Ecology of River Spiti

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Ecology of River Spiti, Lahaul—Spiti (Himachal Pradesh), India
Article Journal of Fisheries and Aquatic Science a January 2013
CSK HPKV Palampur
International Journal of Fisheries and Aquaculture Sciences.
ISSN 2248-9975 Volume 3, Number 2 (2013), pp. 131-141
© International Research Publication House

Ecology of River Spiti, Lahaul-Spiti (Himachal Pradeeh), India
lndu Sharmal and Rani Dhanzez
Zoological Slrvey of India, High Altitude Regional Centre,
Solan, Himachal Pradesh 173211, India.
E-mail: induzsi@gmaiI.com
Department of Fisheries COVAS CSKHPKV, Palamour,
Himachal Pradesh 176062, India.

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Abstract

The present study is conducted in view to appraise the ecology of Spiti River in the high altitude cold desert of Spiti valley, which is one of the fragile Himalayan Ecosystem. The diversity of planktonic, macrobenthic fauna along with physico-chemical parameters has been worked out. During monsoon season maximum  density, diversity of planktons and diversity of benthic fauna was recorded. The maxima of wealth of biological parameters during monsoon in spiti valley are disparate from the low and mid- hills, where highest is noticed during the winter or summer. Simpson’s diversity index was applied for calculation of species richness and species diversity.

Keywords: Altitude, Cold Desert, Planktons, Benthos, Species diversity.

1. Introduction

Spiti valley is fragile mountain ecosystem, desert mountain valley located high in the Himalayan mountains in the north-eastern part of Himachal-Pradesh. It is known as the land between India and Tibet. The Spiti River has its source far north on the eastern slopes of the mountain range between Lahaul and Spiti. The river is formed at the base of Kunzam range by the confluence of Kunzam La Togpo and the streams Kabzima and Pinglung. The River follows a long Wide course and interlocked by spurs that project from the foot of the plateaus on both sides. The length of the River within the spiti on the south-east is about 130 km. It continues in Kinnaur district up to a place known as Namgia (Khabo) and is about 14 Km upstream of Pooh (Kinnaur), where it joins the Satluj.

The Sutlej river basin in Himachal Pradesh covers an area of about 6,553 square kilometers. Spiti is on the northern border of Kinnaur – the boundary being formed by the rivers Spiti and Pare Chu near the Indo-Tibetan border. It is one of the largest tributary of the Satluj River. The Satluj River originates beyond Indian boarders in the Southern slopes of the Kailash mountainin near the Mansarovar Lake from Rakas lake, as Longcchen Khabab river (in Tibet) at 18500 ft. in the Tibetan Plateau. The Satluj is one of only three Trans
Himalayan rivers originating in the high Tibetan Plateau that cuts across the mighty Himalayan ranges. The other two are the Indus and the Brahmaputra. It enters India through a fearsome gorge near the Shipki La (Mountain pass on India-China Barder) at an altitude of 6, 608 m asl in district Kinnaur (Himachal-Pradesh), subsequently it flows through the cold tracts of Kinnaur to the hamlet of Wangtoo.

It is one of the major tributaries of the Indus River system. In its passage across Kinnaur, the Sutlej River successively crosses three great mountain ranges – the Zanskar range, the Great Himalayan range and the Dhauladhar range. To the east of the Satluj the valleys are narrow while in the west, they are wide and open. Many tributaries join the main Sutlej River one afler the other from the south. It is the largest among the five rivers of Himachal Pradesh. It enters Himachal at Shipkila (altitude is 6,608 meters) and flows in the South-Westerly direction through Kinnaur, Shimla, Kullu, Solan, Mandi and Bilaspur districts. Its course in Himachal Pradesh is 320 km from Rakastal, with famous tributaries viz. the Spiti, the Ropa, the Taiti, the Kashang, the Mulgaon, the Yula, the Wanger, the Throng and the Rupi as right bank tributaries, whereas the Tirung, the Gayathing, the Baspa, the Duling and the Soldang are left bank tributaries. Its total length is l,448 km. It leaves Himachal Pradesh to enter the plains of Punjab at Bhakhra, where the world’s highest gravity dam has been constmcted on this river.

Its total catchment area in Himachal Pradesh is 20,000 sq. km. The Satluj finally drains into the Indus in Pakistan. The catchment area of about 50,140 km. of Satluj River is located above the permanent snow line at an altitude of 4,500 metres. The upper tracts of the Satluj valley are under a permanent snow cover.
The main stream of the Spiti River, which is fed by the glaciers, is a perennial one, while some of the tributary streams disappear in the loose morain at the feet of the plateaus. During its course through the difficult, complex terrain, the Spiti is joined by a number of tributaries from both the sides. Those which join its right bank include: Chiomo, Gyundi, Rahtang, Ulah, Pin, Lungza Mano SJrah/, Pomograng, Mamdang
and SJmra; the lefi bank tributaries are: Thamar, Hanse, Thumna, Tagting, Thurrpa
Lumoa, Siila, Kaza, Lingti, Poh, Tabo, Karati, Gimdo and Parechu.

The demographic and physiographic characteristics of the catchments area of this tributary are identical to that of the Tibetan Plateau. Rainfall is scarce in this area. The altitude of the catchments area drained by river Spiti range between 3048m to 4570m. This catchments area is absolutely devoid of vegetation as a result the melting of snow from the glacier creates deep flow channels on the steep surface resulting enormous soil erosion. To promote the coldwater fisheries in this river it becomes necessary to
study the physico-chemical and biological parameters of this high altitude river.

1.1 Study Area

The four sampling sites were selected on this river. The first three sites are located towards upstream near village Leo. As this river passes to deep gorges where it can not be approached as a result site 1 is located near the new bridge of Leo and site 2 is 1 km down stream flom site 1 and this site receiving the enrich water passing through orchards and agricultural fields. The 3rd site is located near the confluence of river Spiti and rivulet Tobo. The river stretch is wide near site 1 to 3. The fourth site is at the confluence of river spiti and Satluj near Khab. The sampling has been made fiom aforesaid sites in different seasons during year 2009 and 2010.

2. Material and Methods

The analysis of different physico-chemical parameters and biological parameters was
done by following the standard methods (APHA, 1998; Adoni, 1985: Wards and
Wipple, 1959). Simpson’s diversity index was applied for calculation of species
richness and species diversity (Simpson, 1949).

