Assessment of Groundwater Quality in the Jajrood River Basin, Tehran, Iran: A Coupled Physicochemical and Hydrogeochemical Study

Background: The physicochemical composition of groundwater is affected by the quantity and quality of surrounding aquifers which are in turn recharging from adjacent river waters. Methods: In the present study, 20 surface and 16 groundwater samples were collected in pre- and post-monsoon season from the Jajrood River basin, Tehran, Iran. The samples were analyzed for 18 physicochemical water quality characteristics to assess the river and groundwater qualities. Hydrogeochemical analyses of groundwater samples were also performed to determine the Water Quality Index (WQI) for drinking and evaluate factors governing the water quality characteristic in the study area. Accordingly, the Piper diagram and Gibbs and Chadha plots were drawn to assess seasonal variations in hydrochemical facies and processes in the basin. Subsurface soil samples were also examined with respect to the structure, elemental composition, and multi-elemental trace analysis. Results: Results showed the abundance of major ions in the order of Ca+2 >Na+>Mg+2>K+ for cations and HCO3- >SO42- >Cl- >NO3- >F- for anions. In general, all drinking groundwater samples met WHO permissible limits except for Chemical Oxygen Demand (COD) and HCO3-. Moreover, the water is categorized as Ca-Mg-HCO3 type. Subsurface soil analyses demonstrated quartz and calcium carbonate as the main phases of soil structure, suggesting the enrichment of groundwater with temporary hardness. Conclusion: Overall, the groundwater quality was suitable for drinking and agricultural activities.

Analysis of water quality characteristic for water distribution systems

Since governments all over the world are paying more attention to water quality in water distribution systems (WDS), a method based on mass balance and first-order chlorine decay model was proposed to assess the efficiency of WDS involving water quality (represented by residual chlorine). The concepts of surplus chlorine factor (S) for nodes in individual pipes and comprehensive surplus chlorine factor (CS) for nodes in WDS were put forward to represent the water quality characteristic of nodes in WDS based on the assumption that the structure of the pipe network and quantity of chlorine dose are definite. The proposed method was applied to two examples of WDS and sensitivity analysis regarding chlorine decay coefficient (k0) was discussed. The results indicated that values of CS for nodes in WDS are affected by the inflow of nodes, which is determined by water demand and pipe length from water sources to nodes. In addition, the value of CS increases with k0 when the inflow of the node is larger than the optimized inflow. The results verified that the deduction of S for a single pipe can be generalized to WDS, and can measure the water quality characteristics for nodes in WDS easily.

SPATIAL AND TEMPORAL DISTRIBUTION OF FISH IN THE FLOODPLAIN OF KUMBE RIVER. PAPUA

Expansion of land clearance mostly for plantation is the big issue in Indonesia including in Papua. Its effect is not only to the catchment area but it also affects fisheries resources. The stress effect occurs worsen in Kumbe River and its floodplain area by the present of introduced fish species such as snakehead (Channa striata) and nile tilapia (Oreochromis niloticus). Spatial and temporal fish distributions are important information for the sustainable fisheries resource and theirs utilization. Study on spatial and temporal fish distribution covering four types of swamp ecosystem of Kumbe River was conducted during April-September 2014 and Mei-November 2015. Explorative field survey was conducted in four different ecosystem types in Kumbe River floodplain areas. Ecological data was collected from four sampling sites in each ecosystem type during high water precipitation (April and May) and low water precipitation (August. September and November). and fish samples were collected with different mesh sizes of gillnet fishing experiment conducted in four sampling sites. Parameters measured were fish important relative index and physical and chemical water quality parameters. The results noted 18 fish species deriving from 13 families. The Arridae with its blue catfish (Neoarius graeffei) dominated almost 90% of fish catch both spatial and temporal. Hydrological dynamic seems the key of trigger factor for the spatial and temporal distribution of fish and dynamic of habitat and water quality characteristic in the floodplain of Kumbe River.

Distribusi Dan Karakteristik Kualitas Perairan Ekosistem Mangrove Pulau Kecil Taman Nasional Bunaken

Ekosistem mangrove mempunyai fungsi ekologi dan sosial ekonomi bagi masyarakat pesisir, mempertahankan fungsi ini merupakan langkah mempertahankan fungsi ekosistem disekitarnya diantaranya terumbu karang dan padang lamun. Kajian ini menganalisa kondisi kualitas perairan ekosistem mangrove yang ada pada empat pulau kecil di Taman Nasional Bunaken (Pulau Bunaken; Pulau Manado Tua; Pulau Mantehage; Pulau Nain) dan korelasi karakterisitik kualitas air pulau-pulau tersebut (suhu, salinitas, kekeruhan, total suspended solid, pH, Dissolved Oksigen, NO3-N, dan PO4-P) dengan menggunakan Principal Component Analysis (PCA), kajian ini menggunakan instrumen pengukuran kualitas air in situ dan ex situ di laboratorium. Selain itu, hasil kualitas air ini akan dibandingkan dengan baku mutu yang telah ditetapkan pemerintah pada ekosistem mangrove, hal ini sebagai bahan pertimbangan pengelolaan ekosistem mangrove dimasa yang akan datang. Hasil yang diperoleh dari kajian ini adalah kualitas air keempat pulau ini masuk dalam kategori baik dan dapat mendukung kelangsungan hidup biota yang berasosisi didalamnya. Korelasi karakteristik kualitas air sebesar 94%, faktor utama 1 (F1) 79,33% dan faktor utama 2 (F2) 14,22% dengan penciri utama suhu, PO4-P, dan salinitas, dendogram menunjukkan adanya dua tingkatan hubungan kekerabatan dimana Pulau Nain dan Pulau Manado Tua memiliki kekerabatan kondisi perairan yang sama, diikuti Pulau Bunaken dan Mantehege. Kondisi ini harus dipertahankan dan dimonitoring secara berkala mengingat Taman Nasional Bunaken banyak mendapat tekanan dari aktivitas antropogenik dan perubahan iklim global. Mangrove ecosystems have ecological and socio-economic functions for coastal communities, preserve these functions is a step to maintain the function of adjacent ecosystems including coral reefs and seagrass beds. This study analyzed the water quality conditions of mangrove ecosystem within four small islands in Bunaken National Park (Bunaken Island, Manado Tua Island, Mantehage Island and Nain Island) and water quality characteristic correlation among these islands (e.g. temperature, salinity, turbidity, total suspended solid, pH, Dissolved Oxygen, NO3-N, and PO4-P) using Principal Component Analysis (PCA), this study used laboratory in situ and ex situ water quality measurement instruments. In addition, the results of this water quality then compared with the government standard quality for mangrove ecosystem water quality, this is a consideration for the management of mangrove ecosystems in the future. The results obtained from this study shows the water quality of these four islands in the category of good and can support the existence of associate biota that live in it. The correlation of water quality characteristic was 94%, main factor 1 (F1) 79,33% and main factor 2 (F2) 14,22% with main characteristics are temperature, PO4-P, and salinity, grouping these characteristics through dendogram showed two levels of relationship where Nain Island and Manado Tua Island have the same relationship of their water condition, followed by Bunaken Island and Mantehege. This condition must be maintained and monitored regularly as Bunaken National Park is under considerable get pressure from anthropogenic activities and global climate change.

