Despite these gains, expanding rice production comes with sustainability challenges due to its high environmental impact, particularly in terms of carbon emissions and water usage. The traditional practice of continuously flooding rice paddies creates low-oxygen environment in soil, leading to substantial methane emissions—a potent GHG that accelerates climate change. This irrigation method also results in high evaporative water losses, making rice cultivation the largest consumer of freshwater in Pakistan.
Rice is the largest consumer of irrigation water used in the country, while contributing only 1% to its GDP. Although recent reforms in Punjab shifted water pricing mechanisms to crop-specific rates from a flat rate per acre to promote crop diversification, the changes were ineffective. Low water prices failed to incentivize the adoption of water-saving technologies. Small landholdings without on-farm water storage systems further undermine efforts to improve water use efficiency, as farmers cannot store excess water for future use.
In Punjab, the leading rice growing province, more than 50% of irrigation water is sourced from groundwater, threatening a decline in groundwater levels in areas served by several canals. In addition, the government’s subsidies for solar-powered tube wells in Punjab—introduced without sufficient consideration of groundwater sustainability, could exacerbate the problem because the high price of electricity and fuel incentivizes judicious use of groundwater.
Meanwhile, Sindh—the second largest rice-producing province—faces a different challenge. While groundwater in most of Sindh is not suitable for irrigation, competition for water among various sectors has led to a continuous reduction in water availability for rice farming.
With increasing focus on sustainability, agricultural industries are expected to demonstrate their environmental credentials, particularly in markets such as Europe that import rice from Pakistan. The prospect of future carbon tax implications further incentivizes the production of low-carbon rice.
However, the lack of actual quantification and national capability in quantifying GHG emissions from rice fields mean that claims about the carbon footprint of rice and its mitigation potential are anecdotal, with limited credibility and authentication.
Additionally, the large variability across country’s rice ecosystems results to significant uncertainties in estimating emissions from rice production using the current standards of the national GHG inventory.
To track the country’s progress and ensure transparency, it is crucial to establish a scientific national GHG inventory. This would enable Pakistan to meet its national targets while providing a transparent framework for the agricultural sector and other industries.
