Progressively anthropogenic intrusion and increasing water demand necessitate frequent water quality monitoring for sustainability management. Unlike laborious, time consuming field-based measurements, remote sensing-...Progressively anthropogenic intrusion and increasing water demand necessitate frequent water quality monitoring for sustainability management. Unlike laborious, time consuming field-based measurements, remote sensing-based water quality retrieval proved promising to overcome difficulties with temporal and spatial coverage. However, remotely estimated water quality parameters are mostly related to visibility characteristic and optically active property of water. This study presents results of an investigated approach to derive oxygen-related water quality parameter, namely Dissolved Oxygen (DO), in a shallow inland water body from satellite imagery. The approach deduces DO levels based on interrelated optical properties that dictate oxygen consumption and release in waters. Comparative analysis of multiple regression algorithms was carried out, using various combinations of parameters;namely, Turbidity, Total Suspended Solids (TSS), Chlorophyll-a, and Temperature. To cover the wide range of conditions that is experienced by Edku coastal lake, ground truth measurements covering the four seasons were used with corresponding satellite imageries. While results show successful statistically significant correlation in certain combinations considered, yet optimal results were concluded with Turbidity and natural logarithm of temperature. The algorithm model was developed with summer and fall data (R2 0.79), then validated with winter and spring data (R2 0.67). Retrieved DO concentrations highlighted the variability in pollution degree and zonation nature within that coastal lake, as related to boundary interactions and irregularity in flow dynamics within. The approach presented in this study encourages expanded applications with space-based earth observation products for exploring non-detectable water quality parameters that are interlinked with optically active properties in water.展开更多
The need for an advanced and even far reaching phosphorus removal at municipal WWTPs may soon get stipulations in relation to a reuse of phosphorus (P). This paper discusses the possible ways to remove phosphorous fro...The need for an advanced and even far reaching phosphorus removal at municipal WWTPs may soon get stipulations in relation to a reuse of phosphorus (P). This paper discusses the possible ways to remove phosphorous from municipal wastewater. This is already an established demand in many countries. However, as P is a limited raw material, this need for a reuse of P will become an example of what now is labelled “cyclic economy”. For instance, a national demand from the German state is already put in force. In this perspective the advanced filtration techniques will play an interesting role, and most possibly a crucial role. Examples are presented from several municipal WWTPs already in operation with a final polishing treatment step based on chemical precipitation and separation of phosphorus. Typical stable discharge P levels are found at these plants at levels < 0.05 to 0.10 ppm. The new demands on phosphorus recovery will also call for modified process concepts for the WWTP;for instance, a refined biological phosphorus removal (EBP) attains more attention and he needed very low discharge levels of P, where the enhanced P-removal will include different smart filtration techniques.展开更多
Many natural disasters have recently occurred in Laos. Among them, flooding has been the greatest problem. Land use change (deforestation and urbanization) and climate change have played significant roles, and it is i...Many natural disasters have recently occurred in Laos. Among them, flooding has been the greatest problem. Land use change (deforestation and urbanization) and climate change have played significant roles, and it is important to understand the impacts of these changes on flooding. We have developed an integrated hazard map based on a combination of four hazard maps of flooding, land use change and climate change to assess hazard areas at the national scale. The hazard map was developed using the analytical hierarchy process (AHP) and a hazard index. Finally, we divided the map into four hazard area categories, which include low, medium, intermediate and high. Based on this analysis, the integrated hazard map of Laos indicates that low hazard areas cover 87.44% of the total area, medium hazard areas cover 8.12%, and intermediate and high hazard areas respectively cover 2.42% and 2% of the land area. We compared the results with historical events to confirm that the proposed methodology is valid.展开更多
With the realization of the limitations to top-down and bottom-up watershed management approaches in addressing issues associated with urbanization, a conceptual framework for a hybrid approach that tries to effective...With the realization of the limitations to top-down and bottom-up watershed management approaches in addressing issues associated with urbanization, a conceptual framework for a hybrid approach that tries to effectively integrate the advantages of the two approaches while overcoming their respective limitations, grass root watershed management model (GWAM), was proposed and presented. This paper presents the details of implementation and validation of GWAM at Shawsheen River watershed in Massachusetts, USA. An investigation on the major components of GWAM, a common platform to conduct the management, a partnership of two major stakeholder groups from government and non-governmental organizations, and a facilitation mechanisms were carried out in detail to gain the needed understanding on structure, process and function of a successful GWAM. Also the decision making process in addressing three major urban watershed issues;flooding, habitat and aquatic life impairment, and bacterial impairment, were examined through a set of cyclic steps. Based on the lessons learned, GWAM was enhanced as a general hybrid model. The most important challenge in sustaining GWAM was to keep differently motivated stakeholders together. As revealed in the Shawsheen watershed, science should play a key role in keeping differently motivated stakeholders together by providing needed facts, understandings, data, and knowledge. When scientifically sound solutions are vetted through a process of public involvement that supports appropriate regulatory actions, the most effective environmental decisions can be made.展开更多
As a part of the National Water Development Authority (NWDA) proposal, the linking between Pennar and Cauvery is put forth with a single purpose of conserving water to the maximum extent possible. The present study co...As a part of the National Water Development Authority (NWDA) proposal, the linking between Pennar and Cauvery is put forth with a single purpose of conserving water to the maximum extent possible. The present study covers with land use/land cover (LU/LC) along the alignment study area 17215.68 sq·km. All the details of these features have been studied using IRS-P6, LISSIII data to analyze the effect of land use and land cover. The land use and land cover data are classified into 9 categories such as crop land, current fallow, forest, plantations, built-up land, water bodies, scrub land, sandy area and others. The total area going to be capsized is 17215.68 sq·km out of which 10105.96 sq·km is proposed command area. The 244 villages have to be rehabilitated due to this canal whereas about 4597 villages will enjoy the fruits of this canal in the form of drinking water, ground water recharge and as an additional source of irrigation as well. The study indicated current fallow land of 5340.14 km2 and 6307.98 km2 of cropland can be brought under cultivation which is more than what NWDA estimated land that can be benefitted.展开更多
