Agrochemical fertilizers use in tea gardens and their impact on drinking water sources of Sonitpur district, Assam, India.
India is one of the most important tea producing country in the world, where 60% of tea is produced in Assam a state of India. Historically, Assam is the second commercial tea production region after southern China. Southern China and Assam are the only two regions in the world with native tea plants. The variety of Assam tea tea grown in Assam, in India, originally brought there from China about the year 1850.
See also: Tea is called Camellia sinensis Camellia sinensis,
n See green tea. var.assamica . In Assam there are large multinational tea gardens as well as small tea growers established small tea gardens which is like a revolution. For increase production a large number of agrochemicals are use in these gardens . Types and amounts of chemical substances added to agricultural land are rapidly increasing with development of industrial technology. As a result soil and water pollution becomes conspicuous . In these gardens legally or illegally contaminated fertilizers like zinc-oxy sulphate and sub-standard pesticides are used which are banned in the developed countries. The residues of some pesticides can persist in Verb 1. persist in - do something repeatedly and showing no intention to stop; "We continued our research into the cause of the illness"; "The landlord persists in asking us to move"
continue the environment for more than 20 years . The residues of these chemicals are polluting or contaminating the environment, especially the soil and water, entering in to the food chain, causing threat to human health . So this problem is assumed to be more sever in the near future in the state. In the above context, it is urgent to know as to what extent, the physical environment has been polluted or contaminated by the agro-chemicals. So an attempt has been made to determine the present level of pollution status in the district of Sonitpur, Assam, India.
Materials and methods
The district Sonitpur, (second largest district of Assam after Karbi Anglong in area.) which is taken as study area is located in the north east part of Assam. The total area of Sonitpur district Sonitpur is an administrative district in the state of Assam in India. The district headquarters are located at Tezpur. The district has an area of 5324 km² and has a population of 1,677,874 (as of 2001). is 5103 sq. kms. and lies 100 meter above the mean sea level . It is surrounded by Arunachal Pradesh Arunachal Pradesh (är'ənächəl prədĕsh`), state (2001 provisional pop. 1,091,117), 31,438 sq mi (81,424 sq km), NE India, bordered on the north by the Tibet region of China and on the east by Myanmar. The capital is Itanagar. in north, the Brahmaputra river Brahmaputra River
River, Central and South Asia. From its headsprings in the Tibet Autonomous Region of China (as the Yarlung River), it flows across southern Tibet to break through the Himalayas in great gorges (where it is known as the Dihang). and Morigaon, Nagaon, Jorhat and Golaghat districts in south, Darrang district Darrang is an administrative district in the state of Assam in India. The district headquarters are located at Mangaldai. The district occupies an area of 3481 km² and has a population of 1,503,943 (as of 2001).
The main place of attraction in Darrang is Bhairabkund. in the west, Lakhimpur district Lakhimpur is an administrative district in the state of Assam in India. The district headquarters are located at Lakhimpur. The district occupies an area of 2277 km² and has a population of 889,325 (as of 2001). in the east and. Sonitpur district is located north bank of river the
Brahmaputra within 26[degrees]2 and 26[degrees]6 N latitude and 92[degrees]2 and 93[degrees]5 E Longitude . Located between mighty Brahmaputra River and Himalayan foothills of Arunachal Pradesh, the district is largely plain with some hills. Land use in the district is divided primarily among tropical semi evergreen, moist deciduous deciduous /de·cid·u·ous/ (de-sid´u-us) falling off or shed at maturity, as the teeth of the first dentition.
1. , riverain forest, grassland agricultural land and tea garden. The temperature ranges from 7[degrees]C in January to as high as 38[degrees]C in May. Sonitpur District falls in the Sub-Tropical climatic region, and enjoys Monsoon type of climate. Summers are hot and humid, with an average temperature of 29[degrees] C. The annual rainfall in the district is 2393mm. The climatic conditions of this area are very suit for the tea cultivation. It is interesting to note that the Monabari tea estate, the biggest tea garden in Asia is situated in Sonitpur district. According to according to
1. As stated or indicated by; on the authority of: according to historians.
2. In keeping with: according to instructions.
3. the estimate of 2004, in Sonitpur district itself, there are 62 large tea gardens and 207 registered tea gardens covering an area of 497.57 hectares  and based on this a numbers of small tea industries are growing day by day. The location map of Sonitpur district is shown in figure 1.
