eChapters

Abstract

A study on the Subsurface groundwater discharge (SGD) in the coastal Cuddalore region of south east India has been carried out. Measurement of surface water Radon, Water level, Electrical Conductivity (EC) and pH for a total of twenty four hours, by hourly interval the measurement has been calculated and promote correlated with tidal values calculated by WX Tide 32 software. The SGD measurements were made by using a modified seepage meter. The study reveals a match with water level variation and tide with minor variation due to influx of surface water. Saline discharges, fresh groundwater discharges and surface water mixing processes were identified along the coast. Lower SGD (37.24 – 79.16 cm/day) were observed during fresh groundwater discharge.

    1.    Salt affected soils;
    2.    Classification of salt affected soils; 
    3.    Formation of salt affected soils; 

Alkali soil
 
Alkali soils are those that contain measurable amounts of soluble salts mostly as carbonates and bicarbonates of sodium. 

Definitions of IPNM 
Concept of IPNM 
Main objectives of INM 
Components of IPNM

Methods of soil fertility evaluation          
    I.    Nutrient deficiency symptoms on plants  
    II.    Plant analysis
    III.    Biological tests   
    IV.    Soil testing
    V.    Spectral sensing for site specific evaluation

Soil fertility evaluation is conducted for providing an adequate supply of essential plant nutriens to ensure optimum plant productivity, while maximising economic benefits and minimising environmental degradation.
 
Mathematical modelling of nutrient application

The significance of an essential plant nutrient was contained in the Liebig’s law of minimum.

Abstract

A study on colloids in groundwater and its relationship with the geochemical parameters is reasonably essential because of its facilitating nature to transport radionuclides in groundwater. Colloid sampling has been carried out in the coastal aquifers of southeast coast of India. Two different bore wells were selected based on the distance from the coast to collect groundwater samples. On the basis of the result achieved from this study, a reliable representation is emerging. The values of pH and EC are governed by the different size fraction of colloids. In this study, the relation between different size fractions of groundwater colloids and its pH, TDS and EC were carried out. These parameters were analyzed in the lab and its influence with four fractions of colloid like 1.2, 0.8, 0.45 and 0.22 µm have been discovered by smooth scatter plot. The accumulation of particles weighting by normal weighing instrument. There is an higher accumulation of particles found in Kalpakkam than Anupuram in all the size fractions. For separation of particles high frequency pressure was used by ultrasonic cleaner had been carried out. This method is very simple and more reasonable than any other methods.

Abstract

In Gadilam river basin, groundwater is found in both hard rock and sedimentary terrain and is the most important source of rural/urban drinking water supply. Gadilam river basin has gained its importance due to the presence of Neyveli Lignite open cast mine (NLC), group of industrial estate (SIPCOT), extensive depressurization of Cuddalore aquifer and boreholes of New Veeranam Scheme (NVS) in the downstream of the basin. A total of 178 water samples were collected in four different seasons at various lithologies. The collected samples were analyzed for various physico-chemical parameters using standard procedures. Geochemical indicators of groundwater were used to identify the chemical processes that control hydrogeochemsitry. Interpretation of hydrogeochemical data suggests that leaching of ions followed by weathering and anthropogenic impact controls the chemistry of the groundwater. Isotopic study reveals that recharge from meteoric source in sedimentary terrain and rock water interaction with significant evaporation prevails in hard rock region. This thorough understanding helps us to make judicial usage and to maintain the quality of this commodity.

Abstract

The development and management of fresh groundwater resources in coastal aquifers are seriously constrained by the impact of seawater intrusion. The coastal aquifers are fragile and this situation becomes more intense like that of the coastal Cuddalore region. The geochemical signature of groundwater of Cuddalore coast was studied for Pre Monsoon, Southwest, North east and Post Monsoon seasons by collecting total of 64 groundwater samples in each season. The collected samples from were analysed for physical parameters, such as electrical conductivity (EC), pH and major ion concentrations, such as Ca, Mg, Na, K, Cl, HCO₃, PO₄ and SO₄. Interpretation of analytical data shows the predominance of  Na–Cl type   in PRM and Ca- Mg-Cl type  is the dominant facies during POM. The Chaddas evaluation diagram shows that the hydrogeochemical evaluation plot for PRM samples fall in  Na-Cl type. The ratios of Na/Cl and Cl/HCO₃ is also enumerated the fact that the most of the samples from PRM and few samples from other seasons also indicates dominance of salt water intrusion.

Abstract

Aquifers are usually composed of permeable layers that can ways a considerable amount of groundwater. Usually, aquifer units are correlated through the concept of lithostratigraphy. For low-permeable aquifers, it is difficult to define the spatial distribution of hydrogeological units, and this study attempts to use geochemical methods to identify the groundwater flow paths in an area of Southeast coast of Tamil Nadu, India. Multiple geochemical analyses, including groundwater chemistry; stable isotopic compositions of d¹⁸O and 8D contents were performed.  Spatial distribution of d¹⁸O, dD, Cl-/HCO-₃ show that northeastern part of the study area seriously affected by seawater intrusion. The highly permeable aquifers at the east coastal region are characterized by high hydraulic conductivity as compared with other regions of the study area. Hydrogeochemical characteristics based on bivariate diagrams of major and minor ions show that changes in the chemical composition of groundwater are mainly controlled by the salinization process followed by cation-exchange reactions.

Fertilizer

Fertilizers are defined as materials having definite chemical composition with a high analytical value that supply essential plant nutrients in available form. They are usually manufactured by industries and sold with a trade name. They are commonly synthetic in nature and also called as chemical fertilizers/inorganic fertilizers/commercial fertilizers other than lime and gypsum. Most of the chemical fertilizers are inorganic in nature.

Methods of fertilizer application

Two major methods are used to apply fertilizers  
I) Application of fertilizers in solid form 
II) Application of fertilizers in liquid forms

Abstract

Dissolved Organic Carbon (DOC) consisting of water soluble organic molecules and by products of organic decomposition and chemical degradation processes, constitutes a critical link in carbon and nutrient cycles. The quality, or chemical and physical character, of DOC affects the degree to which it is transformed by biological and chemical processes. The significance of DOC was studied in layered coastal aquifers of the Pondicherry region during four different seasons. Pondicherry region has varied geological set up ranging from Cretaceous to Recent formations. A total of 52 groundwater samples were collected from various aquifers like Alluvium, Tertiary(Upper Cuddalore, Lower Cuddalore) and Cretaceous for two different seasons of pre- monsoon(PRM), and post-monsoon (POM). The samples were analyzed for major ions and DOC. The range of DOC in the study area is 0-14 mg/l. Very high DOC concentrations were measured during PRM in the samples from Alluvium and Lower Cuddalore Formation. The samples of these formations were compared with pH, Ionic strength, log pCO₂ and carbonate minerals concentration. The alluvial aquifer shows that pH governed dissolution along the coastal tracts and in Upper Cuddalore formation it’s based on interaction between aquifer matrix and groundwater.

Abstract

Groundwater is most favored as a source of drinking water in all over world. It is often thought to be cleaner and easier to treat when compared with surface water and as a result, many wells have been sunk. Uranium and other radionuclides in water can lead to health problems if present in higher concentrations. In order to study the behavior and to understand the influence of lithology in groundwater of Madurai district, a study was conducted by collecting a total of 216 samples of different seasons (Premonsoon, South west monsoon, Northeast monsoon and Post monsoon) with respect to lithology and the number of samples was depending upon their spatial coverage in the study area. The groundwater samples were analysed for U, Ca²⁺, Mg²⁺, Na⁺, K⁺, HCO₃^-, Cl^-, SO₄^2-, PO₄^3-, NO₃^-, F^-, H₄SiO₄, pH, EC, TDS. It was identified that the higher concentration of Uranium (156 ppb) were noted in the northern part of the study area. They are chiefly restricted to the Granitic terrain and nearby Charnockitic regions. The weathering process induces the release of higher U ions from the granitic terrain and the evaporated recharge water from the tank /reservoir  also induces the release of U ions from the rock matrix, it may also be due to fertilizer enriched agricultural return flows. The key source for all these processes and hydrogeochemical processes is identified to be lithology which inturn controls all the other processes in the study area.

Abstract

Amongst all types of major land-use change, extending irrigated agriculture using a surface-water source has the greatest influence on groundwater – both significantly increasing recharge and changing water quality as excess irrigation water infiltrates into shallow aquifers. Hence, in order to understand the impact of the landuse on the groundwater system the study has been aimed to understand the process by adopting geophysical, geochemical and microbial analysis of groundwater samples. The study has been conducted in Chidambaram taluk, with a total area of 92.51Sq.km. A total of 39 groundwater samples were collected for the analysis of major cation and anion along with the microbial analysis, like Total Coliform, Total Viable Counts, Fecal coliforms, Vibrio cholera and Total Streptococci. The geochemical studies reveal that there is no correlation between these parameters and the microbial population. The migration of the water from the elevated regions (urban region) is witnessed and the concentration of the microbial population is higher in these regions except in the southern region which has impermeable clay and this arrest the movement of water.

Toxic elements like Cadmium (Cd), Fluoride (F), heavy metals, radioactive metals are associated with mainly rock phosphates, other organic wastes like sewage sludge and pollutants. Their chemistry is similar to plant nutrients and replace them in their physiology leading to reduced uptake of nutrients, productivity and contaminated food chain.

Dragon fruit, commonly known as pitaya/pitahya (Hylocereus sp.) is a  climbing perennial cacti belonging to the Cactaceae family and the subfamily Cactoidea of the tribe Cactea (Raveh et al., 1993). It is a perennial climbing cactus plant native to tropical areas of North, Central and South America. Main countries growing dragon fruit are Vietnam, Colombia, Mexico, Costa Rica, Nicaragua, Thailand and Taiwan. Cultivation also occurs in Australia, Israel and Reunion Island. The European Union and Asia, especially China are the largest import markets of dragon fruits (Vinas et al., 2012).

Abstract

Under Ministry of Earth Sciences, India Meteorological Department has launched District level Agro-meteorological Advisory Services in June 2008. The agro-advisory bulletins containing the forecast on rainfall cloud cover, wind direction and speed aid minimum and maximum temperature with their likely impact on crops are in use twice in a week.

Abstract

Geochemical processes occurring within the groundwater and reactions with aquifer minerals have a profound effect on water quality. Hydrogeochemical composition of groundwater can also be indicative of its origin and history of passage through underground materials which water has been in contact. Assessing groundwater quality and developing strategies to protect aquifers from contamination are necessary aspects for proper planning and designing water resources. Anthropogenic activities like explosion of population, industrial growth, inputs of fertilizer, pesticides, and irrigation has been a crucial factor for determining the quality of groundwater. In this scenario, 43 groundwater samples were collected from the Dindigul district of Tamilnadu, a Hard rock terrain. The samples wereanalyzed for major cations and anions along with heavy metals to derive the different quality parameters and to obtain the pollution indices of different samples. This study focuses to find out the spatial relationship between the analyzed fluoride concentration in groundwater and pollution indices derived from the heavy metal concentration in the groundwater of the study area and their variation with respect to season.

In his classic book ‘The Ascent of Man’, Bronowski has written, “When I was a young man, we all thought that mastery came from man’s domination of his physical environment. Now we have learned that real mastery comes from understanding and moulding the living environment.” Our Biosphere, the living environment that supports us all, has problems and we humans are mainly responsible. We do not live ‘gently’ on the earth. The seven billion of us require air, water, food, energy, housing and amenities and we have developed the earth to provide them and have also created problems. That the problems exist are serious is the bad news. That we are recognizing them and that man has shown ability to organize and grow in ascending order from time to time is the good news.