Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya (HKH) region. The ...existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation (RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., <5 t/(ha·yr), 15.8% area low risk, i.e., 5–25 t/(ha·yr) and 7.5% area moderate risk, i.e., 25–50 t/(ha·yr) in the region. The risk was high, i.e., 50–100 t/(ha·yr) and very high, i.e., >100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic development in the region in future.
Climate change is posing high risk for glacial resources of the Indus basin on which hundreds of millions of people depend for their sustenance in the downstream. In the present study, impact of ...climate change was investigated on the multi-water resource regimes of Upper Indus Basin and lower Indus plain of Pakistan adopting integrated statistical and hydrological modeling approach. The findings of the study revealed higher rate of temperature rise in the Upper Indus Basin (UIB) than in the lower Indus plain. An inverse relationship was observed between glacier area and mean temperature as well as rainfall (significant at
p
< 0.05) averaged over 10 sub-basins of the UIB. In contrast, lake area exhibited a positive correlation with both temperature and rainfall parameters. Similarly, river discharges of the sub-basins exhibited a fair positive correlation with mean temperature and rainfall. The groundwater regime in the Indus plain appears to respond indirectly to changes in climate, i.e., via variations in surface recharge and discharge conditions. However, such interactions between various parameters and their role in regional hydrology need a thorough investigation in context of projected changes in climate in this region.
There are serious concerns of rise in temperatures over snowy and glacierized Himalayan region that may eventually affect future river flows of Indus river system. It is therefore necessary to ...predict snow and glacier melt runoff to manage future water resource of Upper Indus Basin (UIB). The snowmelt runoff model (SRM) coupled with MODIS remote sensing data was employed in this study to predict daily discharges of Gilgit River in the Karakoram Range. The SRM was calibrated successfully and then simulation was made over four years i.e. 2007, 2008, 2009 and 2010 achieving coefficient of model efficiency of 0.96, 0.86, 0.9 and 0.94 respectively. The scenarios of precipitation and mean temperature developed from regional climate model PRECIS were used in SRM model to predict future flows of Gilgit River. The increase of 3 _C in mean annual temperature by the end of 21th century may result in increase of 35e40% in Gilgit River flows. The expected increase in the surface runoff from the snow and glacier melt demands better water conservation and management for irrigation and hydel-power generation in the Indus basin in future.
Rapid deglaciation in form of lowering of glacial surface under growing warm temperatures form a major cause of disruption in meltwater flows to cryosphere-fed irrigation network which usually ...affects the agriculture productivity and livelihoods in the Upper Indus Basin (UIB). In such hotspots of cryosphere change and other vulnerable areas, solar powered irrigation system (SPIS) can be adopted as a nature-based solution to uplift water from the nearby glacio-fluvial streams for irrigation and domestic use. In the present study, solar energy harnessing potential was investigated in the UIB region of Pakistan based on climate and topographic suitability to adopt solar powered irrigation system (SPIS) in the region. Overall mean temperature and elevation were found suitable for harnessing solar energy in major parts of the Hindu Kush-Karakoram-Himalaya (HKH) ranges of the UIB. The slope index indicated high suitability for harnessing solar energy in about 92.5% area, while aspect exhibited high suitability in about 13.3% area and medium in 25.3% area of the HKH region. The slope-aspect (SLA) suitability was found good in about 13.5% area of the Hindu Kush, 12% of the Karakoram and 10.9% area of the Himalaya range, whereas it was observed medium in about 26.7% area of the Hindu Kush, 21.8% of the Karakoram and 22.2% area of the Himalaya range. Overall the SLA suitability was found good in about 12.1% area and medium in about 23.5% area of the three HKH ranges. However, maximum benefits of the SPIS approach can be acquired through linking it with integrated water resource management approach for sustainable agricultural water management in the region.
The retreating behavior of glaciers observed in most of the Hindu Kush–Karakoram–Himalaya (HKH) region has given rise to the formation and expansion of numerous glacial lakes in the region. The lakes ...expansion under changing climate usually poses high risk of glacial lake outburst flood (GLOF) hazard for the downstream communities. In the present study, the risk of glacial lake outburst flood was investigated in the HKH region of Pakistan using LANDSAT-8 OLI (Operational Land Imager) image data of 2013 period coupled with ground information. The results of present study revealed 3044 lakes (surface area about 134.8 km
2
) in the three HKH ranges, maximum in the Karakoram (1325) and minimum in the Hindu Kush range (722) during 2013. The lakes exhibited an overall increase of about 26% in number and 7% in area in the region during 2001–2013 period. The increase in lake number was 91% within 2500–3500 m, 20% within 3500–4500 m and 31% within 4500–5500 m elevation range. Among total identified lakes during 2013, 36 were characterized as potentially dangerous glacial lakes (PDGLs) that can pose GLOF hazard in the HKH region. A regular monitoring of cryosphere changes and critical glacial lakes is essential to develop sustainable risk management strategies for this region in future.
