Figure 1.Total area and production of sugarcane in Pakistan (2002–2016).
Source.Pakistan Bureau of Statistics (2016).
Several countries are considered as leading sugarcane producers, including Columbia, where 123.0 tons ha-1 are produced, Australia, Egypt, and the USA produces 99.3, 87.3, and 74.6 tons ha-1 respectively (Devaraja 2008). Pakistan produces around 43 tons ha-1, which is relatively small as compared to the other leading sugarcane producing countries. In Pakistan, sugarcane is produced in the regions of Sindh, Khyber Pakhtunkhwa (KPK), and Punjab, among which Punjab ranks first in sugarcaneproduction (Ur-Rehman, Wassan, and Dost 2012).
Sugarcane is not only a source of income for sugar manufacturers but also for several people in Pakistan who resell sugars and sugar products. Sugarcaneis the source of income for about 64% of the total agricultural output in Sindh(Haq et al. 2013). A total of 91 sugar mills are located in Punjab, 48 in Sindh, and nine in KPK. These sugar mills produce approximately 3.2 million tons of sugar, to meet Pakistan’s demand. There is a significant gapbetween the quantity in whichsugarcaneis produced and the requirement.This gapmay be attributed to bad farming practices, environmental conditions and other conditions that could include the lack of government and other stakeholder facilities (Rana 2018).
Climate change has various causes, but all of them do not impact the production of sugarcane in all regions (Economic Survey of Pakistan 2007). It is true that identification of the primary factors, including climate change, that hinder sugarcane production is necessary. Still, studyingstrategies and measures to address the negative impacts of climate change in Pakistan is far more critical. The main objective of this research is to analyze sugarcane production problems in Sindh, as the sugarcanefarmers face climate change issues and how they can be effectively handled. This study is based on primary data, obtained from the survey, and secondary data that include relevant studies to climate change and sugarcane production. In reality, it is not possible to eliminate the adverse effects of global warming;still, these steps and techniques can be adapted to the unfavorable climate changes impacts on sugarcane production. This study, therefore, examines the particular problems that undermine the capacity of sugarcane production in the Sindh province of Pakistan.
Literature review
Approximately 70% of the Pakistani population is linked directly and indirectly to agriculture.Businesses produce raw materials and fertilizers for farmers; some companies use agricultural products; and farmers earn their sustenance (Rana 2018).
The temperature effects on the rate and efficiency of photosynthesis are directly linked to the growth of crops. Studying air temperatures between 34 and 5 °C, Waldron, Glasziou, and Bull (1967) observed a linear decrease in the efficiency of photosynthesis. Sugarcane needs optimal temperature,otherwise the yield is reduced. Extreme temperatures cause a severe reduction in the yield of sugarcane due to its physiology, biochemistry, and quality, which lead to poor agricultural products. During planting, low or high temperature influences germination, cultivation, and the viability of early growing crops such as sugarcane which are dependent on the temperature. Several experimentshave been carried out to boost the quality of sugarcane at high and low temperatures.Stender (1924) showed a close relationship between the stalk’s length and diameter and air temperature, with a drop of one-third in the growth rate in the winter against that observed in summer. The reduction in stalk growth rate, either in length or diameter, is followed by an increase in the rate of sucrose accumulation. The physiological ripening process of sugarcaneis dependent on the seasonal reduction in air temperature, which slows growth rates(Alexander, 1973; Mamet & Galwey, 1999). However, this decline in the levels of growth does not affect the photosynthetic process significantly. This can make it possible to prevent further photosynthesis. Cardozo (2012) noted an inversely proportional relationship between air temperature and sugarcane ripening, with higher correlation coefficients found when the air temperature was measured 120–150 days before sampling, which is in accordance withthe findings of Clement (1962).
Glasziou et al. (1965) found that when the air temperature reduced over a long period, high sugar content was achieved. According to them when the air temperature is constant or when minor normal temperature fluctuations occur, sugar concentration does not reach 12% of the fresh weight. However, when the average air temperature decreases over a long period, that is, three to six months, the concentration of sugar exceeded 17% of the fresh weight. There is no consistency among researchers about the thermal parameters for sugarcane, which are primarily related to the base temperatures, as various baseline temperature values are proposed which may differ depending on the location, cultivars, and phenological process (Scarpari andBeauclair 2004).
Barnes (1964) considered the basic shooting temperature to be 12 °C, while Inman-Bamber (1994) found a base temperature of 16 °C for tillering.Bacchi and Souza (1977) reported values between 18 and 19 °C for the internode elongation period. The earliest cultivars (SP91-1049 and SP86-155) were higher in ripening of sugarcane, varying between 20 and 21 °C, whilethose in the middle (RB867515) werelower ripening cultivars (SP 83-2847), between 18 and 19 °C, as examined by Cardozo (2012),who found discrepancies in the base temperature. According to Cardozo (2012), the higher the base temperature, the smaller the rate of growth under low air temperature, explaining the precocity of specific crops in comparison to others. Late cultivars are less sensitive to low air temperature than the early ones; they continue their growth for longer periods, thus delaying their ripening.
Various reforms to boost agricultural markets in the undeveloped countries have been addressed in previous studies but the environmental aspect of these reforms has been skipped. Improvements need to be made with concerted steps to tackle the detrimental side of climate change as the implications of climate change cannot be avoided. A study related to sugarcane production was conducted in 2003.The results suggested that sugarcane should be used as a substitute for sweeteners instead of exporting it as a raw material. The study was carried out using Policy Analysis Matrix (PAM), Domestic Resource Costs (DRC), and social benefits and cost (SBC) analysis, which supported sugarcane’s competitiveness in Pakistan (Khan, Farooq, and Saddozai 2006).
Tayyab et al. (2018) examined some of the bacterial diseases that occurred in crops because of climate change. Their study confirms the need of high quality fertilizers to deal with bacterial attacks on sugarcane. The occurrence of diseases is partly due to the climate change in Pakistan.
While several reasons have been identified for the poor production of sugarcane in Pakistan, environmental factors have been ignored. The survey introspected several of the reasons,for instance, high cost of land, unskilled labor, and lack of extension services, adequate training for farmers, and access to financial facilities in rural areasapart from prevalence of conventionaltechniques and methods as well as little information regarding marketing. Despite the existence of several policies and programs of the Government of Pakistan for farmers,a focus on environmental factors is lacking, whereas this cannot be managed instantly as it requires time and effort.(Bhutta, Ilyas, and Usman, 2019). In Pakistan, the potential for producing sugarcane on a large scale is very high, but due to several reasons and factors, actual production is below average.
Sugarcane goes through two critical phases, growing phase and ripening phase. In the first phase, bright sun with high humidity as well as an optimum level of rainfall are required, while during the ripening phase, dry weather with less precipitation is needed; otherwise, the yield will be damaged (Girei and Giroh 2012).Also, saline soil is not suitable for sugarcane production (Husain and Khattak 2011). The pH level in water as well as high nutrients in the soil play a significant role in sugarcane growth and pH up to 8.5is tolerable (Sharif et al. 2014). Heat wave has increased in Pakistan due to high emission of CO2 and this has impacted the working conditions for sugarcane laborers,as sugarcane grows in bright sunlight with high radiations. High intense heat also contributes to rapid evaporationof water from the soil and plants which creates demand for more water for the production of sugarcane. Drought is also the major factor that affects crops,especially sugarcane yields,as tube wellsare not able to provide the required water and farmers depend on rainfall and canal water(Aslam 2016; Qureshi 2011). Because of the adverse effects of climate change, farmers need pesticides to counterclimate-related diseases. These pesticides are, on the other hand, sold at higher prices, (Bhutta, Ilyas, and Usman, 2019).
Many countries, including Pakistan, have been affected by the climate change. The causes of the intensified heat waves and climate changes worldwide are established, but to a certain degree, they are uncontrollable. In reality, CO2increase can be regulated or decreased but cannot be entirely prevented (Qureshi et al. 2008). Climate change has many negative consequences in Pakistan that haveaffected almost every region and areas like forests, biodiversity, people and food production (Qureshi et al. 2010; Ur-Rehmanet al., 2012).
Several studies have been carried out on sugarcane production. Still, none of them addresses abiotic stress management practices (climate changes) to increase the production rates. According to Khan, Farooq, and Saddozai (2006), sugarcane has to be produced and consumed in Pakistan instead of being exported. Their study was based on an analysis of social benefits and resource costs. While Farid(2012) conducted a research in KPK, which show that the projects of farms are economically profitable and must be encouraged in Pakistan. This research was focused on a model of cost–benefit analysis, based on the data from surveys and did not cover the environmental factors.
A significant experiment was carried out by Khan, Khan, and Khan, (2012) to evaluate the cost–benefit analysis of sugarcane production. On the other hand,Husain and Khattak (2011) conducted a research to examine the relationship between sugarcane production and the various factors that included resources, labor, and marketing but ignored the environmental factors. Also, no study has been undertaken in which sugarcane growers’ views and suggestions to reduce the ill effects of climate change were discussed. Based on the experimental design, in which secondary data was collected, Sharif et al. (2014) observed that white sugar is consumed more and should be produced moreto achieve more profit. This study does not answer what strategies and measures should be taken by sugarcane producers to deal with climate change. Indeed, suggestions and opinions of sugarcane growers of the Sindh region in Pakistan are worthy in dealing with climate change effects as they experience the impact of climate change directly. Pakistani government officials have reported that sugarcane production will decline in Sindh by the end of 2019. There is a higher volume of taxes and duties, but there is no strong evidence of environmental resistance (Sugarcane, 2018; Land Degradation in Sindh, 2002). In Pakistan 83% of the total sugarcane farmers are landowners but are not yet able to grow sugarcane in large, due to environmental factors(Cheema et al., 2019).
Many researchers have considered different factors responsible for carbon emissions. In these research studies, several factors of climate change that affects the agricultural sectorhave been investigated. Still, no specific research has been done on the specific issues of climate change in Sindh. These factors are major obstacles in achieving a high sugarcane growth, even when farmers use sophisticated modern technologies and are willing to invest in terms of time and money. Khan et al.(2012) assessed the relation between the production of sugarcane and different factors including capital,labor, and marketing, but their study did not cover environmental factors. So far, these studies have not considered what policies and steps should be made to cope with climate change factors. In reality, sugarcane growers from the region of Sindh in Pakistan have suggestions and views worth considering when dealing with the impact of climate change. In view of the above discussion, the main objective of this study are: