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Jino John ¹, Lins Paul Kuriakose ¹, T. Meenambal ²

Affiliations
1 Sri Krishna College of Technology, IN
2 Government College of Technology, Coimbatore, Tamilnadu, IN

Abstract

The study deals with the temperature stress distribution on concrete and fly ash concrete slabs by non linear (Quadratic Temperature Profile) method. Concrete and fly ash concrete slabs of size 1000mm x 1000mm x 150mm were cast. Cement was replaced by 10, 20, and 30 % of fly ash. M40 grade concrete was used for the study. Temperatures were measured at top, middle and bottom of the slab by using thermocouple for 7 days at every one interval from 6 am to 8pm after 28 days curing. The study shows that actual temperature distribution across the depth of slab was highly nonlinear. The temperature stresses were calculated by Quadratic Temperature Profile Method. Temperature stress gets reduced with increase in percentage of fly ash replacement.

Keywords

Fly Ash Concrete, Concrete Pavement, Non Linear Temperature Distribution, Temperature Stress, Non Linear Temperature Stress, IRC 44

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C. Rajakumar ¹, T. Meenambal ²

Affiliations
1 Department of Civil Engineering, Karpagam College of Engineering, Coimbatore-641 032, T.N., IN
2 Department of Geotechnical Engineering, Government College of Technology, Coimbatore-641013, T.N., IN

Abstract

The growing cost of traditional stabilizing agents and the need for the economical utilization of industrial and agricultural wastes has prompted an investigation into the stabilizing potential of coal ash (CA), groundnut shell ash (GSA) and bagasse ash (BA) in highly expansive soil. In this study an attempt has been made to utilize the industrial and agricultural wastes such as coal ash, groundnut shell ash and bagasse ash as a stabilizing agent. The effect of industrial and agricultural wastes under individual and combinations (equal proportion) of mix proportions on certain properties of soil such as Optimum Moisture Content (OMC), Maximum Dry Density (MDD), Unconfined Compressive (UCC) Strength and CBR has been studied. Index properties of natural soil showed that it belongs to CH in the IS classification system, soils under this group have poor engineering benefit. It has been observed that 30% of CA and 8% of GSA and BA for individual mix proportions and 12% CA + 12% GSA, 16% CA + 16% BA and 16% BA + 16% GSA for the combinations of mix proportions, are the optimum percentage that gives the maximum CBR value.

Keywords

Coal Ash, Bagassh Ash, Groundnut Shell Ash, CBR.

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C. Rajakumar ¹, T. Meenambal ²

Affiliations
1 Department of Civil Engineering, Karpagam College of Engineering, Coimbatore, Tamilnadu, IN
2 Department of Geotechnical Engineering, Government College of Technology, Coimbatore, Tamilnadu, IN

Abstract

Expansive soils show extensive volume and their strength changes at varying moisture content due to their chemical composition. This causes significant structural damage to foundations, including pavements. One way of overcoming these problems in soils is to stabilize them with admixtures. Owing to this fact, continuous researches have been carried out and still being carried out by individuals, firms and institutions on ways to improve the engineering properties of soils. The need to bring down the cost of soil stabilizers and the environmental damage has led to intense global research towards economic utilization of wastes for engineering purposes. Bagasse ash is a waste-product of the sugar refining industry. This study was carried out to determine the effect of bagasse ash utilization for road application on clay. The laboratory investigations are carried out to examine the index and engineering properties of the soil sample. The soil falls under CI category of Indian standard soil classification system. The experiments have been carried out to study the changes in the properties of soil such as plasticity characteristics, free swell index, pH, calcium carbonate content, total dissolved solids and cation exchange capacity using bagasse ash in varying percentages of 2%, 4%, 6%, 8% and 10%. The study shows promising results with effective utilization of bagasse ash in the improvement of soil strength.

Keywords

Expansive Soil, Bagasse Ash Utilisation, CBR Chemical Properties, Soil Strength.

