Kaligandaki River Basin Research Articles

Evaluation of Satellite-Derived Precipitation Products for Streamflow Simulation of a Mountainous Himalayan Watershed: A Study of Myagdi Khola in Kali Gandaki Basin, Nepal

This study assesses four Satellite-derived Precipitation Products (SPPs) that are corrected and validated against gauge data such as Soil Moisture to Rain—Advanced SCATterometer V1.5 (SM2RAIN-ASCAT), Multi-Source Weighted-Ensemble Precipitation V2.8 (MSWEP), Global Precipitation Measurement Integrated Multi-satellitE Retrievals for GPM Final run V6 (GPM IMERGF), and Climate Hazards Group InfraRed Precipitation with Station (CHIRPS). We evaluate the performance of these SPPs in Nepal’s Myagdi Khola watershed, located in the Kali Gandaki River basin, for the period 2009–2019. The SPPs are evaluated by validating the gridded precipitation products using the hydrological model, Soil and Water Assessment Tool (SWAT). The results of this study show that the SM2RAIN-ASCAT and GPM IMERGF performed better than MSWEP and CHIRPS in accurately simulating daily and monthly streamflow. GPM IMERGF and SM2RAIN-ASCAT are found to be the better-performing models, with higher NSE values (0.63 and 0.61, respectively) compared with CHIRPS and MSWEP (0.45 and 0.41, respectively) after calibrating the model with monthly data. Moreover, SM2RAIN-ASCAT demonstrated the best performance in simulating daily and monthly streamflow, with NSE values of 0.57 and 0.63, respectively, after validation. This study’s findings support the use of satellite-derived precipitation datasets as inputs for hydrological models to address the hydrological complexities of mountainous watersheds.

Effect of Surface Characteristics and Rainfall in Infiltration Rate: A Case Study of Kaligandaki River Basin

Study of infiltration characteristics is crucial for effective watershed management, as it helps determine the water availability for crops, the need of irrigation, groundwater recharge, and surface runoff. This study is aimed at identifying the relation between infiltration rate and surface characteristics as well as rainfall rate in the Kaligandaki River basin of Nepal using Hydrologic Modelling System (HEC-HMS). HEC-HMS is a physically based, semi-distributed model that uses the weather and spatial information of soil and landuse of the basin for deriving the inputs for the model. A hydrological rainfall-runoff model is developed for the Kaligandaki River basin, with outlet at hydrological station 420, Kotgau, of Department of Hydrology and Meteorology (DHM). The model was then validated at DHM station 420, Angsing, of Kaligandaki River. Model generated subbasin wise infiltration rates and existing landuse were analysed and it was found that sub-basins with dominant landuse as forest had high infiltration rate among prevailing landuse types. Conversely, low infiltration rate was observed for barren area, snow/glacier and grassland landcover type dominated subbasins. A positive correlation among rainfall rate and infiltration rate was seen with linear increase in infiltration rate for an exponential increase of average rainfall intensity. Infiltration rate was found to have positive correlation with the Hydrologic Soil Group types as suggested by NRCS. Moreover, the study signified a greater impact of landcover over soil types on infiltration rates. Whereas, no significant impact of basin slope on infiltration rate could be identified, which may be due to preclusion of multiple topographic features. Understanding the impacts of rainfall intensity and surface characteristics on infiltration enables proactive measures to mitigate the issues like landslide and reduce flooding and soil erosion by improving infiltration rates through surface condition assessment.

Detectability of the trend and hysteresis in rainfall across Kali Gandaki River Basin, Central Himalaya, Nepal

Detectability of the trend and hysteresis in rainfall across Kali Gandaki River Basin, Central Himalaya, Nepal

Feeding ecology of Assamese macaques (Macaca assamensis) troops in Kaligandaki and Budhigandaki River basins of central Nepal

Abstract. Ghimire SC, Khanal L, Chalise MK. 2021. Feeding ecology of Assamese macaques (Macaca assamensis) troops in Kaligandaki and Budhigandaki River basins of central Nepal. Biodiversitas 22: 2625-2634. Seasonal fluctuations in the availability of key food resources impact the foraging behavior of animals. This study aimed to examine the seasonal variations in feeding time of Assamese macaques (Macaca assamensis) in the sub-tropical deciduous riverine forest environment of central Nepal. Two troops of Nepal population of Assamese macaques, a troop from Kaligandaki River Basin (KRBT) and the next from Budhigandaki River Basin (BRBT) were studied by focal animal sampling method. Data from systematic behavioral observations were analyzed with reference to that of the vegetation surveys. Assamese macaques invested more than two-fifths (>40%) of the diurnal time on feeding. The KRBT consumed 71 plant species and the BRBT relied on 69 food plants. Leaves, mature and young, constituted the most dominant food item followed by the fruits and seeds. The two study troops inhabiting highly similar habitats of food plants (Sorensen’s Similarity Index = 0.93) didn’t have a significant difference in the selection of food-plant parts. However, the remarkable temporal difference in feeding plant parts was observed in concordance with their seasonal availability. Young leaves, when available during the spring and pre-monsoon were the major food items. Contrastingly, mature leaves were the food items during the winter on which animals were forced to rely when young leaves were scarce. We conclude that food choice and time investment on the feeding of different plant parts differ depending on the availability of food in the area. Macaques living in comparable habitats with similar food plants have analogous food choices and time investments.

Insights on the Impacts of Hydroclimatic Extremes and Anthropogenic Activities on Sediment Yield of a River Basin

Streamflow and sediment flux variations in a mountain river basin directly affect the downstream biodiversity and ecological processes. Precipitation is expected to be one of the main drivers of these variations in the Himalayas. However, such relations have not been explored for the mountain river basin, Nepal. This paper explores the variation in streamflow and sediment flux from 2006 to 2019 in central Nepal’s Kali Gandaki River basin and correlates them to precipitation indices computed from 77 stations across the basin. Nine precipitation indices and four other ratio-based indices are used for comparison. Percentage contributions of maximum 1-day, consecutive 3-day, 5-day and 7-day precipitation to the annual precipitation provide information on the severity of precipitation extremeness. We found that maximum suspended sediment concentration had a significant positive correlation with the maximum consecutive 3-day precipitation. In contrast, average suspended sediment concentration had significant positive correlations with all ratio-based precipitation indices. The existing sediment erosion trend, driven by the amount, intensity, and frequency of extreme precipitation, demands urgency in sediment source management on the Nepal Himalaya’s mountain slopes. The increment in extreme sediment transports partially resulted from anthropogenic interventions, especially landslides triggered by poorly-constructed roads, and the changing nature of extreme precipitation driven by climate variability.

Elevational pattern and seasonality of avian diversity in Kaligandaki River Basin, central Himalaya

This study explored bird diversity, seasonal variation, and associated factors along an elevational gradient in an important biodiversity area (IBA) of central Nepal: the Kaligandaki River basin of Annapurna Conservation Area. The field survey was carried out in 2019 over two seasons, winter (January and February) and summer (May and June) using the point count method. A total of 90 sampling plots were set up from elevations of 800m (Beni) to 3,800m (Muktinath). Data for variables including the number of fruiting trees (indicator of resource availability) and distance to the road (indicator of disturbance) were collected, and their influence on avian diversity were assessed. The results revealed a diverse assemblage of avian fauna in the study area with consistent species richness over the two seasons. A decline in species richness and diversity with increasing elevation was observed. Of the different habitat types within the study area, forest and shrubland habitats showed the strongest association with bird species distribution and richness. We emphasize the need for long-term monitoring programs with standardized sampling approaches to better understand the avifauna in the central Himalaya.

Crop Raiding Status by Assamese Monkeys (Macaca assamensis) along the Kaligandaki River, Western Nepal

A study on Assamese monkeys (Macaca assamensis) in Kaligandaki river basin at Ramdi of Palpa and Syangja districts of western Nepal was performed. The field study was conducted from February 2015 to January 2016 spending 1804 hours to explore the ecology and feeding behavior of Assamese macaque. The study mainly focused the Ramdi village area. A total of 24 individuals of Assamese monkeys were counted towards Palpa district and 18 individuals were counted towards Syangja district. Crop raiding status was examined each year by questionnaire survey method for local household villagers as well as direct observation by the researcher. It was found that maize (47.14 %) was the highest raided among the crops, followed by fruits (16.43 %), wheat (11.13 %), millet (5.72 %), rice (4.58 %), potato (4.27 %), lentil (4.07 %), mustard (1.26 %), pumpkin (1.14 %), bread (0.96 %), brown lentil (0.81 %), broad beans (0.80 %), sesame (0.60 %), black pulses (0.35 %), dal (0.20 %), cauliflower (0.14 %), tomato (0.1 %), egg (0.1 %), samosa (0.1 %) and gram (0.1%).

