Rainfall and Spring Discharge Patterns in Two Small Drainage Catchments in the Western Himalayan Mountains, India

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1 The Environmentalist, 24, 19 28, Kluwer Academic Publishers. Manufactured in The Netherlands. Rainfall and Discharge Patterns in Two Small Drainage Catchments in the Western Himalayan Mountains, India GIRISH C.S. NEGI and VARUN JOSHI G.B. Pant Institute of Himalayan Environment and Development, Kosi-Katarmal, Almora , Uttaranchal, India Summary. Relationship between rainfall and spring study is important to understand hydrological behaviour of springs and water resources management. In the Himalayan mountains springs are the freshwater sources for household consumption. We studied six springs of different recharge area characteristics in two micro-watersheds in western Himalayan mountains in India. Based on the recharge area geology these springs were divided into fracture/joint (FR/JT) and fracture/joint/colluvium (FR/JT/COLL). We found a strong positive relationship between rainfall and spring. Peak spring coincided with peak rainfall in two FR/JT/COLL springs, which was delayed by about one month in FR/JT springs. Mean annual was about two times greater for FR/JT/COLL springs than the FR/JT springs (6.47 vs liter per minute). But spring per 1000 L of rainfall in spring recharge area for FR/JT springs was about 2.3 times greater than the FR/JT/COLL springs (49 vs. 21 liter per minute). In the FR/JT springs, rainfall in spring recharge area and spring were weakly related (r = 0.174), while they were strongly related in FR/JT/COLL springs (r = 0.595). In the former category of springs decline in was gradual, while it was rapid in the latter category of springs. Therefore, with regard to sustained supply of water for household consumption FR/JT springs can be considered more suitable. Land use and land cover such as moderately grazed pasture, abandoned agricultural terraces and few trees but dense growth of bushes and oak forest in the spring recharge area were found conducive for spring and may be promoted for long-term water resource conservation in this region. Keywords: geology, rainfall, spring, spring recharge area, western Himalayan mountains Introduction In the Indian Himalayan mountains springs provide the main sources of freshwater for drinking and other household consumption. s occur where sloping ground and impermeable strata intersect with the ground water table. The water sources of such springs, in most of the cases, are unconfined aquifers where the flow of water is under gravity. Occurrence of unconfined springs depends mainly on recharge area characteristics, such as permeability of top soil, soil structure and depth, geology of the area, slope of the ground, and surface covered by vegetation (Valdiya and Bar- Corresponding author. negigcs@yahoo.co.in tarya, 1991). Therefore, spring water yield both during rainy and non-rainy seasons has been found to be affected by both rainfall and the recharge area characteristics (Negi and Joshi, 1996). water yield has received little investigation in this region. In the eastern Himalaya, Rai et al. (1998) found that the rate and total flow in springs were highly correlated with rainfall pattern. Recession of seasonal springs was much more rapid than perennial springs. Valdiya and Bartarya (1991) recognized 8 types of springs based on geology, nature of water-bearing formations, and conditions governing their formations in central Himalaya. s originating from fluvial deposits produced water at the highest rate (mean = L/d) and those originating from colluvium at the