3. Result and Discussion

3.1 Aquatic Ecology

River Spiti is contributing a huge volume of Water in River Satluj being main tributary
and its flow is dependent on the ls‘ and 2“d order streams and thus contributing in
shaping the current flow and nutrient composition. There is one rivulet “Tobe” joining
the River near village Leo indicating the contribution of water to the river from other
sources in the catchments area. The water current in the river Spiti is higher, which
ecologically is considered to be fast. At this velocity the current will remove all
particles less than 5 mm in diameter and will leave behind a stony bottom. The whole
stretch of River under study has very less riparian vegetation.
4. Present status of physico-chemical and biological characteristic
Water temperature is an important parameter which directly influences the aquatic
life in the ecosystem. It is one of the key water quality parameter in aquatic system
(Vannote and Sweeney 1980; Ward 1985; Hawkins et.aI. 1997). The surface water
temperature varies between 6 to 25°C and is greatly influenced by air temperature. The
minimum water temperature during the sampling period was recorded in October and
no collection of water sample could be made in this period due to frozen water. The
maximum water temperature was recorded from Leo in the month of May and June,
which depicts that water is suitable for cold water fisheries.
The oolour of water in all the sampling sites was found colorless and odourless. It
was recorded l and in some samples slightly more than l Hazan, and the optimum
limit is up to 5 Hazan units. pH is an important parameter for controlling the distribution of aqatic fauna and
flora. pH of the sampling sites is alkaline and fluctuated narrowly between 6.95 to 7.23
and lowest is recorded in the monsoon season. The pH recorded is within the
recommended range and sustenance of aquatic life.

Water velocity varies from 1.7 to 2.53m/sec. and considered as rapid one. The
velocity more than 0.152 m/sec. is considered as rapid one (Legler, 1977).
Dissolved oxygen is required for aquatic organisms for respiration and is also used
for decomposition of organic matter and other biological and chemical processes. The
dissolved oxygen value ranges from 9.2 to 11.56 mg/1. Cold water holds more
dissolved oxygen than the warm water. Higher dissolved oxygen recorded in post
monsoon and is due to low water temperature. Dissolved oxygen showed inverse
relationship with temperature in this season. The dissolved oxygen was recorded
highest during the Post monsoon and minima in the monsoon season.
The TDS is combined content of all substances (organic as well as inorganic)
present in water. The TDS values are high in all the sampling period. Its value ranges
from 182 to 306 mg/1. Srrenivasan (1978) was of the opinion that waters containing
less than 50mg/1 total dissolved solid are unproductive waters.
Alkalinity is important for fish and aquatic life because it protects or buffers
against pH changes (keeps the pH fairly constant) and makes water less vulnerable to
acid rain. Maximum alkalinity was recorded during post monsoon and minimum in
Monsoon. According to Moyle (1946), water bodies having total alkalinity >50mg/l
can be considered productive. During the present studies alkalinity varies from 84.0 to
148.08mg/1 and thus water is productive.
Total Hardness of water depends upon the amount of calcium and magnesium
salts or both. Its value ranges from 38.0 to 210.0 mg/1. Its value is directly related with
the TDS except during the Monsoon season where it is inversely related with
Hardness. Higher value during the post monsoon suggests that water is more
productive during this season.
The chloride value ranges from 7.96 to l4.74mg/l. The value of Chloride is
comparatively more in the pre monsoon season.
Nitrate-Nitrogen in natural waters is between 0.9 to 3.15 mg/1 and unpolluted
waters less than 4.0 mg/1 (http:// www.cess iupui.edu/). The value of nitrate-nitrogen
ranges fi”om 1.53 to 1.7 mg/l in the present study and is optimum for fishery.
According to Sturnn and Morgan (1981), the ionic dominance for the water bodies
are: Ca> Mg> Na> K and HCO3 > SO4 > Cl for fresh waters. The same ionic pattern is
recorded in the present study.
Biochemical Oxygen demand (BOD) is a measure of the amount of oxygen that
bacteria will consume while decomposing organic matter under aerobic conditions.

Ecology of River Saiti, Lahau/-So/’ti (Himachal Pradesh), India 135
BOD level varies 3.0 to 3.69. This implies that season did not have any significance
influence on BOD. The range < 5 is optimum for fishery as Well as for drinking
purpose.
Table 1: Average of physicochemical parameters of River Spiti.
No. Parameters Pre monsoon Monsoon Post monsoon
Water temperature UC 18 13 10
Color (Hazen) 1.0 <1 1.0
pH 7.23 6.95 7.15
Water velocity(m/s) 2.53 3.25 1.7
Dissolved oxygen mg/1 10.5 9.2 11.56
TDS, mg/l 290.0 182.0 306.0
Alkalinity, mg/1 98.5 84.0 148.0
Hardness, mg/1 165.0 38.0 210.0
O0\|CDU’IJ>(.Ol\J—\
9 Chloride, mg/l 14.74
7.96
11.25
10 Nitrate, mg/l 1.65
1.7
1.53
11 Calcium, mg/l 43.08
8.82
55.11
12 Magnesium, mg/1 14.32
5.59
18.85
13 Potassium, mg/l 12.71
6.54
12.23
14 Sodium, mg/1 27.00
10.5
23.93
15 BOD 3.0
3.69
3.10
5. Food chain organisms
The productivity of any aquatic water body depends on the amount of plankton and
benthos present in the said water body. The seasonal abundance and distribution of
Plankton is directly or indirectly related with the alkalinity, Water temperature, water
current, depth and organic nutrient available in the Water body. In other way we can
say that plankton (phytoplankton) growth and distribution depend on the carrying
capacity of the environment and on the nutrients concentration both intracellular and
extracellular. Plankton distribution and abundance are affected by season. The fish
productivity of said water body is directly related with its productivity as plankton and
benthos are the food of fishes.
5.1 Phytoplankton
The distribution of phytoplankton mainly depends on the temperature and nutrient
supply. Diatoms, flagellates and algae normally constitute the bulk of the
phytoplankton. A total of 27 species has been recorded. 15 species was reported during
pre monsoon, 20 species in post monsoon and 21 in monsoon period. Table (2)
depicted maximum diversity during monsoon. The phytoplankton species reported
during study period are: Arrphora, Acharanthes, Cocconeis, Cymbella, Cyclotdla,
Fragil/aria, Frustulia, Navicula, Q/nedra; Pinnularia, Diatoma, Gyrosigma, Nitzschia,
Tabellaria and Gomohonana of Bacillariophyceae, Anldstrodesmus Spirogyra,

136 /ndu Siarma & Rani Dhanze
U/othrix, Ped/’as‘rum, Mesotaenium, Qairataenia, Sairu/ina, Soenedesmus Cloder/’um,
and Cosmarium of Chl0rophycaea,’ Oscillatoria and Agmerellum of Cynophyceae.
(Table-2). The abundance of Navicula was noticed in all the season but 3/nedra only
in pre monsoon. The quantity of calcium is fairly good and which stimulates the
growth of diatoms particularly in pre monsoon when temperature and alkalinity was
also high and is in conformity with the view of Zafar (1964). The phytoplankton
density is comparatively higher during monsoon. The percentage population of
phytoplankton is higher than that of zooplankton which is the characteristics of a hill
stream. The total population reported from this river is sufficient to support the aquatic
life.
5.2 Zooplankton
These are the primary consumers and hence heterotrophs and secondary producers,
which are important indicator of the health of the aquatic ecosystem. Zooplankton
species found in the study area includes: Keratella monospina, Brachonus caudatus
Arcella $1 and Colpidium oolpoda. The maximum diversity is recoded during the
monsoon which is indicative of the fact that river is receiving organic matter this
period (Table-2).
5.3 Benthos
Benthos is the aquatic animals without backbones that are larger than V1 millimeter (the
size of a pencil dot). These animals are attached on rocks, logs, sediment, debris and
aquatic plants during some period of their life cycle. Their distribution depends on
water velocity, volume of water and nature of stream bed as well as presence of
nutrients. Table- 4 revealed the frequency and abundance of different taxas as a result
the percentage frequency of Ephemeropterans were varied from 18 to 47%. The
highest frequency was encountered during pre monsoon and lowest in post monsoon.
The Ephemeroptera were found most abundant Which indicates good Water quality as
well as favorable for biotic communities. The second dominating group is Trichoptera
and its frequency distribution was 8 to 53%. The highest frequency was reported in pre
monsoon. The Diptera, Coleoptera and Odonata were dominated in post monsoon and
their percentage of frequency was also high which may be due to deposition of organic
matter. However, Diptera is associated with poor water quality as they are more
resistant to pollution and is also observed by Depiereux el‘ al. (1983). The Molluscs
were rare and found only in pre monsoon. The total number of individuals per square
meter was high in pre monsoon due to favorable physico-chemical parameters.
The density of individuals per square meter is high at site 2 and 3 during all the
season (Table 5) whereas diversity index (Shanon-Weaver) was comparatively high
during monsoon because the taxas richness increases with increasing habitat diversity,
suitability and water quality (Plafkin et al. 1989). Thus the present study depicted the
abundance of Ephemeropterans and Trichopterans in pre monsoon where as in post
monsoon the dominating group was Dipterans which is presented by Chaoborus sp.
The Odonates were dominating in post monsoon but only at Khab (Site-4). The high
density of total benthos during pre monsoon depicted that there is no scarcity of food
for fishes migrated in upstream for breeding purpose.

Ecology of River Saiti, Lahaul-So/’ti (Himachal Pradesh), India 137
The physico-chemical parameters recorded were favorable for the productivity of
the stream during all the season and directly correlated with abundance of planktons
and benthos. It is elucidated from the present studies that during monsoon season
comparatively higher density and diversity of planktons are recorded and diversity of
benthic fauna is also recoded maximum for the period of the monsoon season except
density of benthos which is recorded high in the pre monsoon. Mostly, the diversity
and density of the planktonic and benthic fauna are minimum in monsoon season and
maximum in the winter and summer in the low and mid- hills. But while working in
the high altitude area of spiti valley the maxima of fauna is recorded in the monsoon
season because the area is rain shadow zone and geomorphology of the stream greatly
influence the hydrobiology of the stream.
5.4 Fish fauna and other fisheriesactivity
Spiti being one of the largest tributaries of the River Satluj with a characteristic fish
faunal element constitute a distinct, large, clear, cold-water mountain tributary. A
number of species reported from River Satluj (Tilak and Hussain 1977) while the fish
faunal diversity of river Spiti comprises only a few species that is Sthizothorax
richardsoni (Gray) belonging to the families Cyprinidae, and hill loaches i.e.
Triplophysa sp. belonging to family Cobitidae (Mehta and Uniyal, 2005 and Mehta
and Sharma, 2008). The fish species observed during field survey in the Spiti River are
– Triplophysa stoliczkae(Steindachner) and fry of &:hizothorax sp. The dominant long
distant migratory fish is Snow trout. The migratory phenomenon of the fish species is
directly related to its life cycle as the fishes move from one habitat to other for
spawning. The breeding migration starts with the onset of monsoon when a rise in
water level in search of suitable breeding grounds up-river. Even winter migration
takes place for the purpose of feeding in most of the fishes migrate towards down
stream. It is usually the periods of fish migration when fishing activities intensify in
the area. There is no fishing community but fishing is done by the riparian human
populations as well as the migrant laborers using illicit method of poaching or some
times hooks and line as well as cast net.
The studies in Cold Desert of Spiti valley has been undertaken for the first time and
can be base line for further studies. The hydrobiological studies should be a continuous
process for various reasons. One of the important is to know the impact of climatic
changes since the cold deseit, high altitudes are more vulnerable to ecological changes.
Further, the loaches (Triplophysa spp.) reported are endemic and are important from
conservation point of view.
Table 2: Planktonic diversity and abundance of River Spiti.
Taxas l Pre monsoon l Monsoon l Post monsoon
Phtoplankton
Bacillariopyhceae
Amphora
Acharanthes affinis l – –
Coconeis
+
++
+

/ndu Slarma & Rani Dhanze
Cymbella sp.
+
++
+
Cyclotella
meneghiana
+
Diatoma sp.
+
+
+
Fragilaria sp.
++
++
Frustulia sp.
+
+
+
Gomphonema sp.
+
+
+
Gyrosigma
accuminatus
+
Navicula radiosa
+++
%—4~+
+++
Nitzschia gracilis
++
Pinuularia braunii
++
++
‘P?
Synedra tabulata
+++
++
‘P?
Tabellaria sp.
+
+
Chlorophyoeae
Ankistrodesmus
falcatus
+
Cosmarium sp.
+
+
Closterium sp.
+
++
+
Mesotaenium sp.
+
++
Pediastrum
boryanum
+
Scenedesmus bijuga
++
Spirataenia
+
Spirogyra sp.
+
+
Spirulina princepes
+
+
Ulothrix sp.
++
+
Cynophyoeae
Agmenellum sp.
+
+
Oscillatoria sp.
++
++
Zooplan kton
Roti fera
Keratella monospina
Brachionus caudatus
+
+
+
I
Protozoa
Arcella sp.
Colpidium colpoda
+
+
– = absent, += prese
nt, ++= common, +++= abundance

