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Ecological studies of Anasagar lake with reference to physico-chemical characteristics and pollution have been studied. In this lake different parameters of water indicate the polluted water which directly affect the life cycle and health of different fishes found in the lake.

Therefore, it is imperative to recognize the adverse effects of pollution on aquatic life and take measures to prevent and mitigate its impact. This can be achieved through the implementation of proper waste management practices, the use of eco-friendly products, and the enforcement of environmental regulations. By taking steps to reduce pollution, we can ensure the preservation of aquatic life and the sustainability of our planet's ecosystems.

In India water being spread in a vast area with sea water, costal, estuarine and fresh water, there is a tremendous scope for studies. In limnological studies planktonic life, productivity and physic-chemical studies gained a major thrust to establish the status of water body and quality of water.

Sunil, S K Sharma, M L Ojha, N. Chouhan and L. Jat (2021) studied Primary productivity and plankton diversity of Anasagar lake in relation to fisheries potential.

V.P. Bairwa, B.K.Sharma, S K Sharma, N R Keer and V Kumar (2019) recorded Icthyofaunal diversity of Goverdhan Sagar Lake, Udaipur, Rajasthan.

Dr.B Nakul, Dr. B K Sharma (2017) studied on the biotic and abiotic component of the lake Udai Sagar Ecosystem, Udaipur, Rajasthan

In the Indian state of Rajasthan, the city of Ajmer is home to the man-made lake known as Ana Sagar Lake. It was constructed between 1135 and 1150 AD by Arnoraja (also known as Ana), Prithviraj Chauhan's grandfather, and bears his name. The local population contributed to the construction of the catchments. The lake is 13 kilometres long (8.1 mi). The Daulat Bagh garden was built by the Mughal Emperor Jahangir next to the lake. Five pavilions (known as Baradari) were built by Shah Jahan between the lake and the garden. The lake in Ajmer is the largest and has the most built-up area (5 km2 [1.9 sq mi]). The lake has a maximum depth of 4.4 metres (14 feet) and a storage volume of 4,750,000 m3 (6,210,000 cu yd) Originally, it was a monsoon-fed, perennial, shallow freshwater lake that was built as an adaptation to climate variability (Panday et al., 2013) The samples were analysed chemically with of standard methods(APHA1989,Trivedi &Goel1986),The Fishes species were identified by Taxonomy key(Day’s volume).Fish diseases studied by (V.G.Jhingran)

Table 1 : Physiochemical characteristics of Anasagar lake water

Months	Temp. (oC)	pH	DO (mg/L)	FCO2 (mg/L)	Nitrate (mg/L)	Chloride (mg/L)	Alkalinity (mg/L)
January	18.04	7.58	6.00	4.20	0.10	38.10	112
February	21.05	7.00	5.25	4.00	0.11	48.52	117
March	22.24	7.65	4.50	3.20	0.11	66.59	162
April	26.19	7.65	4.65	3.25	0.12	60.53	192
May	28.00	8.10	5.00	4.00	0.30	68.00	202
June	33.19	8.35	2.50	4.70	0.21	83.50	262
July	29.00	7.05	2.60	4.36	0.39	58.20	242
August	28.49	6.60	3.00	5.25	0.35	52.50	162
September	28.69	5.05	3.10	5.70	0.31	48.50	152
October	27.09	6.30	4.00	5.25	0.26	44.60	132
November	26.00	7.00	4.70	5.00	0.24	41.04	127
December	23.24	7.20	5.30	4.25	0.22	40.54	120

  Table 2 : Disease observed in Fishes

Name of Fishes	Gill disease	Oxygen starvation	Fin rot	White Spot	Dropsy
Labio rohita	**	***	*	***	***
Catia calia	*	**	*	*	**
Mirgal cap	*	**	**	**	**
Tilapia	**	**	*	**	***
Cyprinus carpio	***	***	*	*	***
Hypophthalmichthys molitrix	**	***	**	*	**

*(Rare) **(Common) ***(Abundant)

Factors affecting fishes

Pesticides

Near Anasagar Lake, Pesticides and other toxic chemicals that are used in the home environment, on farms and in industrial manufacturing run off during rainy seasons, these pesticides get accumulated and cause contamination to fishes. These chemicals can cause disease and death in fishes. Lower levels of discharge may result in an accumulation of the pollutants in aquatic organisms. The end results, which may occur long after the pollutants have passed through the environment, include immune suppression, reduced metabolism, and damage to gills and epithelia.