[FIGURE 1 OMITTED]
Soil samples were taken at the depth of 0-15 cm. from six selected tea gardens by adopting simple random sampling technique by maintaining a distance of about 50 meters between two samples. A "V" shaped cut at random locations was made in each sampling sites and one inch of soil on either side of pit was scraped and collected in polythene pol·y·thene
n. Chiefly British
Variant of polyethylene.
[poly- + (e)th(yl)ene. bags. Quartering technique was adopted to reduce the size of the sample to the required mass and air-dried. The air dried samples is crushed by hand using pestle pestle /pes·tle/ (pes´'l) an implement for pounding drugs in a mortar.
A club-shaped, hand-held tool for grinding or mashing substances in a mortar. and mortar and analyzed for pH, N,P,K and heavy metals heavy metals,
n.pl metallic compounds, such as aluminum, arsenic, cadmium, lead, mercury, and nickel. Exposure to these metals has been linked to immune, kidney, and neurotic disorders. . For water total 60 numbers of samples were collected from different drinking water drinking water
supply of water available to animals for drinking supplied via nipples, in troughs, dams, ponds and larger natural water sources; an insufficient supply leads to dehydration; it can be the source of infection, e.g. leptospirosis, salmonellosis, or of poisoning, e.g. sources of the six small tea gardens of Sonitpur district. The sources of the water samples were shallow hand tube wells (HTW HTW How Things Work
HTW High Temperature Water
HTW Hazardous and Toxic Waste
HTW Harrison Troughton Wunderman
HTW Honky Tonk Woman (song)
HTW Hack the World
HTW Hard Target Weapon
HTW Harmonize the World ~60ft deep, deep tube wells (DTW DTW Dynamic Time Warping
DTW Dance Theatre Workshop (New York, NY)
DTW Depth to Water (denotes depth to water in monitoring wells)
DTW DoDIIS Trusted Workstation
DTW Development Technology Workshop ) like Tara pump (~120ft deep) and mark tube well (~180ft deep), ring well, ponds and drains. Tube wells were operated at least 10 minutes before collection to flash out the stagnant water inside the tube and to get fresh ground water. The water samples were collected in clean 1L Poly propylene propylene /pro·pyl·ene/ (pro´pi-len) a gaseous hydrocarbon, CH3CHdbondCH2.
propylene glycol a colorless viscous liquid used as a humectant and solvent in pharmaceutical preparations. bottles.
pH of the soil and water samples were measured by Pocket pH meter (Merck, India). The content of chloride and phosphorous phos·pho·rous
Of, relating to, or containing phosphorus, especially with a valence of 3 or a valence lower than that of a comparable phosphoric compound. concentration was determined by the method of Richard . Heavy metals concentration in soil and water were determined by Atomic Absorption Spetro-Photometer [10, 11] (AAS; model Perkin Elmer 200, USA) at their respective wave length and slit width. Hydrate hydrate (hī`drāt), chemical compound that contains water. A common hydrate is the familiar blue vitriol, a crystalline form of cupric sulfate. Chemically, it is cupric sulfate pentahydrate, CuSO4·5H2O. Generation-Atomic Absorption Spectrometry Absorption spectrometry
A scientific procedure to determine chemical makeup of samples.
Mentioned in: Herbalism, Traditional Chinese (Hg-AAS) was used for analysis of As in water samples. S[O.sub.4.sup.2-] content present in the water samples were analysed by turbidimetrically at 450 nm using UV-spectrophotometer (SPECORD 40, Analytic Jena, Germany).
Name of the Agro-Chemicals, which were used in the study area
The agro-chemicals mainly artificial fertilizers and pesticides which are used in small tea gardens are survey by questionnaire which is shown in Table-1.