KARAKTERISTIK KUALITAS AIR DANAU LIMBOTO, PROVINSI GORONTALO

Danau Limboto terletak pada ketinggian 25 m di atas permukaan laut yang berada di Kabupaten Gorontalo, Provinsi Gorontalo. Danau ini berfungsi untuk perikanan tangkap, perikanan budi daya, dan pengendalian banjir. Kualitas air merupakan kunci penting bagi kehidupan ikan dan salah satu masukkan penting untuk pengelolaan kegiatan perikanan. Penelitian ini bertujuan untuk mengetahui keadaan kualitas air Danau Limboto. Penelitian ini dilaksanakan pada bulan Maret, Mei, September, dan Nopember 2006. Pengambilan contoh air dilakukan di lima stasiun pengamatan dengan metode survei berstrata. Hasil penelitian menunjukkan bahwa suhu, pH, alkalinitas total, oksigen terlarut, dan karbondioksida bebas Danau Limboto mendukung untuk kegiatan perikanan. Berdasarkan pada tingkat kecerahan, N-NO3, P-PO4, klorofil-a, dan kelimpahan plankton, danau ini termasuk ke dalam perairan eutrofik hingga hipertrofik (subur). Limboto Lake is located in Gorontalo District, Gorontalo Province at 25 m above sea level. The lake functions as capture and culture fisheries and flood control. Water quality is an important environmental factors for fisheries management. The objective of this research was to identify the water quality characteristic of Limboto Lake. Research was done at March, May, September, and November 2006. Water samples was taken in each research stations using survey stratified method. The results showed that temperature, pH, total alkalinity, dissolved oxygen, and free carbon dioxide were in the level of supporting the fisheries activity. Based on transparency, N-NO3, P-PO4, chlorophylla, and abundance of plankton, the lake was catagorized as eutrophic to hypertrophic waters.

Suspended sediment estimation and analysis in river basins with rice paddy fields

Suspended sediment, which is an important water quality characteristic concerning effluents from agricultural areas, was studied in relatively small rivers that drain agricultural watersheds with considerable rice paddy areas. Suspended sediment load (SL) was observed daily for thirty three months and analysed – applying data stratification. Suspended sediment prediction models were established and the effect of rice transplanting activities on the rivers' SL was estimated. Results showed that data stratification improved the discharge–SL correlation and reduced regression and curve-fitting errors, thereby improving the efficiency of the derived model equations. Clustering the months into the rice- and non-rice transplanting seasons also improved the resulting regression equations, although not statistically significantly. Suspended SL was found to be higher during the rice transplanting season and the activities contributed a considerable amount of suspended sediment during the period, supporting the conjecture that sediments come from sources other than natural soil erosion.

Ozone: its effect on coagulation and filtration

The interest in ozone for drinking water treatment in the United States has increased dramatically in recent years due to new regulations and concern over Cryptosporidium. Ozone has many benefits, however, its expense is significant and its placement in the treatment train should be chosen with a sound understanding of its effect on other unit processes. The goal of this paper is to provide an overview of the effect of ozone on the coagulation and filtration processes. This is important given the enhanced coagulation requirements of the disinfection by-product rule and the filtered water quality goals of the Partnership for Safe Water. The effect of ozone on coagulation is shown to be dependent on the coagulant type and on the water quality characteristic that is setting the optimum coagulant dose. For waters with moderate to high dissolved organic carbon (DOC) levels, the coagulant dose is set by the DOC. Ozonation converts NOM into smaller, more oxygenated compounds, e.g. oxalic acid, that exert a greater metal salt coagulant demand than the parent compounds. In this case, higher dosages of alum or ferric chloride are needed. For low DOC waters, the coagulant dose is set by the particle and the adsorbed organic matter. Ozone may react with adsorbed DOC and alter the amount and conformation of adsorbed organic matter, which can lead to a decrease in the optimum coagulant dose. Finally, because cationic polymers react with particles and large organic matter (and not the smaller compounds formed after ozonation), the optimum polyelectrolyte coagulant dose after ozonation is reduced. Ozonation prior to filtration (intermediate ozonation) is shown to be beneficial for significantly reducing filtered water particle counts by as much as an order of magnitude.