Ecology of River Saiti, Lahau/-S2/’ti (Himachal Pradesh), India
Table 3: Planktons density and diversity index during different season.
139
planktons
Phyto- Density (individual/I) Diversity Index
Pre Monsoon Post Pre Monsoon Post monsoon
monsoon monsoon monsoon
Sitel
74.4
41.2
58.2
2.8
2.91
2.7
5
Site2
34.0
63.8
30.0
2.32
2.56
2.8
6
Site3
37.5
55.3
37.3
2.0
2.89
2.3
Site4
42.4
34.9
39.2
1.8
3.01
2.6
Zoo-
planktons
Density
Diversity Index
Location
Code
Pre
monsoon
M onsoon
Post
Pre Monsoon Post monsoon
monsoon monsoon
Sitel
0.4
0.4
0.4 0.2
0.8
0.49
Site2
0.5
0.4
1.1
0.5
4
Site3
0.4
0.6
1.0
0.5
Site4
0.5
0.6
0.2
Tab|e4: Benthic diversity and abundance of River spiti.
Pre M onsoon M onsoon Post monsoon
Cy (%)
C6
Frequen Abundan Frequen Abundan Frequen Abundan
C€
Ephemeroptera(Ephe 47 +++
mere/Ia so)
Cy (%) Ce Cy (%)
35 +++ 18
++
Di ptera (Chaoborus) –
10
+
40
+++
Trichoptera 53.1 +++
(H ydroptila so.)
45
+—I~+
8
+
Col eoptera –
(Ptillodactylidae)
5
+
18
++
Odonata
5
+
16
++
Mollusca
1 +
Total population
(indv./sq.m)
-P
\l
_\
O
_\4
O1
– : absent, += present, ++= common, +++= abundance.
Table 5: Benthic density and diversity index during different season.
Total I Density (individual/sq.m) I Diversity Index
benthos
monsoon monsoon monsoon monsoon
I Pre IMonsooI Post I Pre IMonsooI Post
n n
Site-1I 34 I 10I 10 I 2.8 |2.91
| 0.9503

140 /ndu Siarma & Rani Dhanze
Site2 1 42 1 12 1 15 1 2.32 1 2.56 1 2.86
Site3 1 84 1 15 1 20 1 2.0 1 2.89 1 2.3
Site4 1 22 1 8 1 12 1 1.8 1 3.01 1 0.8196
Acknowledgement
The authors are grateful to the Director, Zoological Survey of India, Kolkata and
Officer-in-charge, HARC, ZSI, Solan (H.P.) for encouragement and providing
facilities. The reviewer (Anonymous) is also thankful for useful corrections and
suggestions.
References
[l] Adoni, A.D 1985. Workbook of Limnology. Prtibha publisher. 216 pp.
[2] APHA 1998. Standard method for the examination of Water and waste-water.
20th (ed) Washington D.C. l2l3pp.
[3] Asper, V.I. and W.O. Smith, (Jr.) 1999. Partice fluxes during Austral spring
and summer in the southern Ross Sea (Antactica). Joumal of Geophysical
Research 104.
[4] Depiereux E, Feytmans E, Micha J.C. 1983. Utilization critique de I’
analyseen components principals et du cluster analysis pour la description
d’invertebrates benthiques eneau douce. 40:81-94.
[5] Hawkins C P, Hogue J N , deeker L m feminella J W 1997. Channel
Morphology, Water temperature and assemblage structure of stream insects. J.
North Am Benthol Soc l6: 728-749.
[6] Lagler, K. F. 1977. Freshwater Fishery Biology, W.M. C. B. C., USA, pp.
421.
[7] Mehta, H.S. and Uniyal, D.P. 2005. Pisces Zool. Surv. India, Fauna of
Western Himalaya (Part-2): 255-268.
[8] Mehta, H.S. and Sharma, I. 2008. Pisces Fauna of Pin Valley National Park,
Conservation Area Series, 34: 89-92.
[9] Plafkin, JL., Barbour, M.T., Porter, K.D., Gross, S.K., and Hughes, R.M.
1989. Rapid Bioassessment Protocols for Use in Streams and Rivers: Benthic
Macroinvertebrates and Fish. U.S. Environmental Protection Agency. EPA
440/4-89.001. (Washington, D.C.: U.S. EPA).
[10] Shannon C. E. and W. W. Weaver 1963. The mathematical Theory of
Communication. University of Illinois Press, Urbana. 125pp.
[ll] Smith, W.D.Jr., Nelson, D.M., Ditullio, G.R. & A.R.L. Eventer 1996.
Temporal and spatial patterns in the Ross sea. Phytoplankton biomass,
elemental composition, productivity and growth rates. J. Geophysical
Research, lO1(18) 455- 466.
[12] Simpson, E.H. 1949. Measurement ofdiversity. Nature 168: 688.
[13] Sreenivasassan, A. 1978. Limnological and fisheries management-5th FAO/
SI DA Workshop on Aquatic pollution in relation to protection of living

Ecology of River Saiti, Lahaul-So/’ti (Himachal Pradesh), India 141
resources. Scientific and administrative basis for management measures,
Manita, Phillippines.
Stumm W. and Morgan J.J. 1981. Aquatic Chemistry. Wiley. New York.
780pp.
Tilak, R. and A. Husian 1977. A checklist of the fishes of Himachal Pradesh.
Z001. Jb. Syst. Bd. 104:265-301.
Vannote R. L., Sweeney BW 1980. Geographical analysis of thermal
equilibria : a conceptual model for evaluating the effect of natural and
modified thermal regimes on aquatic insect communities. Am Nat 115: 667-
695.
Ward, H. B. and G.C. Whipple 1959. Freshwater Biology (2nd Edn.). John
Wiley and sons. Inc. New Yark 1248 pp.
Zafar, A. R. 1964. On the ecology of algae in certain ponds of Hyderabad,
India. Physicochemical complex. Hydrobiologia, 23:179-195.
Ward, IV 1985. Thermal characteristics of running waters. Hydrobiologia
125: 31-46.