2 20 Negi and Joshi lowest rate ( L/d). Different types of springs behaved differently from one another in terms of water yield, base flow, seasonal pattern, etc. Rai et al. (1998) found a great variation in mean annual spring water yield (5 39 L/min) emanating from different recharge areas in the mountains of this region. water fluctuations are primarily due to variations in rainfall in recharge area or, more precisely stated, to variations in the amount of rainwater that is able to infiltrate the ground and recharge the groundwater. Marked variations in just following rainfall indicate rapid infiltration of rainwater and recharge of the groundwater in colluvium-related springs, and the curves show strongly periodic seasonal rhythm (Rai et al., 1998). Superimposed on these variations is a periodic (monthly) fluctuation resulting from occasional heavy rainfalls, generally in the rainy season. Following rain, water starts to percolate down through the soil stratum. The recharge of groundwater augments the of springs and seepages, and thus, causes more rapid outflow of groundwater. The high rate of lowers the water table, reduces its gradient, and diminishes the pressure in pore spaces. This transience in recharge and is the cause of the seasonal, local, and short-term fluctuations. In the Indian Himalayan mountains, the great variety in geology and geomorphology, vegetation in recharge areas, land use, biotic interference (i.e., cattle grazing, vegetation harvests for fodder and fuel wood, wildfire, etc.), soil characteristics, and slope and aspect influence the rainfall water partitioning into runoff, interception (vegetation canopy), evapotranspiration and infiltration (Valdiya and Bartarya, 1989; Bisht and Srivastava, 1995; Negi et al., 1998). Therefore, each spring shows different patterns (Negi and Joshi, 1996). Geology, rock type and anthropogenic pollution in the recharge area also are known to profoundly influence water quality of the aquifers (Jenkins et al., 1995; Kumar et al., 1997; Negi et al., 2001; Joshi and Kothyari, 2003). In recent decades, gradual drying up of these springs, low during dry months, and perennial springs becoming seasonal have been reported all across the Himalayan mountains (e.g., Singh and Rawat, 1985, Rai et al., 1998; Singh and Pande, 1989; Valdiya and Bartarya, 1991). Diminished s of springs have been linked to land use and land cover change, biotic interference, and physical alterations (road and building constructions, etc.) in the recharge areas. Impact of afforestation and deforestation on water yields have been reported quite frequently (e.g., Sahin and Hall, 1996; Bruijnzeel, 1989). There is an apprehension that these activities in the fragile Himalayan watersheds have caused soil erosion, depletion in soil organic matter and concomitant loss in water absorption by soil, resulting in losses of water retention capacity of soils (Negi and Joshi, 2002). As a result, the rainwater during monsoon season quickly runs off down slope through natural drainage networks, without much retention in the recharge zones. Therefore, there is a need to understand the rainfall and spring behaviour as influenced by different recharge area characteristics to suggest strategies for long-term water conservation in this region. This study was conducted on six springs emanating from a variety of recharge areas in the western Himalayan mountains in India to understand the relationship between rainfall and spring, and the influence of spring recharge area characteristics on spring. The overall aim of the study was to identify the spring recharge area characteristics controlling water yield to suggest long-term strategies for water resource conservation in this region. Methodology Study area description This study was conducted on six springs in two microwatersheds (small drainage-catchments) located between N and E, and between 1060 and 1980 m above sea level in western Himalaya, India (Fig. 1). The aerial distance between these watersheds is about 5 km, and each of them is approximately 3 km 2. They have northwest aspects. Drainage patterns of these watersheds are dendritic. Morphometry of the watersheds shows that the relief and slope steepness have a marked effect on the rate of surface runoff, infiltration, and stream flow. Geologically the study area lies in the Lesser Himalayan region and constituted by the metasedimentaries of Kumaon Super Group. The area comprises of Pauri phyllite and Khirsu quartzite of Dudhatoli Group. Both the study sites are dominated by thickly bedded jointed/fractured quartzite (50 to 70 m thickness). The strike of the rocks is NW-SE direction in Dugar Gad micro-watershed (site 1), and NWW- SEE direction in Srikot Gad micro-watershed (site 2).

