Ecology and Restoration of Lake Budha Pushkar A Threatened Water Body of Ajmer, Rajasthan

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1 Sengupta, M. and Dalwani, R. (Editors) Proceedings of Taal2007: The 12 th World Lake Conference: Ecology and Restoration of Lake Budha Pushkar A Threatened Water Body of Ajmer, Rajasthan K.C. Sharma and C.S.Chouhan Department of Environmental Studie, Maharshi Dayanand Saraswati University, Ajmer Rajasthan India dr.kcsharma@gmail.com ABSTRACT Lake Budha Pushkar, a threatened water body situated in the Pushkar gap of Aravallis was studied for causes of its degradation and possible restoration practices. The historical records indicate that in the beginning of 20 th century (1906), the lake and its catchment area was rich in wildlife where fishing in the water body and poaching was prohibited. The lake had been a main source of water for Railways for the last over 70 years till The study reveals that two major causes of its degradation are high rate of sedimentation through sandfall from nearby sand dunes and agricultural activities at about 1/2 of the peripheral area of water body. Changes in physico-chemical and biological characteristics were observed. The lake is almost converted into land. Agricultural activities has led to high input of N and P fertilizers along with pesticides being used by the farmers. Sediment was analyzed for its use as fertilizers. It has high content of macro (NPK along with OM) and micronutrients like Fe (39.60 ppm), Mn (18.78 ppm ), Cu (2.38 ppm ) and Zn (3.24 ppm ), as maximum values and 3-6 times higher than the soils of the area. Recently in 2006, Jal Chetna Yatra a campaign through public participation was launched for one month. The excavation during the campaign has resulted in increased water retention capacity of the lake to some extent. A positive response of people was also observed for such restoration programmes. Sand dune stabilization through sand binders mainly Crotolaria burhia Lepidigathis trinervis, Leptadenia pyrotechnica and some grasses had been successful in checking the erosion of soil into the water body. Creating shelter-belts and watersheds in the vicinity are other options for restoration. Keywords: Water Quality, Sediment Analysis, Phytoplanktons, Restoration practices, Jal Chetna, Water conservation awareness. INTRODUCTION Lakes and reservoirs in arid and semi arid regions serve as important water resource for inhabitants of the area. The interaction with man with water bodies during the last few decades has been of concern largely due to the rapid population growth which resulted in degradation of water bodies by domestic, industrial sewage, agricultural run-off containing fertilizers and pesticides (Prasad et al. 2002). The fact that wetland values are overlooked has resulted in threat to the kidneys of the landscape (Mitsch and Gosselink 1986). Hydrologic conditions such as amount of precipitation, water loss due to high heat indices and man induced perturbances can modify chemical and physical characteristics such as ph, nutrient availability, soil salinity, degree of substrate anoxia and sediment properties. These changes in physicochemical environment have direct impact on the biotic component of the water body. The ecological parameters of such water bodies may provide clues for understanding the key relations which are relevant for restoration strategies. Restoration requires reconstruction of antecedent physical conditions, chemical adjustment of soil and water; and biological manipulation (Zedler 1996). Conservation measures of inland water bodies in India have been described (Gopal 1994). Besides other restoration practices based on ecological principles, public participation is important for fast recovery of degraded ecosystems. The concern of public is intensified because many areas in the country including the Pushkar Valley are declared as sensitive zones. Therefore, restoration of existing water bodies in the Aravallis needs immediate attention from the government as well as from the stakeholders. The main objective of this study was to determine the current ecological status of the lake Budha Pushkar and to outline suitable measures of its restoration. The impact of public participation was also determined by taking the example of awareness campaign launched in STUDY AREA The lake Budha is situated in the Pushkar gap of Aravallis (Fig. 1) at a distance of 13kms NW to Ajmer ( N Latitude and E Longitude, 502 m msl). It is a holy lake surrounded by

2 sand dunes and agricultural fields. The total capacity of the lake is more than 150 million cubic feet with water spread of 4.5 hectare. The ground water is about 10 feet deep from the surface. The climate is semi arid type. The temperature of this area is high during the summer (May-June) and touches 44 0 C-46 0 C, while it goes down to 5 0 C during winters (December January). The rate of evapo-transpiration is comparatively higher than in the South Eastern region of Rajasthan. The wind speed during the summer is km per hour and leads to sand shifting and sedimentation into the lake. The Lake is surrounded by varying heights of sand dunes. Intensive agriculture, grazing, excavations and other anthropogenic activities are some of the features of catchment area. Budha Pushkar had been the main source of water supply for Railways and its residential colonies till Thus multiple factors pertaining to overexploitation of water and activities in the catchment area along with natural causes of low rainfall (annual average 700 mm), extreme temperatures and sand shifting are responsible for its degradation over the years. Figure1. Location Map of Lake Budha Pushkar 1758

3 MATERIALS AND METHODS Analysis of physico-chemical and biological parameters helps in assessing the status, which is further required for evolving appropriate restoration methods towards conservation and management. For analysis of physico-chemical characteristics of water, samples were collected in each month (10th-15 th day) during the year 2005 and To cover the entire part of the lake and to determine the range of physicochemical parameters, water samples were collected from five sites in the shallow zone at the periphery. The samples were collected in acid washed bottles and in polyethylene bags of two liter capacity. The temperature, ph, electrical conductivity and DO were analyzed immediately after sampling at the site of the lake. Various physico-chemical parameters viz., dissolved oxygen, Ca and Mg-hardness, Total hardness, Total alkalinity, Free CO 2, Chlorides, TS, TDS, TSS, Nitrate, Phosphate, Sodium and Potassium were determined as per the standard methods described in APHA (1992), Trivedi et al. (1998) and Maiti (2001). The analysis of sediment samples along with soils collected from nearby sand dunes/agricultural fields was performed for micronutients like Fe, Mn, Cu and Zn. Surveys of the area were conducted for relevant information and for collection of algal samples. Census data of 2001 were used to identify the level of awareness and keenness among the population of Budha Pushkar area. The Water Awareness programme initiated in May, 2006 was studied at the site and also gathered relevant information from different sources. RESULTS AND DISCUSSION During the past ten years, the total annual rainfall of the Pushkar area is comparatively low, ranging from about mm to mm with some exceptions. The rainfall pattern it slightly changed during the recent years. Comparing with Ajmer, the total rainfall is higher in Pushkar area, though it is 10 km from the Ajmer. This is because of the separation of Pushkar by Nagpahar hillocks of Aravalli ranges. The population of village Kanas, Budha Pushkar is estimated at around 1631 (Census 2001). Unlike other towns population growth of Pushkar has been slow during the last five decades, i.e 5934 in 1951 to in This population growth of the town and its hinterland is largely due to absence of any major economic activity to boost up migration. The literacy of villages is comparatively low (Table 1). Water Quality The maximum and minimum values of physicochemical parameters of water collected from different sites of the lake are shown in Table 2. In general, data on water quality is indicative of polluted water, which leads to eutrophic condition. Extreme seasonal temperature variation is due to differential amount of light incidence over the water surface in different seasons, which is an important factor in arid and semi-arid regions (Vyas 1968; Kumar 1996). Values of some of the physico-chemical parameters are comparatively high. These include TDS ( mg/l), Total Alkalinity (775.0 mg/l), Total Hardness ( mg/l), Calcium Hardness (264.0 mg/l) Total Solids ( mg/l), TSS ( mg/l). The dissolve solids mainly consists of carbonates, chlorides, nitrates, calcium, sodium and potassium. These high values of total solids and TSS and other parameters are significantly high than urban water body of Ajmer (Sharma and Sharma 1992, 1993). The values of total alkalinity also indicate polluted condition of water ( Phillipose 1960). Table1. Demographic Profile of some villages of Budha Pushkar Lake. Hokra Nedliya Kanas Deonagar Household No Total Population Total male Total Female Person Literate Person Illiterate Source: Census (2001) 1759

