The Sri Lankan government is determined to make farmers immediately switch over to organic farming citing health and environmental reasons as well as the severe foreign exchange shortage which impairs the import of chemical fertilizers. The annual fertilizer import bill is over US$ 400 million.
The government has turned a deaf ear to fervent pleas from agricultural scientists and economists for a “step by step” approach to the change-over and the adoption of mixed fertilizer use policy, where in chemical and organic fertilizers will be used in combination in a judicious and scientific manner, keeping in view both health and economic needs.
It has ignored the argument that an overnight change would be impossible to implement and that the change-over itself could, in fact, hurt agriculture instead of fostering it.
The ban on chemical fertilizer imports was slapped at the time when food prices were rising due to disruptions caused by lockdowns and movement restrictions brought about to contain the COVID-19 pandemic. There is no early chance of these restrictions being lifted.
The Sri Lanka Agricultural Economics Association (SLAEA) had warned that a complete switch–over will result in a 25% fall in paddy yield and the profitability of paddy farming will be reduced by 33%. Coconut yield will be down by 30%. On the other hand, a mixed conventional-organic system will increase paddy profitability by 16%. A switch–over at this juncture will see also tea productivity going down by 35%, and decrease the tea export volume from 279 million kg to 181 million kg.
These are important facts, given that 72% of the Lankan labor force is in agriculture and food security without imports is still a far cry in Sri Lanka.
Despite the quadrupling of the global organic food retail sales reaching US$ 82 billion in 2015, organic farming is not a rage or even significant in the world at large. According to the World of Organic Agriculture 2018 Summary, there were only 57.8 million hectares of organic agricultural land in 2016, including “in-conversion” areas. This was only 1.2 % of the total farmland.
In their paper on the world organic farming scene in the journal Review of Resource Economics (October 2018), Eva-Marie Meemken and Matin Qaim of Gottingen University in Germany attributed the minuscule percentage under organic farming to lower yields. Across all crops, the gap in the yield of organic agriculture ranges between 19 and 25%.
Lack of Nutrients
Nutrient limitations are an important factor making organic agriculture show lower yields. Organic systems are often found to be limited in nitrogen and phosphorus. The release of plant-available nitrogen from organic sources is slow and can often not keep up with the nitrogen demand during peak crop growth periods, the authors point out. The amount of phosphorus provided in organic systems is also sometimes insufficient to replenish the quantities lost due to harvest.
Organic systems are more susceptible to pest outbreaks because of the ban on the use of chemical pesticides. And since chemical weedicide cannot be used in organic farming, weeding has to be done one manually and that is both labor-intensive and expensive. And labor is indeed expensive in Sri Lanka
However, in terms of water availability and use, organic systems tend to have an advantage because soils managed with organic methods show better water-holding capacity and higher rates of water infiltration, the authors point out. “This is also one reason why organic systems are often said to be more resilient and have higher yield stability, even under drought conditions,” the authors say.
Production costs in organic farming being higher, there will be increases in consumer prices, making food less affordable for the poor in developing countries. On an average, organic products are 50% more expensive than conventional products, the authors say. Therefore, the universal goal of giving the masses food security will not be achieved. To feed the hungry, global agricultural production will have to increase by at least 60% and possibly up to 100% by 2050, the authors say. A 100% switch over to organic agriculture will retard progress towards the goal of ensuring food security for all.
Organic Fertilizers Could Also Pollute
Sri Lankan soil scientist Dr.Warshi S. Dandeniya and her collaborator Serene Caucci, say in their paper: Composting in Sri Lanka: Policies, Practices, Challenges, and Emerging Concerns. (www.link.springer.com) that organic fertilizers are not as clean and non-polluting as claimed. They could also pollute the soil. The scientists point out that organic fertilizers commonly called ‘compost’ can be carriers of potentially toxic trace elements.
“Producing good-quality compost, safe for human health and the environment, is a challenge that should be addressed at various levels: from production to policymaking. The long-term use of compost in large quantities and/or application of poor-quality compost to soil can deteriorate environmental quality and pose a threat to the safety of food,” they warn.
“The progressive accumulation of toxic trace elements such as lead and cadmium in soils has been reported in several studies where there has been a long-term application of compost produced from Municipal Solid Waste (MSW). Contamination of food items with potentially toxic trace elements and human pathogens due to the application of compost to crops has been reported in the literature on the subject,” Dandeniya and Caucci point out.
Poultry litter/manure is a source of antibiotic resistance determinants and, therefore, imposes a “silent threat” to environmental quality and health, they say. And night soil (human faeces) could also get mixed up with organic fertilizer. Furthermore: “Organic pollutants such as detergents and antibiotic resistance determinants and pathogens surviving in night soil and septic waste, and the fate of these constituents during composting, have not been studied extensively in Sri Lanka,” they say.
The soil scientists also warn that microbial pathogens and parasites could spread in the environment through creatures likes flies and dogs found at the composting sites.
“Bio-aerosols and volatile compounds could enable transmission from composting sites to other environments with the wind. Leachates coming out from compost piles during the production process, and runoff water from the composting sites, could contaminate both surface and groundwater,” Dandeniya and Caucci warn.
Andante Hadi Pandyaswargo, Dickella Gamaralalage and Jagath Premakumara went into the question of financial sustainability of modern composting in the developing countries of Asia in their 2014 paper published in the International Journal of Recycling of Organic Waste in Agriculture. Their study found that the viability of composting plants depended on the selection of suitable processing methods, the technology used, the scale of the operation, the quality of the product, and marketing strategies.
In the developing countries, where Municipal Solid Waste is mostly organic waste, it is not properly segregated. But compost plants are highly sensitive to input quality. They are best used to treat animal manure, kitchen and agricultural waste because of the uniformity and purity of the organic content, the authors say.
Generally the application of compost technology has not been very successful in Asian cities because segregation of ‘waste-at-source’ is poor in these cities, the authors say. The raw garbage here is full of contaminants such as heavy metals, glass, inert materials, and plant and animal pathogens. Larger scale composting plants receive a large volume of mixed waste with contaminants, the authors point out.
Therefore, the scientific use of the solid waste becomes a tedious process. Landfilling is resorted to as the easy way out. However, the landfills in the under-developed countries are poorly designed and maintained. They are a serious threat to public health. The landfills also cause global warming because organic waste is the main source of methane gas emissions.
Then the authors refer to some key technical issues facing the compost making industry. They say that large-scale composting facilities with complex mechanical pre-processing to remove non-compostable materials have largely failed because there is hardly any mechanical system which can adequately identify and separate all of the materials in the mixed waste to ensure production of good-quality compost.