Learning to cope with water variability through participatory monitoring: The case study of the Mountainous region, Nepal

Participatory monitoring allows communities to understand the use and management of local water resources and at the same time develop a sense of ownership of environmental information. The data generated through participatory monitoring of stream flow and rainfall generate evidences to corroborate local people’s experiences with changing water resources patterns. In this study we evaluate the potential of participatory monitoring of hydrological variables to improve scarce water supply utilization in agriculture. The case study site is the Mustang district in Nepal, which is located in the Upper Kaligandaki River Basin in the Himalayas with unique and complex geographical and climatic features. This region is characterized by a semi-arid climate with total annual precipitation of less than 300 mm. Water supply, agricultural land, and livestock grazing are the key ecosystem services that underpin livelihood security of the local population, particularly socio-economically vulnerable groups. An analysis of the measured stream flow data indicate that annual flow of water in the stream can meet the current crop irrigation water needs for the agricultural land of the research site. The data provide local farmers a new way of understanding local water needs. Participatory monitoring would contribute to an optimization of the use of ecosystem services to support economic development and livelihood improvement.

Hydraulic Parameters for Sediment Transport and Prediction of Suspended Sediment for Kali Gandaki River Basin, Himalaya, Nepal

Sediment yield is a complex phenomenon of weathering, land sliding, and glacial and fluvial erosion. It is highly dependent on the catchment area, topography, slope of the catchment terrain, rainfall, temperature, and soil characteristics. This study was designed to evaluate the key hydraulic parameters of sediment transport for Kali Gandaki River at Setibeni, Syangja, located about 5 km upstream from a hydropower dam. Key parameters, including the bed shear stress (τb), specific stream power (ω), and flow velocity (v) associated with the maximum boulder size transport, were determined throughout the years, 2003 to 2011, by using a derived lower boundary equation. Clockwise hysteresis loops of the average hysteresis index of +1.59 were developed and an average of 40.904 ± 12.453 Megatons (Mt) suspended sediment have been transported annually from the higher Himalayas to the hydropower reservoir. Artificial neural networks (ANNs) were used to predict the daily suspended sediment rate and annual sediment load as 35.190 ± 7.018 Mt, which was satisfactory compared to the multiple linear regression, nonlinear multiple regression, general power model, and log transform models, including the sediment rating curve. Performance indicators were used to compare these models and satisfactory fittings were observed in ANNs. The root mean square error (RMSE) of 1982 kg s−1, percent bias (PBIAS) of +14.26, RMSE-observations standard deviation ratio (RSR) of 0.55, coefficient of determination (R2) of 0.71, and Nash–Sutcliffe efficiency (NSE) of +0.70 revealed that the ANNs’ model performed satisfactorily among all the proposed models.

Improving water resources management using participatory monitoring in a remote mountainous region of Nepal

Study RegionWe interrogate the water resources of the Upper Kaligandaki River Basin (UKGRB), in the remote Mustang District of northwestern Nepal. The Nepal Himalayas are a major reservoir of freshwater; yet the impediments to its exploitation by local inhabitants are manifold, including weak governance structures, steep and irregular terrain, and frequent natural hazards that are linked to climate change. The UKGRB is characterised by its extreme fragility, paucity of water and water-related data, and enormous variability of the effects of climate change on glaciers through time and space. Study FocusThe purpose of this paper is to elucidate catchment hydrology and local flow variability, before demonstrating the ways in which sustainable water resource management (WRM) can be achieved regionally. New Hydrological Insights for the RegionWe present the local crop water balance, and suggest methods to reduce crop water requirements and to ensure a more equitable distribution of available seasonal flow. We also propose a series of long-term changes that are needed to secure sustainability. Then, we suggest that the principles of citizen science can help to improve the spatial coverage of data, generating new hydrological time series (e.g. river discharge), which can aid local decision makers in the WRM realm (e.g. irrigation scheduling). This approach has the potential to be scaled-up across the entire UKGRB (and, indeed, Nepal as a whole).