In this study we explore a method which provides an insight into the effectiveness of various hydrologic models’ routing components based on their ability to accurately represent flood peak times and shapes. The meth...In this study we explore a method which provides an insight into the effectiveness of various hydrologic models’ routing components based on their ability to accurately represent flood peak times and shapes. The method is based on using Cross-Wavelet Transforms to estimate the phase (time) difference between the time series of the observed and the simulated discharges. In this article we evaluate two routing components, the Routing Application for Parallel Computation of Discharge (RAPID), which is based on the simplified Muskingum routing method, and the routing component of the non-linear Hillslope-Link hydrologic Model (HLM) produced in the Iowa Flood Center (IFC). Both routing components are driven by the same source of runoff and used the same channel network to ensure that the discrepancies between the simulated stream discharges are due to channel routing alone. We also explore the suitability of different wavelet shapes for our application, and how the difference in wavelet shape can affect our evaluation results. Unlike the conventional statistical skill scores used to evaluate model performance (e.g. Root Mean Squared Error, correlation coefficient, and Nash Sutcliff efficiency index), which give an estimate of the overall hydrograph performance, our method conveniently provides time-localized information with higher resolution at peak location. We perform our evaluation at multiple stream gauge locations, covering a wide range of scales (700 to 16,862 km2), located in the eastern part of the state of Iowa. Our results show that the proposed wavelet method is effective in evaluating the performance of the routing components in simulating peak times across spatial scales. Generally, the non-linear routing method employed in the HLM outperformed the Muskingum based method employed in RAPID. In addition, our results suggest that the Paul wavelet is more effective in detecting and separating individual peaks than the Morlet wavelet, which in turn leads to a more accurate evaluation of the routing components.展开更多
Population growth, urbanization, water resources pollution, environmental awareness, uneven distribution of water resources and water scarcity have necessitated water reuse especially in arid and semi-arid countries. ...Population growth, urbanization, water resources pollution, environmental awareness, uneven distribution of water resources and water scarcity have necessitated water reuse especially in arid and semi-arid countries. Influent and effluent data of chemical and biological analyses from four wastewater treatment plants (WWTPs) in the Sedibeng district municipality (SDM) were used to assess the viability of water reuse. Available worldwide water reuse criteria of Water Reclamation Plants (WRPs) for different reuse options were used to characterize the SDM’s four WWTPs for potable water, power and steel industrial water reuse. Only WWTP4 does not meet the influent design criteria of the New Goreangab WRP in Windhoek, Namibia of 43 mg/l and the DWAF general limit of discharge of 75 mg/l used by Beaufort West WRP in South Africa for COD. WWTP2 and 4 do not meet the DWAF general limit of 25 mg/l for suspended solids. Some of the water quality parameters of the effluents from these plants were non-compliant to the requirements for reuse in power generation and steel manufacturing. However, the implementation of advance treatment technologies such as membrane or advanced oxidation processes (AOPs) as part of the treatment train in a potential WRP would address the water quality issues. Water reclamation of SDM effluent either through direct (DPR) or indirect potable (IPR) water reuse, power generation and steel manufacturing industry has the potential of reuse in the Southern Gauteng region. The success of the selected option would be depended on cost effectiveness, stakeholder commitment and public acceptance of the reuse strategy.展开更多
In this study, an attempt was made to develop a new simplified groundwater vulnerability to contamination index (SGVI). Nine experts in the fields of groundwater, surface water, soil, landuse and GIS were interviewed ...In this study, an attempt was made to develop a new simplified groundwater vulnerability to contamination index (SGVI). Nine experts in the fields of groundwater, surface water, soil, landuse and GIS were interviewed to develop the new index. They were asked to agree on new parameters that could be used to investigate groundwater vulnerability. Data about such parameters must be affordable and inexpensive. Subsurface parameters were excluded due to the fact that most researchers might not have adequate data about them. The experts agreed that depth to groundwater, soil texture, lineament density, rainfall, topographic slope, drainage density and landuse/land cover parameters should be included in the new vulnerability index. The experts were also asked to give a weight and the ratings for each parameter. The weights given by the experts were subjected to AHP analysis to determine the exact weight for each parameter. An area of 3200 km2 in the northern part of Jordan was selected to test the SGVI. The final map of the SGVI showed that most of the area (more than 96%) had moderate-low and moderate-high vulnerability to contamination. The new index was also subjected to statistical analysis, map removal test and map removal sensitivity analysis. The outcomes of these analyses showed that the new index was applicable and could be used in areas where subsurface data was limited or not available.展开更多
Microalgae are emerging as one of the most promising long-term sustainable sources of renewable energy. Studies were conducted on two freshwater Chlorophytes, Chlorella vulgaris and Scenedesmus obliquus to evaluate he...Microalgae are emerging as one of the most promising long-term sustainable sources of renewable energy. Studies were conducted on two freshwater Chlorophytes, Chlorella vulgaris and Scenedesmus obliquus to evaluate heterotrophic growth rate and biomass productivity in filter-sterilized defined medium (BG 11) and municipal wastewater, both with varying concentrations of nitrogen (N). For each isolate, cultures were separately incubated in triplicate at room temperature with constant agitation on a shaker at 150 rpm for 9 days. In 0.25 mg N/L BG11 medium, the growth rate and biomass productivity of C. vulgaris were 0.28 day<sup>-1</sup> and 3.5 g·L<sup>-1</sup>, respectively. In wastewater, the same amount of N addition resulted in a higher growth rate 0.44 day<sup>-1</sup> and associated biomass productivity of 4.96 g·L<sup>-1</sup>. Increasing N levels to 0.5 mg N/L in BG11 caused an increase in growth rate (0.37 day<sup>-1</sup>) and biomass productivity (4.28 g·L<sup>-1</sup>), while the increase in N in wastewater caused growth to decline to 0.32 day<sup>-1</sup> with decreased biomass productivity of 2.19 g·L<sup>-1</sup>. A further increase in N to 1.0 mg N/L in BG11 caused an increase in the growth rate (0.43 day<sup>-1</sup>) and a decrease in biomass productivity (3.64 g·L<sup>-1</sup>), while in wastewater, growth rate and productivity of C. vulgaris were 0.32 day<sup>-1</sup> and 2.31 g·L<sup>-1</sup>, respectively. Overall, C. vulgaris grew faster and produced greater biomass than S. obliquus under comparable conditions. Based on high growth rate and biomass productivity of C. vulgaris, it could be a potential candidate for further consideration for simultaneous wastewater treatment and biofuel production.展开更多
The operating capacity of the Abidjan’s groundwater became insufficient. The deficit in drinking water resources in the District of Abidjan remains the major concern of the decision maker. The Aghien lagoon stands as...The operating capacity of the Abidjan’s groundwater became insufficient. The deficit in drinking water resources in the District of Abidjan remains the major concern of the decision maker. The Aghien lagoon stands as one of the most interesting alternatives. However, studies show the levels of pollutions of this resource without lighting out on the causes and sources of these pollutions. The present study extends over the entire catchment of the Aghien lagoon which reveals the presence of urban areas and agricultural activity areas. This raises real concerns for the Ivorian authorities. This study suggests making cartography of the risk levels of pollution on the Aghien lagoon by the surface runoff on the watershed to enlighten the decision-makers on the possible measures to be taken for the protection of this resource. It emerges from it that the risk of contamination of the lagoon is very likely. Agricultural and domestic best practices inside the pouring pond are compulsory to fight against the pollutions of this resource.展开更多