4 Table 2. Physicochemical characteristics of water of Lake Budha Pushkar S. No. Parameters Site-I Site-II Site-III Site-IV Site-V Min Max Min Max Min Max Min Max Min Max 1 Water Temp. ( 0 C) ph Conductivity ( mmhoscm -1 ) TDS (mg/l) D.O. (mg/l) Total Alkalinity (mg/l) Total Hardness (mg/l) Ca Hardness (mg/l) Mg Hardness (mg/l) Ca++ (mg/l) Mg++(mg/L) Chlorides (mg/l) Total Solids (mg/l) TSS (mg/l) Sodium (mg/l) Potassium (mg/l) Free CO 2 (mg/l) Nitrate (mg/l) Phosphate (mg/l) The maximum values of nitrates and phosphates was 1.53 mg/l and 2.90 mg/l respectively. The standard value of nitrate for inland surface water is 0.1 mg/l (NEERI 1988). This is important parameter in view of its role in increased productivity rate of aquatic ecosystem. Source of nitrate nitrogen to freshwater environment include drainage from the surrounding agricultural areas during rainfall, runoff has been shown to be an important contributor of nitrate nitrogen in reservoir (Sylvester 1961; Sondergaard and Jensen 1979). The phosphate is precipitated with many cations and accumulates in the bottom of the lake. Therefore, it controls the growth of many organisms as well as responsible for accelerating eutrophication of the lake. The standard value of phosphate is 0.2 mg/l for surface inland water. Schindler et al. (1971) concluded from nutrient studies on small lakes that phosphorus is a limiting factor in inland waters. Runoff from the agricultural fields adds P and N into the water body. A similar condition exists in lake Budha Pushkar. DO concentration ranged from 1.60 mg/l to 7.90 mg/l. The recommended dissolved oxygen concentration for healthy and productive water body is 8 mg/l (Wetzel 1973). Variation of oxygen in water depends upon the temperature of water, which influence oxygen solubility (Zutshi and Vass 1978). Free CO 2 was maximum to be mg/ l while minimum value was 4.4 mg/l. Sediment Analysis Sediment samples were analyzed with respect to various nutrients (Table 3). The values of nutrients show wide variations in Organic Matter (0.35% 1.29 %), Nitrogen ( kg/ha 1293 kg/ha), Phosphorus (23.0 kg/ha 44.0 kg/ha) and Potassium (220 kg/ha kg/ha). Sediment with high content of these nutrients may be used as fertilizer for agriculture which is environmentally friendly practice for farmers. Micronutrient analysis of sediment and soil samples from catchment area was also made for Fe, Mn, Cu and Zn (Table 4). Data on micronutrient analysis reveal that the nutrient level in sediments is significantly higher than in the soils of nearby areas. The range of different nutrients are: Fe ( ppm), Mn ( ppm), Cu ( ppm) and Zn ( ppm). The value of Fe in sediment is significantly high i.e. 7 8 times than the soil samples, while value of other micronutrients is 2-4 times higher in sediment than soils of the area. It has been established that micronutrients form an essential component of nutrient 1760

5 capital of the soil and their availability is determined by parent material, organic matter, redox potential, ph, moisture and other biological factors (Fageria et al. 2002). High level of Fe in the sediment palys an important role in determining the solubility of phosphorus, sulphur, trace elements and dissolved organic carbon (Kalff 2003). The amendments of sediment of Budha Puhkar with field soil (sandy soil) has favored the production and yield of some agricultural crops (personal view points of farmers of the area). However, runoff from agricultural fields containing different pesticides and other agrochemicals may be harmful in case these are accumulated in sediments. Phytoplanktons Phytoplanktons are the indictors of water quality. The phytoplankton community of the lake comprised of species like Ankistrodesmus falcatus, Chlorella vulgaris, Cladophora glomerata, Spirogyra inflata, Scenedesmus quadricauda, Synendra ulna, Navicula cryptocephala, Nitzschia palea, Tabelaria flocculosa, Cyclotella sp., Fragilaria sp., Gloeocapsa punctata, Synura sphagnicola, Oscillatoria sp., Microcystis aeruginosa, Lyngbya, Aphanizomenon, Euglena sp., Phacus longicauda etc. Bacillariophyceae or Cyanophyceae is dominant than other classes in different seasons, while members of Euglenophyceae