/ndu Slarma & Rani Dhanze

Article Journal of Fisheries and Aquatic Science a January 2013
CSK HPKV Palampur
14 PUBLICATIONS 1 C|TATlON

International Journal of Fisheries and Aquaculture Sciences.
ISSN 2248-9975 Volume 3, Number 2 (2013), pp. 131-141
© International Research Publication House

Ecology of River Spiti, Lahaul-Spiti (Himachal Pradeeh), India
lndu Sharmal and Rani Dhanzez
Zoological Slrvey of India, High Altitude Regional Centre,
Solan, Himachal Pradesh 173211, India.
E-mail: ’nduzsi@gmaiI.com
Department of Fisheries COVAS CSKHPKV, Palamour,
Himachal Pradesh 176062, India.

Abstract

The present study is conducted in view to appraise the ecology of Spiti
River in the high altitude cold desert of Spiti valley, which is one of
the fragile Himalayan Ecosystem. The diversity of planktonic,
macrobenthic fauna along with physico-chemical parameters has been
worked out. During monsoon season maximum density, diversity of
planktons and diversity of benthic fauna was recorded. The maxima of
wealth of biological parameters during monsoon in spiti valley are
disparate from the low and mid- hills, where highest is noticed during
the winter or summer. Simpson’s diversity index was applied for
calculation of species richness and species diversity.
Keywords: Altitude, Cold Desert, Planktons, Benthos, Species
diversity.
1. Introduction
Spiti valley is fragile mountain ecosystem, desert mountain valley located high in the
Himalayan mountains in the north-eastern part of Himachal-Pradesh. It is known as the
land between India and Tibet. The Spiti River has its source far north on the eastern
slopes of the mountain range between Lahaul and Spiti. The river is formed at the base
of Kunzam range by the confluence of Kunzam La Togpo and the streams Kabzima
and Pinglung. The River follows a long Wide course and interlocked by spurs that
project from the foot of the plateaus on both sides. The length of the River within the
spiti on the south-east is about 130 km. It continues in Kinnaur district up to a place
known as Namgia (Khabo) and is about 14 Km upstream of Pooh (Kinnaur), where it

132 /ndu Siarma & Rani Dhanze
joins the Satluj. The Sutlej river basin in Himachal Pradesh covers an area of about
6,553 square kilometers. Spiti is on the northern border of Kinnaur – the boundary
being formed by the rivers Spiti and Pare Chu near the Indo-Tibetan border. It is one of
the largest tributary of the Satluj River.
The Satluj River originates beyond Indian boarders in the Southern slopes of the
Kailash mountainin near the Mansarovar Lake from Rakas lake, as Longcchen Khabab
river (in Tibet) at 18500 ft. in the Tibetan Plateau. The Satluj is one of only three Trans
Himalayan rivers originating in the high Tibetan Plateau that cuts across the mighty
Himalayan ranges. The other two are the Indus and the Brahmaputra. It enters India
through a fearsome gorge near the Shipki La (Mountain pass on India-China Boarder)
at an altitude of 6, 608 m asl in district Kinnaur (Himachal-Pradesh), subsequently it
flows through the cold tracts of Kinnaur to the hamlet of Wangtoo. It is one of the
major tributaries of the Indus River system. In its passage across Kinnaur, the Sutlej
River successively crosses three great mountain ranges – the Zanskar range, the Great
Himalayan range and the Dhauladhar range. To the east of the Satluj the valleys are
narrow while in the west, they are wide and open. Many tributaries join the main Sutlej
River one afler the other from the south. It is the largest among the five rivers of
Himachal Pradesh. It enters Himachal at Shipkila (altitude is 6,608 meters) and flows
in the South-Westerly direction through Kinnaur, Shimla, Kullu, Solan, Mandi and
Bilaspur districts. Its course in Himachal Pradesh is 320 km from Rakastal, with
famous tributaries viz. the Spiti, the Ropa, the Taiti, the Kashang, the Mulgaon, the
Yula, the Wanger, the Throng and the Rupi as right bank tributaries, whereas the
Tirung, the Gayathing, the Baspa, the Duling and the Soldang are left bank tributaries.
Its total length is l,448 km. It leaves Himachal Pradesh to enter the plains of Punjab at
Bhakhra, where the world’s highest gravity dam has been constmcted on this river. Its
total catchment area in Himachal Pradesh is 20,000 sq. km. The Satluj finally drains
into the Indus in Pakistan. The catchment area of about 50,140 km. of Satluj River is
located above the permanent snow line at an altitude of 4,500 metres. The upper tracts
of the Satluj valley are under a permanent snow cover.
The main stream of the Spiti River, which is fed by the glaciers, is a perennial one,
while some of the tributary streams disappear in the loose morain at the feet of the
plateaus. During its course through the difficult, complex terrain, the Spiti is joined by
a number of tributaries from both the sides. Those which join its right bank include:
Chiomo, Gyundi, Rahtang, Ulah, Pin, Lungza Mano SJrah/, Pomograng, Mamdang
and SJmra; the lefi bank tributaries are: Thamar, Hanse, Thumna, Tagting, Thurrpa
Lumoa, Siila, Kaza, Lingti, Poh, Tabo, Karati, Gimdo and Parechu.
The demographic and physiographic characteristics of the catchments area of this
tributary are identical to that of the Tibetan Plateau. Rainfall is scarce in this area. The
altitude of the catchments area drained by river Spiti range between 3048m to 457Om.
This catchments area is absolutely devoid of vegetation as a result the melting of snow
from the glacier creates deep flow channels on the steep surface resulting enormous
soil erosion. To promote the coldwater fisheries in this river it becomes necessary to
study the physico-chemical and biological parameters of this high altitude river.

