How much fertilizer is the appropriate amount to ensure that crop production can meet local and global food security needs while limiting damage to the environment?
Answering this question remains a major challenge, but it can be better explored with the new and robust data available in the FAOSTAT database, according to the Food and Agriculture Organization of the United Nations (FAO).
FAOSTAT is a joint effort by the Food and Agriculture Organization and the International Fertilizer Association (IFA), in collaboration with leading scientists and experts at the University of Maryland Center for Environmental Sciences, the Swedish University of Agricultural Sciences, CEIGRAM-Universidad Politécnica de Madrid, Wageningen University & Research, University of Nebraska and the African Institute of Nutrition the plant.
The partnership has led to the development of new data on agricultural land nutrient budgets, FAO said, allowing an assessment of the environmental burden of fertilizer inputs in relation to amounts needed to support sustainable crop production.
The agri-nutrient budget is a new data domain for FAOSTAT, the world’s largest portal for food and agricultural statistics, serving as a global public good allowing Member Nations and all stakeholders in global agri-food systems access to harmonized data on production, trade and consumption – and now flows of nitrogen, phosphorous and phosphate, the nutrients The three main plants that crops need to thrive.
FAO takes basic crop and livestock production data provided by countries as part of their international reporting obligations, and combines them with methods and models provided by scientific partners in this project, to generate a common set of reference data, by country, over time – 1961-2020 series ; which will be updated annually. FAO’s Chief Statistician Francesco Tubilo explained that FAOSTAT data represents a powerful data tool, building on core national statistics to help segregate challenging sustainability issues such as nutrient fluxes, at country, regional and global levels.
Nutrient budgets in agricultural land
Nutrient balances in agricultural lands are an important indicator of nutrient fluxes that can indicate insufficient or excess use of agricultural inputs in the form of the three main nutrients for plant growth, whether in mineral, chemical or organic form.
The budget approach measures amounts of mineral and chemical fertilizers and manure applied to farmland soils along with biological nitrogen fixation—legumes are great nitrogen fixers—and atmospheric deposition, and subtracts the nutrient flux associated with crop harvesting.
In principle, nutrient overloads in soils (budget surplus) present environmental risks such as leaching into water sources and volatilization in the form of greenhouse gas emissions. On the other hand, inadequate food loads (budget deficits) are often associated with low crop yields and depletion of soil nutrients.
Budgets can also be converted into efficiency rates, which are a measure of how well crops use available nutrients (the ratio between nutrient removal from crops and total nutrient input). However, the data shows that the results reflect underlying issues that must be dealt with carefully. Seemingly impressive use-efficiency rates, for example, could actually indicate soil nutrient mining, an unsustainable situation in which inadequate inputs, applied relative to required crop production levels, impoverish future production prospects.
At the global level, in 2020, 85 million tons of nitrogen (N), 7 million tons of phosphorus (P) and 12 million tons of potassium (K) were distributed to agricultural lands, a fourfold increase since 1961, with a higher share . of synthetic fertilizers. Nitrogen, phosphorous and potassium were distributed at average rates of 54, 4 and 7 kg/ha, respectively. Compared to the 1960s, these application rates represent a 3.4-fold increase for N, stability for P and a 36% decrease for K. Efficiency rates for all three have increased in recent decades, and have averaged between 50 and 62% over the entire time period.
Nitrogen use efficiency values in Africa clearly indicate that agricultural practices generally mine natural soil nutrients for crop production.
China and India have some of the highest N budget surpluses in the world, with efficiency rates below the global average of 50 percent. Much smaller surpluses are found in Brazil and the USA, in part due to the large-scale cultivation of soybeans, which require lower inputs in those countries due to the natural supply of biological nitrogen from this crop.
Some countries have surpluses of one key nutrient and large deficits of another, including major agricultural countries such as Argentina, Nigeria and Ukraine. This could suggest rebalancing strategies based on crop selection and fertilizer priorities, explains Nathan Wanner, an FAO statistician who helped build the new database.
sustainable agriculture goals
The Food and Agriculture Organization said that a better understanding of agricultural land’s nutrient budgets can help farmers and policy makers better identify and assess practices towards more sustainable farming.
The Food and Agriculture Organization is the custodian of the SDG 2-4-1 indicator, which tracks the proportion of the area under productive and sustainable agriculture.
New Cropland Nutrient Budget data provides a way to go beyond raw benchmarks based on fertilizer application rates as a simplified criterion. While policymakers may disagree about the trade-offs between fertilizer input use, food production needs and environmental protection, the new data provide a more balanced and complete way to understand the interaction between each component in determining nutrient fluxes and thus better define beneficial strategies.