are present in least number (Chouhan and Sharma 2007). Total 36 algal species were identified from lake Budha Pushkar. These are from Chlorophyceae (13), Bacillariophyceae (11), Cyanophyceae (10) and Euglenophyceae (2). This indicates that the lake waters is polluted and leading to eutrophic state, in periods when water is present. Restoration Practices The basic principle of restoration is the protecting the water body from anthropogenic disturbances. This leads to restore the ecological integrity which refers to the condition of an ecosystem particularly the structure and function and interactions with other components. For this purpose, causes of degradation are first identified along with elimination of ongoing stresses wherever possible. A century ago, the lake Budha Pushkar was rich in biological diversity and wildlife. An order of July 18, 1906 passed by the then Assistant Commissioner and District Magistrate Ajmer Mr A.B. Minchin that In view of the sanctity attaching to the Budha Pushkar Lake, shooting, fishing and the destruction of any kind of animal life is strictly prohibited therein or in its immediate vicinity. indicates that the lake once rich in wildlife is now threatened and at the verge of extinction. The main causes of its degradation and possible restoration practices have been tabulated (Table 5). The core elements identified for restoration are shown (Fig.2) which include: Table 3. Physicochemical characteristics of sediment of Budha Pushkar Site-I Site-II Site-III Site-IV Site-V Parameters Min Max Min Max Min Max Min Max Min Max ph Conductivity (m mhos cm -1 ) Org. Matter (%) Total Alkalinity (mg/100 g) Available Nitrogen (kg/ hact.) Available Phosphorus (kg/ hact.) Potassium as K2O (kg/ hact.) Table: 4.. Micronutrient Analysis of sediment of Budha Pushkar Parameters Site-I Site-II Site-III Site-IV Site-V Avg. Fe (ppm) Mn (ppm) Cu (ppm) Zn (ppm)

6 Figure 2. Restoration elements for Lake Budha Pushkar Table 5. Causes of degradation and possible restoration practices for Lake Budha Pushkar Causes of lake degradation Key Elements Restoration practices 1. Climatic stressors 2. Sedimentation 3. Soil Erosion 4. Overexploitation of water 5. Agriculture in Catchment 6. Invasive plant species Low rainfall ( mm) Extremely high temperature (> 45 0C; High heat index and evapotranspiration, wind velocity Sand shifting from mobile dunes; organic matter accumulation over the bed of lake Wind velocity and bank destabilization during rains Exploitation for domestic supply and irrigation Land use patterns and use of agrochemicals Plants like P.chilensis, Lantana camara, Parthenium hysterophorus increase competition for indigenous taxa, release allelochemics 7. Overgrazing Grazing of regenerating species by cattles Developing watersheds and wind barriers. Excavation may reduce water spread and check evapotranspiration. Water retention and storage capacity is increased. Checking sand shifting through suitable barriers. Revegetation of plant species Revegetation of sand binders and checking water runoff through suitable barriers Declared sensitive zone by GOI, Irrigation demand be reduced for some years. Change land-use pattern, reduce water requirement and use of synthetic agrochemicals. Mechanical irradication at early growth stage, used for fuel. Allocation of grazing lands away from catchment areas 8. Religious offerings Offerings of flowers and ashes of dead bodies. Allocate specific site with lake water 1. Stabilization of sand dunes through revegetation reduces soil erosion to a greater extent. The plant species like Crotolaria burhia, Leptadenia pyrotechnica, Borreria stricta, Lepidagathis trinervis, Cenchrus setigerus, C. ciliaris are well adapted to the area and may be used for revegetation. 2. By developing a tree belt of species like Ailenthus excelsa, Acasia Senegal, Prosopis cineraria etc. may check shifting of sand and reduces water loss through reducing the rate of evapotranspiration. 3. The organic rich sediment has high N and P nutrients and may be utilized as fertilizer in agricultural fields. The practice should be repeated periodically till the lake resumes its ecological integrity. 4. Public participation has been successful in desilting of the lake. Awareness campaign may be organized periodically. Recent efforts of creating water conservation awareness campaign named Jal Chetna has been successful. Jal Chetna Campaign In 2006, restoration of lake Budha Pushkar was initiated by Smt Vasundhra Raje, Chief Minister of Rajasthan. She has shown her keen interest in follow up programmes. The restoration effort named Jal Chetna mainly concentrated on de-silting and excavation of the lake to increase its capacity for water retention. It created awareness for conservation of water and about the sanctity of the water body. About 2.60 million cubic feet of sediment was dredged out 1762

