When repeated cropping and production on the same soil increases, the soil’s nutrients decrease. The use of chemical fertilizers to increase production from the same land in a short period of time has increased.
Kathmandu: There is a shortage of chemical fertilizer in the country as the contractor company could not import fertilizer on time. As an alternative, the government has asked the Bangladesh government for urea fertilizer.
Even though the government has purchased manure from third countries and distributed it now, farmers have not been able to get as much manure as they want. Farmers have to wait in line for hours to get 15 kg of urea fertilizer.
According to Bholaman Singh Basnet, former chief agricultural crop officer of Nepal Agricultural Research Council (NARC) and paddy expert, farmers apply urea fertilizer on paddy twice. He said that urea fertilizer is being applied 20 to 25 days after transplanting and at the time of ear emergence. “Now is the time to plant ears in paddy. This is the time when there is a scarcity of manure,” he said.
Why is urea used in paddy?
Green plants and vegetation are productive while humans and other organisms are consumers. According to Emeritus PK Jha, a professor at the Central Department of Botany, Tribhuvan University, plants needs nutrients just like humans. He said that nitrogen, phosphorus, and potassium are essential nutrients that plants need for growth and development.
Shriprasad Bhandari, senior scientist at the National Soil Science Research Center, Nepal Agricultural Research Council, Nark, said that farmers are attracted to chemical fertilizers as they contain more nutrients than organic fertilizers. One kg of urea contains 46 percent nitrogen. But that doesn’t happen in organic manure, ‘he said,’ because farmers use the same amount of nitrogen in the chemical than in the organic manure. ‘ According to him, farmers are attracted to chemical manure as the amount of nitrogen in organic manure is very low.
Nitrogen plays a role in making all plants green, not just rice, said Professor Jha. Phosphorus helps plants in photosynthesis, respiration, energy consumption, cell division, fruit and flower development as well as root development. Potassium plays a role in the formation of proteins, enhances immunity, and the development of parts.
According to agronomists, farmers use urea especially to make paddy green and increase production. As urea increases the amount of chlorophyll in the plant, the crop becomes green. Due to which the photosynthesis process goes well. Bhandari says, ‘Urea is also used in all types of crops as it has a pH value of 7 which is neutral. According to rice expert Basnet, urea needs to be added again and again as urea flows in wet and watery areas and the nitrogen compounds there will evaporate quickly.
Due to this increased consumption
When the order of repeated cropping and production on the same soil increases, then the nutrients found in the soil decrease. According to Professor Jha, fertilizers will be used to increase fertility after the nutrients in the soil are automatically depleted after starting production from the same land three times a year.
Chemical manure dissolves easily in water and organic manure does not dissolve, says Dinesh Khadka, a scientist at Nark’s Soil Science Research Center. “The purpose of both fertilizers is the same, to provide the nutrients needed by the plants,” he said. “Chemical fertilizers are made from chemical processes and organic fertilizers from organic matter.”
The use of chemical fertilizers has also increased due to the habit of looking for quick results. Bhandari said that the use of manure is increasing as farmers have to produce enough for others. ‘The more a crop produces, the more fertilizer it needs. It is natural to use urea after applying fertilizer and giving results, ‘he said.
Arun GC, Agriculture Extension Officer at the Ministry of Agriculture and Livestock Development, says that farmers are attracted to chemical fertilizers as they give more results than organic ones. “Farmers have started using it as more organic manure gives less yield and even less chemical manure gives more yield,” he said. According to agronomists, one kg of urea will increase the production of paddy by another 12 to 20 kg.
Krishna Poudel, an agronomist, said that the use of chemical fertilizers has increased as the land does not grow but the population grows. ‘Urea is used in paddy. But it does not produce the required amount. The main purpose of urea is to make it green. If it is not used properly during sowing, all the paddy will be destroyed.
Decreasing soil fertility
According to agronomists, the use of too many chemical fertilizers in the field can lead to problems such as loss of soil fertility and high acidity. According to the data of the World Bank in 2016, 74 kg of chemical fertilizer is being used in every 1 hectare of land in Nepal.
