts as a very useful tracer in estimating the transit time of the hydrological systems. Tritium concentrations of three springs (S-1, S-2 and S-3) were monitored consecutively for three years (2017-2019) to better constrain the transit time estimation. The tritium concentrations of the springs are found to vary between 3.66 and 4.15 TU. All the springs show gradual decrease in tritium concentration with the passage of time indicating the diminishing percentage of freshly recharged modern water component. Among various lumped parameter models, the piston-flow model (PFM), exponential mixing model (EMM), exponential piston-flow model (EPM) and partial exponential mixing model (PEM) have been employed in this study. The historical record of weighted mean concentration of tritium in precipitation available for the Uttarakhand region is taken as input function in the modelling procedure. The application of various LPMs (PFM, EMM, EPM and PEM) indicates that the transit time of the S-1 spring ranges from 1.26 to 1.46 years whereas for S-2 spring, the transit time is found to vary from 5 months to 1.1 years. The MTT of S-3 spring ranges from 5 months to 11 months. The relatively short residence time of these springs indicates the actively recharged system. The estimation of accurate transit time is thus very crucial for understanding the renewability of the spring water systems.


Asunto(s)
Manantiales Naturales , Monitoreo de Radiación , Tritio/análisis , Radioisótopos , Agua , Semivida
9.
Sci Total Environ ; 887: 163936, 2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37149179

RESUMEN

An 'oasis' signifies a refugium of safety, recovery, relaxation, fertility, and productivity in an inhospitable desert, a sweet spot in a barren landscape where life-giving water spills forth from the Earth. Remarkable mythological congruencies exist across dryland cultures worldwide where oases or 'arid-land springs' occur. In many places they also provide specialised habitats for an extraordinary array of endemic organisms. To inform their management, and maintain their integrity, it is essential to understand the hydrogeology of aquifers and springs. Gravity-fed vs artesian aquifers; actively recharged vs fossil aquifers, and sources of geothermal activity are important concepts presented here. There consequences for oases of sustainable and unsustainable groundwater extraction, and other examples of effective conservation management. Oases are archetypes for human consciousness, habitats that deserve protection and conservation, and a lingua franca for multicultural values and scientific exchange. We represent an international Fellowship of the Spring seeking to encompass and facilitate the stewardship of oases and aquifers through improved knowledge, outreach, and governance.


Asunto(s)
Agua Subterránea , Manantiales Naturales , Humanos , Becas , Ecosistema , Agua Dulce
10.
Food Chem ; 419: 136079, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37037130

RESUMEN

The sensory quality of tea is influenced by water quality, with natural spring water (NSW) gaining much attention for its natural and healthy qualities. The effects of NSW on the sensory attributes, physicochemical composition, and antioxidant capacity of Chinese tea were investigated. Tea brewed with pure water was the most resistant to oxidation and darkening. NSW with low total dissolved solids (TDS) was most suitable for brewing unfermented or mildly fermented teas, improving their sensory quality. The simulated green tea infusion system was used to investigate further the dramatic darkening of tea infusions in NSW. Exposure of infusions to air promoted the degradation, epimerization, and oxidative polymerization of catechins, and further formed theabrownins which darkened the tea infusions. These findings enabled tea consumers to choose the most suitable NSW for brewing Chinese teas and illustrated the darkening mechanism of tea infusion in high pH/TDS water.


Asunto(s)
Camellia sinensis , Catequina , Antioxidantes/química , Camellia sinensis/química , Catequina/química , Oxidación-Reducción , Té/química , Manantiales Naturales/química
11.
Environ Sci Pollut Res Int ; 30(16): 47755-47768, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36740614

RESUMEN

Freshwater macroinvertebrates have been widely used as environmental stress indicators. However, information on their response to natural thermal stress is relatively scarce, particularly in the tropics. Using the multimetric macroinvertebrate approach, the biological water quality of the warm and cold springs of the Ikogosi Warm Spring in Nigeria was evaluated, with a view to ascertaining the response of freshwater macroinvertebrates to natural thermal stress. Macroinvertebrates and water samples were collected from the warm (stressed) and cold (less-stressed) springs, as well as the confluence stream, within the renowned Ikogosi Warm Spring of Southwest Nigeria. The less-stressed cold spring had much more dissolved oxygen than the warm spring and other thermally stressed stations but less than the warm spring and other thermally stressed stations for water temperature, electrical conductivity, total dissolved solids, Ca2+, Mg2+, and water hardness. Generally, the macroinvertebrate taxonomic richness (30 species) and EPT richness (3 species) of the Ikogosi Warm Spring indicated an impaired freshwater system. Using the multimetric macroinvertebrate index (MMI), the warm spring was of poor biological water quality while the cold spring was of good biological water quality. At the confluence of both springs, the MMI declined to poor and moderate water quality. Although the thermal stress of the Ikogosi Warm Spring is natural, the government should take the necessary steps to regulate tourist activities so that the site's naturalness is preserved and the water quality is not further degraded on account of human-induced stressors such as deforestation, waste dumping, and washing activities.