Snow and glacier melt runoff supporting agriculture and livelihoods of large number of communities is becoming highly vulnerable to recent changes in climate and cryosphere in the Himalayan region. ...In the present study, potential for expanding base of glacier-fed irrigation system was assessed through adopting water availability and topographic suitability indexing approach in the Astore basin, of Pakistan. Availability of glacier-melt water was found 2.0 L/sec/hectare (lps/ha) over high topographic suitability area (0–15° slope < 3500 m), 0.8 lps/ha over combined high and medium suitability area (0–30° slope < 3500 m), and 0.9 lps/ha over net culturable land in the basin. These estimates point toward adequate meltwater availability for establishing kuhl system over high and medium topographic suitability areas in the basin. The scenarios of 20%, 40%, and 60% reduction in glaciated area indicated adequate meltwater runoff for crop farming over high topographic suitability, while the water availability was observed low over medium suitability and net culturable areas. A long-term research on changing climate and cryosphere would be important to understand the hydroglacial dynamics and implications for water resource management in this region in future.
A three-dimensional groundwater flow model was developed using Visual MODFLOW to characterize the groundwater regime and simulate groundwater flow behavior in Multan District of Pakistan from 1962 to ...2015. The multi-layered model was calibrated in which arsenic concentration was used as a point source for solute transport modeling in the flow domain. The model calibration indicated a close agreement between the simulated and observed head values achieving residual mean value of 0.1 m and a correlation coefficient (
R
) value of 0.9 during the steady-state condition. The study revealed a gradual rise in groundwater levels from 1972, i.e., at a rate of about 0.08 m/year followed by a gradual decline after 1990 at a rate of about 0.39 m/year likely due to overexploitation of groundwater. The other reasons of depletion of the aquifer may include lesser natural recharge due to reduction in canal command area and increasing water demand and pumpage due to growing urban/rural development. The findings of contaminant transport modeling depicted flow path representation of arsenic movement mostly towards the rivers in the model domain. Overexploitation of groundwater needs to be controlled for effective development of groundwater resource, and proper purifying/filtering techniques have to be adopted to ensure safe groundwater use in the area.
Cryosphere-fed kuhl irrigation system forms a major lifeline for agriculture and livelihood development in the Himalayan region. The system is highly vulnerable to climate change impacts like glacier ...retreat, glacial lake outburst floods, snow avalanches and landslides especially in the upper Indus Basin (UIB). It is necessary to conduct reassessment of climate change impacts and find coping strategies for sustainable agriculture development in this mountainous region. In the present study, risks of glacier depletion , lakes outburst flood, snow avalanche and landslide hazards impacting cryosphere-fed kuhl irrigation system in 10 river basins of the UIB of Pakistan were analyzed using multi-hazard indexing approach. High risk of glacier depletion was observed in the Astore and Swat river basins likely because of the combined effect of reduced snow precipitation and rising warm temperatures in these basins. The risk of expansion in aggregate lake area was high in the Indus sub-basin, moderate in the five basins (i.e., Hunza, Shigar, Shyok, Shingo and Astore), while it was low in the four basins (i.e., Swat, Chitral, Gilgit and Jhelum). More than 2% areas of Hunza and Shigar basins in the Karakoram range exhibited high risk of snow avalanche and landslide (SAL) hazard, while moderate SAL hazard was found in >40% areas of Chitral, Gilgit, Hunza and Shigar river basins. An effective early warning mechanism and provision of adequate resources for preparedness are essential to cope with negative impacts of climate change on irrigated agriculture in this region in future.
Climate change is expected to have a significant impact on the Himalayan region, which may ultimately affect the water security and agriculture productivity in the region. Investigations of ...hydrologic regimes and their linkage to climatic trends are therefore gaining importance to reduce vulnerability of growing implications in the region. In the present study, the eWater source software implementation of GR4JSG snow melt model was used for snow melt runoff modeling of the Astore river basin, western Himalayas. The model calibration and validation indicated a close agreement between the simulated and observed discharge data. The scenario of 0.9 °C increase in temperature indicated 33% rise in the river discharge, while an increase of 10% in precipitation may exaggerate the river flows by 15%. The scenario of 100% increase in glaciated area showed 41% increase in the Astore river discharge. On the other hand, reduction of 50% glacier cover may result in 34% decline in the river discharge, while 0% glacier coverage may reduce the river discharges by 49% from that of the base year 2014. It is essential to develop a long-term water resource monitoring process and adapt water management systems taking into account the socio-economic and ecological complexities of the region.
Glacial lake outburst floods (GLOFs) have been intensely
investigated in High Mountain Asia (HMA) in recent years and are the most
well-known hazard associated with the cryosphere. As glaciers recede ...and
surrounding slopes become increasingly unstable, such events are expected to
increase, although current evidence for an increase in events is ambiguous.
Many studies have investigated individual events, and while several regional
inventories exist, they either do not cover all types of GLOF or are
geographically constrained. Further, downstream impacts are rarely
discussed. Previous inventories have relied on academic sources and have not
been combined with existing inventories of glaciers and lakes. In this
study, we present the first comprehensive inventory of GLOFs in HMA,
including details on the time of their occurrence, processes of lake
formation and drainage involved, and downstream impacts. We document
697 individual GLOFs that occurred between 1833 and 2022. Of these, 23 %
were recurring events from just three ephemeral ice-dammed lakes. In
combination, the documented events resulted in 6906 fatalities of which 906
can be attributed to 24 individual GLOF events, which is 3 times higher
than a previous assessment for the region. The integration of previous
inventories of glaciers and lakes within this database will inform future
assessments of potential drivers of GLOFs, allowing more robust projections
to be developed. The database and future, updated versions are traceable and
version-controlled and can be directly incorporated into further analysis.
The database is available at https://doi.org/10.5281/zenodo.7271187 (Steiner and Shrestha, 2023), while
the code including a development version is available on GitHub.
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