Poudel, an agronomist, says that using too much chemical fertilizer will reduce soil fertility and affect crops. He argues that the quality of food and crops produced by adding chemical fertilizers is not good. He said that the use of fertilizers has been increasing as proper care is required for the production of improved varieties of crops.
Dinesh Khadka, a scientist at the Soil Science Research Center in Nark, says that the high acidity of the soil reduces the number of nutrients and minerals there. He said that the required amount of fertilizer has not been applied to the crops by the farmers in Nepal and this will not lead to a dire situation right now. Research has shown that the overuse of manure can affect aquatic diversity. Poudel, an agronomist, says that synthetic urea leaves unwanted compounds in the soil and kills micro-organisms.
Although the use of chemical fertilizers in Nepal has not shown any reduction in fertility, the data shows that the quality of soil and nutrients required in the soil is lacking in some places.
More incentives for chemical fertilizers
Nepal has been importing chemical fertilizers from India and Russia since the 1950s, said GC. Its use has skyrocketed since the government started giving subsidy to manure in 1973/74. Although the grant was stopped in 1997/98, the use increased after the government resumed the grant from 2008/09. In this too, the use of potash, DAP, and urea by the government has been reduced while the use of other essential nutrients required by the plants has been declining.
In the last five years, the government has spent about Rs 50 billion for the purchase of manure alone. The government has allocated Rs 11 billion for the purchase of chemical fertilizers for the current fiscal year, said GC. While Rs. 430 million has been allocated for the purchase of organic manure. He said that the demand for urea, potash, and DAP fertilizer in Nepal is around 700,000 metric tonnes per annum but there is no supply accordingly. He informed us that the country is currently importing around 400,000 metric tonnes annually.
In the previous fiscal year, the government had allocated Rs 9 billion for the purchase of chemical fertilizers, but when the amount was insufficient, an additional Rs 1.68 billion was spent on importing Rs 10.68 billion. The government has spent Rs. 45.09 billion for chemical fertilizers in the last five years including the current fiscal year. 5.44 billion in FY 2012/13, Rs. 4.80 billion in FY 2013/14 and FY 2013/14. 8 billion 370 million in 075/76 and 10 billion 680 million in 076/77 for the purchase of chemical fertilizers, said GC.
The government has only programs for organic farming and fertilizer use. According to agronomists, the Ministry of Agriculture has not been able to come up with innovative activities that will directly benefit the farmers. An official of the ministry says that the budget will not reach the hands of the farmers even if the organic manure improvement program is in operation.
What about options?
According to Bhandari, a senior scientist at the Center for Soil Science Research, it is difficult to find soil in Nepal without chemical fertilizers. When crops are planted in every season, a lot of nutrients are depleted from that soil. That is why the use of chemical fertilizers is increasing. He said that there is no need for fertilizer for indigenous crops as the soil of Nepal is suitable. ‘Fertilizer is not required for Kodo crop as it is suitable with Nepali soil. But it is necessary to start using its hybrid. Hybrids and other varieties were also brought in the paddy, the need for fertilizer has been seen after displacing the natives, ‘he said.
He pointed out the need for fertilizer as hybrid and improved varieties are being used more than the native varieties of paddy, maize, and wheat. Experts say that the fertility of the soil decreases accordingly after planting improved varieties of seeds and crops. Krishna Poudel, an agronomist, says that even though fertilizer is needed for modern farming, now the focus should be on organic. Professor Jha says that the current crop has been ‘adopted’ with chemical fertilizers. He says, ‘We also had native crops. But they also started using chemical fertilizers saying it was a nutrient. Eventually, we could not produce without debris. ‘
Basnet, a paddy expert, suggests using green manure as an alternative to urea in paddy. He said that soil fertility should be good for paddy cultivation. He said that plants of Rostata species can be used as green manure in paddy. He said that fertility would be developed by sowing such seedlings a few months before planting paddy and uprooting them in the same soil.