3 Rainfall and Discharge Patterns 21 Figure 1. Location map of the study site and springs. The phyllitic quartzite is alternating with quartzite in the area. At places, thin bands (0.3 to 0.6 m thickness) of dark grey slate are observed in the phyllitic quartzite. Thinly bedded phyllite is fractured and weathered throughout both the sites, while the phyllitic quartzites are jointed, hard, and thickly bedded. Minor structures in these sites were planar (bedding plane/foliation, fractures and joints), which play a ma-

4 22 Negi and Joshi jor role in promoting ground water recharge, movement and location of the spring. There is a strong relationship between tectonic linear and high of springs in this region (Valdiya and Bartarya, 1991). At site 1, the recharge area slopes are covered by colluvial deposits and have main from the in situ rocks. At site 2, the springs are oozing close to the structures (fracture/joint) and the flow is also controlled by these structures. Climate of the study area is temperate (mean annual temperature recorded at 1550 masl = 17.8 C). The mean monthly minimum temperature (3 C; average of four years during study) was recorded in January and the mean monthly maximum temperature (34 C) in May. The rainfall pattern is governed by southwesterly monsoons; two-third of the annual rainfall occurs from mid-june to mid-september. Average annual rainfall difference (coefficient of variation = 21.2%) in the investigated area was recorded from 968 mm to 2551 mm in and , respectively. The average contribution of winter rains (November February) was 15% of the annual rainfall. Most of the rainfall leaves the area as overland flow; little infiltrates to augment groundwater. Evaporation rates vary from 1.1 mm/d (January) to 4.3 mm/d (June), and the average annual pan evaporation is 701 mm. In general, this region is characterized by low evaporative demands. Forests, agriculture and frequently grazed land (by cattle) unsuitable for cultivation are three major land uses in both the watersheds. In site 1, Pinus roxburghii, an evergreen conifer tree, dominates in the vegetation, and in site 2, Quercus incana, anevergreen broadleaf tree, dominates. Trees occupy 9% and 50% of the watershed areas, respectively. Due to sharp variations in geo-ecological conditions, soils of this region are young and thin, with immature soil profiles containing a large amount of rock fragments. Soils are clayey to sandy loam and generally coarse textured. recharge zone characteristics At site 1, the four springs monitored are all fracture/ joint/colluvium-type (hereafter referred to as FR/JT/ COLL). At site 2, two fracture/joint-type springs (FR/JT) were monitored. Recharge area characteristics of these springs varied considerably from one another, with respect to area, slope, land use, vegetation, biotic interference, geology and geomorphology (Table 1). Apparent spring recharge area was delineated through geological and geomorphological surveys of the catchment areas lying above the spring outlet. Recharge areas of the springs ranged from ha, slope from 10 65, and mean elevation from m. Most of the spring recharge areas were under multiple uses and multiple land ownerships, which is quite typical for the region. recharge areas were occupied by low-density forests, Table 1. Recharge area characteristics of the springs selected for study (values in parentheses are elevation masl) Ali b (1440) Bhimli Malli b (1550) Bhimli Talli b (1500) Sainchar b (1460) Srikot c (1210) Barsuri c (1450) Apparent recharge area (ha) Slope/ type Recharge area aspect a land use /SW FR/JT/COLL Moderately grazed pine forest /SE FR/JT/COLL Agricultural land (mostly abandoned)/ low grazed pasture /SE FR/JT/COLL Waste land/moderately grazed pasture /SE FR/JT/COLL Agricultural land (mostly cultivated) /SE FR/JT Agriculture/moderately grazed oak forest Land ownership State Govt. Individuals/ community Community Individuals Individuals/ community /SW FR/JT Oak forest/ scrubs Community Low a SE South East, SW South West, NW North West aspect. b s studied in Dugar Gad micro-watershed (site 1). c s studied in Srikot Gad micro-watershed (site 2). Relative level of biotic interference Moderate Moderate High High High