Iraq is one of the riparian countries within basins of Tigris-Euphrates Rivers in the Middle East region. The region is currently facing water shortage problems due to the increase of the demand and climate changes. I...Iraq is one of the riparian countries within basins of Tigris-Euphrates Rivers in the Middle East region. The region is currently facing water shortage problems due to the increase of the demand and climate changes. In the present study, average monthly water flow measurements for 15 stream flow gaging stations within basins of these rivers in Iraq with population growth rate data in some of its part were used to evaluate the reality of the current situation and future challenges of water availability and demand in Iraq. The results showed that Iraq receives annually 70.92 km3 of water 45.4 and 25.52 km3 from River Tigris and Euphrates respectively. An amount of 18.04 km3 of the Tigris water comes from Turkey while 27.36 km3 is supplied by its tributaries inside Iraq. The whole amount of water in the Euphrates Rivers comes outside the Iraqi borders. Annual decrease of the water inflow is 0.1335 km3·year-1 for Tigris and 0.245 km3·year-1 for Euphrates. This implies that the annual percentage reduction of inflow rates for the two rivers is 0.294% and 0.960%, respectively. Iraq consumes annually 88.89% (63.05 km3) of incoming water from the two rivers, where about 60.43% and 39.57% are from Rivers Tigris and Euphrates respectively. Water demand increases annually by 1.002 km3, of which 0.5271 km3 and 0.475 km3 are within Tigris and Euphrates basins respectively. The average water demand in 2020 will increase to 42.844 km3·year-1 for Tigris basin and for Euphrates 29.225 km3·year-1 (total 72.069 km3·year-1), while water availability will decrease to 63.46 km3·year-1. This means that the overall water shortage will be restricted to 8.61 km3.展开更多
Wise utilization of water resources is becoming very important as world faces water crises. The main objective of this study was to investigate the rural water supply systems with case study in Adama area, in central ...Wise utilization of water resources is becoming very important as world faces water crises. The main objective of this study was to investigate the rural water supply systems with case study in Adama area, in central Ethiopia. Both quantitative and qualitative data were collected and analyzed. Four sample water schemes were selected and totally 148 (63 were female) representative households were selected for answering the questionnaires. Key informant interviews and group discussions were also conducted. The study assessed issues such as community participation, water committee empowerment, management and governance of water supply schemes, women participation, functional status of water supply scheme, sanitation and hygiene issues, external support, and monitoring system of water supply schemes. The findings indicated that the community participation in planning and implementation was very good while monitoring mechanism of operation and management as well as community participation on choice of technology was poor. The water schemes were located at reasonable distances i.e. less than 2 km in most cases and the time taken for round trip to fetch water from source was less than or equal to 30 minutes in most cases, however the queuing time was more than an hour. The water supply was inadequate as only about 15% of beneficiaries could get 20 liters of water per day per capita. The water sources were exposed in many cases to human waste, wild life, livestock and uncontrolled flooding. Sanitary practices in the study area were poor as only about 3.4% had ventilated and improved pit latrine and open pit and/or open field defecation were widely practiced.展开更多
This study assessed the influence of a freshwater pulse on selected physico-chemical and biological variables in a permanently open freshwater deprived southern African estuary. In the absence of the freshwater pulse ...This study assessed the influence of a freshwater pulse on selected physico-chemical and biological variables in a permanently open freshwater deprived southern African estuary. In the absence of the freshwater pulse a reverse gradient in salinity was evident with hypersaline (salinity > 40) conditions prevailing in the upper reaches of the estuary. Total chlorophyll-a (chl-a) concentration during this period ranged from 0.25 to 0.60 μg·l-1. The mean total zooplankton abundance and biomass in the absence of freshwater during the daytime was 666 ind·m-3 (SD ± 196) and 12.4 mg·dwt·m-3 (SD ± 3.3), respectively. During the night time the mean total zooplankton abundance was 3121 ind·m-3 (SD ± 1203) and the biomass 21.8 mg·dwt·m-3 (SD ± 196). The total zooplankton abundance during the dry season was numerically dominated by the copepod nauplii and the calanoid copepod, Pseudodiaptomus hessei, which contributed up to 76% of the total zooplankton counts. The freshwater pulse was associated with the establishment of a horizontal gradient in salinity along the length of the estuary and a significant increase in the total chl-a concentration (range from 0.74 to 11.75 μg·l-1) and zooplankton biomass (range from 23.7 to 76.6 mg·dwt·m-3) (p ally, there was a marked increase in the total zooplankton abundances and biomass within the estuary. A distinct shift in the zooplankton community composition was evident with the copepod, Acartia longipatella numerically dominating the zooplankton counts.展开更多
The paper discusses assessment of various chemical constituents present in groundwater besides morphology, and land form characteristics of twin micro-watersheds (viz., Melekote and Rajaghatta) Dodballapur Taluk, (Kar...The paper discusses assessment of various chemical constituents present in groundwater besides morphology, and land form characteristics of twin micro-watersheds (viz., Melekote and Rajaghatta) Dodballapur Taluk, (Karnataka) coming under semi-arid climatic zone. Farmers who are mainly depending on agricultural yields for their living are disappointed due to vagaries of monsoons and undependable rainfall. This is particularly so in arid and semi-arid regions. These regions suffer from water scarcity, soil degradation, low crop yield, high soil erosion and gradual depletion of soil fertility. All these factors culminate in planning for conservation and storage of water in small watersheds for future needs, i.e., during drought conditions. In many areas, it is observed that the water table levels are declining resulting in problems of increased concentration of solutes and deterioration of groundwater quality. All aspects of hydrological studies are covered in relation to watershed management in order to formulate strategies for sustainable agricultural development. Morphometry, landform and topography play an important role in understanding the hydrological response of any watershed. Quantitative morphometric analysis has been carried out on the watershed along with landform and topographical study.展开更多
In this study, the reproduction of the sand smelt, Atherina lagunae, from the Tunis North Lake is investigated. The smallest mature female was 39 mm total length (TL). Fifty percent of the females were mature at 58 mm...In this study, the reproduction of the sand smelt, Atherina lagunae, from the Tunis North Lake is investigated. The smallest mature female was 39 mm total length (TL). Fifty percent of the females were mature at 58 mm (TL). The yearly and monthly average gonadosomatic indexes (GSI) are presented. The average value of GSI for the 12-month period was respectively 3.02%, 2.57% and 2.8% for females, males and both sexes. The GSI began to increase in March (2.37% for females and 2.12% for males). The maximum GSI was recorded in May, 11.29% for females and 10.03% for males. The highest values were recorded between March and July, indicating the reproduction period of Atherina lagunae in the Tunis North Lake. Similar GSI values were recorded in sand smelt males from brackish lagoons of southern France.展开更多
