scholarly journals Temporal Variation of Coastal Groundwater Quality in East Coast of Terengganu, Malaysia

2018 ◽  
Vol 7 (3.14) ◽  
pp. 151
Author(s):  
Norsyuhada Hairoma ◽  
Muhammad Barzani Gasim ◽  
Mohd Ekhwan Toriman ◽  
Hafizan Juahir ◽  
Azman Azid ◽  
...  

Coastal groundwater is extremely vulnerable to saltwater contamination. This study was conducted to investigate the potential contamination of saltwater into coastal groundwater temporally. Data was obtained from PT000017 monitoring well from 2006 to 2012. Nine parameters of water quality were involved for data analyses. Two main diagrams used for data analyses are piper diagram and hydrochemical facies evolution diagram (HFE-D). All parameters were plotted to produce a piper diagram that determine the water type between different seasons. During wet season, groundwater samples are located in domain III that represent mixed Ca-Na-HCO3 water type; 2007 groundwater sample was located in domain I, represent Ca-HCO3 water type and during 2008 groundwater sample was located in domain II, represent Na-Cl water type. During dry season, groundwater samples are located in domain II that represent mixed Ca-Na-HCO3 water type meanwhile, 2009 and 2011 groundwater samples are located in domain I, represent Ca-HCO3 water type. Subsequently, HFE-D diagram was produced to determine the evolution process of salinization or freshening of coastal groundwater. In this study, all of groundwater samples were in freshening stage except during dry season 2007 groundwater sample was in the phase of saltwater intrusion.

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1524
Author(s):  
Ramita Bajracharya ◽  
Takashi Nakamura ◽  
Subesh Ghimire ◽  
Bijay Man Shakya ◽  
Naresh Kazi Tamrakar

Interconnection between river water and groundwater plays an important role in maintaining water quantity and quality in hydrological systems. Furthermore, the exact interconnection is often difficult to observe and measure. This study attempts to explain river and shallow groundwater interconnection in urbanized areas of the Kathmandu Valley, Nepal. Isotopic (δD and δ18O) and chemical analyses were performed on river and groundwater samples, and the results were analyzed using statistical methods to identify areas of interconnection between river water and groundwater. Higher concentrations and positive strong correlations of Na+ with K+, NH4+-N, Cl−, HCO3−, and PO4−-P, and a change of water type from Ca-HCO3 during the wet season to Na-K-HCO3 during the dry season indicate higher contamination in river water during the dry season. Hierarchical cluster analysis was used in grouping water samples into clusters on the basis of isotopic and chemical (Na+ and Cl−) composition. Grouping of river and groundwater samples in one–one clusters from wet and dry seasons shows the presence of interconnection, indicating the contribution of river water in recharging shallow groundwater. These results imply that shallow groundwater found near rivers is chemically contaminated by polluted river water through bank infiltration, in both wet and dry seasons.


2021 ◽  
Vol 13 (1) ◽  
pp. 21-42
Author(s):  
Berihu Abadi Berhe ◽  
Fethangest Woldemariyam Tesema ◽  
Gebreslassie Mebrahtu