Asunto(s)
Manantiales de Aguas Termales , Manantiales Naturales , Animales , Humanos , Calidad del Agua , Invertebrados/fisiología , Ríos , Monitoreo del Ambiente , Ecosistema
12.
J Contam Hydrol ; 254: 104129, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36634484

RESUMEN

Karst springs are globally important for drinking water supply but are often also exceptionally vulnerable to contamination. Such springs usually exhibit strong variation in microbial water quality in sharp response to rainfall events, thus, posing a health hazard to consumers of water supplied from these sources. The rapid detection of such changes is extremely important as well as being able to establish a link to the sources of such pollution, so that appropriate measures can be taken both in terms of immediate protection of human health and the management of karst aquifers. In this study, a fluorescence-based multi-parameter approach was trialed in order to evaluate which methods can be used to monitor rainfall-induced rapid changes in microbial water quality at karst springs, as well as determine whether such changes can be linked to sources of human effluent contamination. The results from three monitoring periods at two karst springs revealed marked responses to rainfall events for all of the microbial parameters measured. Total cell count (TCC) measurements using flow cytometry (FCM) showed very strong positive correlations with the more conventionally monitored faecal indicator bacteria (FIB) and total coliforms (TC), indicating that such a fluorescence-based and cultivation-independent technique can be very useful to indicate rapid changes in microbial water quality at karst springs. Furthermore, very strong positive correlations were also found between tryptophan-like fluorescence (TLF) measurements and concentrations of all monitored microbial parameters, again demonstrating that such a fluorescence-based approach can also be useful for detecting rapid changes in concentrations of traditional faecal indicators. Interestingly, it was found that fluorescent whitening compounds (FWCs) signals do not necessarily follow temporal variations of microbial indicators. However, the frequency of detection of positive FWCs signals may still reveal useful information about the overall magnitude of human wastewater effluent impacts on karst aquifer systems.


Asunto(s)
Agua Subterránea , Manantiales Naturales , Humanos , Monitoreo del Ambiente/métodos , Fluorescencia , Calidad del Agua , Abastecimiento de Agua
13.
Sci Total Environ ; 857(Pt 1): 159202, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36208750

RESUMEN

This study investigates the occurrence, transport, and risks associated to antibiotic residues, antibiotic resistance genes (ARGs) and antibiotic resistant Escherichia coli (AR-E. coli) in eleven natural springs in an agroecosystem environment with intense livestock production, where groundwater nitrate concentration usually sets above 50 mg L-1. Out of 23 multiple-class antibiotics monitored, tetracycline and sulfonamide residues were the most ubiquitous, and they were detected at concentrations ranging from ng L-1 to µg L-1. Five ARGs were monitored, conferring resistance to the antibiotic classes of major use in livestock production. Thus, genes conferring resistance to sulfonamides (sul1 and sul2) and tetracyclines (tetW) as well as a gene proxy for anthropogenic pollution (intI1) were present in most springs. sul1 was the most abundant, with absolute concentrations ranging from 4 × 102 to 5.6 × 106 gene copies L-1 water. AR-E. coli showing resistance to sulfonamides and tetracyclines was also detected, with a prevalence up to approximately 40 % in some sites but with poor correlations with the concentration of antibiotic residues and ARGs. The occurrence of antibiotics, ARGs and AR-E. coli was characterized by large seasonal variations which were mostly associated to both hydrological factors and reactive transport processes. Finally, a risk assessment approach pointed out towards low risk for both the groundwater environment and human health, when spring water is used for direct human consumption, associated with the occurrence of antibiotics, ARGs and AR-E. coli. However, long-term effects cannot be neglected, and proper actions must be taken to preserve groundwater quality.


Asunto(s)
Antibacterianos , Manantiales Naturales , Humanos , Antibacterianos/farmacología , Antibacterianos/análisis , Escherichia coli/genética , Genes Bacterianos , Farmacorresistencia Microbiana/genética , Tetraciclinas/análisis , Sulfonamidas , Agua , China
14.
São Paulo; s.n; 2023. 83 p.
Tesis en Portugués | LILACS | ID: biblio-1517381

RESUMEN

O combate às mudanças climáticas requer ações coletivas e através de uma nova governança que integre a sustentabilidade e gere valor compartilhado no longo prazo. Considerando o cenário do saneamento e o potencial de atração de investimentos existe uma relação simbiótica entre saneamento e desenvolvimento econômico. O ESG pode ser utilizado como ferramenta de gestão de riscos e como diretriz de comunicação às partes interessadas por organizações. Por meio de pesquisa exploratória de caráter aplicado, esse estudo desenvolveu critérios para avaliação do engajamento das companhias estaduais de saneamento com relação ao ESG. Os resultados indicam diferentes status de engajamento, diferentes metodologias e grandes oportunidades de melhoria no setor. A maioria das companhias estaduais não reporta seus dados não financeiros de forma sistemática e transparente. Os critérios apresentados podem ser utilizados por agências ambientais, fiscalizadoras e para tomada de decisão por diferentes instituições.