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N. Balasundaram ¹, T. Meenambal ², N. Balasubramanium ³, R. Loganath ⁴

Affiliations
1 Department of Civil Engineering, Government College of Technology, Coimbatore-641 013, T. N., IN
2 Department of Civil Engineering, Karpagam University, Coimbatore-641 013, T. N., IN
3 Tamilnadu Water Supply and Drainage Board, TWAD Board, Coimbatore-641 013, T. N., IN
4 Department of Environmental Engineering, Government College of Technology, Coimbatore-641 013, T. N., IN

Abstract

Processing of sago generates enormous quantities of high strength wastewater requiring systematic treatment prior to disposal. The present study is an attempt to compare the three media such as polypropylene ring, rosette filter and PVC carrier, in the treatment of sago wastewater using Hybrid Upflow Anaerobic Sludge Blanket (HUASB) reactor. Three HUASB reactors each with a volume of about 4.7 L and effective volume of 4.2 L was operated and packed with the above three media separately in each reactor along with the effective microorganisms (EM) solution added in 1:1000 ratio of reactor volume. The initial OLR (Organic Loading Rate) range was about 0.75 kg.COD/m³.day and further increased. Various effluent characteristics like pH, COD, total suspended solids (TSS), VFA, alkalinity and biogas production were studied until the attainment of steady state. The pH of treated effluent during steady state condition was almost neutral for all the three reactors even though the influent had an acidic pH. The optimum HRT was found to be 10h for both polypropylene media and PVC carrier media and 8h for rosette filter media. The maximum COD and TSS removal efficiencies for the reactor packed with polypropylene were as high as 88% and 77% in HUASB reactor in the presence of effective microorganisms with an OLR of 9 kg.COD/m³.day. And for the reactor packed with rosette filter, the maximum COD and TSS removal efficiencies were 84% and 76% in HUASB reactor in the presence of effective microorganisms with an OLR of 9 kg.COD/m³.day. Similarly, for the reactor packed with PVC carrier media, the maximum COD and TSS removal efficiencies were 86% and 78% in HUASB reactor in the presence of effective microorganisms with an OLR of 9 kg.COD/ m³.day. The maximum gas production for these three reactors packed with polypropylene ring, rosette filter and PVC carrier media were 2.8 L/d, 0.66 L/d and 1.7 L/d respectively in the presence of effective microorganisms. It is found that from an overall assessment, the HUASB reactor packed with polypropylene ring has proved superior in its performance compared to the HUASB reactor with other packing media.

Keywords

Sago Wastewater, Rosette Filter, Hybrid UASB, Biogas.

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P. Shanthi ¹, P. Meena Sundari ², T. Meenambal ³

Affiliations
1 Department of Civil Engineering, Karpagam University, Coimbatore, T. N., IN
2 Department of Chemistry, Jansons Institute of Technology, Coimbatore, T. N., IN
3 Department of Civil Engineering, Government College of Technology, Coimbatore, T. N., IN

Abstract

Municipal solid waste management (MSWM) is one of the major environmental problems of Indian cities. Improper management of municipal solid waste (MSW) causes hazards to inhabitants. Various studies reveal that about 90% of MSW is disposed of unscientifically in open dumps and landfills, create problems to public health and the environment. This paper presents an assessment of the existing situation of municipal solid waste management (MSWM) in Coimbatore city. The quantity and composition of MSW vary from place to place, and bear a rather consistent correlation with the average standard of living. Field investigations were carried out for quantification, analysis of physico chemical composition, and characterization in disposal site. Studies carried out in these places have revealed that there are many shortcomings in the existing practices used in managing the MSW. These shortcomings pertain mainly to inadequate manpower, financial resources, implements and machinery required for effectively carrying out various activities for MSWM. Various adopted treatment technologies for MSW are critically reviewed, along with their advantages and limitations. The study is concluded with a few fruitful suggestions, which may be beneficial to encourage the competent authorities/researchers to work towards further improvement of the present system.

Keywords

Municipal Solid Waste, Waste Characterization, Organic Matter.

