Soil acidity in the farmlands of northern region is increasing at an alarming rate, posing a serious long-term threat to crop production and food security, agricultural experts warned at a seminar in Rajshahi on Saturday.
To address the growing problem, experts emphasized the proper use of lime and dolomite to neutralize soil acidity, alongside efforts to increase organic matter content to restore and maintain soil health.
The observations were made at a day-long seminar titled “Acid Soil Management through Lime Technology and Organic Matter: The Soul of Soil,” organized by the Rajshahi office of the Soil Resource Development Institute (SRDI) at the conference room of the Fruit Research Center in Rajshahi.
The seminar's chief guest was Professor Golam Hafiz Kennedy, Secretary General of the Bangladesh Agricultural Economists Association and Professor at Bangladesh Agricultural University. The event was chaired by Dr. Afsar Ali, Director General of SRDI.
Special guests included Joynal Abedin, Director of SRDI’s Analytical Services Wing, and Dr. Md. Azizur Rahman, Additional Director of the Department of Agricultural Extension (DAE). Professor Dr. Md. Mahmudul Hasan of the Department of Agronomy and Agricultural Extension at the University of Rajshahi participated as a discussant.
The keynote paper was presented by Dr. Nurul Islam, Principal Scientific Officer of SRDI’s Rajshahi Divisional Office, and A.K.M. Aminul Islam, Principal Scientific Officer of the Rajshahi Divisional Laboratory. The paper highlighted the causes of soil acidification, its impact on crop productivity, and the effectiveness of lime technology in mitigating the problem.
Speakers noted that crops require 17 essential nutrients for healthy growth. While carbon, oxygen, and hydrogen are obtained from air and water, the remaining nutrients must come from the soil. These nutrients are most readily available when soil pH ranges between 5.6 and 7.3.
However, large areas of agricultural land in northern Bangladesh have become excessively acidic, resulting in deficiencies of phosphorus, calcium, magnesium, and molybdenum. Increased soil acidity also intensifies the toxic effects of aluminum and iron, negatively affecting crop growth and yields.
Researchers explained that the required rate of dolomite application depends on soil pH, organic matter content, and soil texture. Generally, farmers can apply between 3 and 10 kilograms of dolomite per decimal of land, with lower rates recommended for sandy soils and higher rates for clay soils. Proper application helps reduce acidity and creates favorable conditions for nutrient uptake.
The speakers also stressed the importance of organic matter, describing it as the “soul” of soil. They noted that declining organic matter levels reduce soil fertility and water-holding capacity. Soil structure and productivity can be improved through the application of cow dung, compost, vermicompost, and green manure.
Experts urged farmers to reduce excessive dependence on chemical fertilizers and adopt soil-test-based applications of lime and organic fertilizers to ensure sustainable agricultural production.
They also called for stronger coordination among SRDI, the Department of Agricultural Extension, and agricultural research institutions to promote soil health management practices.
Participants agreed that maintaining healthy and productive soils is essential for combating the adverse impacts of climate change and ensuring long-term food security. They concluded that integrated and immediate action is needed to restore and preserve the “soul” of the soil.