Climate change combating demands collective actions through a new governance which integrates sustainability and generates shared value in the long term. Considering sanitation scenario and the potential of investments attraction, there is an symbiotic relation between sanitation and economic development. The ESG criteria can be used as a tool for risk management and as a communication guidance for stakeholders. This study was developed through exploratory applied research and has proposed criteria to assess engagement of state sanitation companies regarding ESG (environmental, social and governance) standards. Results indicated different engagement status, different methodologies being applied and huge improvement opportunities in the sanitation sector. Most of the companies does not report non finance data in a systematic and transparent way. Criteria presented in this work may be used by environmental and enforcement agencies and for decision making at different institutions.


Asunto(s)
Cambio Climático , Empresas de Alcantarillado , Saneamiento Básico , Indicadores de Desarrollo Sostenible , Manantiales Naturales , Administración Financiera
15.
Sensors (Basel) ; 22(19)2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-36236229

RESUMEN

Groundwater resource assessment and forecasting in mountain areas requires the monitoring of two conditions, local meteorological conditions, and springs' groundwater parameters. The reliability of the monitoring data and conditions are linked to the technical instrumentation, multiparametric probes, and sensors. This paper presents a set of attractive tools and sensors for springs' groundwater resource monitoring and assessment in mountain basins. Data from the combination of weather station sensors with spring flow-rate instruments, installed in the alpine Mascognaz basin, can guarantee an entire understanding of how one set of parameters can affect other results, defining consequential cause-and-effect relationships. Since a large part of the Alpine groundwater bodies are exploited for drinking purposes, understanding the evolution of their rechange processes requires making the right economic and instrumental investments aimed at using them according to forecast predictions and sustainable development goals.


Asunto(s)
Agua Subterránea , Manantiales Naturales , Comprensión , Monitoreo del Ambiente , Reproducibilidad de los Resultados , Tiempo (Meteorología)
16.
Zootaxa ; 5169(5): 472-480, 2022 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-36095430

RESUMEN

A new monotypic genus of freshwater snail from late Holocene spring deposits in Viesca, Coahuila (Mexico), is described based on shell morphology. Spinopyrgus luismaedai n. gen. et n. sp. has two to three carinate shells with long and wide shovel-shaped spines, strong axial ridges and a pointed protoconch. All sculptural ornamentations on the teleoconch are part of the calcareous shell material and not projections of the periostracum. This combination of shell features and their almost marine-like appearance is unknown among North American recent and fossil freshwater snails. Because of its shell characteristics, we placed the new genus tentatively in the Cochliopidae. The springs of Viesca dried up in the second half of the 20th century so that any living occurrence of this species in neighboring areas is unlikely, rendering the new genus and species possibly extinct.


Asunto(s)
Manantiales Naturales , Caracoles , Animales , Fósiles , Agua Dulce , México
17.
Sci Rep ; 12(1): 7679, 2022 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-35538207

RESUMEN

As a traditional water source, springs are vital for Himalayan communities and it is essential to consciously focus on springs conservation. We report oxygen isotopes (δ18O) of spring water before, within, and after the tectonically active zones of the Alaknanda Valley, Uttarakhand. Higher variation of δ18O in the spring waters is found in highly tectonically disturbed zone i.e., Zone-2 with δ18O range - 4.9‰ to - 9.0‰ compared to tectonically less disturbed zones: Zone-1 and Zone-3 with δ18O value range - 7.9‰ to - 9.9‰ and - 7.4 to - 10.2‰ respectively. We hypothesize that the highly active thrust zones (Zone-2) with increased permeability compared to other Zones, manifested as greater spring density, results in higher water recharge in Zone-2. Very high to high spring density stretches are dominant in Zone-2 compared to Zone-1 and Zone-3. Stretches in Zone-2 with high spring density formed due to its highly tectonically active nature leads to the higher isotopic variation in Zone-2. The study also identifies the geosystem services provided by thrust zones as water resources to the local people and need of conservation modalities to manage the spring water resources in the thrust zones.


