Unprecedented study will estimate carbon stocks in over 600,000 hectares of citrus orchards and native vegetation within Brazilian farms. Area comprises the world's largest citrus belt, and produces 60% of the juice oranges consumed in the planet. The work will encompass a survey of the region's wildlife, an important environmental quality indicator. The project is a partnership between Embrapa and Fundecitrus and is sponsored by the juice and smoothies company Innocent Drinks. Results will show how much carbon Brazilian citriculture stores. Carbon pricing for these conservation areas and other indicators may work as parameters for programs of payment for environmental or ecosystem services. Data will be made available in an online, public-access platform. Embrapa and the Fund for Citrus Protection (Fundecitrus) are initiating this month a joint scientific investigation effort to quantify carbon stocks and identify wildlife in the citrus belt shared by the states of São Paulo and Minas Gerais (Southwest and Triangle regions), the largest of its kind in the world. The project has funded by Innocent Drinks, after being chosen among propositions from several countries as part of the company's Farmer Innovation Fund, offering funding to projects that aim to reduce carbon in agriculture and inspire other farmers to adopt best practices. The work performed in the citrus belt will gather original data on carbon stocks and will encompass both the orange orchards and the designated native vegetation areas within the farms, over a territory of nearly 600,000 hectares. Different methods will be used in the production and in the preservation areas. The first one involves weighing trees, by sampling, to calculate the average amount of carbon that is stored in each tree. They will be weighed on the field, and only after drying, then estimates per plant, per hectare and for the whole citrus belt will be calculated. Leading this part of the project, researcher Carlos César Ronquim, from Embrapa Territorial, previously produced a small survey using a similar method in 2006, in citrus and coffee crops located in the state of São Paulo. Next, the work is to be expanded to gather data on changes in management of citrus crops over the last 15 years, such as tree densification and absence of soil resurfacing at the orchards. “If the plant concentration increases, then there is a lot more carbon per hectare”, foresees the researcher. Data from the Tree Inventory produced by Fundecitrus in 2021 show that production areas alone, where the orange orchards are located, spread over more than 400,000 hectares of the São Paulo- Southwest/Triangle of Minas Gerais citrus belt. This project will make this whole area better known to us, explains Fundecitrus' Orange Production Forecast coordinator, Vinícius Trombin. “We will find out how much carbon the orange trees within the citrus belt sequester, and how much carbon is fixed in the soil and in the native trees at the preservation areas within orange farms”, adds Trombin. Carbon stock is an essential indicator of environmental quality Plants stock carbon in their biomass as they capture CO2 from the atmosphere during photosynthesis. This occurs especially during their growth phase, but goes on, although less intensely, after they reach maturity. “Research has pointed that out, even in the Amazon Rainforest: a perennial, quite mature forest continues to sequester carbon”, says Embrapa's researcher Lauro Nogueira Júnior. Carbon accumulates in the plant's structure (trunk, branches, leaves, flowers, fruits), in the yet undecomposed organic matter on the floor (mulch), in roots and in the soil. Carbon stock is an essential indicator of environmental quality for international forums such as the Intergovernmental Panel on Climate Change (IPCC) and the United Nations Framework Convention on Climate Change (UNFCCC). A periodic follow-up of this indicator shows whether an area is sequestering or emitting carbon dioxide, one of the main greenhouse gases. Mapping, estimation, pricing Areas covered by native vegetation have already been studied by consistent works, which indicate the amount of carbon contained in different types of forest formations. Thus these trees will not need to undergo any weighting or measurements. The team will start by identifying, using satellite images, the state of the vegetation in preservation areas within the citrus belt. The data obtained in this survey will be combined with information about types of vegetation in Brazil, produced by the Brazilian Institute of Geography and Statistics (IBGE). Only then will the amounts of carbon stocked in vegetation areas be calculated. “We will combine information on land use and cover, maps of vegetation types made available by IBGE and secondary data on carbon stocked in different types of vegetation, both in the Atlantic Rainforest and Cerrado”, sums up Nogueira, the project leader. Researchers will also survey the monetary value of carbon in the areas dedicated for preservation. The goal is that this indicator, alongside other data gathered by the whole study, can be used as a parameter for programs of payment for environmental or ecosystem services. Nogueira points out that their idea is to create conditions for this indicator to be acknowledged in citriculture not only as an economic asset but also as an environmental asset. “This may lead to payment for this environmental service, which the orange farm provides, or to conversion to currency in negotiations for better prices in the international market. There is a growing demand for sustainable products, and solid indicators may stimulate the consumption of orange juice among consumers which are more sensitive to such factors”, analyzes Nogueira. For Fundecitrus' general manager, Juliano Ayres, the project will reinforce the importance of a continuous adoption of good agricultural practices. “The newly acquired data will make orange production's environmental dimension clearer and more tangible to farmers, and reinforce how important