This paper presents the grounds for an integrated approach to address endemic fluorosis in Jharkhand, India, an approach that encompasses health monitoring, community-based water systems management, and locally synthe...This paper presents the grounds for an integrated approach to address endemic fluorosis in Jharkhand, India, an approach that encompasses health monitoring, community-based water systems management, and locally synthesized hydroxyapatite, a sustainable water treatment technology. The results of this study, focusing on kinetics and sorption isotherms, demonstrate that an inexpensive, locally synthesized hydroxyapatite effectively removes fluoride from water and that the Dean Index, a measure of dental fluorosis, of school children provides a sensitive, rapid biometric to track the success of a fluoride water treatment intervention. Previous efforts to manage the fluoride problem in Jharkhand were unsuccessful, largely due to lack of accountability and inadequate community involvement. This paper explores how integrating the production of a locally synthesized hydroxyapatite with community health monitoring via the Dean Index fits into a management strategy with robust accountability mechanisms and community participation that, as historical examples suggest, is likely to succeed in Jharkhand.展开更多
Groundwater is the only source of fresh water in Gaza Strip while its inhabitants and its water consumption increased rapidly. This study aims at preserving and protecting the groundwater from any pollutants caused by...Groundwater is the only source of fresh water in Gaza Strip while its inhabitants and its water consumption increased rapidly. This study aims at preserving and protecting the groundwater from any pollutants caused by 141 industrial installations through the work of delineation of Wellhead Protection Areas (WHPA) for 47 Municipal Supply Wells in Gaza Governorate boundaries. WHPA has been determined in three different methods: Calculated Fixed-Radius Method (CFR), Analytical Method (AM), and Wellhead Analytic Ele-ment Model (WhAEM2000) which is currently used by the United States Environmental Protection Agency (EPA). These methods mainly depend on the time it takes groundwater to travel a specified horizontal dis-tance. Three well zones were delineated for each municipal production well, the first zone is 50 days time of travel (TOT), the second zone is 2 years TOT and the third zone is 5 years TOT. Different values of the ra-dius of WHPA of each well were obtained using the three methods. Consequently, several industrial installa-tions were laid inside the WHPA according to the radius values. The results show that CFR method is the weakest method because it does not take into account regional groundwater flow, causing a hydraulic gradi-ent. WHPAs identified by these methods may be either too large or too small, resulting in wellhead overpro-tection or under protection. Analytical Method incorporates hydrogeologic characteristics of the aquifer, groundwater flow, and hydrogeologic boundaries into the model. Often produces a WHPA that is smaller than the one produced using CRF. WhAEM2000 method is the best method because it uses a hydrogeologi-cal computer model of groundwater flow and it provides a more accurate delineation of the WHPA. It often produces a smaller area to manage than other methods. The study concluded that all industrial installations located in the WHPA should be carefully checked and investigated by governmental authorities. Mitigation measures for pollutants and licenses for the establishment of any new industrial installations could be based on the delineation of WHPAs using the previously mentioned methods.展开更多
Bangladesh has made impressive progress in agriculture sector in the last three decades and has almost be-come self-sufficient in food grain production. This is a tremendous achievement owing to its small territory an...Bangladesh has made impressive progress in agriculture sector in the last three decades and has almost be-come self-sufficient in food grain production. This is a tremendous achievement owing to its small territory and huge population and this was achieved through agricultural mechanization and modernization. Irrigation is one of the leading inputs has direct influence to increase yield, food grains production and plays vital role for ensuring food security in Bangladesh. The present study examined the growth of irrigated area and its impact on food grain production during last three decades. Time series data were used for the study. Differ-ent statistical methods such as mean, percentage, linear and exponential growth model were applied for get-ting meaningful findings. Various technologies have been used for irrigating crops which have contributed to rapid expansion of irrigated area. The conventional irrigation methods (Low Lift Pump, Dhone, Swing Bas-ket, Treadle Pump etc.) were replaced by modern methods (i.e Deep Tube Well and Shallow Tube Well). In addition, surface water irrigation also sharply declined, losing its importance due to lack of new surface irri-gation project and the ineffectiveness of earlier project. Groundwater covered 77 percent of total irrigated area and major (62%) extractions occurred through Shallow Tube Wells (STWs). The rapid expansion of ground water irrigation in respect to STWs irrigation was due to government’s withdrawal on restrictions on tube well setting rule, encouraging private sector and the cost effectiveness of Chinese engine which have been affordable to the small and medium farmers. Irrigated area thus, increased by about three times and cropping intensity also increased from 154 to 176 percent. Boro rice, an irrigated crop, consumed 73 percent of the total crop irrigation and contributed to a greater extent in total rice production in Bangladesh. Boro rice alone contributed to 55 percent of total food grain and was also highest (3.44 MT per hectare) compared to aus rice (1.66 MT per hectare) and aman rice (1.99 MT per hectare) per unit production. Consequently, the cultivated area of boro rice increased by 1168 to 4068 thousand hectares. The higher productivity of boro rice has almost helped the nation to meet her food requirements (about 24 Million MT). Boro rice production was highly correlated (r = .978) with irrigated area. Expansion of one hectare of irrigated area added 3.22 MT of boro rice in Bangladesh. Finally, the study suggested for expansion of irrigated areas (ground water and surface water), adoption of modern technologies and formulation of farmers’ friendly policy.展开更多
In order to study the effect of saw powder on leachate production, degradation of rubbish, COD and NH3-N concentration of leachate, three cylinder reactors for anaerobic landfill disposal were built to simulate the op...In order to study the effect of saw powder on leachate production, degradation of rubbish, COD and NH3-N concentration of leachate, three cylinder reactors for anaerobic landfill disposal were built to simulate the op-eration of landfill. In this experiment, leachate quantity, settling height of rubbish layer, COD and NH3-N concentration were monitored. The results come from experiment data analyses indicate that saw powder has strong effect on reducing leachate quantity and accelerating degradation of rubbish. In 60 days, saw powder mixed in rubbish layer can reduce 1200-1300mL leachate every liter rubbish, moreover, rubbish layer with saw powder mixed in settled more leachate than rubbish layer with no saw powder mixed in for 5cm. The ex-perimental results indicate that saw powder can reduce COD concentration of leachate and adsorb NH3-N, too.展开更多