7 though Shramdan and Department of NW Railway during the year. The total expenditure in the entire campaign was Rs. 1.5 million provided by different government and non-governmental agencies. The restoration campaign has made awareness in the common man which is evident from collection of Rs million for renovation of Ghats around the lake. The positive impact of excavation through Jal Chetna has been observed with respect to increase in water depth, afforestation of catchment area and volume of the water body (Table 6). This has been a unique experience of restoration involving the public and created much interests in conservation of water resources of the area. The following general principles and measures of restoration are effective for any water body and be considered for Lake Budha Pushkar: Table 6. Effect of recent excavation through Jal Chetna Campaign on lake capacity S.No. Parameter Unit 1 Area of excavation 1.95 ha 2 Depth before excavation m 3 Depth after excavation 3.0 m 4 Volume* before excavation 33,150 m 3 5 Volume after excavation 58,500 m 3 * Volume in cubic metres Multi-disciplinary approach A multi-disciplinary team involving experts from ecology and engineering, government agencies and private organizations is necessary to prepare the restoration plan. Scientific, financial and social aspects may be taken into consideration. Ecological Integrity It is important to ensure the long-term viability of the restored water body by minimizing the needs and human interference at the site. This will further help in maintaining the ecological integrity and self-- sustainability of water body as good condition is more likely to have the ability to adapt to changes. Passive restoration Passive restoration relies mainly on natural processes and it is still necessary to analyze the site's recovery needs and determine whether time and natural processes can meet them. This is done with minimizing the anthropogenic activities in and around the lake. Bioinvasions Many invasive species outcompete natives because they are expert colonizers of disturbed areas and lack natural controls.the lake catchment area is dominated by invasive species such as Lantana camara, Prosopis chilensis, Parthenium hysterophorus. These invasive plant species have suppressed the growth of many indigenous flora which has medicinal values along with their importance in maintaining the ecological integrity of Budha Pushkar. Bioengineering techniques A suitable method of construction combining live plants with dead plants or inorganic materials, to produce living, functioning systems to prevent erosion, control sediment and other pollutants, may be applied for restoration of such water bodies. These techniques would be successful for erosion control and bank stabilization. As a strategy, the lake restoration programme must involves activities to protect, restore, manipulate, and provide for the functions and values emphasizing quality and sustainable usage of water resource (Walters 1986). For a water body like Budha Pushkar, a buffer zone consisting of diverse vegetation along the perimeter of waterbody, preferably an indigenous species which may serve as trap for sediments, nutrients and other pollutants, reducing human impacts by limiting easy access and acting as a barrier to invasion of weeds may be developed. Such zones have been successful as restoration practice for lakes (Stockdale 1991). In general, lakes require a collaborative research involving natural, social and inter-disciplinary study aimed at understanding the various components, such as, monitoring of water quality, socio-economic dependency, biodiversity and other activities as an indispensable tool for formulating long term conservation strategies (Kiran et al. 1999). This needs multidisciplinary-trained professionals in educating the essence of wetland importance, particularly in arid and semi-arid regions, involving the local school, colleges and research institutions. CONCLUSIONS In arid and semi arid regions, lakes are being threatened by multifold pressures like soil erosion, overexploitation of water for irrigation and domestic use, agricultural practices in the catchment area along with natural causes including high temperature, low 1763