The study area, Kombolcha town, forms an important industrial town situated in the Eastern Amhara region, Ethiopia. The geology of the area is mainly composed of basalts, rhyolitic ignimbrites, and Quaternary sediments. Hydrogeochemistry and the source of ions in the groundwater of the study area are poorly understood. Therefore, the current study aims to assess the factors and the different hydrochemical processes significantly controlling groundwater quality, source, and chemistry. For this purpose, a total of eighteen groundwater samples were collected using 250 ml sampling bottles at selected points in the dry season (May 2017) and wet season (November 2017). Gibbs diagram, correlation analysis, scatter plots of ionic molar ratio relations, saturation index values (estimated using PHREEQC Interactive 2.8) were used to decipher the hydrogeochemical process. Gibbs diagram shows that the rock-water interaction process is the predominant, Na+/Cl- and Ca2+/Mg2+ molar ratio value of all groundwater samples in both seasons reveals that the groundwater chemistry of the area is controlled by silicate minerals weathering. The strong correlation of Ca2+ with Mg2+ in the dry season, and Ca2+ with HCO3- and Na+ with HCO3- in the wet season could also be an indication of silicate weathering and ion exchange processes. The impact of anthropogenic practices on groundwater chemistry is also seen from the strong correlation of Ca2+ with Cl-, NO3-, PO43- and F-, NO2- with K+, Mg2+, and PO43- , PO43- with F- , and NO3- with Na+, Cl-, HCO3- . The negative values of chloro-alkaline indices in both seasons indicate base-exchange reaction where an indirect exchange of Ca2+ and Mg2+ of the water with Na+ and K+ of the host rock occurs. Saturation indices results for the wet season show that the groundwater is under-saturated with respect to calcite, aragonite, dolomite, gypsum, and anhydrite. In the dry season, however, some of the waters are oversaturated with respect to calcite and aragonite. To sum up, the groundwater quality of the study area is controlled by geological processes and anthropogenic effects.


2019 ◽  
pp. 1336-1349
Author(s):  
Osamah N. Al-Sheikh ◽  
Ayser M. AL-Shamma'a

The quality of groundwater is just as important as its quantity. The kinds and concentration of salts in groundwater depend on the environment, movement, and the source of the groundwater. During the field work, 20 samples have been collected from water wells from Al-Salman basin for two seasons represent wet and dry seasons in November 2017 and April 2018. After water well samples have been analyzed the Electrical conductivity values range from (2260 to 5500) μS/cm for dry season and range from (2540 to 5630) μS/cm for wet season, the Total dissolved solids values range from (1289 to 3582) ppm for dry season and range from (1710 to 3960) ppm for wet season, and pH values range from (7.11 to 7.3) for dry and wet seasons. The Hydrochemical classification which applied using Piper's Diagram revealed there are three type of water (sulphate type Ca+2 – Mg+2 – Cl- – SO4, sulphate type Ca+2 – Mg+2 – Cl- - SO4, NaCl), and two water type by applying Chadha's diagram (sulphate type Ca+2 – Mg+2 – Cl- - SO4, Na+- Cl-), the variation of water type in the study area due to influence of Rus Formation which consists of anhydrite, and structure roles where made precipitation concentrate in Al-Salman depressions and streams flow faults that ended with playa.


2021 ◽  
Vol 54 (2A) ◽  
pp. 103-111
Author(s):  
Qusai Y. Al-Kubaisi

The main aim of the research is to study the groundwater quality in Al-Khasfa area within Haditha district, western Iraq. To assess the groundwater, eighteen groundwater samples in the study area were collected and analyzed for major cations and anions. Results indicated that groundwater samples in the study area are between neutral and light alkaline, slightly brackish, and highly mineralized. The hydrochemical formula of the groundwater samples indicates the Ca-SO4 type dominance, except wells number 16 and 17 were of Ca-Cl water type. According to Piper diagram, the type of water is Earth-Alkaline waters. All groundwater samples are unsuitable for human drinking, industrial, and building uses, but it is suitable for livestock. For irrigation purposes, it is characterized by no Mg-harmful, good with SAR, Na%, RSC, and PI but unsuitable for salinity hazard due to very high salinity. The Water Quality Index for Euphrates aquifer in the study area in both periods are poor water for human drinking, except W-1 in dry period indicate very poor water and W-6, W-7, W-8, W-13, W-14, W-15, W-16 in wet period indicate good water.


BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Xue Zhu ◽  
Jiyue Qin ◽  
Chongyang Tan ◽  
Kang Ning

Abstract Background Most studies investigating human gut microbiome dynamics are conducted on humans living in an urban setting. However, few studies have researched the gut microbiome of the populations living traditional lifestyles. These understudied populations are arguably better subjects in answering human-gut microbiome evolution because of their lower exposure to antibiotics and higher dependence on natural resources. Hadza hunter-gatherers in Tanzania have exhibited high biodiversity and seasonal patterns in their gut microbiome composition at the family level, where some taxa disappear in one season and reappear later. Such seasonal changes have been profiled, but the nucleotide changes remain unexplored at the genome level. Thus, it is still elusive how microbial communities change with seasonal changes at the genome level. Results In this study, we performed a strain-level single nucleotide polymorphism (SNP) analysis on 40 Hadza fecal metagenome samples spanning three seasons. With more SNP presented in the wet season, eight prevalent species have significant SNP enrichment with the increasing number of SNP calling by VarScan2, among which only three species have relatively high abundances. Eighty-three genes have the most SNP distributions between the wet season and dry season. Many of these genes are derived from Ruminococcus obeum, and mainly participated in metabolic pathways including carbon metabolism, pyruvate metabolism, and glycolysis. Conclusions Eight prevalent species have significant SNP enrichments with the increasing number of SNP, among which only Eubacterium biforme, Eubacterium hallii and Ruminococcus obeum have relatively high species abundances. Many genes in the microbiomes also presented characteristic SNP distributions between the wet season and the dry season. This implies that the seasonal changes might indirectly impact the mutation patterns for specific species and functions for the gut microbiome of the population that lives in traditional lifestyles through changing the diet in wet and dry seasons, indicating the role of these variants in these species’ adaptation to the changing environment and diets.


Diversity ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 319
Author(s):  
Cristian Pérez-Granados ◽  
Karl-L. Schuchmann

Climatic conditions represent one of the main constraints that influence avian calling behavior. Here, we monitored the daily calling activity of the Undulated Tinamou (Crypturellus undulatus) and the Chaco Chachalaca (Ortalis canicollis) during the dry and wet seasons in the Brazilian Pantanal. We aimed to assess the effects of climate predictors on the vocal activity of these focal species and evaluate whether these effects may vary among seasons. Air temperature was positively associated with the daily calling activity of both species during the dry season. However, the vocal activity of both species was unrelated to air temperature during the wet season, when higher temperatures occur. Daily rainfall was positively related to the daily calling activity of both species during the dry season, when rainfall events are scarce and seem to act as a trigger for breeding phenology of the focal species. Nonetheless, air temperature was negatively associated with the daily calling activity of the Undulated Tinamou during the wet season, when rainfall was abundant. This study improves our understanding of the vocal behavior of tropical birds and their relationships with climate, but further research is needed to elucidate the mechanisms behind the associations found in our study.


Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 320
Author(s):  
Qianyao Si ◽  
Mary G. Lusk ◽  
Patrick W. Inglett

Stormwater infiltration basins (SIBs) are vegetated depressions that collect stormwater and allow it to infiltrate to underlying groundwater. Their pollutant removal efficiency is affected by the properties of the soils in which they are constructed. We assessed the soil nitrogen (N) cycle processes that produce and remove inorganic N in two urban SIBs, with the goal of further understanding the mechanisms that control N removal efficiency. We measured net N mineralization, nitrification, and potential denitrification in wet and dry seasons along a sedimentation gradient in two SIBs in the subtropical Tampa, Florida urban area. Net N mineralization was higher in the wet season than in the dry season; however, nitrification was higher in the dry season, providing a pool of highly mobile nitrate that would be susceptible to leaching during periodic dry season storms or with the onset of the following wet season. Denitrification decreased along the sediment gradient from the runoff inlet zone (up to 5.2 μg N/g h) to the outermost zone (up to 3.5 μg N/g h), providing significant spatial variation in inorganic N removal for the SIBs. Sediment accumulating around the inflow areas likely provided a carbon source, as well as maintained stable anaerobic conditions, which would enhance N removal.


