Determination of the Physico-Chemical Quality of the Waters of the Mamouwol River in the Urban Commune of Mamou, Republic of Guinea

Water is one of the most important elements on which our daily lives depend,because of its many uses in various fields.To ensure that people have the right of access to water,the authorities must provide them with treated water that complies with the regulations and standards in force,particularly from a physico-chemical point of view,for all possible uses to avoid any health problems for consumers.The aim of this research is to study the water in the Mamouwol River by measuring physico-chemical parameters:(1)pH,it varies from 5.2“Mam3”to 7.8“Mam4”in August 2021 then from 5.5“Mam3”to 7.7“Mam4”in March 2022,i.e.an average of 6.9 for all sampling points;(2)Turbidity varies from 0.3 NTU“Mam1”to 26.3 NTU“Mam4”in August 2021,then from 0.3 NTU“Mam1”to 30.6 NTU“Mam4”in March 2022,i.e.an average of 9.0 NTU for all sampling points;(3)Suspended matter,varying from 0.6 mg/L“Mam1”to 17.6 mg/L“Mam4”in August 2021,then from 0.6 mg/L“Mam1”to 30.0 mg/L“Mam4”in March 2022,i.e.an average of 8.8 mg/L for all the sampling points“Mam1”,“Mam2”,“Mam3”and“Mam4”;(4)Dissolved oxygen,varying from 2.07 mg/L“Mam3”to 6.12 mg/L“Mam1”in August 2021,then from 1.05 mg/L“Mam3”to 5.05 mg/L“Mam1”in March 2022,i.e.an average of 2.77 mg/L for all sampling points;(5)Nitrates vary from 1.32 mg/L“Mam1”to 3.96 mg/L“Mam4”in August 2021,then from 1.49 mg/L“Mam1”to 5.27 mg/L“Mam3”in March 2022,i.e.an average of 5.53 mg/L for all sampling points;(6)Nitrites,varying from 0 mg/L“Mam1”and“Mam2”to 0.06 mg/L“Mam3”in August 2021,then from 0 mg/L“Mam1”and“Mam2”to 0.13 mg/L“Mam3”in March 2022,i.e.an average of 0.03 mg/L for all sampling points.The results show the presence of organic pollution.

TRANSFERABLE PHOSPHORUS IN SEDIMENTS OF THE HUANGHE RIVER ESTUARY'S ADJACENT WATERS

Based on a new idea for research on cycling of marine biogenic elements, this study showed that only the leachable form phosphorus in natural grain sizes marine sediments constitutes the transferable phosphorous in the sediments. The transferable phosphorus content in the natural grain sizes surface sediments in the Huanghe River estuary adjacent waters ranges from 58.5-69.8 μg/g, accounting for only 9.1%-11.0% of the total phosphorus content, whereas the leachable form (“transferable") phosphorus content in the sediment after it was totally ground into powder was found to be 454.8-529.2 μg/g, accounting for 73.4%-89.1% of the total phosphorus. Analysis of the correlation between the biomass of benthos and the leachable form (“transferable") phosphorus showed that most of the leachable form (“transferable") phosphorus in the totally ground sediment did not participate in the marine biogeochemical cycling. Furthermore, a synchronous survey on benthos showed that the biomass of meio and macro benthos exhibited good positive correlation with the leachable form of phosphorus in the natural grain sizes sediment, but poorer correlation with the leachable form (“transferable") phosphorus in the totally ground sediment, indicating that transferable phosphorus in marine sediment is the leachable form of phosphorus in the natural grain sizes sediments, and is not the previously known leachable form (“transferable") phosphorus obtained from the totally ground sediment.

Pollen Assemblage Features of Modern Water Samples from the Shiyang River Drainage, Arid Region of China