it is that they continue to conserve the environment; after all, everything is connected and farmers themselves will profit from such conservation in the future”, highlights Ayres. Following footprints Aside from carbon stocks, Embrapa and Fundecitrus will investigate how smaller and larger orange farms may be habitats for wildlife. “Biodiversity is an indicator of environmental quality”, says Embrapa's researcher José Roberto Miranda. He will coordinate an effort to identify vertebrates, especially birds and mammals, living in orange farms. Footprints, nests, burrows, hairs, feathers and feces. These will be the main traces sought by the researchers. Miranda says that in some situations, studying the footprints or feces will be enough to identify the animal that left them. “Animals will be detected and identified mainly through direct observation in field surveys. The use of binoculars helps to see details and identify the species at a distance”, adds Miranda. Observation and traces, as well as reports from people who work on the farms, will also guide the installation of cameras to capture images of the animals, specially those of nocturnal habits. “We were careful to choose the use of non-harmful, non-destructive methods to analyze wildlife”, highlights the researcher. The first step to study the fauna will be to look at satellite images of the target farms and map their land use and cover. Among other factors, it will be important to balance the placement of cameras between production and conservation areas. Another factor to be considered is the behavior of the fauna along the year's different seasons, especially due to variations in moisture and temperature. Some species 'burrow' during colder and dryer months, when their food becomes scarce; others show migratory behaviors. Thus, there is a need to study the environment along different periods over at least one year. Birds are the world's most abundant group of vertebrates, and the researchers expect it to be the most abundant also among the animals observed in the study. Mammals, in turn, although rarer, they offer important hints at the local animal diversity. Most endangered species belong to this group. Also, the presence of an individual member of the large carnivore group indicates the presence of several other species besides its own. “No panther subsists unless there is a whole population of other animals, specially smaller mammals, on which it feeds”, explains Miranda. Sowing aids The presence of fauna is beneficial for citrus farms. Birds, for example, control insect populations, which are vectors for diseases that strike orange trees. In addition, they may work as 'sowing aids' in native vegetation areas undergoing restoration processes, or even in their maintenance. Birds fly to different environments, where they feed and defecate, and by doing so they end up sowing new trees. As for carbon stocks, the project will publish recommendations for farmers about how to foster favorable environments for wildlife. Guaranteeing the presence of plant species that are attractive to birds in preservation areas is one of the means to achieve this goal. “This is Ecology: the science of the interaction between species and environments”, recalls Miranda. Studies on carbon storage and presence of fauna are to be carried out until June 2024. The data surveyed will be made available in an online public-access platform in the form of maps, and will be described in papers submitted to scientific journals. “The results obtained by the project will be made public and available for everyone to use, as long as they cite the source”, highlights Trombin. There will also be recommendations for farmers about how to increase carbon storage and create favorable environments for animals. The data will be grouped by region, and the farms will not be identified. Region produces six out of ten glasses of orange juice consumed in the world The citrus belt ranging from the Southwest/Triangle of Minas Gerais to São Paulo is the main producer of juice oranges in the planet. According to Markestrat data, the industry moves nearly US$ 14 billion per year, which add R$ 2 billion to the Brazilian gross domestic product (GDP), from exports alone. It is responsible for 35% of the world's orange production and 75% of the international orange juice market – six out of ten glasses of the beverage consumed in the world come from the Brazilian citrus belt. Over the last 30 years, due to improved efficiency in the control of pests and diseases, in crop treatments, and in use of technology and densification, the region's average productivity more than doubled - from 330 boxes per hectare in 1988/1989 to 830 boxes on average over the latest six harvests. Planted areas, on their turn, decreased 40%. A survey performed by Fundecitrus based on a method developed by Embrapa also quantified the territory assigned for permanent preservation areas and legal reserves. For every 2.52 hectares of citrus crops in São Paulo and Southwest/Triangle of Minas Gerais, there is 1 hectare dedicated for the preservation of native vegetation, amounting to over 180,000 hectares. These numbers are based on a complete mapping of the citrus belt, produced by Fundecitrus in 2017, and on data from the Brazilian Rural Environmental Registry (CAR). The initiative to calculate carbon stocks and identify wildlife in orange crops is intended to enhance the knowledge available on the relationship between crop and environment. “Through such quantitative data, we want to understand the positive externalities that arise from citriculture. We know how important orange is due to its benefits to human health. We acknowledge this production chain's unique capacity to create jobs and produce economic wealth for the country. Now we will gather data on the role it plays in environmental conservation, which is quite evident but has never been measured to such an extent as that of citriculture nor by any other chain within Brazilian agribusiness”, reinforces Vinícius Trombin, from Fundecitrus.