Climate change has emerged as a global concern in the past 20 years. One particular worry is the potential disastrous consequence for agriculture and food security in many parts of the world, especially in developing countries. Crop production is extremely vulnerable to climate change and it has been predicted that climate change will impact negatively on agricultural yield in the 21st century through higher temperatures, more variable rainfall and extreme climate events such as floods, cyclones, droughts and rising sea levels (Reza, 2019). The United Nations Framework Convention on Climate Change also identifies the danger to food production as a major concern.
In Bangladesh, People directly or indirectly depend on agriculture. Coastal areas constitute about 2.5 million hectares, which cover about 25% of the total crop land of the country. Of this, nearly 0.84 million hectares are affected by varying intensities of salinity, resulting in very poor land utilization (Reza, 2019). In the Southern Khulna region (Paikgacha) 5.18 mm/year sea level rises has been recorded which may go up to 85 cm by 2050.
Geographic Feature of the Study Area
Paikgachha is located between 22°28' and 22°43' north latitudes and between 89°14' and 89°28' east longitudes (Fig 1). The upazila is bounded on the north by Tala upazila of Satkhira district and Dumuria upazila of Khulna, east by Shibsa river, Batiaghata and Dacope upazilas, south by Koyra upazila and west by Tala and Assasuni upazilas of Satkhira district. The upazila occupies an area of 411.19 sq. km.
Fig 1: Map of Paikgacha Upazila, Khulna, Bangladesh
Climate, Agriculture and Cropping Pattern
Only 36% people involve in agriculture in Paikgacha upazila. People are not interested to involve in agriculture because of low production rate. Crop production rate is low in this area due to excessive soil salinity. At present total cultivable land in this area are 24,918 ha. In Paikgacha, there one crop land (12,000 ha), two crop land (5,368 ha) and three crop land (7,550 ha). In this area, the classifications of land are: high land 2,850 ha, medium land 5,350 ha and medium low land 17,093 ha. Paddy (Amon, aus, boro), jute, wheat are the main crops in the study area. Water melon is also grown well in this area. The study area’s climate is tropical in nature dominated by the south-west monsoon of the Indian Ocean. There are three distinct season warm (March to May), monsoon (June to October) and cool season (Nov. to Feb). In on average 70% to 80% of the annual rainfall occurs during the monsoon period. The cool season is generally pleasant and comfortable. Rainfall in this season is frequent. There are two major cropping season found in the Ganges belt area Rabi and Kharif season. Temperature and rainfall is important for these two seasons, as plants in the field are growing depending on rainfall pattern and temperature changes.
Methodology and Results
Primary data were collected by direct interviews. The study conducted with a semi-structured qualitative questionnaire to allow for in-depth discussion with local people in the Paikgacha upazila. Secondary data used in this research were collected from the Department of Agricultural Extension, Paikgacha,; Upazila Statistics Office, Paikgacha, Khulna; Soil Resource Development Institute (SRDI), Khulna; Bangladesh Metrological Department (BMD), Dhaka.
Monthly Income of the Respondents
On the basis of monthly income, the respondents are classified into four categories. The categories are 5000-10000, 10001-20000, 20001-25000 and more than 25000.Most of the farmers are poor and their monthly income is among 5000-1000.
Fig 2. Monthly income status of respondents
In 2009, temperature was again increased and average temperature was 32.110C. In 2011, temperature was again decreased and average temperature was 31.090C. Again temperature was increased in 2012 and it was around 320C. But in 2013 to 2015, temperature was decreased a little and average temperature was 31.490C, 31.850C and 31.510C respectively. So, average temperature was increases or decreased in the recent years in Paikgacha upazila. It indicates the temperature variation in this area.
Fig 3. Average temperature variation of Paikgacha upazila from the years 1996 to 2015.
Average Dry bulb Temperature
From 1996 to 2015, average dry bulb temperature was about 250C to 27.50C. From Fig. 4, the highest average dry bulb temperature was 27.37 in 2010 and lowest average temperature was 25.280C in 2011. According to the graph, the average dry bulb temperature was increased or decreased in the recent years.
Fig 4. Average dry bulb temperature variation of the Paikgacha upazila
In 2010, it was decreased and the rate was only 312.5 mm. Again it was increased in 2011 and it was 6816.08 mm. In 2014, annual rainfall was a little decreased and it was around 4026.2 mm. So, annual rainfall was decreased or increased in the recent years. It is the result of climate change. Fig. 5 indicates the maximum rainfall of the years 1996 to 2014.
Fig 5. Total annual rainfall of Paikgacha upazila, Khulna(Source: BCAS, 2011).
Bangladesh Centre for Advanced Studies (BCAS), Dhaka, 2011 has reported that 16% of the households cited that less overall rainfall and 4% cited that more overall rainfall. But we found that 27% of the households cited for less overall rainfall and 3% for more overall rainfall.
Fig 6. Maximum annual rainfall of Paikgacha upazila.
Change of Yield of Wheat
From 2012 the rate is again increased. In 1998, 2001, 2003, 2006, 2009, 2012 and 2015, the yield rate was 0.7 MT, 0.82 MT, 0.97 MT, 0.69 MT, 0.71 MT, 0.72MT and 1.04 MT.
Fig 7. Yield Rate of Wheat
Change of Yield Rate of Jute
Jute is Golden fiber for Bangladesh. The nature of Paikgacha is fit for jute yield. There has some species of jute. They are deshi and tosa. In figure the yield rate showing the deshi jute. From 1998 to 2000 the cultivation of jute is seen. But from 2001 to 2012 there have no yield of deshi jute. From 2013 to 2015 the production is again decreased. In 1998 and 2000 the yield rate was 0.54 MT and 2.2 MT. From 2001 to 2012 there was no yield. In 2013, 2014 and 2015 the yield is 0.86 MT, 0.74 MT, and 0.58 MT respectively.
Fig 8. Yield rate of Jute (Deshi)
The cultivation of Tosa jute is seen from 1998 to 2015. Its yield rate is same almost all the years. But in 2015 the production is reduced. In 1998, 1999, 2001, 2007, 2009, 2013 and 2015, the yield rate was 0.87 MT, 1 MT, 0.96MT, 0.99MT, 0.91 MT, 0.92 MT and 0.8 MT respectively.
Fig 9. Production rate of Jute (Tosa)
As the climate change impact cannot be solving completely, we should follow the adaptation measures. Adaptation is to follow some strategy to reduce climate change impacts on crop production. The following recommendation can be followed to improve the impacts of climate change on crop production in coastal region. 1. To stop ingress of saline water into agricultural land, necessary measures must be taken such as buildup sluice gate in every bridge and culvert, embankment of the riverside; 2. For availability of irrigation, rain water should be stored, ponds and lakes should be conserved; 3. Use salinity and flood tolerant seeds; 4. Use optimum amount of organic fertilizers; 5. Cultivate short durational and hybrid crop to increase productivity; 6. Shrimp culture must be stopped in agricultural land; 7. Provide enough healthy seeds and fertilizers from government; 8. Train farmers by agricultural officers to cultivate crops with modern technology; 9. Multi-farming such as paddy, poultry and fish can be a great source of agricultural products, income and it also ensures food security.
The Writer is an Environmental Analyst & Associate Member, Bangladesh Economic Association.