The FAOSTAT database of greenhouse gas emissions from agriculture

Peer reviewedPublisher PD

A multi-approach software library for estimating crop suitability to environment

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A new cropland area database by country circa 2020

We describe a new dataset of cropland area circa the year 2020, with global coverage and with data for 221 countries and territories and 34 regional aggregates. Data are generated from geospatial information on the agreement–disagreement characteristics of six open-access high-resolution cropland maps derived from remote sensing. The cropland area mapping (CAM) aggregation dataset provides information on (i) mean cropland area and its uncertainty, (ii) cropland area by six distinct cropland agreement classes, and (iii) cropland area by specific combinations of underlying land cover product. The results indicated that world cropland area is 1500 ± 400 Mha (mean and 95 % confidence interval), with a relative uncertainty of 25 % that increased across regions. It was 50 % in Central Asia (40 ± 20 Mha), South America (180 ± 80 Mha), and Southern Europe (40 ± 20 Mha) and up to 40 % in Australia and New Zealand (50 ± 20 Mha), Southeastern Asia (80 ± 30 Mha), and Southern Africa (16 ± 6 Mha). Conversely, cropland area was estimated with better precision, i.e., smaller uncertainties in the range 10 %–25 % in Southern Asia (230 ± 30 Mha), Northern America (200 ± 40 Mha), Northern Africa (40 ± 10 Mha), and Eastern Europe and Western Europe (40 ± 10 Mha). The new data can be used to investigate the coherence of information across the six underlying products, as well as to explore important disagreement features. Overall, 70 % or more of the estimated mean cropland area globally and by region corresponded to good agreement of underlying land cover maps – four or more. Conversely, in Africa cropland area estimates found significant disagreement, highlighting mapping difficulties in complex landscapes. Finally, the new cropland area data were consistent with FAOSTAT (FAO, 2023) in 15 out of 18 world regions, as well as for 114 out of 182 countries with a cropland area above 10 kha. By helping to highlight features of cropland characteristics and underlying causes for agreement–disagreement across land cover products, the CAM aggregation dataset may be used as a reference for the quality of country statistics and may help guide future mapping efforts towards improved agricultural monitoring. Data are publicly available at https://doi.org/10.5281/zenodo.7987515 (Tubiello et al., 2023a).</p

Brazil's agricultural land, cropping frequency and second crop area: FAOSTAT statistics and new estimates.

Resumo: Uma representação acurada do território é crucial para uma avaliação adequada da sustentabilidade da produção de alimentos e bioenergia. No Brasil, três culturas com ambos os usos (soja, milho e cana) ocupam 3/4 da área agrícola do país. A área de uso agropecuário da terra, a frequência de cultivo e a área de cultivo na segunda safra são parâmetros essenciais para um grande número de modelos de uso da terra. Entretanto, os autores detectaram inconsistências nas estimativas da FAOSTAT e da literatura quanto a esses parâmetros. O objetivo deste trabalho é apresentar os resultados de uma iniciativa conjunta entre a Embrapa e a FAO para atualizar esses parâmetros com base em estatísticas oficiais. A atualização dos dados da FAOSTAT levou a uma mudança na área de agricultura e pastagem do Brasil para 63 e 172 Mha em 2016, respectivamente, 28% e 12% menores do que os valores anteriores. Considerando isso, a frequência de cultivo (área colhida sobre área de uso da terra) no Brasil é maior que 1.2, que resulta 30% superior às estimativas atualmente presentes na literatura e à média global. A área de segunda safra em 2017 pode ter alcançado 16 Mha, um aumento de 92% desde 2006. Em 2017, isso representava 21% da área total colhida no país, sendo composta principalmente de milho (68%), trigo (13%) e feijão (6%). Os novos dados têm importantes repercussões para modelos de uso da terra e políticas públicas para a promoção de uma agricultura e bioenergia sustentáveis. -- Abstract: Accurate territory representation plays crucial role in proper food and crop-based bioenergy sustainability evaluation processes. Three crops used for both purposes (soybean, corn and sugarcane) account for 3/4 of croplands in Brazil. Agricultural land, cropping frequency and second crop area are essential parameters for a variety of land-use models. However, the authors of the current study have identified inconsistencies in FAOSTAT and in literature estimates on them. The aim of the current study is to present the results of a joint effort carried out by Embrapa and FAO in order to update those parameters with verified official records. FAOSTAT's updated estimates show that cropland and pasture areas in Brazil back in 2016 covered 63 Mha and 172 Mha, respectively, and these numbers were 28% and 12% lower than previous figures for the same year. Accordingly, cropping frequency (i.e., ratio of harvested area / cropland) in Brazil is higher than 1.2, which is 30% higher than both the currently available estimates and the global average. Second crop area in 2017 may have reached 16 Mha, a 92% increase since 2006. In 2017, it accounted for 21% of total harvested area in the country, which mostly comprised corn (68%), wheat (13%) and bean (6%). The new data presented herein have important repercussions on land-use models and policy design to promote sustainable agriculture and bioenergy production