Result and Discussion
Soil pH: The pH values reflect the health status of the soil as to whether it is fit for cultivation or not. Soil pH is a good indicator for possible nutrient problems. Soils in the study area are highly acidic, with pH ranging from 3.48 to 5.5. This is because of constant addition of agrochemicals in the soils This may affect the nutrient uptake of the tea plant. Williams  has mentioned that chemical fertilizer can play a vital role to change pH condition in soil.
Total Nitrogen (N) in Soil: Nitrogen is essential for plant growth and thus causes problems when it is deficient. The ranges of nitrogen in the study area is 165.8 to 584 Kg/ha. The nitrogen contents of soils in the study area are marginal as according to the chemical rating chart . The highly acidic nature of soils of the study area prevents organic matter from breaking down, resulting in an accumulation of organic matter and the tie up of nitrogen, that are held in the organic matter.
Phosphorous(P) Concentration in Soil: Phosphorous(P) is an important element classified as a macronutrient macronutrient /mac·ro·nu·tri·ent/ (-noo´tre-ent) an essential nutrient required in relatively large amounts, such as carbohydrates, fats, proteins, or water; sometimes certain minerals are included, such as calcium, chloride, or sodium. because of the relatively large amounts of P required by plants. The ranges of Phosphorous in the study area from 2.0 to 48.9 Kg/ha. In acid soils, there is a tendency towards low phosphorous levels over time. This phosphorous applications on soil leaches to water bodies, it may cause eutrophication eutrophication (ytrō'fĭkā`shən), aging of a lake by biological enrichment of its water. In a young lake the water is cold and clear, supporting little life. of water, a form of water pollution. The P in the soil comes from phosphate fertilizers.
Potassium(K) Concentration in Soil
Soil potassium (K) is found in three forms; trapped between clay layers (relatively unavailable), adsorbed on the surface of soil colloids (exchangeable), and in the soil solution (available). The soils in the tea gardens of the study area are ranging from 16.6 to 317.6 Kg/ha.
Monitoring levels of soil organic carbon provides a good measure of the fertility of soil. In the study area the soil samples of tea gardens are found to contain 0.40 to 2.66 percent of organic carbon which is actually low contents. Exploitative, environmentally damaging land management practices in the area tend to reduce soil carbon levels.
The water samples are collected from surface, sub-surface and tube well the pH and concentration of different ions and elements like [F.sup.-], [Cl.sup.-], S[O.sub.4.sup.2-] , P[O.sub.4.sup.2-] As, Fe, Mn, Hg, Cd concentration are shown in (table-3&4).
Different parameters of water quality of drinking water sources were shown in the (table 3 & 4). The pH (WHO limit: 6.5- 8.5) is a numerical expression that indicates to which a water is acidic or alkaline and is an operational parameter. High pH levels are undesirable since they may impart a bitter taste to the water. In the present study the variation of pH is 6.0 to 8.8 which is narrow and in general the pH is towards alkaline side.
The [F.sup.-] concentration in the study area is found from 0.01 to 1.51ppm. which is safe limit provided by WHO . Chloride ([Cl.sup.-]) It is one of the major anions found in water and wastewater. The recommended maximum contaminant level Maximum Contaminant Levels are standards that are set by the United States Environmental Protection Agency (EPA) for drinking water quality. A Maximum Contaminant Level (MCL) is the legal threshold limit on the amount of a hazardous substance that is allowed in drinking water under is 250 ppm, since the chloride ion imparts a salty taste to the water. In the study area the range of [Cl.sup.-] ion is 11.2 to 138.5 ppm. The drinking water limit of Sulphate is 250 mg/L. Sulfate sulfate, chemical compound containing the sulfate (SO4) radical. Sulfates are salts or esters of sulfuric acid, H2SO4, formed by replacing one or both of the hydrogens with a metal (e.g., sodium) or a radical (e.g., ammonium or ethyl). (S[O.sub.4.sup.2-]) is distributed in natural waters, if it is above standard limit then aesthetic problems and sulfates laxative effects occurs. In the study area the the range of sulphate is within limit of 5.8 to 101.56ppm. Phosphate(P[O.sub.4.sup.2-]) is typically a limiting plant nutrient in surface waters, the WHO limiting value in drinking water is 0.1ppm, the concentration of phosphate in the study area is 0.030 to 1.380ppm. which