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P. Meena Sundari ¹, K. Senthamil Selvan ¹, T. Meenambal ²

Affiliations
1 Department of Chemistry, Jansons Institute of Technology, Coimbatore-641 659, Tamil Nadu, IN
2 Department of Civil Engineering, Government College of Technology, Coimbatore, Tamil Nadu, IN

Abstract

The main objective of the study is focused on water quality assessment of various surface water bodies in the Coimbatore city during winter (January 2011) and summer (April 2011). About 75% of the population in the area selected depends on the lake water for domestic purposes, agriculture and industrial purposes. Water samples were collected from four lakes in and around Coimbatore having the same source. The physical and chemical parameters like pH, turbidity, total dissolved solids, electrical conductivity, hardness, concentration of calcium, magnesium, iron, free ammonia, nitrate, nitrite, chloride, fluoride, sulphate and phosphate were analysed and compared with standard techniques. The data were analysed by comparing the values with BIS standards. The studies revealed that water in all the four surface water bodies are to be pre-treated suitably and could be employed for drinking, agriculture and industrial purposes.

Keywords

Water Quality, Lakes, Surface Water Bodies, Coimbatore City.

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L. Yeshodha ¹, T. Meenambal ², H. N. Rajakumara ³

Affiliations
1 Department of Civil Engineering, Adhiyamaan College of Engineering, Hosur, IN
2 Department of Civil Engineering, Govt. College of Technology, Coimbatore, T. N., IN
3 Department of Civil Engineering, Adhiyamaan College of Engineering, Hosur, Tamil Nadu, IN

Abstract

Groundwater abstraction is increasing day by day due to its increasing demand for various uses. Hosur Union of Krishnagiri district completely depends on groundwater for drinking purpose, since the surface water from Penniyar river is very limited. In the present study the assessment of groundwater quantity of this region is taken up, to ascertain the safe yield. The study reveals that the magnitude of annual rainfall and groundwater potential has a decreasing trend. The discharge rate is more than the recharge rate, leading to depletion of the groundwater level. The critical drawdown and safe yield have also been determined.

Keywords

Groundwater, Safe Yield, Hosur Union, Water Level Fluctuation.

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L. Yeshodha ¹, T. Meenambal ², H. N. Rajakumara ¹, S. Arunachalam ¹

Affiliations
1 Department of Civil Engineering, Adhiyamaan College of Engineering, Hosur-635 109, T.N., IN
2 Department of Civil Engineering, Government College of Technology, Coimbatore, T.N., IN

Abstract

This paper describes the study of groundwater fluctuation in the study area using remote sensing and GIS technique. In this study, Hosur Union of Krishnagiri district, Tamil Nadu, was selected as the study area. The base map of the study area was prepared by using Survey of India Toposheet at a scale of 1:50000. The groundwater fluctuations were studied for varying rainfall intensity. The analysis was carried out using spatial interpolation technique and Thiessen polygon method. For the analysis by spatial interpolation technique, the water level fluctuations for every 4 years interval were considered. In this technique, spline method was used to create the continuous surface for groundwater data. This method considers the distance between both unknown points and known points and measures the spatial correlations between two points so that the weights can change according to the spatial arrangements of samples. In Thiessen polygon method, Voronoi polygons were created so that every location within a polygon is closer to the sample point in that polygon than any other sample point. The Voronoi mapping tool provides a number of methods for assigning or calculating values to polygons. The results by both the methods indicated that the overall groundwater potential is low in the study area.

Keywords

Groundwater, Geospatial Modelling, Vornonoi Maps, Remote Sensing, Geographical Information System (GIS).

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R. Praba Rajathi ¹, K. Ashok Kumar ¹, T. Meenambal ¹

Affiliations
1 Department of Civil Engineering, Govt. College of Technology, Coimbatore-641 013, T.N., IN

Abstract

A study was performed on hybrid up-flow anaerobic sludge blanket reactor to identify the start-up time and optimum HRT required for treatment of pulp and paper mill wastewater. Initially, the reactor was loaded at an OLR of 0.117 kg COD/m³.hr and HRT of 24h. Loading rates were increased by reducing HRT 24, 20, 16, 14, 12, 10, 8, 6h, which corresponds to the OLR of 0.117, 0.141, 0.175, 0.201, 0.233, 0.294, 0.348, 0.458 kg COD/m³.h. An optimum HRT of 8 h, HUASB reactor shows COD and TSS removal efficiency of 80% and 85% respectively. When HRT was reduced beyond 8h, lower COD removal efficiency of 71% and TSS removal efficiency of 70% were observed. Finally, the reactor took 120 days for complete start-up. The granule formation was observed inside the reactor by drawing the sample along the port, which shows sizes of 1-2 mm.

