scholarly journals Tidally Forced Saltwater Intrusions might Impact the Quality of Drinking Water, the Valdivia River (40° S), Chile Estuary Case

Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2387
Author(s):  
José Garcés-Vargas ◽  
Wolfgang Schneider ◽  
Andre Pinochet ◽  
Andrea Piñones ◽  
Francisco Olguin ◽  
...  
Keyword(s):  
Drinking Water ◽  
Saline Water ◽  
River Estuary ◽  
Fractional Power ◽  
Central Chile ◽  
Climate Conditions ◽  
South Central ◽  
Four Seasons ◽  
The Pacific

The Valdivia River estuary (VRE) located in south-central Chile is known as one of the largest estuarine ecosystems on the Pacific coast. This research aims to determine the intra-tidal and sub-tidal variability of saline intrusions into the VRE between November 2017 and March 2019 derived from salinity sensors located along the VRE. Complementary hydrographic measurements were conducted during flood and ebb conditions of the spring and neap tides for each of the four seasons of the year along the central axis of the VRE. The results of the salinity time series showed that saline intrusions (values greater than 0.5 Practical Salinity Units) occurred ~20 km from the estuary mouth, when the total flow of the Cruces and Calle-Calle rivers (main tributaries of the estuary) was low, around 280–300 m3 s−1. During the same period, the best co-variability was observed between the saline intrusions and the mixed-semidiurnal tide and the fortnightly and monthly periods of the tide. Regression analyses indicated that salinity intrusion length (L) is best correlated to discharge (D) with a fractional power model L α D−1/2.64 (R2 = 0.88). The decreasing discharge trend, found between 2008–2019, implies that saline water intrusions would negatively impact the Valdivia’s main drinking water intake during the low rainfall season under future climate conditions.

scholarly journals Two new species of Microcotyle (Monogenea: Microcotylidae) on intertidal fish from the south Pacific coast

2020 ◽  
Vol 54 (3) ◽  
pp. 283
Author(s):  
Gabriela Muñoz ◽  
Mario George-Nascimento
Keyword(s):  
New Species ◽  
Pacific Coast ◽  
Valid Species ◽  
Base Pairs ◽  
Central Chile ◽  
South Central ◽  
The Pacific ◽  
The Family ◽  
Two New Species ◽  
Intertidal Fish

Microcotyle is one of the most diverse and controversial genera within the family Microcotylidae. To date, 131 species have been described in Microcotyle; however, more than half have been transferred to other genera, and several others have poor descriptions. Therefore, less than half of all Microcotyle species may be considered valid. In Chile, two species have been recognized, and unidentified Microcotyle have been found on several littoral fish, but there has been no effort to properly identify them. In this study, two new species of Microcotyle are taxonomically described from intertidal fish of the central (33°S) and south-central (36°S) regions of Chile. In this study, Microcotyle sprostonae n. sp. (collected mainly from Scartichthys viridis in central Chile) and M. chilensis n. sp. (collected mainly from Calliclinus geniguttatus in south-central Chile) were identified based on morphological and molecular analyses (ITS2 and 18S genes). Both species of Microcotyle principally differed from one another and from other valid species in the number of testes and clamps. The two new species also differed from one another by one base pair in the ITS2 and 18S genes and differed from other species of Microcotyle by several base pairs of both genes. Intertidal fish are mostly endemic to the Pacific coast of South America, and they have a limited geographical distribution that does not overlap with the type hosts of other Microcotyle species. Therefore, the two new species described here are distinguished from other congeneric species by morphological, genetic, and biological characteristics.

The effect on egg shell quality of supplementing saline drinking water with sodium or ammonium bicarbonate

1990 ◽  
Vol 41 (6) ◽  
pp. 1187 ◽  
Author(s):  
I Yoselewitz ◽  
D Zhang ◽  
D Balnave
Keyword(s):  
Drinking Water ◽  
Egg Production ◽  
Saline Water ◽  
Ammonium Bicarbonate ◽  
Fluid Composition ◽  
Shell Quality ◽  
Egg Shell ◽  
The Town ◽  
Reduced Water

Supplementing the town water supply of laying hens with 600 mg sodium chloride (NaCl)/L significantly decreased egg shell quality and significantly increased the incidence of egg shell defects without affecting egg production and egg weight or food and water intakes. A smaller, but still significant, increase in egg shell defects was also observed with sodium bicarbonate (NHCO3) supplementation of town water. Ammonium bicarbonate (NH4HCO3) supplementation of town water had no significant effect on egg shell defects and, when added to drinking water containing NaCl, significantly reduced the incidence of shell defects. A smaller beneficial effect was observed when NHCO3was added to saline water. Ammonium bicarbonate, when added to saline drinking water at concentrations of 250 and 450 mg/L, reduced water intake, an effect not observed when these same supplements were added to town water. This suggests that the presence of NaCl in the water may affect kidney function so that the use of NH4HCO3may have limited value, especially at higher water salinities. Shell gland fluid composition was influenced less by treatment than by whether or not hens were laying eggs with defective shells.

Population Biology of the Intertidal Snail Chilina ovalis Sowerby (Pulmonata) in the Queule River Estuary, South-Central Chile

Estuaries ◽  
2001 ◽  
Vol 24 (1) ◽  
pp. 69 ◽  
Author(s):  
Pedro Quijón ◽  
Heraldo Contreras ◽  
Eduardo Jaramillo ◽  
Pedro Quijon
Keyword(s):  
Population Biology ◽  
River Estuary ◽  
Central Chile ◽  
South Central ◽  
Intertidal Snail

scholarly journals The impact of rainfall on drinking water quality in Antananarivo, Madagascar

2019 ◽  
Author(s):  
Alexandra Bastaraud ◽  
Emeline Perthame ◽  
Jean-Marius Rakotondramanga ◽  
Jackson Mahazosaotra ◽  
Noro Ravaonindrina ◽  
...  
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Low Income ◽  
Temporal Dynamics ◽  
Drinking Water Quality ◽  
Population Pressure ◽  
Direct Effects ◽  
Climate Conditions ◽  
The Impact

AbstractLow-income cities that are subject to high population pressure and vulnerable to climate events often have a low capacity to continuously deliver safe drinking water. Here we report the findings of a 32-year investigation of the temporal dynamics of indicators of drinking water quality in the city of Antananarivo, where we assess the long-term evolution of supplied water quality and characterize the interactions between climate conditions and the full-scale supply system. A total of 25,467 water samples were collected every week at different points in the supplied drinking water system. Samples were analyzed for total coliforms (TC), Escherichia coli (EC), intestinal Enterococci (IE), and spores of Clostridia (SSRC). Nine-hundred-eighty-one samples that were identified as positive for one or more indicators were unevenly distributed across the series. The breakpoint method identified four periods when the time series displayed changes in the level and profile of contamination (i) and the monthly pattern of contamination (ii), with more direct effects of rainfall on the quality of supplied drinking water. The modeling showed significantly different lags among indicators of bacteria occurrence after cumulative rainfall, which range from 4 to 8 weeks. Among the effects of low-income urbanization, a rapid demographic transition and urban watershed degradation are progressively affecting the quality of supplied water and resulting in the more direct effects of rainfall events.

scholarly journals Some issues of water quality used for drinking and household consumption in Khujirt sum of Uvurkhangai province

2018 ◽  
Vol 25 (03) ◽  
pp. 174-183
Author(s):  
Tsetsegmaa Z ◽  
Gantulga N ◽  
Oyunchimeg T
Keyword(s):  
Drinking Water ◽  
Maximum Rate ◽  
Potable Water ◽  
Environment And Health ◽  
Chemical Indicators ◽  
Four Seasons ◽  
Water Ph ◽  
Purification Equipment ◽  
Very High