Nutrients

In Anasagar Lake, the Nutrients that run off from farms and are leaked from sewage feed algae in the lake. The algae with increased amounts of nutrients grow at a rapid rate and form what is called red tides. They are called red tides because of the red appearance they give to the foam of the water waves. Red tides release toxins that kill fish.

Sewage Runoff

Pollution runoff into water of Anasagar Lake. Tones of untreated sewage are dumped in water causing pollution.

This increases the amount of nitrates & phosphates. Sewage runoff from farms and human waste can introduce pathogens into the water that can cause diseases in humans and fish.

Fish may be poisoned by a wide range of polluting substances, including, acids, ammonia, phenols, and cresols, compounds of metals, detergents, or cyanides. Many of these substances are released through drains or are accidentally spilled into the lakes.

Trash

Anasagar Lake is a famous holiday spot. Many people come to visit this spot.

Trash, especially plastics, is used by thousands of humans, which is then thrown into the lake.

This causes a lot of death to fish. Plastics take hundreds of years to biodegrade and therefore remain in the water for a long time. Fish can take plastic for food sources and eat them. When ingested, plastic can cause a blockage in the digestive system and kill the fish.

Plastic items get stuck around an animal's mouth making them unable to eat and causing them to starve to death. Plastic items can get stuck around the neck of fish life and cause them to slowly choke to death

Noise Pollution

Noise pollution from boats and drilling near Anasagar Lake causes stress in fish.

Fishes are becoming deaf, failing to reproduce and even dying because of underwater man-made noise pollution.

Underwater noise especially threatens fish with swim bladders because they can explode, sound-sensitive internal structures, causing internal bleeding and even death.

Constructions

As large number of colonies construction projects are in progress in nearby area of Anasagar lake results in the production of silt in the lake. This load of particulates matters cuts down primary productivity of soil and also prevent the reproduction of fish by smothering egg laids on the bottom. Sewage & silt bring about an early ageing of the lake & ponds.

Eutrophication

As one side of the Anasagar Lake is used by washerman's so huge amount of detergents & soap foam too get added. Amount of sulphates, chlorides, etc. increases & these compounds favour the growth of algae producing water algal blooms, which consume most of the oxygen from water & causes toxic effects.

Algal bloom triggering fish-killing "dead zone"

Bottom fish are being killed by a recurring "dead zone" of low-oxygen water that appears to be caused by explosive blooms of tiny plants known as phytoplankton, which die and sink to the bottom. The phytoplankton are eaten by bacteria, which use up the oxygen in the water

Dead zones are caused by agricultural runoff, fueling, and bloom of algae that rot and deplete the oxygen

 Suffocation

Suffocation occurs when the oxygen concentration in the water falls below the level at which fish can survive. A common cause is Eutrophication, which is the artificial stimulation of plant growth by pollution with fertilizers, sewage, or atmospheric fallout. When the excess plant growth decays, it lowers the oxygen concentration.

The discharge of dead organic matter into a watercourse from a sewer or from an industrial operation causing low-oxygen conditions, cause problems by reducing water clarity, making it hard for marine animals to find food and blocking the sunlight needed by sea grasses, which serve as nurseries for many important fish species. Nuisance algal blooms may also cause suffocation. Bloom sank and decomposed, forming an area with almost no oxygen and with lethal levels of hydrogen sulphide killing hundreds of fishes and other aquatic animals.

Acid rain

.Acid rain effects Fishes because when the (acid) rain falls in the pond or the lake, the acid collects in the water becoming stronger and stronger until the fish can't live any longer. Acid rain negatively affects fish by raising the acidity of the water to a level the fish cannot abide and by leaching metals such as aluminium from the soil that can poison fish.

The reduction in food availability can diminish the predatory capabilities of these fish. Pollutants present in lakes can have a detrimental effect on fish life, leading to a reduction in fisheries' value. Pesticides, in particular, can interfere with fishes' osmoregulation and ionic regulation processes, which can negatively impact aquatic fauna Numerous pollutants have been found to hinder the growth and development of fish, as well as interfere with their reproductive cycles, either directly or indirectly. Additionally, pollutants have been observed to impair the reproduction of fish, leading to increased mortality rates Fish behaviour was also affected by pollutants .Because of the pollutants found in lake water, many types of diseases were observed in the fishes found in the lake

1. Alfonso, S., Gesto, M., & Sadoul, B. (2021). Temperature increase and its effects on fish stress physiology in the context of global warming. Journal of Fish Biology, 98, 1496– 1508. 2. Anttila, K., Dhillon, R. S., Boulding, E. G., Farrell, A. P., Glebe, B. D., Elliott, J. A. K., et al. (2013). Variation in temperature tolerance among families of Atlantic salmon (Salmo salar) is associated with hypoxia tolerance, ventricle size and myoglobin level. J. Exp. Biol. 216, 1183–1190. doi: 10.1242/jeb.080556 3. Arkoosh, M. R., Clemons, E., Huffman, P., Kagley, A. N., Casillas, E., Adams, N., et al. (2001). Increased susceptibility of juvenile chinook salmon to Vibriosis after exposure to chlorinated and aromatic compounds found in contaminated urban estuaries. J. Aquat. Anim. Health 13, 257–268. doi: 10.1577/1548-8667(2001)013<0257:isojcs>2.0.co;2 4. Baatrup, E., and Junge, M. (2001). Antiandrogenic pesticides disrupt sexual characteristics in the adult male guppy Poecilia reticulata. Environ. Health Perspect. 109, 1063–1070. doi: 10.1289/ehp.011091063 5. Bhatt NA, Sharma BK, Shwetanshumala, Shah T. Length-weight relationship and condition factor of Catla catla in Lake Pichhola, Udaipur, Rajasthan. International journal of fauna and biological studies. 2016;3(4):19-23. 6.Brodin, T., Fick, J., Jonsson, M., and Klaminder, J. (2013). Dilute concentrations of a psychiatric drug alter behavior of fish from natural populations. Science 339, 814–815. doi: 10.1126/science.1226850 7. Du, S. N. N., McCallum, E. S., Vaseghi-Shanjani, M., Choi, J. A., Warriner, T. R., Balshine, S., et al. (2018). Metabolic costs of exposure to wastewater effluent lead to compensatory adjustments in respiratory physiology in bluegill sunfish. Environ. Sci. Technol. 52, 801–811. doi: 10.1021/acs.est.7b03745 8. Du, S. N. N., Choi, J. A., McCallum, E. S., McLean, A. R., Borowiec, B. G., Balshine, S., et al. (2019). Metabolic implications of exposure to wastewater effluent in bluegill sunfish. Comp. 9. Biochem. Physiol. C Toxicol. Pharmacol. 224:108562. doi: 10.1016/j.cbpc.2019.108562 10. Giaquinto, P. C., de Sá, M. B., Sugihara, V. S., Gonçalves, B. B., Delício, H. C., and Barki, A. (2017). Effects of glyphosate-based herbicide sub-lethal concentrations on fish feeding behavior. Bull. Environ. Contam. Toxicol. 98, 460–464. doi: 10.1007/s00128-017-2037-2 11. Jacquin, L., Gandar, A., Aguirre-Smith, M., Perrault, A., Hénaff, M. L., Jong, L. D., et al. (2019). High temperature aggravates the effects of pesticides in goldfish. Ecotoxicol. Environ. Saf. 172, 255–264. doi: 10.1016/j.ecoenv.2019.01.085 12. Narasimha RK, Benarjee G. Physico-chemical factors influenced Plankton biodiversity and fish Abundance-a case study of nagaram tank of Warangal, Andhra Pradesh, 2013. 13. Ranga MM. Limnological studies of Ana Sagar lake at Ajmer with special reference to physicochemical properties and planktonic population. Ph.D. Thesis. M.D.S. Univ., Ajmer (Rajasthan), 1995. 14. Vijayvergiya A, Vyas R. Assessment of Primary Productivity and Plankton Population in Anasagar Lake Ajmer and Barali Lake Hurda. Journal of Drug Delivery and Therapeutics. 2019;9(4-s):1067-1071