8 rainfall and water loss due to higher rate of evaporation. Result revealed that lake Budha Pushkar is alkaline in nature and enriched in nitrate and phosphate and micronutrients contents. Therefore, it is a good option to use the sediments as fertilizers for agricultural fields. The lake is eutrophic and the water quality is poor due to agricultural runoff which includes pesticides and other chemicals. Revegeation of sandy areas in the catchment and developing tree belt around the lake are suitable practices for restoration. This will also leads to increase water recharge in the area. To retain the ecological integrity of the water body, anthropogenic activities must be reduced. Water awareness programmes like Jal Chetna must be continued. REFERENCES APHA. (1992). Standard Methods for the Examination of Water and Waste Water, 18th ed. American Public Health Association, Washington, DC. Chouhan, C. S. and K. C. Sharma. (2007). Limno-biotic status of Religious Lake Budha Pushkar near Ajmer, Rajasthan. Proceedings of National Symposium by DAE-BRNS, Udaipur. Fageria, N.K., V.C. Bligar and R.B. Clark. (2002). Micronutrients in crop production Advances in Agronomy. 77: Gopal, B. (1994). Conservation of Inland waters in India: an overview. Verhandlungen der Internationalen Vereinigung fur Theorestische und Angewandie Limnologie 25: Kalff, Jacob. (2003). Limnology: Inland water ecosystems, Prentice-Hall, Inc.N.J. Kiran, R and T.V. Ramachandra. (1999). Status of wetlands in Bangalore and its conservation aspects. ENVIS Journal of Human Settlements, March 1999: Kumar, A. (1995). Some limnological aspects of the freshwater tropical wetland of Santhal Pargana (Biahar). J. Environ. Pollut. 2: Kumar, A. (1996). The limnological profile of a tropical fish farming pond at Dumka (Santhal Pargana), Bihar. Journal of Ecobiology. 8: Maiti, S.K. (2001). Handbook of Methods in Environmental Studies. Vol 1. Water and Waste Water Analysis. ABD Publishers, Jaipur, India Mitsch, W.J. and I. J. Gosselink. (1986). Wetlands. Van Nostrand Reinhold, New York. National Environmental Engineering Research Institute (NEERI). (1988). Water and Waste water analysis. Nagpur, India: NEER. Philipose, M.T. (1960). Fresh water phytoplankton of inland fisheries. Proc. Symp. Algol. ICAR, New Delhi. Prasad, S.N., T.V. Ramachandra, N. Ahalya, T. Sengupta, Alok Kumar, A.K. Tiwari, V.S.Vijayan and Lalitha Vijayan.. (2002). Conservation of wetlands of India-a review. Tropical Ecology, 43(1): Schindler, D.W., F.A.J.Armstrong, S.K. Holmgren, and G.J. Brunskill. (1971). Eutrophication of lake 227, Experimental lakes area, Northwestern Ontario, by addition of phosphate and nitrate. J. Fish. Res. Bd. Can.28: Sharma K.C. and Renu Sharma. (1992). Algal Diversity in the littoral zones of a polluted shallow lake at Ajmer, Rajasthan. Int. J. of Eco. and Env. Sci.18: Sharma R..and K.C.Sharma. (1993). A note on trophic state of Anasagar lake, Ajmer. Geobios new report 10: Sondergaard, M. and K.S. Jenson. (1979). Physico-chemical environment, phytoplankton biomass and production in oligotrophic, soft water lake Kalgaard, Denmark, Hydrobiologia 63. Stockdale, E. (1991). Freshwater wetlands, urban storm water and non point source pollution control: A literature review & annotated bibliography. Olympia, WA: Washington Department of Ecology. Sylvester, R.O. (1961). Nutrient content of drainage water from forested urban and agricultural areas. Algae and metropolitan Wastes, U.S. Public Health Service, SEC, TR W61-3, Trivedi R.K, P.K. Goel and C.L. Trisal. (1998). Practical methods in Ecology and Environmental Sciences, Enviromedia Publications, Karad, India. Vyas, L.N. (1968). Studies in phytoplankton ecology of Picchola lake, Udaipur. Proc. Symp. Recent. Adv. Trop. Ecol. Pp Walters, C. (1986). Adaptive Management of Renewable Resources. Macmillan, New York. Wetzel, R.G. (1973). Productivity investigation of interconnected marl lakes: The eight lakes of the Oliver and Walters chains, northeastern Indiana. In J. Hrbacek, & M. Straskraba (Eds.), Hydrobiological studies 3 (pp ). Prague, Czech Republic: Academia Publishing House of the Czechoslovak Academy of Sciences. Zedler, J. (1996). Ecological issues in wetland mitigation: An introduction to the forum. Ecological Applications, 6(1): Zutshi, D.P. and K.K. Vass. (1978). Limnological studies of Dal lake II. Chemical features. Indian J. Ecol.5: