Search

Seasonal and annual water supplies of the rivers originating in the Hindukush-Karakoram-Himalaya (HKH) region of Pakistan are important to manage the Indus basin irrigation system for better agricultural production and its dependent agrarian economy. In this study, we simulated the current and future snowmelt runoff in a poorly gauged river basin of the Hindukush region under Representative Concentration Pathways (RCP) climate change scenarios. Snowmelt Runoff Model (SRM) furnished with satellite snow cover maps and hydro-meteorological data were used to simulate the daily river discharge for the period 2000‒2005. The results indicated that SRM has effectually simulated the runoff in Chitral River with Nash-Sutcliffe model efficiency coefficient of 0.85 (0.84) and 0.88 (0.83) in the basin-wide (zone-wise) application during the calibration and validation periods, respectively. The results obtained under future climate change scenario showed ∼14‒19% increase in mean summer discharge under three mid-21st century RCP (2.6, 4.5 and 8.5) scenarios. While an increase of ∼13‒37% is expected under late-21st century RCP scenarios. This study can help water resource managers to plan and manage peak discharges from the Chitral River Basin in the future and can thus prevent major losses due to floods in the area. [ABSTRACT FROM AUTHOR]

The expanded demands of marble oriented products represent a likely threat to nature and natural resources. Practically half of the marble material is disposed of at the very initial stage in the form of irregular stone scrap followed by discharge of slurry during the processing. The produced slurry adversely influences water assets and causing an exceptional economic and environmental loss. The explored territory of Mohamand marble zone, Khyber Pakhtunkhwa, has in excess of 150 Marble Processing Units dissipated alongside the main water asset, Subhan Kharh, an occasional stream. The stream water straightforwardly joins the River Kabul having its own economic, recreational, social, aesthetic, and natural commitment in Pakistan's geography. During industrial discharge and rainy seasons, the carbonated waste makes its way into the nearby stream making the water unsuitable for domestic use. This paper provides the physio-chemical status of the water samples collected from various marble processing units, selected randomly, in the area. In addition, the waste generated in the form of slurry by each marble processing unit on a daily (1.65 m3 ), monthly (50.25 m3 ), and annual ( 603 m3 ) basis is part of the paper. The marble powder ratio in the slurry was estimated at 15.25 Kg, 457.50 Kg, and 5490.55 Kg on a daily, monthly, and yearly basis respectively. The article likewise proposes reusing alternatives of wastewater and auxiliary utilization of the marble powder collected from the slurry. Hence, the substitute utilization of waste powder as building, construction, and landfilling material would be gainful and the unfavorable effects on the environment would be diminished. [ABSTRACT FROM AUTHOR]

In many parts of the world, including the Hindukush-Karakoram-Himalayan (HKH) region, the population depends on snow and glaciers-melt waters to grow food, generate electricity and store water for their use throughout the year. The annual and seasonal variation in the snow cover area (SCA) due to its response to the climatic variables directly influences the water supplies. The aim of current study is to evaluate the spatio-temporal trends in the annual and seasonal snow cover at basin-wide scale. Impact of topography on the SCA is analyzed by revealing the trends in SCA in different elevation bands. It also investigates the trends in hydro-climatic factors (temperature, precipitation and river flows) in the Chitral River basin (Hindukush region) and their linkage to the SCA variations. Snow cover is estimated using cloud-free 8-day MODIS snow products on 17-year time-period (2000–2016). Hydro-climatic data of the river flow (1989–2014), temperature, and precipitation (1965–2013) were obtained from Water and Power Development Authority (WAPDA), and Pakistan Meteorological Department (PMD). Trend analysis of the SCA and hydro-climatic variables was carried out using Mann-Kendall's trend test and Sen's slope. The results reveal: (1) a significant increasing trend in the SCA at basin-wide scale and at all elevation zones i.e. A to E (1471–7708 m ASL), except zone B (2500–3500 m ASL), (2) decreasing and constant trends in the mean temperature and total precipitation, respectively, over the same time-period as SCA indicating possible reasons for increasing SCA, (3) a slight decrease in the mean annual and summer flow (1989–2014) possibly due to the summer cooling, reduced snowmelt and slightly decreasing summer precipitation over this time-period, and (4) strong dependency of the Chitral River flow on snowmelt, driven by the temperature seasonality. Modeling snowmelt runoff under future climate projections in the study area may help to manage the water resources properly. [ABSTRACT FROM AUTHOR]

