Salinity Impacts On Potato Yield
The water level drops up to 240 km during the dry season in western part of Bangladesh that causes severe saline problem in 30 Upazilas in Bangladesh. In fact, sea level rise would produce salinity impacts in surface water, ground water and soil. Experts opined, 10% more land will be saline affected and intensity will be increased by 10% in the next decade. Soil salinity can decrease crop production. In future, the transplanted Aman crops area will cover only 18 to 20% on account of high salinity. Paikgachha is an upazilla of Khulna District in the Division of Khulna, Bangladesh. It is located between 22Â°28' and 22Â°43' north latitudes and between 89Â°14' and 89Â°28' east longitudes. The upazila is bounded on the north by Tala upazila of Satkhira zila and Dumuria upazila, east by Shibsa river, Batiaghata and Dacope upazilas, south by Koyra upazila and west by Tala and Assasuni upazilas of Satkhira zila. The upazila occupies an area of 411.19 sq. km. The upazila consists of 1 paurashava, 9 wards, 11 mahallas, 10 unions, 166 populated mauzas and 212 villages. The average population of each ward and mahalla are 1780 and 1456 respectively. On the other hand, the average size of population of each union, mauza and village are 23197, 1397 and 1094 respectively.
The mentioned 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.
Saline water ingress into the agricultural land when there is high tide from river. Soils contain some water soluble salts. Plants absorb essential plant nutrients in the form of soluble salts, but excessive accumulation of soluble salts, which is called soil salinity, can hinder the normal growth of plants. Salts in the soils occur as ions. Ions are released from weathering minerals in the soil. The saline soil suppress the growth of plant. So people lost their interest to crop cultivation due to excessive saline water and soil salinity. Yield rate is very poor in this area. People get only 480-560 kg per bigha paddy from saline tolerance seeds where the possible amount is 800-900 kg per bigha because of saline soils and extreme weather conditions. Water melon is a fruit of summer. It can remove thirst easily. The production of water melon is increased from 1998 to 2008 in Paikgacha. But from 2009 to 2012, the production rate is decreased. Then again from 2013 to 2015 the production rate is increased again. As, the production of water melon is increased day by day, its cultivation is also increasing. Water melon cultivation is increased in the study area because this fruit grow well in saline areas than other agricultural production.
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. There are so many adaptation techniques are followed in crop production. For instance, cultivating salinity tolerant and hybrid crops; making of embankments; changing cropping pattern; using enough fertilizer and modern agricultural technology. But farmers need high training on agriculture, knowledge of actual amount of fertilizers, right use of seeds and irrigation facilities. 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.
(Mr. Reza is an environmental analyst and Associate Member, Bangladesh