Pollen analysis of 30 modem water samples from the Shivang River, an internal river system located between the Tengger and Badain Jaran deserts, Northwest China was carried out to examine the river's capacity to carry pollen and spores, and to assess the contribution of the water-borne pollen to pollen assemblages in lake sediments at the end of the river system. Results indicate the pollen assemblages in water samples consist of both local and upland pollen. Percentages of upland pollen reach 30% - 60%, and pollen assemblages in water samples do not indicate the nature of local vegetation at the sampling sites. Fluvial currents have the capacity to transport large quantities of pollen long distances, and the contribution of this fluvial transported pollen is relatively high, For example, percentages of Picea Dietr. pollen in water samples at sampling sites 130 km and 145 km away from Picea forests reach 16.5% and 7.7%, respectively. Fluvial pollen transport occurs primarily during flood periods, and pollen concentrations from the flood samples are 17.1 - 12.5 times those from normal fluvial flow. Reservoirs affect pollen transportation since pollen is deposited at reservoir inlets and pollen concentrations are much reduced at reservoir outlets. Human activity can thus change natural features of pollen transportation and deposition. The main factors influencing pollen concentrations and assemblages are sampling time, sampling location, and rainfall intensity.

Coagulation of micro-polluted Pearl River water with IPF-PACls

Water samples collected from early March 2001 to the end of April 2002 at the branch of Pearl River around the Guangzhou City were analyzed for its micro-polluted characteristics. The coagulation behavior of polyaluminum chlorides(PACls) was then examined focusing on the effect of primary water quality and speciation distribution. The results showed that PACls exhibit better coagulation efficiency than alum in accordance with the different speciation. The turbidity removal property of PACls is evidently better than alum at low dosage. While in neutral zone(about 6.5—7.5), the turbidity removal of PACls decreases owing to the restabilization of particles at higher dosage. The organic matters in raw water exhibit marked influence on coagulation. In acidic zone, organic matters complex with polymer species and promote the formation of flocs. With an increase in pH, the complexation of organics with polymer species gradually decreases, and the removal of organics mainly depends on adsorption. The effect is evidently improved with the raise of B value.

Determination of volatile organic compounds in river water by solid phase extraction and gas chromatography

A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile organic compound(VOC) from the Buriganga River water of Bangladesh. The method was applied to detect the benzene, toluene, ethylbenzene, xylene and cumene(BTEXC) in the sample collected from the surface or 15 cm depth of water. Two hundred ml of n hexane pretreated and filtered water samples were applied directly to a C 18 SPE column. BTEXC were extracted with dichloromethane and average concentrations were obtained as 0 104 to 0 372 μg/ml. The highest concentration of benzene was found as 0 372 μg/ml with a relative standard deviation(RSD) of 6 2%, and cumene was not detected. Factors influencing SPE e.g., adsorbent types, sample load volume, eluting solvent, headspace and temperatures, were investigated. A cartridge containing a C 18 adsorbent and using dichloromethane gave better performance for extraction of BTEXC from water. Average recoveries exceeding 90% could be achieved for cumene at 4℃ with a 2 7% RSD.

A numerical study of summertime expansion pattern of Changjiang (Yangtze) River diluted water

Observations show that during summer especially in August, the northward expansion of the Changjiang（Yangtze） River diluted water （CRDW） is blocked in the vicinity of the Changjiang Estuary. To explain this phenomenon, Princeton ocean model （POM） is applied to simulate the summertime expansion pattern of CRDW. Numerical experiments show that to the north of the Changjiang Estuary, a tide-induced temperature front of a cold water centered at （34°N, I22.5°E） plays the key role in determining the expansion pattern of CRDW. This front splits the CRDW into two parts： the main part expands northeastward, and the other small part expands northwestward off the coast of Jiangsu Province, China.

Rare earth elements in tropical surface water,soil and sediments of the Terengganu River Basin,Malaysia

The 14 stable rare earth element(REE) concentrations and distribution patterns were investigated for surface waters(n=51),soils(n=52) and sediments(n=42) from the tropical Terengganu River basin,Malaysia.The chondrite normalized REE patterns of soils developed on four geological units showed enrichment of LREE,a pronounced negative Eu,and depletion of HREE with an enrichment order granite>>metasedimentary>alluvium>volcanic.The REE patterns in sediments reflected the soil REE patterns with an ove...

An Observational Analysis of the Relationship Between Wind and the Expansion of the Changjiang River Diluted Water during Summer

This paper presents an analysis of the impact of wind on the transport of the Changiiang River Diluted Water （CRDW） in August by using the salinity data col- lected on two zonal sections near Cheju-do. Based on the climatological mean conditions and four extreme events, the analysis indicates that wind-induced Ekman transport plays an important role in the extension of the CRDW. The strong northeastward Ekman transport induced by southeasterly wind in 1996, 2003, 2004, and 2006 pushes the core of the CRDW to the sea adjacent to Cheju-do. A comparison of the wind variation before observation among these four extreme events indicates that the expan- sion pattern of the CRDW is primarily changed by synop- tic variation with tirnescales of days to weeks, such as during a typhoon. The weak eastward extension of the CRDW in 2004, accompanied with a relatively strong southerly wind, implies that the oceanographic state （e.g., the depth of halocline） may strongly affect the impact of wind on the extension of the CRDW.

Relationships Between River Water Quality and Landscape Factors in Haihe River Basin, China: Implications for Environmental Management

River water plays a key role in human health, and in social and economic development, and is often affected by both natural factors and human activities. An in-depth understanding of the role of these factors can help in developing an effective catchment management strategy to protect precious water resources. This study analyzed river water quality, patterns of terrestrial and riparian ecosystems, intensity of agricultural activities, industrial structure, and spatial distribution of pollutant emissions in the Haihe River Basin in China for the year of 2010, identifying the variables that have the greatest impact on river water quality. The area percentage of farmland in study area, the percentage of natural vegetation cover in the 1000-m riparian zone, rural population density, industrial Gross Domestic Product(GDP)/km^2, and industrial amino nitrogen emissions were all significantly correlated with river water quality(P < 0.05). Farming had the largest impact on river water quality, explaining 43.0% of the water quality variance, followed by the coverage of natural vegetation in the 1000-m riparian zone, which explained 36.2% of the water quality variance. Industrial amino nitrogen emissions intensity and rural population density explained 31.6% and 31.4% of the water quality variance, respectively, while industrial GDP/km^2 explained 26.6%. Together, these five indicators explained 67.3% of the total variance in water quality. Consequently, water environmental management of the Haihe River Basin should focus on adjusting agricultural activities, conserving riparian vegetation, and reducing industrial pollutant emissions by optimizing industrial structure. The results demonstrate how human activities drive the spatial pattern changes of river water quality, and they can provide reference for developing land use guidelines and for prioritizing management practices to maintain stream water quality in a large river basin.

Groundwater and surface water interactions in an alluvial plain, Tuul River Basin, Ulaanbaatar, Mongolia

Drinking water supplies in Ulaanbaatar, the capital of Mongolia, are completely dependent on groundwater sourced from pumping wells located in an alluvial plain of the Tuul River which flows through Ulaanbaatar. The interaction between groundwater in the alluvial plain and river surface water was investigated using a hydrological and multi-tracers approach. The observed groundwater contour map clearly shows that the Tuul River recharges the floodplain groundwater and groundwater flows from east to west. The similarity of chemical and stable isotopic compositions suggests that groundwater is mainly recharged by Tuul River water in the vicinity of the river. In addition, considering groundwater contours and chemical composition, groundwater in the northern and southern mountain sides contribute to floodplain groundwater. Stable isotopic information suggests that winter season precipita- tion also contributes to the groundwater, because groundwater in a specific region has a considerably lower isotopic ratio. Using the End Member Mixing Analysis applying oxygen-18, SiO2 and HCO3 as tracers, the contribution ratios of the Tuul River, groundwater in the northem and southern mountain regions, and winter season precipitation to floodplain groundwater are esti- mated to be 58% to 85%, 1% to 54%, 0% to 16%, and 0% to 12%, respectively.

Turning mechanism problems of the Changjiang River diluted water

Some main ideas about the turning of the Changjiang River diluted water (CDW) and their deficiencies are reviewed in this paper. According to a large number of observation data it is pointed out that the turning phenomena of the CDW are related not only to the discharge of the Changjiang River but also to the sea surface slope and wind stress curl in the southeast coast of China. Exsistence of the sea surface slope reflects essentially the effect of the Taiwan Warm Currc (TWC) on the turning of the CDW.

