Climate change and role of anthropogenic impact on the stability of Indus deltaic Eco-region
Journal Title: Journal of Biodiversity and Environmental Sciences (JBES) - Year 2017, Vol 10, Issue 6
Abstract
The Indus River is one of the major river systems of the world and the principal contributor in the creation of the Indus Fan – second largest sediment body in the ocean basins, to talling ~5 x 106 km3. Recent geological and geophysical information obtained from the Pakistan margin suggests that the Indus River and Fan system was initiated shortly after India-Asia collision at ~55 Ma. The Indus River, is currently contributing a fraction of fresh water or sediment in to the Arabian Sea. Consequently, the seawater intrusion has resulted in tidal intrusion in the prime agricultural land in the Indus Deltaic region. Extensive use of fresh water for irrigation in recent years has caused a decline in the down stream discharge of the Indus River. Construction of barrages, dams, and link canals has further reduced the freshwater flow downstream Kotri Barrage from 146 MAF/year to less than 10 MAF/year. In the northeast monsoon period Indus River has practically zero discharge below Kotri Barrage. As a consequence, the river below Kotri shows increased braiding and sand bar development. Sediment passing down the system tends to be deposited in the section south of Kotri, rather than maintaining the growth of the delta. As a result the Indus Delta that used to occupy an area of about 6,180 km2 consisting of creeks, mudflats and mangrove forest is now reduced to 1,192 km2 since the construction of dams and barrages on the Indus River. Pakistan like other parts of the world is also facing a problem associated with sea level rise along with related issues such as coastal erosion and inundation. The analysis of historical tidal data shows that Pakistan coastal sea level has risen in the same way as the global sea level due to global climate change. Besides eustatic sea level rise, the dominance of local factor like subsidence of land may be a catastrophe for low-lying areas. Indus Delta could experience a relative sea level rise of up to 8-10 mm/yr as per the projected rate of global component of sea-level rise of up to 6 mm/yr in the next century. To mitigate the impacts of rising ground water and associated problem of water logging and salinity, a network of drainage canals was constructed down in the Indus Basin to drain saline ground water into the Arabian Sea. The drainage system has been less effective due to low gradient/flat topography and it has in fact resulted in the seawater intrusion into the link canals up to about 80 km upstream.
Authors and Affiliations
Mohsin Muzaffar, Asif Inam, Mahmood Ahmed Hashmi, Khalid Mehmood, Ibrahim Zia, Syed Imran Hasaney
Keywords
Related Articles
- EP ID EP39159
- DOI -
- Views 142
- Downloads 0
Spatial distribution of genus Berberis from Pakistan: A review over three centuries long historical records
For the first time, present study gives a composite outlook of the genus Berberis from Pakistan with spatial distribution along with estimation of total area under occupation. GE Path, Google Earth and ArcGIS have been...
Microhabitats of Pholcid Spiders (Araneae: Pholcidae) in the vicinity of Katibawasan falls, Mambajao, Camiguin, Philippines
The selection of microhabitat by spider communities is influenced by various environmental factors as well as by the plant structure. The study was conducted in the vicinity of Katibawasan falls, Mambajao, Camiguin prov...
Comparative study of biochemical characteristics of halophytes from two different habitats
The worldwide problem of soil salinization may be solved by amelioration of saline soils, or by cultivation and selection of salt resistant plants. That’s why investigation of wild halophytes gains popularity. One of the...
Assessment of Diversity and Distribution of Snails (Mollusca: Gastropoda) in the Agroecosystem of Faisalabad, Pakistan
Gastropods have never been studied in Punjab, Pakistan with reference to its diversity and distribution. Different ecological factors have been studied which affect the distribution of the snail in the agroecosystem of t...
A preliminary checklist of the vascular flora of Kalam valley, Swat, Pakistan
The floristic survey of Kalam valley, Swat was carried out during 2012 to 2014 and a total of 529 species belonging to 312 genera and 85 families were identified. Of them, 14 species of pteridophytes, 11 species of Gymno...