Spatio-temporal patterns of land cover changes under variable hydrological conditions in the Indus Delta
Muhammad Zia-ur-Rahman*
Kashif Majeed Salik **
Urooj Saeed and Naeem Shehzad***
Waheed-ul-Zafar Zahdi****
The Indus Delta is considered one of the world’s most threatened large deltas due to climate change induced threats to the existence of Hindukush-Karakorum-Himalaya (HKH) glaciers feeding River Indus and increasing upstream freshwater diversions to a vast irrigation network. This study aims to assess changes in land cover including the all-important mangrove forests of Keti Bunder (Sindh, Pakistan) in response to changes in the local hydrological conditions (e.g. wet, dry, river flooding) by comparing land cover status for various hydrologically significant years from 1987-2011. The land cover mapping performed in this study employs a recently introduced Object Based Image Analysis (OBIA) technique. Land cover comparisons were presented in three settings i.e. wet regime vs. start of a dry regime; start of drought regime vs. end of drought regime; and before river flooding vs. after river flooding.

Results of this comparative analysis show that there is a strong linkage between freshwater regime and land cover/use in the study area as the areal coverage of different important land cover classes including mangrove forests and agricultural land fluctuates in-phase with fluctuations in freshwater supply. Thus, projected changes in freshwater flows of the Indus basin under climate change, is going to be a major challenge for survival of the deltaic communities and low riparian ecosystems.
* Muhammad Zia-ur-Rahman Hashmi works with the Global Change Impact Studies Centre (GCISC), Water resources and Glaciology section, National Centre of Physics Complex, Quaid-i-Azam University Campus, Islamabad, Pakistan.
** Mr. Kashif Majeed Salik is Research Associate at Sustainable Development Policy Institute, Islamabad.
***  Ms Urooj Saeed and Mr. Naeem Shehzad work with the World Wide Fund for Nature (WWF), Islamabad, Pakistan.
**** Mr. Waheed-ul-Zafar Zahdi works with the Sustainable Development Policy Institute (SDPI), Islamabad, Pakistan.