Impacts of climate change on crop production in Pakistan, future challenges and mitigation strategies

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CLIMATE change is a rising issue of agriculture that has a direct impact on crops productivity. Since 4.5 billion years of earths formation, its climate has been constantly changing, but these changes mostly occur on two scales i.e. astronomical and geological, and are too slow to observe on a human scale. Climate change is associated directly or indirectly to human activities that alter the global atmospheric composition, which in addition to natural climate variability observed over comparable time periods. Pakistan is ranked 28th amongst severely affected countries from climate change. Pakistan is an agriculture based country, almost 47% of Pakistans population is earning livelihood through agriculture sector, and contribution of this sector in Gross Domestic Product (GDP) of country is believed to be 24%. In 1980-81, agriculture sector was contributing 31% in the countrys GDP whereas in 2012-2013, it has mowed down to 21.4% (Economic survey of Pakistan, 2013). Climate change is alarming to crop productivity in regions that are already food insecure. Climate change and crop production are interrelated. It is necessary for a country to make its agriculture sector well organized to foster food security, quality of life, and to support rapid economic growth.


Two crop seasons prevail in Pakistan that is Rabi and Kharif. Rabi crops are normally grown from November to April and Kharif crops from May to October. The performance of these seasons depends upon climatic variation during the whole year. Wheat, Maize, and rice contribute to 80% of the global cereal production. Crop productivity is affected by climate variables like temperature, rain that is in two ways direct and indirect impact. Direct impact includes plants evapotranspiration rate, soil moisture, plant intake status and plant yield affect its respiration and photosynthesis processes, indirect impact includes plants pest and disease influx processes which are triggered by increased humidity and temperature in atmosphere. Intense temperature results in increased evapotranspiration rate that ultimately leads to high irrigation water demand. Temperature has raised about 1 ̊C during last century due to deforestation and fossil fuel burning causing enormous negative effects on crop productivity as well as on environment.


Due to climate change, growing season length of wheat will be reduced that have negative effect on yield. The increase in air temperature shortens winter season and the productivity of some Rabi crops will be greatly affected. It is estimated that there would be 1.2-2.8 ̊C rise maximum while 1.0-2.2 ̊C rise in minimum temperature during early and mid century in rice-wheat cropping system in Punjab. The productivity of these crops is seriously affected. It is likely that there would be increase in growing degree days up to 8% and 15% in 2020 and 2050 with rainfall decrease by 6% and net irrigation water requirements could increase by 29%.


There is an increasing trend of maximum temperature (heat) from 2010 to 2014, and afterwards minimum temperature (cold) increases which shows the dynamics of minimum and maximum temperature during five years.


In climate alteration, flooding is distinguished symptom that eventually schedules a meeting with disaster and poverty. Recurring floods have been responsible for dribbling trend in Pakistans economy since last few decades. Pakistan had confronted two successive floods during 2010 and 2014, which lead to malnutrition, hunger, dismissing several families, and encouraged poverty. Disaster during 2010 encompasses crop losses like cotton, sugarcane, rice, pulses, wheat, livestock loss and it also knocked the GDP to 3%. In 2008-2009 there were desiccative conditions, as rainfall was less than optimum level, whereas from 2010- 2014, rain fall occurred more than optimum level that prove to be a reason for flood meandering in various parts of Punjab.


In Pakistan, the GDP is lowered due to persistence drought because of poor performance and management of agriculture sector. Countrys economy is badly affected due to continuous drought spell particularly in Sindh and Balochistan. In these areas, drought has reduced the river flow thus resulting in drying up of irrigation canals, leading to severe scarcity of agricultural water. Seasonal monsoon of March is disturbed by climate that inflicts serious challenges to sustainable crop production. In 2009, International Food Policy Research (IFPR) reported that South Asia would be severely impacted by climate change. It will approximately lose 50% of its wheat productivity by 2050. At large, agriculture on Indus valley is in danger that is directly and indirectly impacting on agriculture that could cause hefty loss. Under the climate change scenario, producing high delta water consuming crop like sugarcane may perhaps no longer practicable. The price of sugar is doubled than the past, creating social disorder and political embarrassment.


Climate change exposes to risk of glacial retreats, temperature increase, sea level rise, more frequent floods and droughts. The land of Pakistan is mostly arid and semi arid, expected changes in temperature and rainfall patterns in the future could halt its food security and the welfare of millions of its people. There is less availability of water with the increased requirement of irrigation water due to higher evapotranspiration rate at higher temperature. After a heavy rainfall and flood, there is abundance of insects, pests, and pathogens in warmer and more humid environment.


There is need to take immediate adaptation measures aimed at its agriculture sector, that will help to stable its agriculture growth rate at around 5% above the population growth rate of 2.4%. Implementing industrial polices and national energy polices which would contribute climate mitigation by avoiding Green House Gases (GHG) emission. To overcome the effect of climate changes taking measures such as developing new and innovative farm production practices, improve productivity, and production measurement, changing in cropping pattern like sugar beet instead of sugarcane. Through the progress in genetic researches, short duration varieties have been established for wheat and other Rabi crops and heat and moisture stress resistance varieties for wheat, maize, rice, cotton and sugarcane. Adjusting cropping pattern with water availability i.e. more share of cropped area under oil seed crop. New crop varieties should be introduced thus encouraging and adopting high irrigation efficiency systems and techniques. Flood irrigation should be avoided and modern resourceful irrigation methods should be adopted such as use of drip, sprinkler, and trickle irrigation system in order to overcome the water shortage, protect the fertile soil reducing seepage from the canal and distribution networks. By adopting these measures, we certainly can reduce the adverse effects of climate change on crop yield, ensuring food security, thus reducing poverty level in Pakistan. We have to cope with climate change scenario at regional, national, and global level through establishing comparative advantage in agriculture and agro-based industries. It is significant to raise public awareness about climate change issues. We have to analyze and evaluate the impact of climate change on socio-economic development of Pakistan.


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Published in: Volume 06 Issue 13

Short Link: http://www.technologytimes.pk/?p=13002