5 Rainfall and Discharge Patterns 23 agricultural land and pastures with low to high incidence of biotic interference. Data recording At both site 1 and site 2, a non-recording type rain gauge, a pan evaporimeter, and a maximum minimum thermometer were installed at a central location from each of the springs, and data were collected daily. was measured weekly with a stopwatch and a measuring cylinder. Discharge for all the springs were measured for five-years from to hydrological year 1 (1 July 30 June), except for one spring (Sainchar), in which recording began July Throughout this paper, mean values are given for hydrological years. To derive water yield in liter/ month (L/mo), weekly data were averaged to obtain mean water yield per day and multiplied by number of days of the month. The weekly spring data also were converted to liter/minute (L/min). Rainfall amount in spring recharge area was calculated by multiplying the rainfall (received at site 1 and site 2) by the recharge area (ha) of the spring. Rainfall and spring data collected for each of the 6 springs for five hydrological years were averaged for each of the spring, and mean values are used to describe the patterns. Data obtained thus analyzed statistically for regression analysis, t-test and coefficient of variation (Snedecor and Cochran, 1967). Monthly rainfall and spring data across all the five years were put to regression analysis for each of the spring separately and overall correlations (r values) were obtained. Regression analysis was also done for spring and recharge area and slope of the recharge area. A t-test was performed between site 1 and site 2 for mean annual rainfall and coefficient of variation was also calculated for the rainfall across different hydrological years. Results Rainfall characteristics Mean annual rainfall (for a period of five study years) at site 1 and site 2 varies significantly (P < 0.025). 1 In Europe hydrological year covers period between 1 November and 31 October next year. The monsoon season rainfall accounts for 60% of the mean annual rainfall at site 1 (1871 ± 29 mm) and site 2 (1446 ± 307 mm). In general, November and December were dry. Some of the months received unusually low and high rainfall. For example, rainfall at site 2 in August 1995 (1059 mm) was greater than the annual rainfall at this site in (968 mm) and in (976 mm), and it was equal to the annual rainfall of (1050 mm). In 1999, rainfall in August (191 mm) was just equal to that recorded in the usually driest month of February 1996 (192 mm), and far greater than the rainfall in July 1996 (61 mm) and in July 1999 (99 mm) at site 2. In 1996, rainfall occurred both during dry season and monsoon season of the year ( 600 mm) was equal at site 2. Rainfall received in April 1997 (268 mm) at site 1, was equal to that recorded in July 1997 at this site. In 1999, there was no rainfall during April. Rainfall data over five hydrological years indicate that the year which received maximum rainfall at site 1 was a minimum rainfall year at site 2, and vice versa. Rainfall and spring Rainfall and spring s were related closely to each other in all the six springs (Figs. 2(a) 2(f)). Rainfall and spring s were highly correlated (r = for all the FR/JT/COLL springs combined) than the FR/JT springs (r = 0.174). The peak coincided with peak rainfall only in two springs (Figs. 2(a) and 2(d)); in others, the peak occurred one month after peak rainfall. Rainfall in winter had a marginal effect on spring. Recession in the month following the peak was rapid (45 78% decline from peak ) in three FR/JT/COLL springs, but marginal (13 23%) for Ali spring at site 1, and for both the FR/JT springs of site 2. Mean annual was a maximum for Bhimli Malli (8.78 L/min) and a minimum for Srikot (2.87 L/min) (Table 2). The former is an FR/JT/COLL spring with gentle slope and mostly abandoned agricultural land/low grazed pasture with moderate biotic interference in the spring recharge area (Table 1). The latter is a FR/JT spring and had cultivated agricultural land and moderately grazed oak forest with high biotic interference in the sloping recharge area. Mean annual spring expressed as percent of total rainfall in recharge area varied from 0.64% (Bhimli Talli spring; FR/JT/COLL)