Constructed wetlands (CWs) can achieve a high-quality wastewater treatment and a quality that meets the prescribed standard, defined by legislation on wastewater discharge. A limitation in the application of construct...Constructed wetlands (CWs) can achieve a high-quality wastewater treatment and a quality that meets the prescribed standard, defined by legislation on wastewater discharge. A limitation in the application of constructed wetlands (CWs) is the large area requirement, which limits their application. The subject matter of this research is to check the possibility of improving the efficiency of wastewater treatment and reducing the required area for constructed wetlands (CWs) by using an adequate substrate under the conditions found in Montenegro. In the described experiment, the constructed wetlands (CW) have a vertical flow system and play the role of a secondary wastewater treatment, receiving water from the existing WWTP in Podgorica after the primary treatment. These vertical flow systems reflect experience with the use of similar systems in Slovenija, Austria and Italy. Measurements to date show that the substrate plays an important role and that wastewater treatment efficacy varies significantly with respect to the type of substrate when used under the conditions available in Montenegro.展开更多
文摘Progressively anthropogenic intrusion and increasing water demand necessitate frequent water quality monitoring for sustainability management. Unlike laborious, time consuming field-based measurements, remote sensing-based water quality retrieval proved promising to overcome difficulties with temporal and spatial coverage. However, remotely estimated water quality parameters are mostly related to visibility characteristic and optically active property of water. This study presents results of an investigated approach to derive oxygen-related water quality parameter, namely Dissolved Oxygen (DO), in a shallow inland water body from satellite imagery. The approach deduces DO levels based on interrelated optical properties that dictate oxygen consumption and release in waters. Comparative analysis of multiple regression algorithms was carried out, using various combinations of parameters;namely, Turbidity, Total Suspended Solids (TSS), Chlorophyll-a, and Temperature. To cover the wide range of conditions that is experienced by Edku coastal lake, ground truth measurements covering the four seasons were used with corresponding satellite imageries. While results show successful statistically significant correlation in certain combinations considered, yet optimal results were concluded with Turbidity and natural logarithm of temperature. The algorithm model was developed with summer and fall data (R2 0.79), then validated with winter and spring data (R2 0.67). Retrieved DO concentrations highlighted the variability in pollution degree and zonation nature within that coastal lake, as related to boundary interactions and irregularity in flow dynamics within. The approach presented in this study encourages expanded applications with space-based earth observation products for exploring non-detectable water quality parameters that are interlinked with optically active properties in water.
文摘The need for an advanced and even far reaching phosphorus removal at municipal WWTPs may soon get stipulations in relation to a reuse of phosphorus (P). This paper discusses the possible ways to remove phosphorous from municipal wastewater. This is already an established demand in many countries. However, as P is a limited raw material, this need for a reuse of P will become an example of what now is labelled “cyclic economy”. For instance, a national demand from the German state is already put in force. In this perspective the advanced filtration techniques will play an interesting role, and most possibly a crucial role. Examples are presented from several municipal WWTPs already in operation with a final polishing treatment step based on chemical precipitation and separation of phosphorus. Typical stable discharge P levels are found at these plants at levels < 0.05 to 0.10 ppm. The new demands on phosphorus recovery will also call for modified process concepts for the WWTP;for instance, a refined biological phosphorus removal (EBP) attains more attention and he needed very low discharge levels of P, where the enhanced P-removal will include different smart filtration techniques.
文摘Many natural disasters have recently occurred in Laos. Among them, flooding has been the greatest problem. Land use change (deforestation and urbanization) and climate change have played significant roles, and it is important to understand the impacts of these changes on flooding. We have developed an integrated hazard map based on a combination of four hazard maps of flooding, land use change and climate change to assess hazard areas at the national scale. The hazard map was developed using the analytical hierarchy process (AHP) and a hazard index. Finally, we divided the map into four hazard area categories, which include low, medium, intermediate and high. Based on this analysis, the integrated hazard map of Laos indicates that low hazard areas cover 87.44% of the total area, medium hazard areas cover 8.12%, and intermediate and high hazard areas respectively cover 2.42% and 2% of the land area. We compared the results with historical events to confirm that the proposed methodology is valid.
文摘With the realization of the limitations to top-down and bottom-up watershed management approaches in addressing issues associated with urbanization, a conceptual framework for a hybrid approach that tries to effectively integrate the advantages of the two approaches while overcoming their respective limitations, grass root watershed management model (GWAM), was proposed and presented. This paper presents the details of implementation and validation of GWAM at Shawsheen River watershed in Massachusetts, USA. An investigation on the major components of GWAM, a common platform to conduct the management, a partnership of two major stakeholder groups from government and non-governmental organizations, and a facilitation mechanisms were carried out in detail to gain the needed understanding on structure, process and function of a successful GWAM. Also the decision making process in addressing three major urban watershed issues;flooding, habitat and aquatic life impairment, and bacterial impairment, were examined through a set of cyclic steps. Based on the lessons learned, GWAM was enhanced as a general hybrid model. The most important challenge in sustaining GWAM was to keep differently motivated stakeholders together. As revealed in the Shawsheen watershed, science should play a key role in keeping differently motivated stakeholders together by providing needed facts, understandings, data, and knowledge. When scientifically sound solutions are vetted through a process of public involvement that supports appropriate regulatory actions, the most effective environmental decisions can be made.
文摘As a part of the National Water Development Authority (NWDA) proposal, the linking between Pennar and Cauvery is put forth with a single purpose of conserving water to the maximum extent possible. The present study covers with land use/land cover (LU/LC) along the alignment study area 17215.68 sq·km. All the details of these features have been studied using IRS-P6, LISSIII data to analyze the effect of land use and land cover. The land use and land cover data are classified into 9 categories such as crop land, current fallow, forest, plantations, built-up land, water bodies, scrub land, sandy area and others. The total area going to be capsized is 17215.68 sq·km out of which 10105.96 sq·km is proposed command area. The 244 villages have to be rehabilitated due to this canal whereas about 4597 villages will enjoy the fruits of this canal in the form of drinking water, ground water recharge and as an additional source of irrigation as well. The study indicated current fallow land of 5340.14 km2 and 6307.98 km2 of cropland can be brought under cultivation which is more than what NWDA estimated land that can be benefitted.