Ecology of River Saiti, Lahaul-So/’ti (Himachal Pradesh), India 133
1.1 Study Area
The four sampling sites were selected on this river. The first three sites are located
towards upstream near village Leo. As this river passes to deep gorges where it can not
be approached as a result site 1 is located near the new bridge of Leo and site 2 is 1 km
down stream flom site 1 and this site receiving the enrich water passing through
orchards and agricultural fields. The 3“ site is located near the confluence of river Spiti
and rivulet Tobo. The river stretch is wide near site 1 to 3. The fourth site is at the
confluence of river spiti and Satluj near Khab. The sampling has been made fiom
aforesaid sites in different seasons during year 2009 and 2010.
2. Material and Methods
The analysis of different physico-chemical parameters and biological parameters was
done by following the standard methods (APHA, 1998; Adoni, 1985: Wards and
Wipple, 1959). Simpson’s diversity index was applied for calculation of species
richness and species diversity (Simpson, 1949).
3. Result and Discussion
3.1 Aquatic Eoology
River spiti is contributing a huge volume of Water in River Satluj being main tributary
and its flow is dependent on the ls‘ and 2“d order streams and thus contributing in
shaping the current flow and nutrient composition. There is one rivulet “Tobe” joining
the River near village Leo indicating the contribution of water to the river from other
sources in the catchments area. The water current in the river Spiti is higher, which
ecologically is considered to be fast. At this velocity the current will remove all
particles less than 5 mm in diameter and will leave behind a stony bottom. The whole
stretch of River under study has very less riparian vegetation.
4. Present status of physico-chemical and biological characteristic
Water temperature is an important parameter which directly influences the aquatic
life in the ecosystem. It is one of the key water quality parameter in aquatic system
(Vannote and Sweeney 1980; Ward 1985; Hawkins et.aI. 1997). The surface water
temperature varies between 6 to 25°C and is greatly influenced by air temperature. The
minimum water temperature during the sampling period was recorded in October and
no collection of water sample could be made in this period due to frozen water. The
maximum water temperature was recorded from Leo in the month of May and June,
which depicts that water is suitable for cold water fisheries.
The oolour of water in all the sampling sites was found colorless and odourless. It
was recorded l and in some samples slightly more than l Hazan, and the optimum
limit is up to 5 Hazan units.

134 /ndu Siarma & Rani Dhanze
pH is an important parameter for controlling the distribution of aqatic fauna and
flora. pH of the sampling sites is alkaline and fluctuated narrowly between 6.95 to 7.23
and lowest is recorded in the monsoon season. The pH recorded is within the
recommended range and sustenance of aquatic life.
Water velocity varies from 1.7 to 2.53m/sec. and considered as rapid one. The
velocity more than 0.152 m/sec. is considered as rapid one (Legler, 1977).
Dissolved oxygen is required for aquatic organisms for respiration and is also used
for decomposition of organic matter and other biological and chemical processes. The
dissolved oxygen value ranges from 9.2 to 11.56 mg/1. Cold water holds more
dissolved oxygen than the warm water. Higher dissolved oxygen recorded in post
monsoon and is due to low water temperature. Dissolved oxygen showed inverse
relationship with temperature in this season. The dissolved oxygen was recorded
highest during the Post monsoon and minima in the monsoon season.
The TDS is combined content of all substances (organic as well as inorganic)
present in water. The TDS values are high in all the sampling period. Its value ranges
from 182 to 306 mg/1. Srrenivasan (1978) was of the opinion that waters containing
less than 50mg/1 total dissolved solid are unproductive waters.
Alkalinity is important for fish and aquatic life because it protects or buffers
against pH changes (keeps the pH fairly constant) and makes water less vulnerable to
acid rain. Maximum alkalinity was recorded during post monsoon and minimum in
Monsoon. According to Moyle (1946), water bodies having total alkalinity >50mg/l
can be considered productive. During the present studies alkalinity varies from 84.0 to
148.08mg/1 and thus water is productive.
Total Hardness of water depends upon the amount of calcium and magnesium
salts or both. Its value ranges from 38.0 to 210.0 mg/1. Its value is directly related with
the TDS except during the Monsoon season where it is inversely related with
Hardness. Higher value during the post monsoon suggests that water is more
productive during this season.
The chloride value ranges from 7.96 to l4.74mg/l. The value of Chloride is
comparatively more in the pre monsoon season.
Nitrate-Nitrogen in natural waters is between 0.9 to 3.15 mg/1 and unpolluted
waters less than 4.0 mg/1 (http:// www.cess iupui.edu/). The value of nitrate-nitrogen
ranges fi”om 1.53 to 1.7 mg/l in the present study and is optimum for fishery.
According to Sturnn and Morgan (1981), the ionic dominance for the water bodies
are: Ca> Mg> Na> K and HCO3 > SO4 > Cl for fresh waters. The same ionic pattern is
recorded in the present study.
Biochemical Oxygen demand (BOD) is a measure of the amount of oxygen that
bacteria will consume while decomposing organic matter under aerobic conditions.

Ecology of River Saiti, Lahau/-So/’ti (Himachal Pradesh), India 135
BOD level varies 3.0 to 3.69. This implies that season did not have any significance
influence on BOD. The range < 5 is optimum for fishery as Well as for drinking
purpose.
Table 1: Average of physicochemical parameters of River Spiti.
No. Parameters Pre monsoon Monsoon Post monsoon
Water temperature UC 18 13 10
Color (Hazen) 1.0 <1 1.0 pH 7.23 6.95 7.15 Water velocity(m/s) 2.53 3.25 1.7 Dissolved oxygen mg/1 10.5 9.2 11.56 TDS, mg/l 290.0 182.0 306.0 Alkalinity, mg/1 98.5 84.0 148.0 Hardness, mg/1 165.0 38.0 210.0 O0\|CDU’IJ>(.Ol\J—\
9 Chloride, mg/l 14.74
7.96
11.25
10 Nitrate, mg/l 1.65
1.7
1.53
11 Calcium, mg/l 43.08
8.82
55.11
12 Magnesium, mg/1 14.32
5.59
18.85
13 Potassium, mg/l 12.71
6.54
12.23
14 Sodium, mg/1 27.00
10.5
23.93
15 BOD 3.0
3.69
3.10
5. Food chain organisms
The productivity of any aquatic water body depends on the amount of plankton and
benthos present in the said water body. The seasonal abundance and distribution of
Plankton is directly or indirectly related with the alkalinity, Water temperature, water
current, depth and organic nutrient available in the Water body. In other way we can
say that plankton (phytoplankton) growth and distribution depend on the carrying
capacity of the environment and on the nutrients concentration both intracellular and
extracellular. Plankton distribution and abundance are affected by season. The fish
productivity of said water body is directly related with its productivity as plankton and
benthos are the food of fishes.
5.1 Phytoplankton
The distribution of phytoplankton mainly depends on the temperature and nutrient
supply. Diatoms, flagellates and algae normally constitute the bulk of the
phytoplankton. A total of 27 species has been recorded. 15 species was reported during
pre monsoon, 20 species in post monsoon and 21 in monsoon period. Table (2)
depicted maximum diversity during monsoon. The phytoplankton species reported
during study period are: Arrphora, Acharanthes, Cocconeis, Cymbella, Cyclotdla,
Fragil/aria, Frustulia, Navicula, Q/nedra; Pinnularia, Diatoma, Gyrosigma, Nitzschia,
Tabellaria and Gomohonana of Bacillariophyceae, Anldstrodesmus Spirogyra,