2012 ◽  
Vol 63 (9) ◽  
pp. 788 ◽  
Author(s):  
N. E. Pettit ◽  
T. D. Jardine ◽  
S. K. Hamilton ◽  
V. Sinnamon ◽  
D. Valdez ◽  
...  

The present study indicates the critical role of hydrologic connectivity in floodplain waterholes in the wet–dry tropics of northern Australia. These waterbodies provide dry-season refugia for plants and animals, are a hotspot of productivity, and are a critical part in the subsistence economy of many remote Aboriginal communities. We examined seasonal changes in water quality and aquatic plant cover of floodplain waterholes, and related changes to variation of waterhole depth and visitation by livestock. The waterholes showed declining water quality through the dry season, which was exacerbated by more frequent cattle usage as conditions became progressively drier, which also increased turbidity and nutrient concentrations. Aquatic macrophyte biomass was highest in the early dry season, and declined as the dry season progressed. Remaining macrophytes were flushed out by the first wet-season flows, although they quickly re-establish later during the wet season. Waterholes of greater depth were more resistant to the effects of cattle disturbance, and seasonal flushing of the waterholes with wet-season flooding homogenised the water quality and increased plant cover of previously disparate waterholes. Therefore, maintaining high levels of connectivity between the river and its floodplain is vital for the persistence of these waterholes.


1992 ◽  
Vol 43 (2) ◽  
pp. 241 ◽  
Author(s):  
JJ Mott ◽  
MM Ludlow ◽  
JH Richards ◽  
AD Parsons

The close correlation between grazing-induced mortality and major climatic patterns in Australian savannas, led us to the hypothesis that moisture conditions during the dry, non-growing season could affect sensitivity to grazing in the subsequent growing season. Using three widespread savanna species (Themeda triandra, Heteropogon contortus and Panicum maximum), this hypothesis was tested experimentally and the mechanisms controlling this response examined and quantified. In T. triandra drought during the dry season led to major mortality in defoliated plants in the next growing season. This mortality was caused by a synchrony of tillering at the commencement of the wet season, leaving few buds for replacement once parent tillers were killed by defoliation. T. triandra was also the most sensitive species to defoliation. This sensitivity was due to the poor ability of the plant to maintain positive carbon gain after defoliation. Several factors contributed to this poor ability, including: low total photosynthetic rate, low specific leaf area, and a large proportion of sheath material with poor photosynthetic capacity remaining after cutting. Both H. contortus and P. maximum growing under irrigated and fertilized conditions did not display any effects of previous moisture treatments when defoliated during the next wet season and were much less sensitive to defoliation than T. triandra.


1983 ◽  
Vol 10 (3) ◽  
pp. 639 ◽  
Author(s):  
GJW Webb ◽  
SC Manolis ◽  
GC .Sack

A 52.5-km section of the Adelaide River, N.T. (12�13'S., 131�13'E.). was spotlight-surveyed 20 times between June 1979 and September 1981. C, johnstoni (15.3 � 9.2 sighted per survey) were less abundant than C. porosus (137.6 � 36.5 sighted per survey), and were mainly in the upstream 20 km of the survey route (96% of C. johnstoni sightings); here considered a zone of syntopy within the survey route. C. johnstoni congregate in the main stream during the dry season and disperse from it during the wet season, which parallels similar seasonal movements to and from dry-season refuges in non-tidal areas lacking C. porosus. As the dry season progresses, C. johnstoni are located further and further upstream, and this movement (or loss ofanimals) appears unrelated to changes in salinity. Numbers of C.johnstoni within the zone of syntopy are negatively correlated with numbers of C. porosus (r*2 = 0.50, P=0.005). and competitive exclusion may be occurring. Independent of seasonal factors, numbers of C. johnstoni within the zone of syntopy declined with consecutive month (1979-81: r*2=0.47, P= O.004), whereas numbers ofthe more recently protected C, porosus increased (r2 = 0.48, P= 0,006). The location of the syntopic zone was unchanged.


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