6 24 Negi and Joshi Figure 2. springs. Rainfall and spring relationship in (a) Ali, (b) Bhimli Malli, (c) Bhimli Talli, (d) Sainchar, (e) Srikot, and (f) Barsuri Table 2. Minimum and maximum monthly average (across the five hydrological years) water in different springs Minimum (L/min) Month Maximum (L/min) Month Mean annual Water yield (L/1000 L) L/min 10 6 L of rainfall in recharge area FR/JT/COLL Ali 1.71 ± 0.6 May ± 8.7 August 7.04 ± ± Bhimli Malli 6.08 ± 0.6 May ± 6.1 September 8.78 ± ± Bhimli Talli 2.96 ± 0.5 May ± 5.4 September 5.07 ± ± Sainchar 2.11 ± 0.3 May ± 6.0 August 4.97 ± ± Mean (±SE) 3.22 ± ± ± ± ± 7.4 FR/JT Srikot 1.79 ± 0.2 May 5.78 ± 1.2 September 2.87 ± ± Barsuri 3.30 ± 0.5 May 9.74 ± 2.2 September 5.01 ± ± Mean (±SE) 2.54 ± ± ± ± ± 36.4

7 Rainfall and Discharge Patterns 25 Table 3. expressed as percent of rainfall volume in recharge zone of springs in Dugar Gad (mean values for to hydrological years) Month Ali Bhimli Malli Bhimli Talli Sainchar Rainfall % Rainfall % Rainfall % Rainfall % July August September October November December January February March April May June Total/ mean ±SE ±0.26 ±1.06 ±0.18 ±0.58 Table 4. Rainfall volume in the recharge area of springs and spring water yield in Srikot Gad watershed (mean values for to hydrological years) Month Srikot Barsuri Rainfall Rainfall 10 6 L % of rainfall 10 6 L % of rainfall July August September October November December January February March April May June Total/ ± ± 2.59 mean ±SE to 8.51% (Barsuri spring; FR/JT) (Tables 3 and 4). However, a much wider range for spring (0.17% for Bhimli Talli in June and 35% for Barsuri spring in November) across different months for all the springs was recorded. In general, mean annual spring expressed as percent of total rainfall in spring recharge area was recorded maximum during November and December, and minimum during the rainy season (Tables 3 and 4), indicating that a high temperature during the rainy season leads to high evapo-transpiration losses of water. Across the five hydrological years, annual water yield recorded for Bhimli Malli ( L) was the maximum, and for Srikot spring ( L) was the minimum (Tables 5 and 6). But with respect to water yield (expressed in terms of L/1000 L of rainfall in recharge area) the minimum (6.4 L) was recorded for Bhimli Talli spring and the maximum (85.1 L) was recorded for Barsuri spring (Table 2). Thus, each 1000 L (or 1m 3 ) rainfall in spring recharge area yields only 6 85 liter of water as spring, the remaining is either lost as runoff, evapo-transpiration, or deep seepage. Although the mean annual water yield of FR/JT springs (3.94 L/min) was lower than FR/JT/COLL

8 26 Negi and Joshi Table 5. Rainfall and spring at site 1 (values 10 6 L) and proportion of spring to rainfall volume in recharge area (% values in parentheses) Hydrological year Rainfall (mm) Rainfall in spring recharge area Ali Bhimli Malli Bhimli Talli Sainchar Rainfall Rainfall Rainfall water in spring water in spring water in spring yield recharge area yield recharge area yield recharge area water yield (0.48) (1.92) (0.32) (1.40) (2.59) (0.52) (1.78) (0.63) (1.98) (0.34) (1.49) (1.22) (1.56) (0.27) (2.35) (1.00) (1.88) (0.30) (1.76) Mean (0.95) (1.98) (0.35) (1.85) (±SE) (±28.7) (±6.0) (±0.70) (±3.47) (±0.43) (±11.68) (±0.36) (±2.19) (±0.23) (±0.17) (±0.17) (±0.04) (±0.18) Table 6. Rainfall and spring at site 2 (values 10 6 L) and proportion of spring to rainfall volume in recharge area (% values in parentheses) Hydrological Rainfall Rainfall in spring recharge area year (mm) Srikot Barsuri Srikot Barsuri (0.29) 1.50 (1.68) (0.53) 2.31 (6.27) (0.44) 2.93 (4.93) (1.08) 3.63 (10.71) (0.73) 2.81 (8.22) Mean (+SE) (0.61) 2.6 (6.4) (±307) (±61.1) (±10.7) (±0.16)(±0.14) (±0.4)(±1.5) springs (6.47 L/min), the water yield in FR/JT springs per 1000 L of rainfall in spring recharge area was almost double (48.7 vs. 21 L). recharge area characteristics and spring The spring recharge area covered by colluvial deposits in site 1 was the main reason behind the synchronization of rainfall with spring, particularly for Ali and Sainchar springs (Figs. 2(a) and 2(d)). The colluvial deposits consisting of loose soil mass, boulders and other debris allows rapid infiltration of rainwater through it, and the water thus absorbed reappears subsequently from the spring outlet beneath. Therefore, such springs were characterized by low water retention and in them diminishes soon after the rainfall is over. These springs are thus seasonal in nature and yield very low water during the non-rainy season. s originating from hard rocks (FR/JT) take a longer time for rainwater to percolate down and recharge