Keywords

Hybrid UASB Reactor, Hydraulic Retentiion Time, Organic Loading Rate, Pulp and Paper, Mill Effluent, Start-Up Performance.

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Selvakumar Madhavan ¹, T. Meenambal ¹

Affiliations
1 Department of Civil Engineering, Government College of Technology, Coimbatore-641 013, T.N., IN

Abstract

Geographical Information System (GIS) enables us to integrate and analyse a number of environmental data from different sources to model the overall impact of air pollutants on environment. The objective of this paper is to design an air quality management system. Air quality data were collected from 25 stations in and around Coimbatore city. In this paper a number of spatial and statistical analysis were carried out. Spatial analysis such as overlay, buffering and zoning were performed to provide an environmental alarming system. Among the various environmental standards defined in the world, in this work AQI (air quality index) standard is used. Considering the standards used, good, moderate, unhealthy, very unhealthy and hazardous places were determined. Maps showing the spatial dispersion of TSPM (total suspended particulate matter) and RPM (respirable particulate matter) were prepared. It has been found that in some areas the levels of suspended particulate matter is higher than the prescribed limit of 140 μg/m3 and respirable particulate matter of 60 μg/m³. Based on the GIS output the suggestions have been made to improve better living condition in Coimbatore.

Keywords

Particulate Air Pollution, Vehicular Emission, Coimbatore City, Air Quality Index, GIS.

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N. Lakshminarasimaiah ¹, T. Meenambal ², Lakshmi Priya Thyagarajan ³, N. Ramesh ⁴

Affiliations
1 Department of Civil Engineering, Adhiyamaan College of Engineering, Hosur-635 109, T.N., IN
2 Department of Civil Engineering, Government College of Technology, Coimbatore-641 013, T.N., IN
3 Government College of Technology, Anna University, Coimbatore, T.N., IN
4 Department of Civil Engineering, K.S.R College of Technology, Tiruchengode, T.N., IN

Abstract

Solid waste can be disposed off either by diluting or by making it into useful manure. Since most of the land, water and atmosphere have been polluted largely, the only way to prevent pollution is to make the waste into a useful product. The present study investigates feasibility of blending the fruit waste (mango waste) with poultry waste and cow dung to produce a value added compost. Mango waste usually creates nuisance when compared to other fruit and vegetable waste as it gives foul smell. To achieve good composting mango waste was blended with poultry waste and cow dung at six different weight proportions. Chemical properties of compost like pH, nitrogen, carbon, phosphorus and potassium were observed at different periods, i.e., on the days 1, 21 and 35. Finally, the carbon to nitrogen ratio was compared with all the five samples to identify the best compost. The samples with ratio 1:1:1 and 2:1:1 without mango seeds were considered to be more reliable and efficient to be used as compost.

Keywords

Composting, Mango Waste, Poultry Waste, Cow Dung, Aerobic Decomposition.

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L. Yeshodha ¹, T. Meenambal ², H. N. Rajakumara ¹

Affiliations
1 Department of Civil Engineering, Adhiyamann College of Engineering, Hosur-635 109, T.N., IN
2 Department of Civil Engineering, Government College of Technology, Coimbatore-641 013, T.N., IN

Abstract

The aim of the present study is to analyze physico-chemical parameters of groundwater. In this study, the Hosur block of Krishnagiri district has been selected as study area. The study area has categorized into four zones namely, agricultural, residential, industrial and institutional and five water samples were collected from each zone. The results of analysis were compared with, ISI, ICMR and WHO drinking water standards. The results show that the pH value, turbidity, TDS, fluoride and magnesium were within permissible limits in most of the samples. Calcium was found to be exceeding the permissible limits in many samples. Chlorides and iron were less than the permissible limits. Therefore, it can be concluded that the groundwater was not much contaminated and can be used for domestic purpose.