Evolutionary trend of water cycle in Beichuan River Basin of China under the influence of vegetation restoration

The study aims to identify a suitable site for open and bore well in a farmhouseusing ground magnetic survey in south India.It also aims to define depth to granitoid and structural elements which traverse the selected area.Magnetic data(n=84)measured,processed and interpreted as qualitative and quantitatively.The results of total magnetic intensities indicate that the area is composed of linear magnetic lows trending NE-SW direction and circular to semi-circular causative bodies.The magnetic values ranged from-137 nT to 2345 nT with a mean of 465 nT.Reduction to equator shows significant shifting of causative bodies in the southern and northern directions.Analytical signal map shows exact boundary of granitic bodies.Cosine directional filter has brought out structural element trending NE-SW direction.Results of individual profile brought to light structurally weak zone between 90 m and 100 m in all the profile lines.Sudden decrease of magnetic values from 2042 nT to 126 nT noticed in profile line 6 between 20 m and 30 m indicates fault occurrence.Magnetic breaks obtained from these maps were visualized,interpreted and identified two suitable sites for open and bore well.Radially averaged power spectrum estimates depth of shallow and deep sources in 5 m and 50 m,respectively.Euler method has also been applied to estimate depth of granitoid and structural elements using structural indexes 0,1,2,and 3 and found depth ranges from<10 m to>90 m.Study indicates magnetic method is one of the geophysical methods suitable for groundwater exploration and site selection for open and borewells.

Maintaining healthy rivers and lakes through water diversion from Yangtze River to Taihu Lake in Taihu Basin

On the basis of the Taihu water resources assessment, an analysis of the importance and rationality of the water diversion from the Yangtz,e River to Taihu Lake in solving the water problem and establishing a harmonious eco-environment in the Taihu Basin is performed. The water quantity and water quality conjunctive dispatching ＇decisi＂ofi-makifig support system, which ensures flood control, water supply and eco-aimed dispatching, is built by combining the water diversion with flood control dispatching and strengthening water resources monitoring and forecasting. With the practice and effect assessment, measures such as setting the -integrated basin management format, further developing water diversion and improving the hydraulic engineering projects system and water monitoring system are proposed in order to maintain healthy rivers and guarantee the development of the economy and society in the Taihu Basin.

Modified Saint-Venant equations for flow simulation in tidal rivers

Flow in tidal rivers periodically propagates upstream or downstream under tidal influence. Hydrodynamic models based on the Saint-Venant equations （the SVN model） are extensively used to model tidal rivers. A force-corrected term expressed as the combination of flow velocity and the change rate of the tidal fevel was developed to represent tidal effects in the SVN model. A momentum equation incorporating with the corrected term was derived based on Newton＇s second law. By combing the modified momentum equation with the continuity equation, an improved SVN model for tidal rivers （the ISVN model） was constructed. The simulation of a tidal reach of the Qiantang River shows that the ISVN model performs better than the SVN model. It indicates that the corrected force derived for tidal effects is reasonable; the ISVN model provides an appropriate enhancement of the SVN model for flow simulation of tidal rivers.

Analysis of ecological effects of comprehensive treatment in the Tarim River Basin using remote sensing data

Based on multi-type,multi-temporal remote sensing data,we have monitored recent changes in cultivated land use and vegetation,in sandy areas and salinized desertification in the Green Corridor zone of the main channel of the Tarim River Basin.The results of our investigation show that the ecological environment in the Green Corridor of the main channel of the Tarim River Basin has conspicuously improved from 2002 to 2004.These improvements show up largely in such aspects as an increase in the rate of vegetation cover,a reduction in desertification land areas and a weakening in the intensity of sandy and the salinized land.On the other hand,the cultivated area in the Tarim River Basin significantly increased from 2002 to 2004.The rate of growth in cultivated areas during this period was significantly higher than that from 1999 to 2002.The increase in the use of irrigation resulting from the substantial increase in cultivated areas has a long-term potential restraining effect on the restoration of ecological functions of the Tarim River.

Efficiency and mechanism of pretreatment on water supply in reservoirs of Yellow River by subsurface constructed wetlands

In order to improve the source water quality of drinking water and mitigate the load of drinking water treatment plant, a pilot test was conducted with integrated horizontal flow constructed wetlands to pretreat the water supply in the reservoirs of Yellow River. Resuhs show that under the hydraulic loading rate of 4 m^3/（ m^2 · d）, the average removal rates of chemical oxygen demand （COD）, total nitrogen （TN）, ammonium nitrogen （ NH4 ^＋ - N）, nitrate nitrogen （ NO3 ^- - N）, nitrite - nitrogen （ NO2^ - - N） and total phosphorus （TP） in the horizontal flow constructed wetlands are 49. 68% , 53.01%, 48.48%, 53.61% , 62. 57% and 49. 56%, re- spectively. The study on purifying mechanism of the constructed wetlands indicates that the disposal of contamination by subsurface wetlands is the combined actions of physical chemistry, plants and microorganism.