Iodine is an essential microelement required by humans and animals. Leaching of soils under intensive rains has threatened the fertility status of iodine in soils. Therefore, four discrete amendments were used for the mitigation of iodine leaching from soils. For this study, soils collected from four land uses were mixed with the amendments (gypsum, lime, fly ash, charcoal and sawdust) at the rate of 0, 2.5% and 5% (w/w) in PVC columns. Potassium iodide (KI) was applied to the soil at rate of 100 mg kg-1 and 200mg kg-1. Iodine was determined in water after three leaching events. Results indicated that soil of each land use had apparently influenced the leachability of iodine. Lower amount of iodine was released from the barren and pasture soils as compared to the soils of agriculture and forest land uses. Application of amendments significantly reduced the leaching of iodine from soil. Application of KI increased iodine concentration in the leachate. Across all soils, reduction of iodine leaching or retention of iodine among soil amendments varied in the order charcoal > sawdust > fly ash > gypsum > lime. Overall charcoal and sawdust efficiently reduced iodine leaching than other three amendments. The pH values of the leachate were oppositely associated with the iodine retention of soil. Iodine concentrations in soils were related to the amount of soil organic matter. This study has shown that the retention of iodine in soils could potentially be ameliorated by a suitable soil amendment [ABSTRACT FROM AUTHOR]

Pakistan is an agriculture-based economy and major proportion of irrigation water for its cultivated lands is abstracted from the Upper Indus Basin (UIB). UIB water supplies are mostly contributed from the high-altitude snow and glacier fields situated in the Hindukush–Karakoram–Himalayan ranges. Any change in the flows of these river catchments due to climate variability may result in the form of catastrophic events like floods and droughts and hence will adversely affect the economy of Pakistan. This study aims to simulate snowmelt runoff in a mountainous sub-catchment (Shyok River basin) of the UIB under climate change scenarios. Snowmelt Runoff Model (SRM) coupled with remotely sensed snow cover product (MOD10A2) is used to simulate the snowmelt runoff under current and future climate scenarios in the study area. The results indicate that (a) SRM has efficiently simulated the flow in Shyok River with average Nash–Sutcliff coefficient value (R2) of 0.8 (0.63–0.93) for all six years (2000–2006) of basin-wide and zone-wise simulations, (b) an increase of 10% (by 2050) and 20% (by 2075) in SCA will result in a flow rise of ∼11% and ∼20%, respectively, and (c) an increase of 1°C (by 2025), 2°C (by 2050), 3°C (by 2075) and 4°C (by 2100) in mean temperature will result in a flow rise of ∼26%, ∼54%, ∼81% and ∼118%, respectively. This study suggests that SRM equipped with remotely sensed snow cover data is an effective tool to estimate snowmelt runoff in high mountain data-scarce environments. [ABSTRACT FROM AUTHOR]

Projecting future hydrology for the mountainous, highly glaciated upper Indus basin (UIB) is a challenging task because of uncertainties in future climate projections and issues with the coverage and quality of available reference climatic data and hydrological modelling approaches. This study attempts to address these issues by utilizing the semi-distributed hydrological model "Soil and water assessment tool" (SWAT) with new climate datasets and better spatial and altitudinal representation as well as a wider range of future climate forcing models (general circulation model/regional climate model combinations (GCMs_RCMs) from the "Coordinated Regional Climate Downscaling Experiment-South Asia (CORDEX-SA) project to assess different aspects of future hydrology (mean flows, extremes and seasonal changes). Contour maps for the mean annual flow and actual evapotranspiration as a function of the downscaled projected mean annual precipitation and temperatures are produced and can serve as a "hands-on" forecast tool of future hydrology. The overall results of these future SWAT hydrological projections indicate similar trends of changes in magnitudes, seasonal patterns and extremes of the UIB—stream flows for almost all climate scenarios/models/periods—combinations analyzed. In particular, all but one GCM_RCM model—the one predicting a very high future temperature rise—indicated mean annual flow increases throughout the 21st century, wherefore, interestingly, these are stronger for the middle years (2041–2070) than at its end (2071–2100). The seasonal shifts as well as the extremes follow also similar trends for all climate scenario/model/period combinations, e.g., an earlier future arrival (in May–June instead of July–August) of high flows and increased spring and winter flows, with upper flow extremes (peaks) projected to drastically increase by 50 to >100%, and with significantly decreased annual recurrence intervals, i.e., a tremendously increased future flood hazard for the UIB. The future low flows projections also show more extreme values, with lower-than-nowadays-experienced minimal flows occurring more frequently and with much longer annual total duration. [ABSTRACT FROM AUTHOR]

Population growth and population inflow from other regions has caused urbanization which altered land use land cover (LULC) in the lower Himalayan regions of Pakistan. This LULC change increased the land surface temperature (LST) in the region. LULC and LST changes were assessed for the period of 1990–2017 using Landsat data and the support vector machine (SVM) method. A combined cellular automata and artificial neural network (CA-ANN) prediction model was used for simulation of LULC changes for the period of 2032 and 2047 using transition potential matrix obtained from the data years of 2002 and 2017. The accuracy of the CA-ANN model was validated using simulated and classified images of 2017 with correctness value of 70% using validation modules in QGIS. The thermal bands of Landsat images from the years 1990, 2002 and 2017 were used for LST derivation. LST acquired for this period was then modeled for 2032 and 2047 using urban indices (UI) and linear regression analysis. The SVM land cover classification results showed a 5.75% and 4.22% increase in built-up area and bare soil respectively, while vegetation declined by 9.88% during 1990–2017. The results of LST for LULC classes showed that the built-up area had the highest mean LST as compared to other classes. The future projection of LULC and LST showed that the built-up area may increase by 12.48% and 14.65% in 2032 and 2047, respectively, of the total LULC area which was ~11% in 2017. Similarly, the area with temperature above 30 °C could be 44.01% and 58.02% in 2032 and 2047, respectively, of the total study area which was 18.64% in 2017. This study identified major challenges for urban planners to mitigate the urban heat island (UHI) phenomenon. In order to address the UHI in the study area, an urban planner might focus on urban plantation and decentralization of urban areas. [ABSTRACT FROM AUTHOR]