Keywords

Groundwater Quality, Water Standards, Permissible Limits, Hosur Block.

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N. Ramesh ¹, T. Meenambal ², K. Murugan ³

Affiliations
1 Department of Civil Engineering, K. S. Rangasamy College of Technology, Tiruchengode-637 215, Tamil Nadu, IN
2 Department of Civil Engineering, Govt. College of Technology, Coimbatore-614 013, Tamil Nadu, IN
3 Department of Microbiology, K.S.R. College of Arts & Science, Tiruchengode- 637 215, T. N., IN

Abstract

The present study deals the sources, treatment and strategies for future management of municipal solid waste (MSW) in class I city Erode, Tamilnadu, India, which includes collection, segregation, transportation, treatment and disposal. The study also analysed and reported the existing waste treatment methods, which revealed the necessity for improvement and based on that suggested a suitable technology to improve the system thereby minimizing the associated environmental damage. Ground water samples were also collected in and around the solid waste dumping yard and analysed for their physicochemical characteristics to ascertain the extent of groundwater pollution through leachate. The results revealed that concentration of most of the critical parameters (like hardness, BOD, COD, zinc, iron, etc.) exceeded the permissible limits, which requires the improvement of currently employed solid waste management system. The existing solid waste management practices such as open dumping and vermicomposting techniques are not only inefficient but also inadequate enough to manage huge amount of wastes generated daily. Hence, integrated solid waste management system comprising biomethanation, sanitary landfill, etc. is adopted.

Keywords

Municipal Solid Waste, Biomethanation, Leachate, Groundwater, Biodegradable Waste.

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R. Rajakumar ¹, T. Meenambal ¹

Affiliations
1 Department of Civil Engineering, Govt. College of Technology, Coimbatore-641 013, T.N., IN

Abstract

A study was performed on anaerobic filter reactor to identify the startup time and optimum HRT required for treatment of poultry slaughter house wastewater. Initially, the reactor was loaded at an OLR of 0.77 gCOD/L/day and HRT of 36 h. Loading rates were increased by reducing HRT to 24, 16, 12, 10 and 8 h, which corresponds to the OLR of 1.15, 1.74, 2.27, 2.88, 3.43 gCOD/L/day. At an optimum HRT of 12 h, AF reactor shows TCOD and SCOD removal efficiencies of 69.5% and 77% respectively. Lower COD removal efficiency of 66% was observed when the HRT was reduced beyond 12 h. The SS removal efficiency was 76 %. Finally the reactor took 144 days for complete start-up. The granule size of 1-2 mm and settling velocities of granules of 0.5 to 0.83 m/min were observed in the reactor.

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S. Senthilkumar ¹, T. Meenambal ²

Affiliations
1 Deptt. of Civil Engineering, K. S. Rangasamy College of Technology, Tiruchengode-637 209, T.N., IN
2 Deptt. of Civil Engineering, Government College of Technology, Coimbatore-641 013, T.N., IN

Abstract

Assessment of physico-chemical parameters of groundwater were carried out in a radius of three km from the SIPCOT industrial area of Perundurai. Water samples were collected from different villages and analysed for various water quality parameters like pH, turbidity, colour, odour, electrical conductivity, total dissolved solids, total hardness, calcium, magnesium, sodium, potassium, iron, nitrate, chloride, fluoride and sulphate. The study indicates that groundwaters near the SIPCOT region are not fit for human consumption with regard to many parameters.

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R. Venkatasubramani ¹, T. Meenambal ²

Affiliations
1 Department of Civil Engineering, V.L.B. Janakiammal College of Engineering and Technology, Coimbatore-641 042, T. N, IN
2 Department of Civil Engineering, Government College of Technology, Coimbatore-641 013, T.N, IN

Abstract

A detailed study on water quality was conducted by collecting samples from 20 bore wells of Pollachi taluk, Coimbatore district. A correlation analysis has been carried out among the various parameters. The usefulness of this approach has been demonstrated to predict the quality of ground water. Significant linear relationships among some water quality parameters have been obtained which can be used for rapid monitoring of water quality parameters.