the aquifer. The rainwater thus stored oozes out slowly from the outlet of the springs and the continues for a longer duration. These springs are thus perennial in nature and yield substantial water even during the non-rainy season. The FR/JT springs were thus characterized by greater water retention and sustained yield of water than the FR/JT/COLL springs. Although geology of the spring recharge area was found to be the main controlling factor of the amount and pattern of spring, the spring recharge area characteristics seems to also have influenced the spring. A weak correlation between recharge area (ha) and spring water yield (r = 0.064) indicate that both these parameters are unrelated. For example, Barsuri spring with lowest recharge area (3.5 ha) yield annually Lwater, which is comparable to Bhimli Talli ( L), which has the largest recharge area. A weak inverse relationship (r = 0.12) between slope of the recharge area and spring indicated the negative effect of recharge area slope on spring. For example, Bhimli Malli and Bhimli Talli springs having gentle slopes (10 12 ) had greater wa-

9 Rainfall and Discharge Patterns 27 ter yield compared to springs those have fast slope of the recharge area. Effect of the aspect of the recharge area on spring water yield did not show any trend. water yield per 1000 L of rainfall can be used as a significant measure to determine the efficiency of spring. With respect to this measure Barsuri and Bhimli Malli springs were the best with 85.1 L and 39.3 L per 1000 L of rainfall, respectively. The recharge area of these two springs had least disturbed oak forest/abandoned agricultural terraces and low grazed pasture land. Ali spring, which had a moderately grazed Pine forest despite of large recharge area yield low amount of water relative to rainfall (12 L/1000L). Discussion The two types of springs (FR/JT and FR/JT/COLL) were clearly separable with regard to mean annual water and pattern of water. Although in the FR/JT/COLL springs total water yield was greater, but it was highly fluctuating, and most water was d soon after rains and during the rainless period, the spring diminishes to a great extent. Thus, many of the water supply schemes in this region suffer due to this highly seasonal pattern of the of FR/JT/COLL springs. In the FR/JT springs the water yield was less fluctuating and the decline from peak was only one-third, indicating that they were least dependent on the current season rainfall. Therefore, the FR/JT springs could be best to provide a constant water supply even during rainless periods. Mean annual rate (range = L/min) was far greater than recorded by Rai et al. (1998) in Kumaun Himalaya (range = L/min). In another catchment of this region, spring recorded by Valdiya and Bartarya (1991) was quite high (range = 5 L/min in a colluvial spring to 282 L/min in fluvial deposit-related spring). Valdiya and Bartarya (1991) studied a number of springs of different geology in Gaula catchment (central Himalaya) and the mean annual spring water yield recorded for an FR/JT spring (33.2 L/min) was about two times higher than a colluvial-type spring. In the eastern Himalaya, Rai et al. (1998) recorded water yield rates ranging from L/min, with a decline in flow in seasonal springs with the progression of time during a three-year study period. The in perennial springs did not decline over the study period. In this region diminished flow of springs during non-rainy season is the major challenge for the Government to cater to the demand for household water consumption. Therefore, an understanding of the relationship between spring and recharge area characteristics can be of enough applied value with regard to long-term water conservation strategies in this region where people depend upon springs for fresh water. A larger recharge area may not be favourable for spring, as it will place more demand of water on the soil moisture in terms of evapo-transpiration. Smaller recharge area may likely be easy to protect against biotic interference, and bring desiredchangesinlanduseandlandcover(cf.negi and Joshi, 2002). Besides geology, land use and level of biotic interference emerged as one of the controlling factors for the spring. It can be pointed out that oak forest, abandoned crop field terraces, moderately grazed pasture land and low biotic interference in the spring recharge area