Estimation of Hydrologic Alteration in Kaligandaki River Using Representative Hydrologic Indices

Anthropogenic activities have led to the transformation of river basins and natural flow alteration around the world. Alteration in flow regimes have adverse effects on river ecosystems. Flow value changes signify the alteration extent and a number of flow related indices can be used to assess the extent of alteration in a river ecosystem. Selection of a few and ecologically relevant indices from a large set of available indices is a daunting task. Principal Component Analysis helps to reduce these large indices to a few ecologically significant indices and removes statistical redundancy of data to give uncorrelated data sets. These representative indices are useful in the primary investigation of a less studied area like the Kaligandaki River basin, Nepal. This paper uses reduced indices from the Kaligandaki River to calculate the alteration on the river section downstream of a hydropower facility using the Histogram Comparison Approach (HCA) combined with Hydrologic Year Types (HYT). The combined approach eliminates the potential underestimation of alteration values which may occur due to the exemption of hydrologic year types from the analysis, a feature equally relevant in river ecology. A new metric is used for the calculation of combined alteration using HCA-HYT in this paper. The analysis showed 60.71 percent alteration in the natural flow regime in the area past a hydropower construction, which is classified in the high alteration category. The study can be a guide for further analysis of the ecological flow management of a river section and a parsimonious approach to other areas where hydrological data is limited to historical flow records only.

Population status and distribution of Assamese macaques (Macaca assamensis) in Kaligandaki river basin of Baglung and Parbat districts, Nepal

Population status and distribution of Assamese monkey in Kaligandaki river basin was studied by direct count method and block design. Field research was conducted from November, 2015 to June, 2016.The total area of 104.70 km2 was surveyed to determine the Population status and distribution pattern of Assamese monkey. Total of 47 Assamesemacaques were counted in four different troops. The group density was found to be 0.038groups/km2 with a population density of 0.44 individuals/km2 and a mean group size of11.75 (range 3-16) individuals. Age sex composition of macaque comprised 23.40% adult males, 19.14% adult females followed by 17.02% sub adult male, 19.14% young adult female, 14.8% juveniles and 6.38% infants. Adult sex ratio was observed 1:0.81 i.e. 122males per 100 females and the recruitment rate was found 0.33. i.e. 33 infants per 100females. The distribution pattern of Assamese macaques among four different study blocks was found clumped distribution in the study area. There was significant difference in distribution of Assamese macaques among four different blocks (χ2 =6.2996 ,d.f.= 3,p= 0.09791, p>0.05).

Impacts of Climate change on Hydropower Potential in Kaligandaki River Basin -A Case Study of Kaligandaki Gorge Hydropower Project, North of Nepal

Impacts of Climate change on Hydropower Potential in Kaligandaki River Basin -A Case Study of Kaligandaki Gorge Hydropower Project, North of Nepal

Impacts of Climate change on Hydropower Potential in Kaligandaki River Basin -A Case Study of Kaligandaki Gorge Hydropower Project, North of Nepal

Nepal has a considerable hydropower potentiality, however the analysis of Kaligandaki River Basin optimization of power potentiality and subsequently identified two critical impacts of climate change-GLOF’s and variability of runoff along with temperature difference are most pronounced during the dry winter season, and least during the height of the monsoon. In Himalaya region the Intergovernmental Panel on Climate Change (IPCC) has indicated that global warming is occurring relatively faster in recent decades, with the rate of temperature increase being greater in the high altitude Himalaya, then lowland parts of Nepal [1].