文摘In this study we explore a method which provides an insight into the effectiveness of various hydrologic models’ routing components based on their ability to accurately represent flood peak times and shapes. The method is based on using Cross-Wavelet Transforms to estimate the phase (time) difference between the time series of the observed and the simulated discharges. In this article we evaluate two routing components, the Routing Application for Parallel Computation of Discharge (RAPID), which is based on the simplified Muskingum routing method, and the routing component of the non-linear Hillslope-Link hydrologic Model (HLM) produced in the Iowa Flood Center (IFC). Both routing components are driven by the same source of runoff and used the same channel network to ensure that the discrepancies between the simulated stream discharges are due to channel routing alone. We also explore the suitability of different wavelet shapes for our application, and how the difference in wavelet shape can affect our evaluation results. Unlike the conventional statistical skill scores used to evaluate model performance (e.g. Root Mean Squared Error, correlation coefficient, and Nash Sutcliff efficiency index), which give an estimate of the overall hydrograph performance, our method conveniently provides time-localized information with higher resolution at peak location. We perform our evaluation at multiple stream gauge locations, covering a wide range of scales (700 to 16,862 km2), located in the eastern part of the state of Iowa. Our results show that the proposed wavelet method is effective in evaluating the performance of the routing components in simulating peak times across spatial scales. Generally, the non-linear routing method employed in the HLM outperformed the Muskingum based method employed in RAPID. In addition, our results suggest that the Paul wavelet is more effective in detecting and separating individual peaks than the Morlet wavelet, which in turn leads to a more accurate evaluation of the routing components.
文摘Population growth, urbanization, water resources pollution, environmental awareness, uneven distribution of water resources and water scarcity have necessitated water reuse especially in arid and semi-arid countries. Influent and effluent data of chemical and biological analyses from four wastewater treatment plants (WWTPs) in the Sedibeng district municipality (SDM) were used to assess the viability of water reuse. Available worldwide water reuse criteria of Water Reclamation Plants (WRPs) for different reuse options were used to characterize the SDM’s four WWTPs for potable water, power and steel industrial water reuse. Only WWTP4 does not meet the influent design criteria of the New Goreangab WRP in Windhoek, Namibia of 43 mg/l and the DWAF general limit of discharge of 75 mg/l used by Beaufort West WRP in South Africa for COD. WWTP2 and 4 do not meet the DWAF general limit of 25 mg/l for suspended solids. Some of the water quality parameters of the effluents from these plants were non-compliant to the requirements for reuse in power generation and steel manufacturing. However, the implementation of advance treatment technologies such as membrane or advanced oxidation processes (AOPs) as part of the treatment train in a potential WRP would address the water quality issues. Water reclamation of SDM effluent either through direct (DPR) or indirect potable (IPR) water reuse, power generation and steel manufacturing industry has the potential of reuse in the Southern Gauteng region. The success of the selected option would be depended on cost effectiveness, stakeholder commitment and public acceptance of the reuse strategy.
文摘In this study, an attempt was made to develop a new simplified groundwater vulnerability to contamination index (SGVI). Nine experts in the fields of groundwater, surface water, soil, landuse and GIS were interviewed to develop the new index. They were asked to agree on new parameters that could be used to investigate groundwater vulnerability. Data about such parameters must be affordable and inexpensive. Subsurface parameters were excluded due to the fact that most researchers might not have adequate data about them. The experts agreed that depth to groundwater, soil texture, lineament density, rainfall, topographic slope, drainage density and landuse/land cover parameters should be included in the new vulnerability index. The experts were also asked to give a weight and the ratings for each parameter. The weights given by the experts were subjected to AHP analysis to determine the exact weight for each parameter. An area of 3200 km2 in the northern part of Jordan was selected to test the SGVI. The final map of the SGVI showed that most of the area (more than 96%) had moderate-low and moderate-high vulnerability to contamination. The new index was also subjected to statistical analysis, map removal test and map removal sensitivity analysis. The outcomes of these analyses showed that the new index was applicable and could be used in areas where subsurface data was limited or not available.
文摘Microalgae are emerging as one of the most promising long-term sustainable sources of renewable energy. Studies were conducted on two freshwater Chlorophytes, Chlorella vulgaris and Scenedesmus obliquus to evaluate heterotrophic growth rate and biomass productivity in filter-sterilized defined medium (BG 11) and municipal wastewater, both with varying concentrations of nitrogen (N). For each isolate, cultures were separately incubated in triplicate at room temperature with constant agitation on a shaker at 150 rpm for 9 days. In 0.25 mg N/L BG11 medium, the growth rate and biomass productivity of C. vulgaris were 0.28 day<sup>-1</sup> and 3.5 g·L<sup>-1</sup>, respectively. In wastewater, the same amount of N addition resulted in a higher growth rate 0.44 day<sup>-1</sup> and associated biomass productivity of 4.96 g·L<sup>-1</sup>. Increasing N levels to 0.5 mg N/L in BG11 caused an increase in growth rate (0.37 day<sup>-1</sup>) and biomass productivity (4.28 g·L<sup>-1</sup>), while the increase in N in wastewater caused growth to decline to 0.32 day<sup>-1</sup> with decreased biomass productivity of 2.19 g·L<sup>-1</sup>. A further increase in N to 1.0 mg N/L in BG11 caused an increase in the growth rate (0.43 day<sup>-1</sup>) and a decrease in biomass productivity (3.64 g·L<sup>-1</sup>), while in wastewater, growth rate and productivity of C. vulgaris were 0.32 day<sup>-1</sup> and 2.31 g·L<sup>-1</sup>, respectively. Overall, C. vulgaris grew faster and produced greater biomass than S. obliquus under comparable conditions. Based on high growth rate and biomass productivity of C. vulgaris, it could be a potential candidate for further consideration for simultaneous wastewater treatment and biofuel production.