is above the permissible limit the high concentration is due to excessive use of phosphate fertilizer in the soil. The range of As in the study area is 0.001ppm to 0.083ppm. which is above the WHO guide line of 0.01ppm , Arsenic is highly toxic highly toxic Occupational medicine adjective Referring to a chemical that 1. Has a median lethal dose–LD50 of ≤ 50 mg/kg when administered orally to 200-300 g albino rats 2. and its prevalence is due to the natural occurrence of this metal and past use of arsenic in pesticides. Arsenic poisoning typically makes people feel tired and depressed and this poisoning is also associated with weight loss, nausea, hair loss, and marked by white lines across the toenails and fingernails. Iron (Fe),the WHO limit in drinking water is 0.3 ppm. The main source of As is DAP and pesticides. Iron is a secondary drinking water standard and primarily regulated because of the aesthetic problems associated with elevated iron concentrations. The range of iron in the study area is from 0.20 to 24.29 ppm. Which is very high to WHO limit this is because of high amount of micronutrients use in the soil. The problem of iron bacteria is result for high amount of iron present in the water. The study revealed that 80% of total water samples had Mn concentration above the permissible limit (0.3 ppm) of WHO standards .The range of Mn in the study area is 0.02 to 4.59 ppm. Manganese is primarily regulated because of the aesthetic problems associated with elevated levels of manganese, i.e., a secondary drinking water standard. Elevated manganese levels can disrupt the nervous system and regeneration of hemoglobin . Mn may come from use of huge amount of super phosphate in soil. Mecury (Hg) the WHO limit is 0.006 ppm, in drinking water. Mercury has been associated with kidney disease Kidney Disease Definition
Kidney disease is a general term for any damage that reduces the functioning of the kidney. Kidney disease is also called renal disease. . In the study area it has been found from trace to 0.095 ppm. Hg may comes to water sources from pesticides. Cadmium (Cd) is very dangerous for human health, the WHO limit for cadmium in drinking water is 0.003ppm. Cadmium poisoning cadmium poisoning Toxicology A condition associated with industrial exposure to cadmium Clinical renal tubule disfunction–aminoaciduria, glucosuria, hyperphosphatemia, hepatic fibrosis, emphysema and COPD, osteomalacia accompanied by bone pain. is associated with kidney disease and hypertension and possibly mutations. The range of Cd in water sources of study area is found from 0.002 to 1.38 ppm. Cd may come to water sources from super phosphate, DAP etc.
The drinking water pollution in the tea garden areas of Sonitpur district, Assam, is significant. As found out from the experimental results, soils in the tea gardens of Sonitpur district generally have properties that make their management somewhat difficult. The long- term deterioration of soil under the tea gardens in the area has led to impoverishment of soil fertility and stabilization of yields, despite increasing application of external inputs such as fertilizers and pesticides. Among various chemical parameters of soil quality pH, available N, P, K and %C are considered to be sensitive environmental parameters and have direct bearing on productivity and fertility of soils. These agrochemicals have direct impact on the drinking water sources in these tea garden areas. From the present study it is observed that these drinking water sources are poorly managed and show sign of heavy metal pollution. This is may be due to use of agrochemicals in the tea gardens in a uncontrolled manner. In the present state, these drinking water sources are not safe for use in the tea garden community and this may lead to poor drinking water quality. The continuous and uncontrolled use of different chemicals in the tea gardens areas of this region may increase the pollution rate which may lead to cause an adverse health effects to the tea garden community. Even in long term use of these chemicals, they may cause cancers of kidney, lung, liver etc. this is why there is an immediate and urgent need for the implementation of a better water quality management policy in corporating the following recommendations.
* The use of pesticides, insecticides and other chemical inorganic fertilizers should be reduced.
* Tube wells and other drinking water sources should be installed in a safety place.
* The organic fertilizers may increase the rate of tea production and reduce the pollution rate of the environment of water, soil and air.