are conducive for spring water yield. Oak forests are regarded for their soil and water conservation function in this region due to thick litter layer, rich ground vegetation and spongy forest floor, which allows more infiltration of rain water to soil stratum than the pine forests (Singh and Pande, 1989). Pine forests are accused for exploitation of soil moisture due to fast growth and shallow root system, which feed on surface water received through rainfall. Conclusions In the western Himalayan mountains in India, the steep and irregular topography with its great diversity in hydrometeorology, geology, land use and land ownership create a variety of spring recharge areas in which altitude, slope, aspect, water contributing area, vegetation, biotic interference, etc. all vary. Interplay of all these factors affects the water yield and nature (perennial or seasonal) of the springs. Our study on 6 springs in two micro-watersheds of the western Himalaya indicate that FR/JT springs could be suitable for tapping water for household consumption as these are less affected by rainfall than the FR/JT/COLL springs. However, water quality of these two types of springs needs further investigation for definite conclusion. The recharge area characteristics such as,

10 28 Negi and Joshi smaller size, abandoned agricultural terraces with a dense growth of bushes but few trees, oak forest, and minimal grazing and low biotic interference are factors those promote the rain water retention. Therefore, these spring recharge area characteristics should be maintained and promoted for long-term water resource conservation in this region. Acknowledgements This work was carried out under Land and Water Resource Management Core Programme of our Institute. We thank to the Core Head, LWRM and the Director of the Institute for facilities and scientific inputs. Thanks are due to two anonymous referees who made useful suggestions to improve this manuscript. References Bisht, N.S. and Srivastava, A.C.: 1995, Sustainable Management and Conservation of Drinking Water Sources in Himalaya, Indian Forester 7, Bruijnzeel, L.A.: 1989, (De)forestation and Dry Season Flow in the Tropics: A Closer Look, J. Trop. For. Sci. 1(3), Jenkins, A., Sloan, W.T. and Cosby, B.J.: 1995, Stream Chemistry in the Hills and High Mountains of the Himalayas, Nepal, J. Hydrol. 166, Joshi, B.K. and Kothyari, B.P.: 2003, Chemistry of Perennial s of Bhteagad Watershed: A Case Study from Central Himalayas, India, Environm. Geol. 44, Kumar, K., Rawat, D.S. and Joshi, R.: 1997, Chemistry of Water in Almora, Central Himalaya, India, Environm. Geol. 31(3/4), Negi, G.C.S. and Joshi, V.: 1996, Geohydrology of s in a Mountain Watershed: The Need for Problem Solving Research, Curr. Sci. 71(10), Negi, G.C.S., Rikhari, H.C. and Garkoti, S.C.: 1998, The Hydrology of Three High-Altitude Forests in Central Himalaya, India: A Reconnaissance Study, Hydrol. Processes 12, Negi, G.C.S., Kumar, K., Panda, Y.S. and Satyal, G.S.: 2001, Water Yield and Water Quality of some Aquifers in the Himalaya, Int. J. Ecol. and Environm. Sci. 27, Negi, G.C.S. and Joshi, V.: 2002, Drinking Water Issues and Development of Sanctuaries in a Mountain Watershed in the Indian Himalaya, Mountain Res. Dev. 22(1), Rai, R.N., Singh, K.A. and Solanki, R.C.: 1998, A Case Study of Water Flows of Some Hill s of Sikkim, Indian J. Soil Cons. 16(1), Rai, S.P., Valdiya, K.S. and Rawat, J.S.: 1998, Management of Water Resources: Sanctuaries, in K.S. Valdiya (ed.), The Khulgad Project: An Experiment in Sustainable Development, Gyanodaya Prakashan, Nainital, India, pp Sahin, V. and Hall, M.J.: 1996, The Effects of Afforestation and Deforestation on Water Yields, J. Hydrol. 178, Singh, A.K. and Pande, R.K.: 1989, Changes in the Activity: Experiences of Kumaun Himalaya, India, The Environmentalist 9(1), Singh, A.K. and Rawat, D.S.: 1985, Depletion of Oak Forests Threatening s: An Exploratory Study, The National Geog. J. India 31(1), Snedecor, G.W. and Cochran, W.G.: 1967, Statistical Methods, Oxford University Press and IBH Publishing Co., New Delhi, 507 pp. Valdiya, K.S. and Bartarya, S.K.: 1989, Diminishing Discharges of Mountain s in a Part of Kumaun Himalaya, Current Science 58(8), Valdiya, K.S. and Bartarya, S.K.: 1991, Hydrological Studies of s in the Catchment of the Gaula River, Kumaun Lesser Himalaya, India, Mountain Res. and Dev. 11(3),