Water shortages in Pakistan are among the most severe in the world, and its water resources are decreasing significantly due to the prevailing hydro-meteorological conditions. We assessed variations in meteorological and hydrological variables using innovative trend analysis (ITA) and traditional trend analysis methods at a practical significance level, which is also of practical interest. We developed threshold levels of hydrological variables and developed a non-parametric climate-sensitivity model of the high-altitude catchment of the western Himalayas. The runoff of Zone I decreased, while the temperature increased and the precipitation increased significantly. In Zone II, the runoff and temperature increased but the precipitation decreased. A two-dimensional visualization of the Pardé coefficient showed extreme drought events, and indicated greater sensitivity of the hydrological regime to temperature than to precipitation. The threshold levels of runoff for Zones I and II were 320 and 363 mm using the Q80 fixed method, while the mean runoff amounts were estimated to be 79.95 and 55.61 mm, respectively. The transient threshold levels varied by month, and the duration of droughts in Zones I and II ranged from 26.39 to 78.98 days. The sensitivity of the hydrological regime was estimated based on a modified climate-elasticity model (εp = 0.11–0.23, εt = −0.04–2.39) for Zones I and II, respectively. These results highlight the sensitivity of the hydrological regime to temperature, which influences the melting process. However, it is important to establish thresholds for hydrological variables and understand the climate sensitivity of the hydrological regime of the entire basin, so that policy makers and water managers can make sustainable water-resource-management decisions for this region. [ABSTRACT FROM AUTHOR]

A study was conducted in Sargodha, Pakistan during the year 2011 to testify irrigation practices as a method for reclaiming salt affected soil. Field experiments were conducted on saline-sodic and uncultivated land divided into 12 field plots. Six irrigation treatments, each replicated on two field plots, were applied to test the responses of soil and wheat crop yield. Six irrigation treatments combined two variables: (i) source of irrigation (canal water, brackish groundwater and mixed in 50:50 proportion) and (ii) irrigation scheduling (fixed-rotation or Traditional Warabandi (TWB) and 75% management-allowed depletion (MAD)). The electrical conductivity (ECe) and sodium adsorption ratio (SAR) of saturated paste extracts of soil were observed at four depth intervals ranging from zero to 90 cm during the four crop growth stages. Only top 15 cm soil layers of field plots could be reclaimed upto the permissible ECe level of < 4 dS/m where canal water was applied for irrigation. In deeper layers (31 to 90cm) the ECe increased from the ambient levels in response to irrigation treatments. The crop yield (wheat grains in kg/ha) was measured from all individual field plots. Canal water application with 75% MAD scheduling proved to be the optimum treatment giving average yield of 1265 kg per hectare while the treatment with groundwater application under TWB showed the lowest average yield (435 kg/ha). [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Malaria is among the most prevalent infectious diseases in the developing countries of world. Estimated number of annual malaria episodes in Pakistan is 1.5 million, but very little is known about medicinal plant species of Pakistan, which have great potential against malarial disease. Present study was aimed to document medicinal plant species used by the local inhabitants of Lesser Himalayas-Pakistan to treat malaria. Materials and methods Data were collected through interviews, questionnaires and contributor observation. A total of 55 informants aged between 25 and 80 years who were familiar with malarial disease participated in the survey. Results A total of 84 plant species belonging to 69 genera and 50 families were recorded to treat malaria. Asteraceae was found as most cited botanical family with (11.9%) representation, followed by Lamiaceae (5.9%), Solanaceae and Verbenaceae (4.7%) and Violaceae (3.5%) respectively. About 60% of the inhabitants prefer herbal treatment by local herbalists or self-treatment with locally available medicinal plant species. Of the plants identified during present investigation against malaria, Azadirachta indica, Swertia chirayita and Swertia ciliata exhibited uppermost frequency of encounter (36.3%) and corresponding PR value 5. About 67.2% of the botanical taxa are reported for the first time in the treatment of malaria. It was observed thatover harvesting is the foremost threat to medicinal plant species of the study area. Conclusion Present survey indicates that traditional knowledge about the use of plant species against various diseases and particularly to treat malaria is in decline. Similarly anthropogenic pressure, over exploitation and grazing of the botanical taxa are the major concerns regarding medicinal plant biodiversity loss. Frequently utilized plant species with significant malarial reduction should be authenticated by in vitro and in vivo standard tests [ABSTRACT FROM AUTHOR]