The impacts of increased heat stress events on wheat yield under climate change in China

China is the largest wheat producing country in the world. Wheat is one of the two major staple cereals consumed in the country and about 60% of Chinese population eats the grain daily. To safeguard the production of this important crop, about 85% of wheat areas in the country are under irrigation or high rainfall conditions. However, wheat production in the future will be challenged by the increasing occurrence and magnitude of adverse and extreme weather events. In this paper, we present an analysis that combines outputs from a wide range of General Circulation Models (GCMs) with observational data to produce more detailed projections of local climate suitable for assessing the impact of increasing heat stress events on wheat yield. We run the assessment at 36 representative sites in China using the crop growth model CSM-CropSim Wheat of DSSAT 4.5. The simulations based on historical data show that this model is suitable for quantifying yield damages caused by heat stress. In comparison with the observations of baseline 1996-2005, our simulations for the future indicate that by 2100, the projected increases in heat stress would lead to an ensemble-mean yield reduction of –7.1% (with a probability of 80%) and –17.5% (with a probability of 96%) for winter wheat and spring wheat, respectively, under the irrigated condition. Although such losses can be fully compensated by CO2 fertilization effect as parameterized in DSSAT 4.5, a great caution is needed in interpreting this fertilization effect because existing crop dynamic models are unable to incorporate the effect of CO2 acclimation (the growth enhancing effect decreases over time) and other offsetting forces

A global FAOSTAT reference database of cropland nutrient budgets and nutrient use efficiency (1961–2020): nitrogen, phosphorus and potassium

Nutrient budgets help to identify the excess or insufficient use of fertilizers and other nutrient sources in agriculture. They allow for the calculation of indicators, such as the nutrient balance (surplus if positive or deficit if negative) and nutrient use efficiency, that help to monitor agricultural productivity and sustainability across the world. We present a global database of country-level budget estimates for nitrogen (N), phosphorus (P) and potassium (K) on cropland. The database, disseminated in FAOSTAT, is meant to provide a global reference, synthesizing and continuously updating the state of the art on this topic. The database covers 205 countries and territories, as well as regional and global aggregates, for the period from 1961 to 2020. Results highlight the wide range in nutrient use and nutrient use efficiencies across geographic regions, nutrients, and time. The average N balance on global cropland has remained fairly steady at about 50–55 kg ha−1 yr−1 during the past 15 years, despite increasing N inputs. Regional trends, however, show recent average N surpluses that range from a low of about 10 kg N ha−1 yr−1 in Africa to more than 90 kg N ha−1 yr−1 in Asia. Encouragingly, average global cropland N use efficiency decreased from about 59 % in 1961 to a low of 43 % in 1988, but it has risen since then to a level of 55 %. Phosphorus deficits are mainly found in Africa, whereas potassium deficits occur in Africa and the Americas. This study introduces improvements over previous work in relation to the key nutrient coefficients affecting nutrient budgets and nutrient use efficiency estimates, especially with respect to nutrient removal in crop products, manure nutrient content, atmospheric deposition and crop biological N fixation rates. We conclude by discussing future research directions and highlighting the need to align statistical definitions across research groups as well as to further refine plant and livestock coefficients and expand estimates to all agricultural land, including nutrient flows in meadows and pastures. Further information is available from https://doi.org/10.5061/dryad.hx3ffbgkh (Ludemann et al., 2023b) as well as the FAOSTAT database (https://www.fao.org/faostat/en/#data/ESB; FAO, 2022a) and is updated annually.</p