136 /ndu Siarma & Rani Dhanze
U/othrix, Ped/’as‘rum, Mesotaenium, Qairataenia, Sairu/ina, Soenedesmus Cloder/’um,
and Cosmarium of Chl0rophycaea,’ Oscillatoria and Agmerellum of Cynophyceae.
(Table-2). The abundance of Navicula was noticed in all the season but 3/nedra only
in pre monsoon. The quantity of calcium is fairly good and which stimulates the
growth of diatoms particularly in pre monsoon when temperature and alkalinity was
also high and is in conformity with the view of Zafar (1964). The phytoplankton
density is comparatively higher during monsoon. The percentage population of
phytoplankton is higher than that of zooplankton which is the characteristics of a hill
stream. The total population reported from this river is sufficient to support the aquatic
life.
5.2 Zooplankton
These are the primary consumers and hence heterotrophs and secondary producers,
which are important indicator of the health of the aquatic ecosystem. Zooplankton
species found in the study area includes: Keratella monospina, Brachonus caudatus
Arcella $1 and Colpidium oolpoda. The maximum diversity is recoded during the
monsoon which is indicative of the fact that river is receiving organic matter this
period (Table-2).
5.3 Benthos
Benthos is the aquatic animals without backbones that are larger than V1 millimeter (the
size of a pencil dot). These animals are attached on rocks, logs, sediment, debris and
aquatic plants during some period of their life cycle. Their distribution depends on
water velocity, volume of water and nature of stream bed as well as presence of
nutrients. Table- 4 revealed the frequency and abundance of different taxas as a result
the percentage frequency of Ephemeropterans were varied from 18 to 47%. The
highest frequency was encountered during pre monsoon and lowest in post monsoon.
The Ephemeroptera were found most abundant Which indicates good Water quality as
well as favorable for biotic communities. The second dominating group is Trichoptera
and its frequency distribution was 8 to 53%. The highest frequency was reported in pre
monsoon. The Diptera, Coleoptera and Odonata were dominated in post monsoon and
their percentage of frequency was also high which may be due to deposition of organic
matter. However, Diptera is associated with poor water quality as they are more
resistant to pollution and is also observed by Depiereux el‘ al. (1983). The Molluscs
were rare and found only in pre monsoon. The total number of individuals per square
meter was high in pre monsoon due to favorable physico-chemical parameters.
The density of individuals per square meter is high at site 2 and 3 during all the
season (Table 5) whereas diversity index (Shanon-Weaver) was comparatively high
during monsoon because the taxas richness increases with increasing habitat diversity,
suitability and water quality (Plafkin et al. 1989). Thus the present study depicted the
abundance of Ephemeropterans and Trichopterans in pre monsoon where as in post
monsoon the dominating group was Dipterans which is presented by Chaoborus sp.
The Odonates were dominating in post monsoon but only at Khab (Site-4). The high
density of total benthos during pre monsoon depicted that there is no scarcity of food
for fishes migrated in upstream for breeding purpose.

Ecology of River Saiti, Lahaul-So/’ti (Himachal Pradesh), India 137
The physico-chemical parameters recorded were favorable for the productivity of
the stream during all the season and directly correlated with abundance of planktons
and benthos. It is elucidated from the present studies that during monsoon season
comparatively higher density and diversity of planktons are recorded and diversity of
benthic fauna is also recoded maximum for the period of the monsoon season except
density of benthos which is recorded high in the pre monsoon. Mostly, the diversity
and density of the planktonic and benthic fauna are minimum in monsoon season and
maximum in the winter and summer in the low and mid- hills. But while working in
the high altitude area of spiti valley the maxima of fauna is recorded in the monsoon
season because the area is rain shadow zone and geomorphology of the stream greatly
influence the hydrobiology of the stream.
5.4 Fish fauna and other fisheriesactivity
Spiti being one of the largest tributaries of the River Satluj with a characteristic fish
faunal element constitute a distinct, large, clear, cold-water mountain tributary. A
number of species reported from River Satluj (Tilak and Hussain 1977) while the fish
faunal diversity of river Spiti comprises only a few species that is Sthizothorax
richardsoni (Gray) belonging to the families Cyprinidae, and hill loaches i.e.
Triplophysa sp. belonging to family Cobitidae (Mehta and Uniyal, 2005 and Mehta
and Sharma, 2008). The fish species observed during field survey in the Spiti River are
– Triplophysa stoliczkae(Steindachner) and fry of &:hizothorax sp. The dominant long
distant migratory fish is Snow trout. The migratory phenomenon of the fish species is
directly related to its life cycle as the fishes move from one habitat to other for
spawning. The breeding migration starts with the onset of monsoon when a rise in
water level in search of suitable breeding grounds up-river. Even winter migration
takes place for the purpose of feeding in most of the fishes migrate towards down
stream. It is usually the periods of fish migration when fishing activities intensify in
the area. There is no fishing community but fishing is done by the riparian human
populations as well as the migrant laborers using illicit method of poaching or some
times hooks and line as well as cast net.
The studies in Cold Desert of Spiti valley has been undertaken for the first time and
can be base line for further studies. The hydrobiological studies should be a continuous
process for various reasons. One of the important is to know the impact of climatic
changes since the cold deseit, high altitudes are more vulnerable to ecological changes.
Further, the loaches (Triplophysa spp.) reported are endemic and are important from
conservation point of view.
Table 2: Planktonic diversity and abundance of River Spiti.
Taxas l Pre monsoon l Monsoon l Post monsoon
Phtoplankton
Bacillariopyhceae
Amphora
Acharanthes affinis l – –
Coconeis
+
++
+

/ndu Slarma & Rani Dhanze
Cymbella sp.
+
++
+
Cyclotella
meneghiana
+
Diatoma sp.
+
+
+
Fragilaria sp.
++
++
Frustulia sp.
+
+
+
Gomphonema sp.
+
+
+
Gyrosigma
accuminatus
+
Navicula radiosa
+++
%—4~+
+++
Nitzschia gracilis
++
Pinuularia braunii
++
++
‘P?
Synedra tabulata
+++
++
‘P?
Tabellaria sp.
+
+
Chlorophyoeae
Ankistrodesmus
falcatus
+
Cosmarium sp.
+
+
Closterium sp.
+
++
+
Mesotaenium sp.
+
++
Pediastrum
boryanum
+
Scenedesmus bijuga
++
Spirataenia
+
Spirogyra sp.
+
+
Spirulina princepes
+
+
Ulothrix sp.
++
+
Cynophyoeae
Agmenellum sp.
+
+
Oscillatoria sp.
++
++
Zooplan kton
Roti fera
Keratella monospina
Brachionus caudatus
+
+
+
I
Protozoa
Arcella sp.
Colpidium colpoda
+
+
– = absent, += prese
nt, ++= common, +++= abundance