* A proper planning and management can solve the problems
The authors wish to acknowledge the director NERIWALM, Tezpur, Assam for providing laboratory facilities and thankful to Indira Gandhi National Open University The Indira Gandhi National Open University (IGNOU) Hindi: इन्दिरा गांधी राष्ट्रीय मुक्त , New Delhi for financial assistance in the form of MRP (Material Requirements Planning) An information system that determines what assemblies must be built and what materials must be procured in order to build a unit of equipment by a certain date. , No. D/EDNER/7052.
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International Standard Book Number
ISBN International Standard Book Number
ISBN n abbr (= International Standard Book Number) → ISBN m 0521402166.
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Geneva (jənē`və), Fr. Genève, canton (1990 pop. 373,019), 109 sq mi (282 sq km), SW Switzerland, surrounding the southwest tip of the Lake of Geneva. ).
* (1) Joydev Dutta and (2) A.K. Misra
(1) Department of Chemistry, Chaiduar College, Gohpur, Assam. 784 168
* E-mail: email@example.com
(2) Department of Chemistry, Gauhati University, Guwahati, Assam, 781 014
Table 1: Name of major fertilizers used in the tea gardens of sonitpur district, Assam, india. Fertilizer Formula Urea CO[(N[H.sub.2]).sub.2] Ammonium N[H.sub.4]N[O.sub.3] nitrate Ammonium N[H.sub.4]N[O.sub.3]+ nitrate limestone (CaC[O.sub.3]+MgC[O.sub.3]) Super phosphate Ca[([H.sub.2]P[O.sub.4]).sub.2]x[H.sub.2]O (Normal) +CaS[O.sub.4] Super Phosphate Ca(H2PO4)2.x[H.sub.2]O (Triple) Murate of Potash KCL Diammonium [(N[H.sub.4]).sub.2][H.sub.2]P[O.sub.4] Phosphate(DAP) Dolomitic limestone Ca[Co.sub.3]+Mg[Co.sub.3] Gypsum CaS[O.sub.4]2[H.sub.2]O Micronutrients CuS[O.sub.4]x[H.sub.2]O, and others. [Na.sub.2][B.sub.4][O.sub.7]10[H.sub.2] Zn[So.sub.4][H.sub.2]O, (N[H.sub.4])6[Mo.sub.7][O.sub.24].2[H.sub.2]O Mn(N[H.sub.4])P[O.sub.4].[H.sub.2]O Fertilizer Nutrients % of nutrients Urea Nitrogen(N) N-45 Ammonium Nitrogen(N) N-34 nitrate Ammonium N, Ca, Mg N-20,Ca- nitrate limestone 6, Mg-4 Super phosphate [P.sub.2][O.sub.5], Ca,S P-20, Ca- (Normal) 21, S-11. Super Phosphate [P.sub.2][O.sub.5], Ca,S P-46, Ca- (Triple) 14, S-2. Murate of Potash K K-60 Diammonium N, [P.sub.2][O.sub.5] N-18, P- Phosphate(DAP) 46 Dolomitic limestone Ca, Mg Ca- 24to30, Mg-6to12 Gypsum Ca, S Ca-22,S-18 Micronutrients Cu, B, Zn, Cu- and others. Mo, 25to35, Mn etc. B-11,Zn- 61, Mo- 54,Mn-28 Fertilizer Impurities Urea ... Ammonium ... nitrate Ammonium ... nitrate limestone Super phosphate Cd, Fluride (Normal) Compounds, Cr, Mn, Ni, and Zn Super Phosphate Cd, Fluride (Triple) Compounds, Cr, Mn, Ni, and Zn. Murate of Potash ... Diammonium Cd,Cr,Pb,As. Phosphate(DAP) Dolomitic limestone Heavy metals Gypsum Micronutrients Trace as and others. impurities. Table 2: Conc. of soil quality parameters in tea gardens. Gardens Kg/ha. except pH and C name pH N P K (min.-max.) (min.-max.) (min.-max.) (min.-max.) CR 3.48-4.9 260-264.2 2.0-2.1 23.3-25.4 AS 4.83-5.0 492.3-584 3.14-3.18 23.3-26.8 RP 3.48-4.8 169-172.4 2.01-2.28 16.6-22.4 GD 4.33-4.5 498.7-506.1 6.9-7.04 23.3-28.6 SP 4.5-4.9 277.4-312.9 41.2-48.9 310.5-317.6 SG 4.5-5.4 214.6-235.2 21.7-27.7 44.8-95.6 RU 4.5-4.8 230.6-236.3 26.5-29.6 34.0-38.7 DU 4.5-5.12 214.6-219.5 25.2-32.2 60.7-65.5 BB 4.6-5.1 165.8-167.9 32.8-37.8 99.7-105.5 BD 5.0-5.5 289.3-300.2 40.9-45.2 75.2-80.5 Gardens name %C (min.-max.) CR 0.75-0.78 AS 1.75-1.8 RP 0.51-0.65 GD 1.52-1.62 SP 2.04-2.66 SG 0.52-1.23 RU 0.94-0.99 DU 0.40-0.52 BB 0.53-1.32 BD 0.67-0.77 Table 3: Conc. of water quality parameters of pH, [F.sup.-], [Cl.sup.-], S[O.sub.4.sup.2-], P[O.sub.4.sup.2-] in tea gardens. Gardens Conc. of different water quality name parameters in ppm. except pH pH [F.sup.-] [Cl.sup.-] S[O.sub. 4.sup.2-] (min.-max.) (min.-max.) (min.-max.) (min.-max.) CR 6.0-7.0 0.17-0.23 11.2-33.9 5.8-25.8 AS 6.7-6.8 0.25-0.67 48.0-103.2 15.4-36 RP 7.1-7.3 0.89-1.1 25.6-99.12 20.1-55.0 GD 6.2-8.0 0.15-1.25 55.9-121.7 46.0-97.5 SP 7.0-8.2 0.01-0.99 82.9-111.1 35.5-88.5 SG 7.1-8.8 0.57-1.02 77.6-101.2 23.9-75.3 RU 7.4-7.6 0.75-0.89 101.1-175.2 45.57-94.57 DU 7.5-7.7 0.92-1.51 78.8-138.5 79.96-101.56 BB 6.8-7.7 0.77-0.95 55.5-100.2 55.5-58.86 BD 6.5-7.3 0.76-0.88 57.8-98.9 68.6-70.7 WHO 7-8.5 1.5 250 500 Gardens name P[O.sub. 4.sup.2-] (min.-max.) CR 0.045-1.32 AS 0.105-1.10 RP 0.05-0.135 GD 0.075-0.851 SP 0.080-0.125 SG 0.201-1.380 RU 0.180-1.250 DU 0.030-0.101 BB 0.130-0.160 BD 0.080-0.290 WHO ... Table 4: Conc. of water quality parameters As, Fe, Mn, Hg ,Cd in tea gardens. Gradens Conc. Of heavy metals in ppm. name As (min.- Fe (min.- Mn (min.- Hg (min.- max.) max.) max.) max.) CR 0.001-0.033 0.31-0.62 0.12-1.64 Trace--0.012 AS 0.02-0.032 0.90-3.99 0.55-0.94 Trace--0.11 RP 0.005-0.083 1.31-4.20 0.84-2.99 .004--0.12 GD 0.02-0.09 0.65-0.95 0.89-2.01 Trace--0.11 SP 0.03-0.067 0.5-1.01 0.94-1.49 0.002-0.095 SG 0.01-0.04 0.20-5.20 0.21-1.83 Trace--0.08 RU 0.01-0.02 1.85-13.22 0.43-6.49 Trace-0.001 DU 0.031-0.033 1.61-3.71 0.02-0.47 Trace-Trace BB 0.001-0.005 1.40-10.45 0.02-1.26 Trace-0.012 BD 0.011-0.019 22.78-24.29 0.21-4.59 Trace-0.003 WHO ppm. 0.01 0.4 0.001 Gradens name Cd (min.- max.) CR 0.002-0.014 AS 0.005-0.023 RP 0.05-0.135 GD 0.075-0.851 SP 0.08-0.125 SG 0.201-1.38 RU 0.18-1.25 DU 0.03-0.101 BB 0.130-0.160 BD 0.080-0.290 WHO ppm. 0.003