GENERAL BEHAVIOR AND VEGETATION ASSOCIATED WITH THE HABITATS OF ASSAMESE MONKEY (Macaca assamensis McClelland, 1840) ALONG KALIGANDAKI RIVER BANK, WESTERN NEPAL

This study was focused on Macaca assamensis general behavior and vegetation associated with their habitats in Kaligandaki River Basin at Baglung and Parbat Districts of Nepal. The field survey was conducted from December, 2015 to May, 2016 to explore the Assamese Macaque general behavior and vegetation associated with their habitats. Total area of 104.70 km2 was surveyed, vegetation analysis was done by random quadrates sampling method and behavioral data were collected by scan sampling method. A total of 47 individuals of Assamese Macaques (Macaca assamensis) were counted in four different troops. Total of 2240 scan samples were recorded from the four different troops during this study period the scan samples revealed that foraging was 47%, moving 28%, resting 14% and grooming 11%. In the context of daily activity pattern for aging time of Assamese monkey was found to be highest 54% in 15:00 to 18:00 observational phase and lowest 40% in the observational phase of 12.00 to 15.00 hours. Moving time of the Assamese monkey was found to be highest 33% in 12.00 to 15.00 observational phase and lowest 22% at 15:00 to 18:00 observational phase, resting time of Assamese monkey was found to be highest 15% in 09:00 to 12:00 hours and lowest 13% in 15:00 to 18:00 observational phase and Assamese monkey were seen mostly grooming 13% in 12.00 to 15.00 hours and lowest 10% in 15:00 to 18:00 observational phase. By quadrate sampling, 58 plant species with 716 number were recorded. Sal (Sorea robusta) was the dominant plant species with relative density 31.42% and relative frequency 8.376% which was followed by Tiju (Diospyros malabarica)with relative density 10.93% and relative frequency 8.376%.Journal of Institute of Science and TechnologyVolume 22, Issue 1, July 2017, page: 110-119

Bias correction of climate models for hydrological modelling – are simple methods still useful?

ABSTRACTThe spatial climatic characteristics of the Himalayas are complex and a challenge for regional climate models (RCMs). There is no doubt that some form of correction before any application of RCM simulations is a must. In recent years, simple bias correction techniques have been overshadowed by more popular and complex bias correction techniques. In this study an attempt is made to compare the performance of a simple and of a comparatively complex correction technique for hydrological analysis at a monthly resolution in the Kaligandaki River Basin of Nepal. The research workflow consists of bias correction of temperature and precipitation using a simple technique (linear scaling) and a comparatively complex one (quantile mapping). The performance at monthly resolution is evaluated against observed meteorological data while a combined evaluation is made via hydrological model response analysis. The wetter and colder RCM estimates were significantly improved after bias correction. The hydrological modelling response also shows the importance of the bias correction of the RCMs. However, no significant difference was observed between the outputs of linear scaling and quantile mapping which exhibited almost identical performances. Hence, this study has a novel conclusion that a simple method, such as linear scaling, is sufficient for hydrological analysis at monthly resolution.

Conflict due to Assamese Macaques (Macaca assamensis McClelland 1840) and crop protection strategies in Kali-gandaki River Basin, Western Nepal

This study was conducted on conflict due to Assamese Macaques (Macaca assamensis McClelland 1840) and crop protection strategies in Kaligandaki river basin, Baglung and Parbat Districts, Western Nepal. Field survey was conducted from 25 October to 22 December, 2015. Questionnaire survey was carried out to estimate the crop protection strategies and crop damaged by the macaque with the local inhabitants in the Kaligandaki River Basin VDCs. Stratified random sampling method was used to select respondent for the questionnaire survey. Out of 654 river basin households, 92 respondents were selected as sample size from the study area. Maize was the highest raided crop 46.95% followed by 15.91% paddy, 15.11% potato, 10.84% millet, 6.88% wheat, 2.05% pulses, 1.59% fruits and 0.66% vegetables. The most commenly used crop protection strategy in guarding their field were by constant vigilance 50%, 25% of field owners use “Scarecrows” 20% used dogs, 5% farmers used tin-box and catapult to chase the macaques from the crop fields. This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Study on Climate Change Induced Precipitation Variability and Its Impact on High Mountains of Nepal (A Case Study of - Kaligandaki River Basin, North of Nepal)