文摘The operating capacity of the Abidjan’s groundwater became insufficient. The deficit in drinking water resources in the District of Abidjan remains the major concern of the decision maker. The Aghien lagoon stands as one of the most interesting alternatives. However, studies show the levels of pollutions of this resource without lighting out on the causes and sources of these pollutions. The present study extends over the entire catchment of the Aghien lagoon which reveals the presence of urban areas and agricultural activity areas. This raises real concerns for the Ivorian authorities. This study suggests making cartography of the risk levels of pollution on the Aghien lagoon by the surface runoff on the watershed to enlighten the decision-makers on the possible measures to be taken for the protection of this resource. It emerges from it that the risk of contamination of the lagoon is very likely. Agricultural and domestic best practices inside the pouring pond are compulsory to fight against the pollutions of this resource.
基金financially supported by Lulea University of Technology,Sweden and by“Swedish Hydropower Centre—SVC”established by the Swedish Energy Agency,Elforsk and Svenska Kraftnat together with Lulea University of Technology,The Royal Institute of Technology,Chalmers University of Technology and Uppsala University.
文摘Iraq is one of the riparian countries within basins of Tigris-Euphrates Rivers in the Middle East region. The region is currently facing water shortage problems due to the increase of the demand and climate changes. In the present study, average monthly water flow measurements for 15 stream flow gaging stations within basins of these rivers in Iraq with population growth rate data in some of its part were used to evaluate the reality of the current situation and future challenges of water availability and demand in Iraq. The results showed that Iraq receives annually 70.92 km3 of water 45.4 and 25.52 km3 from River Tigris and Euphrates respectively. An amount of 18.04 km3 of the Tigris water comes from Turkey while 27.36 km3 is supplied by its tributaries inside Iraq. The whole amount of water in the Euphrates Rivers comes outside the Iraqi borders. Annual decrease of the water inflow is 0.1335 km3·year-1 for Tigris and 0.245 km3·year-1 for Euphrates. This implies that the annual percentage reduction of inflow rates for the two rivers is 0.294% and 0.960%, respectively. Iraq consumes annually 88.89% (63.05 km3) of incoming water from the two rivers, where about 60.43% and 39.57% are from Rivers Tigris and Euphrates respectively. Water demand increases annually by 1.002 km3, of which 0.5271 km3 and 0.475 km3 are within Tigris and Euphrates basins respectively. The average water demand in 2020 will increase to 42.844 km3·year-1 for Tigris basin and for Euphrates 29.225 km3·year-1 (total 72.069 km3·year-1), while water availability will decrease to 63.46 km3·year-1. This means that the overall water shortage will be restricted to 8.61 km3.
文摘Wise utilization of water resources is becoming very important as world faces water crises. The main objective of this study was to investigate the rural water supply systems with case study in Adama area, in central Ethiopia. Both quantitative and qualitative data were collected and analyzed. Four sample water schemes were selected and totally 148 (63 were female) representative households were selected for answering the questionnaires. Key informant interviews and group discussions were also conducted. The study assessed issues such as community participation, water committee empowerment, management and governance of water supply schemes, women participation, functional status of water supply scheme, sanitation and hygiene issues, external support, and monitoring system of water supply schemes. The findings indicated that the community participation in planning and implementation was very good while monitoring mechanism of operation and management as well as community participation on choice of technology was poor. The water schemes were located at reasonable distances i.e. less than 2 km in most cases and the time taken for round trip to fetch water from source was less than or equal to 30 minutes in most cases, however the queuing time was more than an hour. The water supply was inadequate as only about 15% of beneficiaries could get 20 liters of water per day per capita. The water sources were exposed in many cases to human waste, wild life, livestock and uncontrolled flooding. Sanitary practices in the study area were poor as only about 3.4% had ventilated and improved pit latrine and open pit and/or open field defecation were widely practiced.
文摘This study assessed the influence of a freshwater pulse on selected physico-chemical and biological variables in a permanently open freshwater deprived southern African estuary. In the absence of the freshwater pulse a reverse gradient in salinity was evident with hypersaline (salinity > 40) conditions prevailing in the upper reaches of the estuary. Total chlorophyll-a (chl-a) concentration during this period ranged from 0.25 to 0.60 μg·l-1. The mean total zooplankton abundance and biomass in the absence of freshwater during the daytime was 666 ind·m-3 (SD ± 196) and 12.4 mg·dwt·m-3 (SD ± 3.3), respectively. During the night time the mean total zooplankton abundance was 3121 ind·m-3 (SD ± 1203) and the biomass 21.8 mg·dwt·m-3 (SD ± 196). The total zooplankton abundance during the dry season was numerically dominated by the copepod nauplii and the calanoid copepod, Pseudodiaptomus hessei, which contributed up to 76% of the total zooplankton counts. The freshwater pulse was associated with the establishment of a horizontal gradient in salinity along the length of the estuary and a significant increase in the total chl-a concentration (range from 0.74 to 11.75 μg·l-1) and zooplankton biomass (range from 23.7 to 76.6 mg·dwt·m-3) (p ally, there was a marked increase in the total zooplankton abundances and biomass within the estuary. A distinct shift in the zooplankton community composition was evident with the copepod, Acartia longipatella numerically dominating the zooplankton counts.
文摘The paper discusses assessment of various chemical constituents present in groundwater besides morphology, and land form characteristics of twin micro-watersheds (viz., Melekote and Rajaghatta) Dodballapur Taluk, (Karnataka) coming under semi-arid climatic zone. Farmers who are mainly depending on agricultural yields for their living are disappointed due to vagaries of monsoons and undependable rainfall. This is particularly so in arid and semi-arid regions. These regions suffer from water scarcity, soil degradation, low crop yield, high soil erosion and gradual depletion of soil fertility. All these factors culminate in planning for conservation and storage of water in small watersheds for future needs, i.e., during drought conditions. In many areas, it is observed that the water table levels are declining resulting in problems of increased concentration of solutes and deterioration of groundwater quality. All aspects of hydrological studies are covered in relation to watershed management in order to formulate strategies for sustainable agricultural development. Morphometry, landform and topography play an important role in understanding the hydrological response of any watershed. Quantitative morphometric analysis has been carried out on the watershed along with landform and topographical study.
文摘In this study, the reproduction of the sand smelt, Atherina lagunae, from the Tunis North Lake is investigated. The smallest mature female was 39 mm total length (TL). Fifty percent of the females were mature at 58 mm (TL). The yearly and monthly average gonadosomatic indexes (GSI) are presented. The average value of GSI for the 12-month period was respectively 3.02%, 2.57% and 2.8% for females, males and both sexes. The GSI began to increase in March (2.37% for females and 2.12% for males). The maximum GSI was recorded in May, 11.29% for females and 10.03% for males. The highest values were recorded between March and July, indicating the reproduction period of Atherina lagunae in the Tunis North Lake. Similar GSI values were recorded in sand smelt males from brackish lagoons of southern France.
文摘This paper presents the grounds for an integrated approach to address endemic fluorosis in Jharkhand, India, an approach that encompasses health monitoring, community-based water systems management, and locally synthesized hydroxyapatite, a sustainable water treatment technology. The results of this study, focusing on kinetics and sorption isotherms, demonstrate that an inexpensive, locally synthesized hydroxyapatite effectively removes fluoride from water and that the Dean Index, a measure of dental fluorosis, of school children provides a sensitive, rapid biometric to track the success of a fluoride water treatment intervention. Previous efforts to manage the fluoride problem in Jharkhand were unsuccessful, largely due to lack of accountability and inadequate community involvement. This paper explores how integrating the production of a locally synthesized hydroxyapatite with community health monitoring via the Dean Index fits into a management strategy with robust accountability mechanisms and community participation that, as historical examples suggest, is likely to succeed in Jharkhand.
文摘Groundwater is the only source of fresh water in Gaza Strip while its inhabitants and its water consumption increased rapidly. This study aims at preserving and protecting the groundwater from any pollutants caused by 141 industrial installations through the work of delineation of Wellhead Protection Areas (WHPA) for 47 Municipal Supply Wells in Gaza Governorate boundaries. WHPA has been determined in three different methods: Calculated Fixed-Radius Method (CFR), Analytical Method (AM), and Wellhead Analytic Ele-ment Model (WhAEM2000) which is currently used by the United States Environmental Protection Agency (EPA). These methods mainly depend on the time it takes groundwater to travel a specified horizontal dis-tance. Three well zones were delineated for each municipal production well, the first zone is 50 days time of travel (TOT), the second zone is 2 years TOT and the third zone is 5 years TOT. Different values of the ra-dius of WHPA of each well were obtained using the three methods. Consequently, several industrial installa-tions were laid inside the WHPA according to the radius values. The results show that CFR method is the weakest method because it does not take into account regional groundwater flow, causing a hydraulic gradi-ent. WHPAs identified by these methods may be either too large or too small, resulting in wellhead overpro-tection or under protection. Analytical Method incorporates hydrogeologic characteristics of the aquifer, groundwater flow, and hydrogeologic boundaries into the model. Often produces a WHPA that is smaller than the one produced using CRF. WhAEM2000 method is the best method because it uses a hydrogeologi-cal computer model of groundwater flow and it provides a more accurate delineation of the WHPA. It often produces a smaller area to manage than other methods. The study concluded that all industrial installations located in the WHPA should be carefully checked and investigated by governmental authorities. Mitigation measures for pollutants and licenses for the establishment of any new industrial installations could be based on the delineation of WHPAs using the previously mentioned methods.
文摘Bangladesh has made impressive progress in agriculture sector in the last three decades and has almost be-come self-sufficient in food grain production. This is a tremendous achievement owing to its small territory and huge population and this was achieved through agricultural mechanization and modernization. Irrigation is one of the leading inputs has direct influence to increase yield, food grains production and plays vital role for ensuring food security in Bangladesh. The present study examined the growth of irrigated area and its impact on food grain production during last three decades. Time series data were used for the study. Differ-ent statistical methods such as mean, percentage, linear and exponential growth model were applied for get-ting meaningful findings. Various technologies have been used for irrigating crops which have contributed to rapid expansion of irrigated area. The conventional irrigation methods (Low Lift Pump, Dhone, Swing Bas-ket, Treadle Pump etc.) were replaced by modern methods (i.e Deep Tube Well and Shallow Tube Well). In addition, surface water irrigation also sharply declined, losing its importance due to lack of new surface irri-gation project and the ineffectiveness of earlier project. Groundwater covered 77 percent of total irrigated area and major (62%) extractions occurred through Shallow Tube Wells (STWs). The rapid expansion of ground water irrigation in respect to STWs irrigation was due to government’s withdrawal on restrictions on tube well setting rule, encouraging private sector and the cost effectiveness of Chinese engine which have been affordable to the small and medium farmers. Irrigated area thus, increased by about three times and cropping intensity also increased from 154 to 176 percent. Boro rice, an irrigated crop, consumed 73 percent of the total crop irrigation and contributed to a greater extent in total rice production in Bangladesh. Boro rice alone contributed to 55 percent of total food grain and was also highest (3.44 MT per hectare) compared to aus rice (1.66 MT per hectare) and aman rice (1.99 MT per hectare) per unit production. Consequently, the cultivated area of boro rice increased by 1168 to 4068 thousand hectares. The higher productivity of boro rice has almost helped the nation to meet her food requirements (about 24 Million MT). Boro rice production was highly correlated (r = .978) with irrigated area. Expansion of one hectare of irrigated area added 3.22 MT of boro rice in Bangladesh. Finally, the study suggested for expansion of irrigated areas (ground water and surface water), adoption of modern technologies and formulation of farmers’ friendly policy.
文摘In order to study the effect of saw powder on leachate production, degradation of rubbish, COD and NH3-N concentration of leachate, three cylinder reactors for anaerobic landfill disposal were built to simulate the op-eration of landfill. In this experiment, leachate quantity, settling height of rubbish layer, COD and NH3-N concentration were monitored. The results come from experiment data analyses indicate that saw powder has strong effect on reducing leachate quantity and accelerating degradation of rubbish. In 60 days, saw powder mixed in rubbish layer can reduce 1200-1300mL leachate every liter rubbish, moreover, rubbish layer with saw powder mixed in settled more leachate than rubbish layer with no saw powder mixed in for 5cm. The ex-perimental results indicate that saw powder can reduce COD concentration of leachate and adsorb NH3-N, too.
文摘Constructed wetlands (CWs) can achieve a high-quality wastewater treatment and a quality that meets the prescribed standard, defined by legislation on wastewater discharge. A limitation in the application of constructed wetlands (CWs) is the large area requirement, which limits their application. The subject matter of this research is to check the possibility of improving the efficiency of wastewater treatment and reducing the required area for constructed wetlands (CWs) by using an adequate substrate under the conditions found in Montenegro. In the described experiment, the constructed wetlands (CW) have a vertical flow system and play the role of a secondary wastewater treatment, receiving water from the existing WWTP in Podgorica after the primary treatment. These vertical flow systems reflect experience with the use of similar systems in Slovenija, Austria and Italy. Measurements to date show that the substrate plays an important role and that wastewater treatment efficacy varies significantly with respect to the type of substrate when used under the conditions available in Montenegro.