Cu behaviors and effects of mine drainage in Kosaka River,Hokuroku mining district,Northeast Japan

Focusing on the origin of the heavy metal,this study aims to build an imputed method to estimate the heavy metal content in river water by making a distinction between the heavy metal of natural origins and that caused by human activities.Supported by GIS,Kosaka watershed within the Hokuroku basin was divided into several sub-watershed polygons and the outflows of water and Cu were calculated for each polygon.Compared with the natural origin,the dominant Cu emissions affected the river water more significantly in local.Based on the mass balance closure,the heavy metal content of Cu in the Kosaka River was estimated by the conflux accumulation of tributaries and mine drainages.The estimated Cu concentrations were checked by comparing with the actually measured values at monitoring points along the Kosaka River and the results are coincidence with each other in general.It is revealed that the mainstream water quality could be estimated by seizing the water quality of upstream tributaries and human drainages.

Anthropogenic disturbance of aquatic biodiversity and water quality of an urban river in Penang, Malaysia

Malaysia's rapid economic and demographic development have placed negative pressure on its water supplies and the quality of the Juru River, which is close to the nation's capital and its major source of water. Healthy aquatic ecosystems are supported by physicochemical properties and biological diversity. This study evaluated the anthropogenic impacts on aquatic biodiversity, especially plankton, fish, and macrobenthos, as well as the water quality of the Juru River in the Penang area. Aquatic biodiversity and river water parameters were collected from ten sampling stations along the Juru River. Seven variables were used to assess the physicochemical environment: pH, temperature, total suspended solids (TSS), salinity, dissolved oxygen (DO), biochemical oxygen demand (BOD), and chemical oxygen demand. At each sampling station, the total number of plankton, fish, and macrobenthic taxa were counted and analyzed. The relationships between the physicochemical parameters and aquatic biodiversity were investigated with biotypological analysis, principal component analysis, hierarchical cluster analysis, and linear regression analysis. These analyses showed that the richness and diversity indices were generally influenced by salinity, temperature, TSS, BOD, and pH. The data obtained in this study supported the bioindicator concept. The findings, as they related to scientifically informed conservation, could serve as a model for Juru River management, as well as for river management throughout Malaysia and other tropical Asian countries.

Observational characteristics and dynamic mechanism of low-salinity water lens for the offshore detachment of the Changjiang River diluted water in August 2006

The Changjiang River diluted water(CDW)spreads into the East China Sea(ECS)primarily in a plume pattern,although in some years,low-salinity water lenses(LSWLs)detach from the main body of the CDW.In-situ observations indicate that in August 2006,a LSWL detached from the main body of the CDW near the river mouth.In this paper,the effects of winds,tides,baroclinity and upwelling on LSWLs are explored with a threedimensional model.The results show that:(1)winds play a crucial role in these detachment events because windinduced northerly Eulerian residual currents impose an uneven force on the CDW and cut it off,thus forming a LSWL;(2)upwelling carries high-salinity water from the lower layer to the upper layer,truncating the low-salinity water tongue vertically,which is conducive to the detachment and maintenance of LSWLs;and(3)upwelling during the evolution of a LSWL is caused by the combined effects of winds and tides.The influences of windinduced upwelling are mainly near the shore,whereas the upwelling along the 30 m isobath is predominantly affected by tides,with the effect increasing from neap tide to spring tide.

Influence of Wetland Self-purification Capacity on the Utilization of Water Resources——A Case Study of the Project for Recycling Yanshan River Water

[ Objective] The study aims to resolve water resource problem availably. [ Method] On the basis of wetland self-purification capacity, Yanshan River water was purified by Xixi Wetland, and the feasibility of using treated Yanshan River water for urban greening and watering road was analyzed. [Result] Compared with direct utilization of tap water, it is more economic to recycle Yanshan River water purified by Xixi Wetland for urban greening and watering read, with obvious economic, ecological and social benefits, so it is an effective method to address shortage of water resources and is worth spreading. [ Conclusion] It is feasible to use Yanshan River water purified by Xixi Wetland for urban greening and watering read.