The goal of this study is to develop different scenarios of water resource availability in near upstream of Kaligandaki River basin, under climate change-induced parameters such as precipitation and temperatures variability, considering a potential doubling of the atmospheric CO2 concentration in the next 100 years. Climate models suggest that global warming could bring warmer, drier conditions to Nepalese high Mountains due to the large topographical differences of the climate parameters. Although precipitation increases are projected by some models, on the glaciers of the Nepalese high Mountains, a detailed knowledge of mass-balance observation and discharge measurement are considered and the combination of both will be analyzed by means of either Water Balance Model (WatBal) or General Climate Model (GCM) with multi criteria model performance evaluation. To obtain reasonable and ensemble result, the discharge measurements should be taken during the melting season which demonstrates that timing of runoff. In most cases, the Water Balance Model CLIRUN3 was combined with 20 years of basic climate information records (precipitation, potential evapotranspiration and water flow) to simulate monthly river runoff in the river basin. Ultimately the flow of river is part of the watershed while the others belong to forest lands. The model will be calibrated and run for both watersheds under scenarios with temperature increments of +1 and +2°C, while the precipitation changes considered were ±15% for the locality and ±20% for the overall river basin. It was observed that the monthly runoff tends to considerable decrease of the mean value in the watersheds when temperature increases and precipitation decreases. If both temperature and precipitation increase, the mean runoff value in the region will be reduced by considerable amount as 5 to 35% from monsoon to non-monsoon season. In the basin of the locality, this will also cause to potential evaporation. Thus, soil moisture and water availability may decrease over much of Kaligandaki river basin with serious consequences for rained and irrigated agriculture, urban and water supplies, hydropower and ecosystems. However, the assessment of global warming impacts on locality is an uncertain task because the projections of different models vary widely, particularly for precipitation, and because it performs poorly in reproducing the observed climate condition of Kaliganadaki. At the end, this will help to formulate numerical flow line glacier model on high Mountains of Nepal at upstream of Kaligandaki river, also this paper concludes with a brief discussion of some other areas of uncertainty in the hydrological modeling of Kaligandaki River flows and possible alternative, external forcing mechanisms for flows in the next few decades.

An artificial neural network-based snow cover predictive modeling in the higher Himalayas

With trends indicating increase in temperature and decrease in winter precipitation, a significant negative trend in snow-covered areas has been identified in the last decade in the Himalayas. This requires a quantitative analysis of the snow cover in the higher Himalayas. In this study, a nonlinear autoregressive exogenous model, an artificial neural network (ANN), was deployed to predict the snow cover in the Kaligandaki river basin for the next 30 years. Observed climatic data, and snow covered area was used to train and test the model that captures the gross features of snow under the current climate scenario. The range of the likely effects of climate change on seasonal snow was assessed in the Himalayas using downscaled temperature and precipitation change projection from — HadCM3, a global circulation model to project future climate scenario, under the A1B emission scenario, which describes a future world of very rapid economic growth with balance use between fossil and non-fossil energy sources. The results show that there is a reduction of 9% to 46% of snow cover in different elevation zones during the considered time period, i.e., 2011 to 2040. The 4700 m to 5200 m elevation zone is the most affected area and the area higher than 5200 m is the least affected. Overall, however, it is clear from the analysis that seasonal snow in the Kaligandaki basin is likely to be subject to substantial changes due to the impact of climate change.

Assessing suitability of apple cultivation under climate change in mountainous regions of western Nepal

Mustang, a mountainous region in the Kali Gandaki River Basin in western Nepal, has been increasingly experiencing climatic changes (e.g., higher temperatures). Rising temperatures lead to ecological shifts, which, in turn, can lead to the expansion of the lower limit for the cultivation of apple trees in this area. Apple cultivation can provide opportunities for adaptations under climate change through vulnerability reduction, income source diversification, livelihood improvement, and capacity building for farmers. As there is a lack of a strong basis to justify the expansion of apple cultivation in Mustang, this study examines the biophysical and socioeconomic suitability of apple cultivation in the area. Necessary data and information were collected from both primary and secondary sources. Findings of biophysical suitability using variable and equal weights to the indicators showed that 5.2 and 4.1 % of the areas are highly suitable for apple cultivation, respectively. However, not all potential farming areas are currently in use. Thus, there is the possibility to expand apple cultivation into unplanted areas and to integrate apple crops with other crops on cultivated lands. Increasing temperature may increase the suitable areas for the cultivation of apples in the coming years. High, benefit–cost ratio for land use confirmed the economic suitability of apple farming when compared to other land uses. The social suitability assessment showed no social discords, conflicts, or disagreements with apple cultivation, which is a positive indicator for the expansion of apple cultivation in western Nepal.