Climate change is impacting agricultural production in Pakistan, threatening the country’s development given its high economic dependence on this sector.
Specifically, changes in rainfall and temperatures combined with rising instances of flooding are reducing crop yields and reducing the number of goods going to market.
Traditional farmers are particularly vulnerable to the impacts of climate change due to growing uncertainties on the best times for planting and harvesting, suitable methods of irrigation and fertilization, and the long-term impacts of using agrochemicals.
In this context, the development and widespread adoption of climate-smart interventions can assist in counteracting the numerous risks involved and help promote food security.
Punjab province, Pakistan’s major crop-producing area, has a large network of canals that distribute water to much of its 12.6 million acres of cultivated lands.
Wheat, rice, maize, cotton, and sugarcane yields contribute to 21.7 percent of Pakistan’s total income, and the province has seen an exponential rise in the cultivation of such crops since the 1960s.
However, these crops are dwindling at a time when population and agricultural demand are on a steady increase, threatening both the food and economic security of the province and Pakistan as a whole.
There is an urgent need to evaluate climate change impacts and develop effective smart interventions for small-holder farms in Punjab.
One such intervention is crop modeling, which is becoming a useful tool for understanding the projected impacts of climate change on the agriculture sector. These modeling studies can also assist policymakers with their decision-making process.
The link between rising temperatures and rainfall and reduced agricultural output
Punjab is getting warmer, and warmer climates restrict the type of crops that an area can produce.
The annual temperature will likely increase by about 3.3°C by the 2050s, while climate models predict that southern and central Punjab (3.6°C) is getting hotter than northern Punjab (2.8°C).
Using a Decision Support System for Agro-technology Transfer (DSSAT) and Agricultural Production Systems sIMulator (APSIM), it is estimated that southern Punjab will lose up to 47 percent of its cotton yields due to temperature and precipitation changes.
This translates into a monumental loss for cotton farmers and will push up the number of farmers living in poverty in the area (i.e., on or under US$1.25 per day) from 1.2 percent to 17 percent by the 2050s.
Furthermore, any increase over 40°C will decimate cotton crops as it will cause shedding of bolls and damage the quality of fibers.
In central Punjab, rising temperatures will reduce the maize yield by 29 percent by the 2050s as optimal growing seasons are shortened and grain development is restricted.
Rice yields in northern Punjab will decrease by 17 percent as high temperatures reduce grain sizes and weight, ultimately leading to significant crop losses for an estimated 83 percent of small-holders and an increase in the poverty rate from 5 to 6 percent in this area.
Apart from local warming, an increase in rainfall variability, shifts in the seasonal distribution of rainfall, and a growing frequency of extreme events can drown or dry-out crops.
Projected changes in rainfall for the mid-century are uncertain, with some models indicating wetter or stable conditions, while others indicate possible decreases of up to 52 percent in rainfall during the cotton-growing season and up to 42 percent during the wheat-growing season in southern Punjab.
In central Punjab, annual precipitation could decrease by 73 millimeters by the mid-century, and the rainfall projections in northern Punjab showed an increase (about 25 percent) in summer rainfall and a decrease (12 percent) in winter rainfall by the mid-century.
Indeed, warm days and warm spells have become more frequent, maximum and minimum temperatures have increased, and rainfall patterns are becoming ever more uncertain.
These climate change impacts will continue to impact agricultural productivity without sufficient use and adoption of climate-smart interventions like crop models.
Development of climate-smart interventions
Smart management practices for today’s farms should be able to reduce the negative impacts of climate change, improve yields in current conditions, and reduce future vulnerabilities.
In southern Punjab, better methods of fertilizer application, increases in sowing density and early sowing dates, as well as the cultivation of heat and drought-tolerant plant varieties will support climate-resilient wheat production.
For cotton, the balanced application of fertilizers (nitrogen, phosphorus and potassium), widening row spacing to 15 percent more than is recommended, cultivating resilient varieties, and providing cash subsidies to small-holder farmers during cultivation periods would have positive impacts on farm returns and per capita income.
If applied correctly, such interventions could increase wheat production by 21 percent and cotton yield by 33 percent.
In central Punjab, the application of nitrogenous fertilizer with irrigation water (known as fertigation), sowing 15 days early, increasing nitrogen fertilizer and plant populations by 10 percent each, and developing heat-tolerant cultivars are all supporting maize and pearl millet (Ahmad et al, 2019, 2020).
The practicality of these interventions in the field in central Punjab was assured with the help of farmers and field researchers, resulting in an increase in maize yield by 21 percent and pearl millet yield by 15 percent.
For northern Punjab, sowing of high yielding varieties, increased plant populations by up to 30 percent for wheat and up to 15 percent for rice, shifting sowing dates earlier by about 15 days for wheat and 5 days for rice, increasing fertilizer up to 25 percent for wheat and 15 percent for rice are also practical responses to climate change.
It is anticipated that farmers adopting these interventions would be able to reduce poverty in the area by about 13 percent by the 2050s.
Therefore, it is suggested that the extension agent in Punjab should communicate/demonstrate these adaptation strategies to farmers.
It is concluded that the average annual temperature in Punjab is expected to rise by 2-3°C, which would reduce the crops yield by 13 to 50 percent in 2050s.
Climate-smart interventions such as the development of heat/drought-resistant cultivars, an adjustment in row spacing, alternate natural fertilizers, earlier planting dates, and increased plant populations, would increase the yield of crops from 15-21 percent in various crops.
To implement climate-smart interventions correctly, coordination and cooperation is required between local farmers and local decision-makers.
On the policy aspect, soil and water conservation practices, construction of water storage, and efficient irrigation systems should be ensured, while institutional measures that anticipate changing climate conditions like agricultural insurance and farm mechanization (mechanical harvester/picker for cotton) should be provided to the farmers.
This would have a positive impact on agricultural production and ensure food security despite the changing climate.
The writer is Resilient Agriculture Specialist, ADPC, and can be reached at:
ishfaq.ahmad@adpc.net