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Lakshmi Priya Thyagarajan ¹, T. Meenambal ¹, L. Mangaleshwaran ¹, N. Lakshminarasimaiah ², N. Ramesh ³

Affiliations
1 Department of Civil Engineering, Environmental Engineering Div., Government College of Technology, Coimbatore-641 013, T.N., IN
2 Adhiyamaan College of Engineering, Hosur, T.N., IN
3 K. S. Rangasamy College of Technology, Tiruchengode, T.N., IN

Abstract

Studies were conducted to evaluate the feasibility of bioconversion of pulp and paper industry secondary treatment sludge with sawdust under aerobic conditions. The composting of the waste was carried out for a period of 90 days by mixing pulp and paper industry sludge (PS) with sawdust (SD) in the ratio of 3:1 and inoculating treatment 1 (T₁) with only cow dung whereas inoculating the treatment 2 (T₂) with cow dung and effective microorganisms (EM). The composting process showed satisfactory results with the cow dung and effective microorganism inoculum, i.e., Treatment 2 (T₂). The different chemical parameters like pH, EC, temperature and C:N ratio were analysed during the composting period. The C:N ratio showed a gradual decrease from 36.12 to 21.02 and 38.30 to 17.63 for T₁ and T₂ respectively on the 90th day of composting. The pH varied from 6.5 to 7.3 and from 6.8 to 7.6 in T₁ and T₂ respectively indicating a good compost quality. The EC values decreased gradually from 2.3 μmhos/cm and reached the value 1.2 μmhos/cm in both the treatments. The nutrient values like NPK were almost equal in both the treatments i.e. Though the nutrients levels were equal, the Treatment 2 (T₂) reached the compost stability at the 90th day whereas the Treatment 1 has not reached the stability or maturity at the 90th day, which is indicated by the C:N ratio. Therefore, it can be concluded that the pulp and paper industry sludge (PS) can be successfully converted into value added compost in the period of 90 days by cocomposting with sawdust (SD) in the ratio of 3:1 and by mixing with cowdung (CD) + effective microorganisms (EM) as inoculum.

Keywords

Waste Management, Co-Composting, C:N Ratio, Bio-Compost, Recycling.

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R. Venkatasubramani ¹, T. Meenambal ²

Affiliations
1 Department of Civil Engineering, VLB Janakiammal College of Engineering and Technology, Coimbatore-641 042, T. N., IN
2 Department of Civil Engineering, Government College of Technology, Coimbatore-641 013, T.N., IN

Abstract

Studies were conducted in the year 2002 and 2003, to know the quality of Borewell waters of five stations of Mettupalayam Taluk, Coimbatore district to assess their suitability for drinking and irrigation. The data were analysed with reference to WHO standards, and it was found that the physico-chemical parameters are within the maximum permissible limits. The study area also reveals that ground water of the area is dominated by magnesium and sodium with chloride.

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M. Ranjit Kumar ¹, T. Meenambal ¹, V. Kumar ²

Affiliations
1 Department of Civil Engineering, Government College of Technology, Coimbatore - 641013, Tamil Nadu, IN
2 Department of Agricultural Engineering, Agricultural College and Research Institute, Madurai - 625104, Tamil Nadu, IN

