An Innovative Solution for Agriculture Optimization | Daily News
Smart Fertilizers:

An Innovative Solution for Agriculture Optimization

PART 1 :

The Government’s recent ban on chemical or inorganic fertilizers commonly utilized by the farming community in Sri Lanka has generated varied views and discussions among Sri Lankan agricultural experts, politicians, the farming community and the public. The policy is to ban all types of inorganic fertilizers and use only organic fertilizers for all major crops in Sri Lanka.

President Gotabaya Rajapaksa and leading health experts believe that the pollution of the ground water, lakes and canals caused by leaching of chemicals due to the usage of traditional soluble NPK (nitrogen, phosphorus and potassium) fertilizers, has resulted in a high incidence of kidney disease and other ailments within the population.

The long-term benefits of the successful implementation of such a policy are many. Besides addressing the current alarming increase in non-communicable diseases (NCDs) among the population, there will be improvements in the nutritional quality of food products for domestic consumption, improvements in the fertility of the arable soil and cleaner water systems thereby improving fish and wildlife habitats, as well as savings in foreign exchange spent on chemical fertilizer imports.

There are, of course, various challenges that will need to be planned for and dealt with. These include decreases in yields per acre threatening food security in the short term, escalations in logistics and labour costs because of the much larger bulk of organic fertilizer dosage that will be needed, the high import costs of organic fertilizer that will be needed before domestic production capacity can be built up, initial negative impacts on the ability to meet demand for top quality tea export brands resulting in the loss of competitive edge in existing export markets thus resulting in loss of foreign exchange earnings.

Smart Fertilizers are a comprehensive solution for managing fertilizer utilization for any crop, under any conditions, taking into account the multiple dynamic factors required in optimizing fertilizer use. Smart Fertilizers enable growers to increase yield, with an order of magnitude lesser dosage, with simple one-time application, while also addressing the issue of fertilizer misuse that results in waste, soil damage, and groundwater contamination. Smart Fertilizer manufacture requires standard and easily available inputs. If Sri Lanka can build up capacity to manufacture Smart Fertilizers domestically, this would result in drastic reductions in foreign exchange requirements.

But first, a quick review of the basics.

The objective of this article is to study the fertilizers in general to understand the various issues related to organic and inorganic fertilizers and to present a new Smart Fertilizer which is insoluble in water, eco-friendly and mimics the natural fertilizer in fertile soils. Hence, there will be no leaching of chemicals to ground water, and run off to canals and waterways. Further, the new Smart Fertilizers have the added advantage of reduced utilisation (dosage) as compared to the traditional NPK fertilizers, while still resulting in increased yield and, therefore, improved return on investment for the farmer.

What are plant or crop fertilizers?

Fertilizers are plant nutrients required for crops to grow. Crops need energy (light), CO2 (carbon dioxide), water and minerals to grow. Crops acquire the carbon they need from the CO2 absorbed through the leaves; and they absorb water and plant nutrients from the soil. Plant nutrients are building blocks of crop material. Mineral fertilizers provide plant nutrients for crops. Without nutrients, the crops cannot grow.

Nutrients are classified into three sub-groups based on plant growth needs:

Primary Nutrients - NPK

* Nitrogen (N), the main constituent of proteins, is essential for growth and development in plants. Supply of nitrogen determines a plant’s growth, vigour, colour and yield.

* Phosphorus (P) is vital for adequate root development and helps the plant resist drought. Phosphorus is also important for plant growth and development, such as the ripening of seed and fruit.

* Potassium (K) is central to the photosynthesis of crops. Potassium helps improve crop quality and crop resistance to lodging, disease and drought. In addition, the secondary nutrients sulphur, magnesium and calcium are required for optimum crop growth.

Secondary Nutrients are required for optimum crop growth

* Sulphur is especially important in the initial growth stages, to produce essential amino acids, proteins, and oils.

* Magnesium is needed for photosynthesis, converting light into chemical energy for nutritional purposes.

* Calcium is particularly important for the yield, quality and shelf life of fruit and vegetables.

Micronutrients are essential trace elements.

* Zinc (Zn) is the most important.

* Others include Chlorine (Cl), Iron (Fe), Manganese (Mn), Boron (B), Selenium (Se), Copper (Cu), Molybdenum (Mo), etc.

Each plant nutrient has unique physiological functions which cannot be replaced by any other nutrient.

Crop growth is limited by the most deficient nutrient. And, therefore, all nutrients are important.

The ‘law of minimum’ is often illustrated with a water barrel, with staves of different lengths. The barrel’s capacity to hold water is determined by the shortest stave. Similarly, crop yields are frequently limited by shortages of nutrients or water. Once the limiting factor (constraint) has been corrected, yield will increase until the next limiting factor is encountered.

Yield responses to nitrogen are frequently observed, as N is often the most limiting factor to crop production, but not the only one. Balanced nutrition is required to obtain maximum yield and avoid the adverse effects of the shortage of any nutrient.

Among the plant nutrients, nitrogen is most important for higher crop yields.

Nitrogen is the most important primary nutrient, accounting for 57 percent of total consumption. Phosphorus (phosphate) and potassium fertilizers are primarily applied to improve crop quality. Annual application is not always needed, as the soil absorbs and stores these two nutrients for a longer period compared with nitrogen.

Nitrogen must be applied every year to maintain yield and biomass. Phosphate and potash fertilizers are supplied by a small number of large industry players, as phosphate rock and potash mineral deposits are only available in certain regions of the world, while nitrogen fertilizers are produced in many countries, reflecting the wide availability of key raw materials – natural gas and air, needed for its production on an industrial scale. The global nitrogen market is, therefore, less consolidated, but some regions such as Europe and the US have seen significant restructuring of their nitrogen industries in the last decade.

Organic fertilizers supply the same inorganic molecules to crops as mineral fertilizer.

Crops can be fed with mineral or organic fertilizers (manure), and in both cases the crop will utilize the same inorganic molecules. A complete nutrient programme must take into account soil reserves, use of manure or fertilizers, and an accurate supplement of mineral fertilizers.

Organic fertilizers contribute to build up the organic content of soil and at the same time support beneficial micro flora (e.g., bacteria) to grow on plant roots. The efficiency of organic fertilizer is dependent on the bacteria content in the soil. Bacteria decompose the organic content in manure and supply the minerals as nutrients for plant growth. But the quality and quantity of nutrient supplied to plants via this process is inconsistent and is very much dependent upon climatic factors. Plant productivity achieved by supplying only organic matter is low compared with mineral nutrients supplied in the form of fertilizers.

The separation of livestock and arable farming regions has led to nutrient distribution inefficiency, with a surplus in the animal farming regions. The low nutrient content and bulky nature of manure makes transportation inconvenient and costly.

A lifecycle perspective on fertilizer is important

Lifecycle analysis of fertilizers determines the greenhouse gas emissions and absorptions in fertilizer production, transportation and storage, as well as during application and crop growth. When new acreage is converted to cropland, above ground carbon is immediately removed, whereas carbon stored in the ground will leak out more gradually and is converted to CO2. With the ambition to minimize total carbon footprint from global biomass production, efficient use of land, based on modern agricultural practices, is of great importance. Intensive farming with high yields contributes to preserve forests, which are the real ‘carbon sinks’. Organic farming with low yields tends to increase deforestation and emissions. Different fertilizer types have different carbon footprints. Urea emits less CO2 during production than nitrates, but upon spreading, the situation is reversed since urea releases the CO2 contained in its molecule. Urea also often releases more N2O during farming.

The lifecycle carbon footprint is, therefore, higher for urea than for nitrates.

(To be continued…)


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