The environmental impact of fertilizer embodied in a wheat-to-bread supply chain

Food production and consumption cause approximately one-third of total greenhouse gas emissions, and therefore delivering food security challenges not only the capacity of our agricultural system, but also its environmental sustainability. Knowing where and at what level environmental impacts occur within particular food supply chains is necessary if farmers, agri-food industries and consumers are to share responsibility to mitigate these impacts. Here we present an analysis of a complete supply chain for a staple of the global diet, a loaf of bread. We obtained primary data for all the processes involved in the farming, production and transport systems that lead to the manufacture of a particular brand of 800 g loaf. The data were analysed using an advanced life cycle assessment (LCA) tool, yielding metrics of environmental impact, including greenhouse gas emissions. We show that more than half of the environmental impact of producing the loaf of bread arises directly from wheat cultivation, with the use of ammonium nitrate fertilizer alone accounting for around 40%. These findings reveal the dependency of bread production on the unsustainable use of fertilizer and illustrate the detail needed if the actors in the supply chain are to assume shared responsibility for achieving sustainable food production

Increased nitrogen enrichment and shifted patterns in the world's grassland: 1860–2016

Production and application to soils of manure excreta from livestock farming significantly perturb the global nutrient balance and result in significant greenhouse gas emissions that warm the earth's climate. Despite much attention paid to synthetic nitrogen (N) fertilizer and manure N applications to croplands, spatially explicit, continuous time-series datasets of manure and fertilizer N inputs on pastures and rangelands are lacking. We developed three global gridded datasets at a resolution of 0.5∘&thinsp;×&thinsp;0.5∘ for the period 1860–2016 (i.e., annual manure N deposition (by grazing animals) rate, synthetic N fertilizer and N manure application rates), by combining annual and 5&thinsp;arcmin spatial data on pastures and rangelands with country-level statistics on livestock manure, mineral and chemical fertilizers, and land use information for cropland and permanent meadows and pastures. Based on the new data products, we estimated that total N inputs, the sum of manure N deposition, manure N application and fertilizer N application to pastures and rangelands, increased globally from 15 to 101&thinsp;Tg&thinsp;N&thinsp;yr−1 during 1860–2016. In particular during the period 2000–2016, livestock manure N deposition accounted for 83&thinsp;% of the total N inputs, whereas manure and fertilizer N application accounted 9&thinsp;% and 8&thinsp;%, respectively. At the regional scale, hotspots of manure N deposition remained largely similar during the period 1860–2016 (i.e., southern Asia, Africa and South America); however, hotspots of manure and fertilizer N application shifted from Europe to southern Asia in the early 21st century. The new three global datasets contribute to the filling of the previous data gaps of global and regional N inputs in pastures and rangelands, improving the abilities of ecosystem and earth system models to investigate the global impacts of N enrichment due to agriculture, in terms of associated greenhouse gas emissions and environmental sustainability issues. Datasets are available at https://doi.org/10.1594/PANGAEA.892940.</p

Feasible mitigation actions in developing countries

Energy use is not only crucial for economic development, but is also the main driver of greenhouse-gas emissions. Developing countries can reduce emissions and thrive only if economic growth is disentangled from energy-related emissions. Although possible in theory, the required energy-system transformation would impose considerable costs on developing nations. Developed countries could bear those costs fully, but policy design should avoid a possible 'climate rent curse', that is, a negative impact of financial inflows on recipients' economies. Mitigation measures could meet further resistance because of adverse distributional impacts as well as political economy reasons. Hence, drastically re-orienting development paths towards low-carbon growth in developing countries is not very realistic. Efforts should rather focus on 'feasible mitigation actions' such as fossil-fuel subsidy reform, decentralized modern energy and fuel switching in the power sector