Ecology of River Saiti, Lahau/-S2/’ti (Himachal Pradesh), India
Table 3: Planktons density and diversity index during different season.
139
planktons
Phyto- Density (individual/I) Diversity Index
Pre Monsoon Post Pre Monsoon Post monsoon
monsoon monsoon monsoon
Sitel
74.4
41.2
58.2
2.8
2.91
2.7
5
Site2
34.0
63.8
30.0
2.32
2.56
2.8
6
Site3
37.5
55.3
37.3
2.0
2.89
2.3
Site4
42.4
34.9
39.2
1.8
3.01
2.6
Zoo-
planktons
Density
Diversity Index
Location
Code
Pre
monsoon
M onsoon
Post
Pre Monsoon Post monsoon
monsoon monsoon
Sitel
0.4
0.4
0.4 0.2
0.8
0.49
Site2
0.5
0.4
1.1
0.5
4
Site3
0.4
0.6
1.0
0.5
Site4
0.5
0.6
0.2
Tab|e4: Benthic diversity and abundance of River spiti.
Pre M onsoon M onsoon Post monsoon
Cy (%)
C6
Frequen Abundan Frequen Abundan Frequen Abundan
C€
Ephemeroptera(Ephe 47 +++
mere/Ia so)
Cy (%) Ce Cy (%)
35 +++ 18
++
Di ptera (Chaoborus) –
10
+
40
+++
Trichoptera 53.1 +++
(H ydroptila so.)
45
+—I~+
8
+
Col eoptera –
(Ptillodactylidae)
5
+
18
++
Odonata
5
+
16
++
Mollusca
1 +
Total population
(indv./sq.m)
-P
\l
_\
O
_\4
O1
– : absent, += present, ++= common, +++= abundance.
Table 5: Benthic density and diversity index during different season.
Total I Density (individual/sq.m) I Diversity Index
benthos
monsoon monsoon monsoon monsoon
I Pre IMonsooI Post I Pre IMonsooI Post
n n
Site-1I 34 I 10I 10 I 2.8 |2.91
| 0.9503

140 /ndu Siarma & Rani Dhanze
Site2 1 42 1 12 1 15 1 2.32 1 2.56 1 2.86
Site3 1 84 1 15 1 20 1 2.0 1 2.89 1 2.3
Site4 1 22 1 8 1 12 1 1.8 1 3.01 1 0.8196
Acknowledgement
The authors are grateful to the Director, Zoological Survey of India, Kolkata and
Officer-in-charge, HARC, ZSI, Solan (H.P.) for encouragement and providing
facilities. The reviewer (Anonymous) is also thankful for useful corrections and
suggestions.
References
[l] Adoni, A.D 1985. Workbook of Limnology. Prtibha publisher. 216 pp.
[2] APHA 1998. Standard method for the examination of Water and waste-water.
20th (ed) Washington D.C. l2l3pp.
[3] Asper, V.I. and W.O. Smith, (Jr.) 1999. Partice fluxes during Austral spring
and summer in the southern Ross Sea (Antactica). Joumal of Geophysical
Research 104.
[4] Depiereux E, Feytmans E, Micha J.C. 1983. Utilization critique de I’
analyseen components principals et du cluster analysis pour la description
d’invertebrates benthiques eneau douce. 40:81-94.
[5] Hawkins C P, Hogue J N , deeker L m feminella J W 1997. Channel
Morphology, Water temperature and assemblage structure of stream insects. J.
North Am Benthol Soc l6: 728-749.
[6] Lagler, K. F. 1977. Freshwater Fishery Biology, W.M. C. B. C., USA, pp.
421.
[7] Mehta, H.S. and Uniyal, D.P. 2005. Pisces Zool. Surv. India, Fauna of
Western Himalaya (Part-2): 255-268.
[8] Mehta, H.S. and Sharma, I. 2008. Pisces Fauna of Pin Valley National Park,
Conservation Area Series, 34: 89-92.
[9] Plafkin, JL., Barbour, M.T., Porter, K.D., Gross, S.K., and Hughes, R.M.
1989. Rapid Bioassessment Protocols for Use in Streams and Rivers: Benthic
Macroinvertebrates and Fish. U.S. Environmental Protection Agency. EPA
440/4-89.001. (Washington, D.C.: U.S. EPA).
[10] Shannon C. E. and W. W. Weaver 1963. The mathematical Theory of
Communication. University of Illinois Press, Urbana. 125pp.
[ll] Smith, W.D.Jr., Nelson, D.M., Ditullio, G.R. & A.R.L. Eventer 1996.
Temporal and spatial patterns in the Ross sea. Phytoplankton biomass,
elemental composition, productivity and growth rates. J. Geophysical
Research, lO1(18) 455- 466.
[12] Simpson, E.H. 1949. Measurement ofdiversity. Nature 168: 688.
[13] Sreenivasassan, A. 1978. Limnological and fisheries management-5th FAO/
SI DA Workshop on Aquatic pollution in relation to protection of living

Ecology of River Saiti, Lahaul-So/’ti (Himachal Pradesh), India 141
resources. Scientific and administrative basis for management measures,
Manita, Phillippines.
Stumm W. and Morgan J.J. 1981. Aquatic Chemistry. Wiley. New York.
780pp.
Tilak, R. and A. Husian 1977. A checklist of the fishes of Himachal Pradesh.
Z001. Jb. Syst. Bd. 104:265-301.
Vannote R. L., Sweeney BW 1980. Geographical analysis of thermal
equilibria : a conceptual model for evaluating the effect of natural and
modified thermal regimes on aquatic insect communities. Am Nat 115: 667-
695.
Ward, H. B. and G.C. Whipple 1959. Freshwater Biology (2nd Edn.). John
Wiley and sons. Inc. New Yark 1248 pp.
Zafar, A. R. 1964. On the ecology of algae in certain ponds of Hyderabad,
India. Physicochemical complex. Hydrobiologia, 23:179-195.
Ward, IV 1985. Thermal characteristics of running waters. Hydrobiologia
125: 31-46.

/ndu Slarma & Rani Dhanze