Abstract

Objective: Land use changes, driven by increase in population, and expansion of commercial interest, are happening in all parts of the world. Reductions in forest area were reported to have resulted in hydrologic changes and consequential disasters. Paired catchment studies were conducted in many parts of the world to assess the effects of changes in forest area on watershed hydrology, but the results from those studies were grounded to the locations of the study and could not be generalized and transferred to other locations. Such studies took very long time, and huge cost, despite many uncontrolled parameters between the catchments. Methods: Conceptual models have been recommended to develop scenarios for changes in land use. A newly developed Watershed Processes Simulation (WAPROS) model has been used for simulating scenarios for land use changes. The study design included: partial conversion of 0, 20, 40 and 60% of agriculture area to impervious area; 0, 20, 40 and 60% of forest area to agriculture; 0, 20, 40 and 60% of forest area to fallow; and complete conversion to forest, and to agriculture area. The reduction and expansion of forest area could be considered as equivalent to deforestation, and afforestation experiments. Findings: The capability of WAPROS model to generate all elemental processes was useful to interpret and link the causes and effects of changes. The scenario results showed: +60% change from forest to impervious area caused -100%, -28.5% and +4.6% changes in overland flow, baseflow and channel flow; +60% change from forest to agriculture caused +6%, -3.9%, and +7.8% changes in infiltration, peak flow and minimum flow. Comparison of 100% conversion to forest, and to agriculture showed higher channel flow and peak flow for full forest, and higher infiltration and evapotranspiration for full agriculture area. Applications/Improvements: The results supported studies that rejected the sponge theory attributed to forests.

Keywords

Agriculture, Forest, Impervious Area, Land Use Changes, Modeling, Scenarios

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M. Ranjit Kumar ¹, T. Meenambal ¹, V. Kumar ²

Affiliations
1 Department of Civil Engineering, GCT, Coimbatore 641 013, IN
2 Department of Agricultural Engineering, AC&RI, Madurai 625 104, IN

Abstract

Macropore flow carries water from the soil surface to deeper profile or groundwater, bypassing the intermediate soil profile. The phenomenon is ubiquitous and not rare. A theoretical framework of this flow has not been perfected so far, but ignoring this process may lead to incomplete conceptualization of soil-water flow. The macropore flow has been modelled based on observed data on morphometry, macropore size distribution and fractal dimensions of soil voids and stain patterns, and incorporated in the Watershed Processes Simulation (WAPROS) model. The performance of WAPROS model was evaluated to be good (NSE - hourly; daily = 0.8578; 0.9020), when applied to a real watershed. The sensitivity of macropore flow submodel showed that the adjustment factor was linearly related to macropore flow. Simulations were performed for five types of soil, namely sandy loam, sandy clay loam, sandy clay, clay loam and silty clay loam (A, B, C, D and E respectively). The values of macroporosity factors and fractal dimensions generated for the five types of soil have been presented. The model generated data for A, B, C, D and E soil types were: the number of macropores: 379, 3074, 3412, 153 and 0; the macropore flow (mm): 1.5121, 9.3667, 15.1728, 4.4055 and 0; the average pore flow (mm/pore): 0.0040, 0.0030, 0.0044, 0.0287 and 0; and the macropore flow to base flow ratio: 0.0055, 0.0474, 0.1908, 0.2759 and 0. The modelling methodology gives encouraging results. The model can be updated as and when better equations are made available.

Keywords

Groundwater, Hydrologic Simulation, Macropore Flow Model, Sensitivity, Soil Types.

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M. Ranjit Kumar ¹, T. Meenambal ¹, V. Kumar ²

Affiliations
1 Department of Civil Engineering, Govt. College of Technology, Coimbatore-641013, Tamil Nadu, IN
2 Department of Agricultural Engineering, Agricultural College & Research Institute, Madurai-625104, Tamil Nadu, IN

Abstract

In this paper a unified framework is proposed to dovetail water balance model into a hydrologic simulation model. The additive and depletive nature of process operations, including the requirement for feedback and retraction, are discussed. The need to breakdown lumped processes into constituent elemental processes for water balance is discussed. The development of storage-process interaction matrix and its convergence towards water balance model are presented. The formulation of WAPROS model and its capability to generate storage-based water balance, process-based water balance, storage-level closure error, model-level closure error and water balance ratios, besides other hydrologic processes are outlined. The distinctions between model error and simulation error and the effects of interactions between them are also highlighted. A hierarchy of errors ‘simulation error-model error-storage closure error’ is proposed for error handling in simulation modelling. In this paper, theoretical development of unified framework is explained.

Keywords

Water Balance Model, Hydrologic Simulation, Model Closure, Closure Error, Model Error, Simulation Error, Hierarchy of Errors, Water Balance Ratios.

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