Asunto(s)
Monitoreo del Ambiente , Manantiales Naturales , Ambiente , Monitoreo del Ambiente/métodos , Humanos , Isótopos de Oxígeno/análisis , Agua
18.
PLoS One ; 17(5): e0264501, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35511881

RESUMEN

In many respects, freshwater springs can be considered as unique ecosystems on the fringe of aquatic habitats. This integrates their uniqueness in terms of stability of environmental metrics. The main objective of our study was to evaluate how environmental variables may shape invertebrate diversity and community composition in different freshwater spring types and habitats within. In order to do so, we sampled invertebrates from 49 springs in Iceland, where we included both limnocrene and rheocrene springs. At each site, samples were taken from the benthic substrate of the spring ("surface") and the upwelling groundwater at the spring source ("source"). To collect invertebrates from the spring sources we used a modified method of "electrobugging" and Surber sampler for collecting invertebrates from the surface. In total, 54 invertebrate taxa were identified, mostly Chironomidae (Diptera). Chironomid larvae also dominated in terms of abundance (67%), followed by Ostracoda (12%) and Copepoda (9%). The species composition in the surface samples differed considerably between rheocrene and limnocrene springs and was characterised by several indicator species. Alpha diversity was greater at the surface of springs than at the source, but the beta diversity was higher at the source. Diversity, as summarized by taxa richness and Shannon diversity, was negatively correlated with temperature at the surface. At the source, on the other hand, Shannon diversity increased with temperature. The community assembly in springs appears to be greatly affected by water temperature, with the source community of hot springs being more niche-assembled (i.e., affected by mechanisms of tolerance and adaptation) than the source community of cold springs, which is more dispersal-assembled (i.e., by mechanisms of drift and colonization).


Asunto(s)
Manantiales de Aguas Termales , Manantiales Naturales , Animales , Biodiversidad , Ecosistema , Agua Dulce , Invertebrados
19.
Sci Total Environ ; 838(Pt 2): 156041, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-35597350

RESUMEN

Over the last several decades, rising nitrate concentrations in springs discharging from north Florida's karstic Upper Floridan Aquifer have coincided with proliferation of algae in Florida spring runs and subsequent ecosystem degradation. As agriculture and development are primary contributors to groundwater nitrate and are predicted to continue expanding, understanding unique contributions and transmission pathways of nitrate pollution is vital to restoring impaired spring ecosystems. In this study, we use statistics and signal processing to analyze continuous nitrate timeseries data collected over five years at four north Florida springs. We quantified a significant, low-frequency annual signal in nitrate concentrations superimposed on increasing nitrate trends. We show nitrate concentrations at springs increase during the rainy season, potentially in response to recharge and seasonal fertilizer application. Thus, we suggest seasonal fluctuations observed in nitrate concentrations are caused by increased recharge of nutrient-rich soil waters through fractures that deliver water on relatively short timescales to conduits during the rainy season. We further speculate the steady, monotonically increasing concentration is maintained by accumulation of Nitrogen as slow flow through matrix porosity through the remainder of the year. Seasonal nitrate concentrations resulting from flow through karst aquifers may thus be poorly simulated using equivalent porous media models that are increasingly being used for nutrient management, because they do not capture heterogenous flow and transport dynamics.


Asunto(s)
Agua Subterránea , Manantiales Naturales , Contaminantes Químicos del Agua , Ecosistema , Monitoreo del Ambiente/métodos , Nitratos/análisis , Contaminantes Químicos del Agua/análisis
20.
PLoS One ; 17(5): e0268252, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35522687

RESUMEN

Turbidite successions can behave either as aquitards or aquifers depending on their lithological and hydraulic features. In particular, post-depositional processes can increase rock permeability due to fracture development in the competent layers. Thus, at a local scale, turbidite systems warrant further detailed investigations, aimed at reconstructing reliable hydrogeological models. The objective of this work was to investigate from the hydrogeological perspective a turbiditic aquifer located in southern Italy, where several perennial and seasonal springs were detected. Considering the complex hydrodynamics of these systems at the catchment scale, to reach an optimal characterization, a multidisciplinary approach was adopted. The conceptual framework employed microbial communities as groundwater tracers, together with the physicochemical features and isotopic signature of springs and streams from water samples. Meanwhile, geophysical investigations coupled with the geological survey provided the contextualization of the hydrogeological data into the detailed geological reconstruction of the study area. This modus operandi allowed us to typify several differences among the samples, allowing identification of sources and paths of surface water and groundwater, along with diffuse groundwater outflow along streams. As a final result, a hydrogeological conceptual model was reconstructed, underlining how at a very local scale the lithologic, hydraulic, and geomorphological heterogeneity of the studied relief can lead to an improved hydrogeological conceptual model compared to that of other turbidite systems. These results open new questions about the hydrogeological behavior of turbiditic aquifers, which could be pivotal in future research. In fact, these systems could support relevant ecosystems and anthropic activities, especially where climate change will force the research of new (and probably less hydrogeologically efficient) water sources.


Asunto(s)
Agua Subterránea , Manantiales Naturales , Ecosistema , Monitoreo del Ambiente , Agua Subterránea/química , Agua
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