In 2015-2018 quality of potable water from 10 wells of Khujirt soum center, Uvurkhangai aimag was tested 11 times against 9 chemical indicators during four seasons. Content of nitrate within water from wells of school dormitory, new residential apartments was found to 2,9% excess from allowed maximum limit, water PH in wells of “Elma Khujirt” LLC, “Anand Khujirt” LLC and Health center had exceeded by 17,5% from allowed maximum, iron content exceeded allowed maximum rate of 0.37-0.39 in “Elma Khujirt” LLC, “Anand Khujirt” LLC wells by 3.85% which failed to comply with MNS 900:2010, standard on safety of environment and health protection, requirement for hygiene of drinking water. Bacteria content in Khaluun us river which flows through Khujirt soum center is found 0.2-2.8 times more than provided in the standards. There is very high risk for elders, people with chronic diseases and children of young age with poor immunity to get sick unless to take sanitation and disinfection measures of drinking water, install water purification equipment on residential apartment pipes. Өвөрхангай аймгийн Хужирт сумын унд ахуйн хэрэглээнд ашиглагддаг усны чанарын зарим асуудал Хураангуй: Өвөрхангай аймгийн Хужирт сум нь 171.782 га нутагтай. Түүний 0.08% буюу 143.24 га талбайг усан сан бүхий газар эзэлдэг. 2017 оны усны тооллогоор нийт 14 гол, халуун, хүйтэн 2 рашаан, 103 булаг шанд, 8 нуур, байнгын үйл ажиллагаатай 38 гүн өрмийн худаг тоологдсон. Сумын нийт хүн ам 6751 бөгөөд сумын төвд 1018 өрхийн 2918 хүн оршин суудаг. Сумын төвд цэвэр усны 14, халуун рашааны 4 гүн өрмийн худаг байна. Халуун рашаан, эмчилгээний шаврыг түшиглэн 6 амралт сувиллын газар, цэвэр усны 1 үйлдвэр байнгын үйл ажиллагаа явуулж байна. Жил ирэх тусам хүн амын төвлөрөлт, амралт сувиллын газарт ирж сувилуулах сувилуулагчуудын тоо нэмэгдсэнээр рашаан, шаврын хэрэглээ, цэвэр усны үйлдвэрт ашиглагдах усны хэмжээ нэмэгдэж байна. Тэдгээрээс гарч буй бохир усыг цэвэрлэх цэвэрлэх байгууламж нь стандартын түвшинд цэвэрлэж чадахгүй бохир усыг хөрсөнд шууд хаяж, сумын төв дэх Халуун усны голд нийлэн урсан Орхон гол цутгах, айл өрх, аж ахуйн нэгж, байгууллагууд нь стандартын бие засах газар байхгүй, сумын хэмжээнд нэгдсэн цэвэрлэх байгууламж байхгүйгээс гадаргын болон гүний усны чанарт сөргөөр нөлөөлж буй нь сүүлийн 6-7 жилүүдэд мэдэгдэхүйц ажиглагдаж байна. Ийм учраас Өвөрхангай аймгийн Хужирт сумын төв дэх гүний худгийн болон гадаргын усны чанарыг усны голлох үзүүлэлт болох хими, физик, нянгийн үзүүлэлтээр тодорхойлж, бохирдолтыг бууруулах, урьдчилан сэргийлэх боломжтой арга хэмжээг зөвлөмжлөхийн тулд энэхүү сэдвийг сонгосон болно. Tүлхүүр үг: Усны бохирдол, газрын доорхи ус, рашаан, усны чанар

Adverse responses in egg shell quality in late-lay resulting from short-term use of saline drinking water in early- or mid-lay

1998 ◽  
Vol 49 (7) ◽  
pp. 1161 ◽  
Author(s):  
D. Balnave ◽  
D. Zhang
Keyword(s):  
Drinking Water ◽  
Sodium Chloride ◽  
Adverse Effects ◽  
Water Supply ◽  
Saline Water ◽  
Short Term ◽  
Shell Quality ◽  
Egg Shell

Three experiments were carried out to determine the long-term responses in egg shell quality when hens were given saline drinking water for only a few weeks either at the start of lay or in mid-lay. Shell quality of eggs from hens given town water containing an additional 2 g sodium chloride (NaCl)/L as drinking water for periods of 5 or 6 weeks prior to 30 weeks of age or between 48 and 53 weeks of age was significantly poorer at the end of lay than shell quality of eggs from hens given town water throughout lay. Apart from these short periods of saline water supply the NaCl-treated hens received town water throughout lay. Shell defects were increased significantly after 55 weeks of age even when no apparent detrimental effects of saline drinking water on shell quality were observed during the period of saline water intake or when the incidence of shell defects returned to normal after the replacement of saline water with town water. The results indicate that the adverse effects of saline drinking water on egg shell quality is of long-term significance, being especially noticeable towards the end of lay.

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