Agroecological Zoning is a technical-scientific instrument built from the knowledge of environmental capability and vulnerabilities of a particular region, especially regarding the behavior and characteristics of climate, soil, vegetation, geomorphology, and focusing on the land capability for agricultural use. It also considers the social and economic characteristics of each region.
As an instrument for spatial planning of agricultural production, it delimits agroecological zones, which are homogeneous areas, or environmental units, or even basic working units for agriculture. Thus, for each delimited area you can determine a set of general and specific guidelines that will direct public policies and land use actions.
AEZ is a dynamic tool, and should be improved by adding new information according to environmental, socioeconomic, political and technological conditions.
Its main objective is to provide subsidies to agricultural research, technical assistance and rural extension, and also to guide decision makers in establishing public policies in agricultural development programs.
It is usually a demand of the government, but also of other sectors of agricultural production, especially farmers and insurance companies (public and private ones), who see in the Agroecological and Climate Risk Zoning an alternative to reduce risks in agriculture and consequently an income increase.
The Agricultural Climate Risk Zoning works as an instrument of agricultural policy and risk management in agriculture, guiding the farmer about the best planting and sowing of crops season, in order to reduce agricultural losses.
In the 1996/1997 harvest, the Ministry of Agriculture, Livestock and Food supply (Mapa) started to implement the Brazilian agricultural zoning and to annually publish the sowing seasons calendar for crops of social and economic interest.
In 1997, Banco Central do Brasil has published the provisions linked to the granting of costing and insurance credit to the zoning adoption (Resolutions no. 2403 of June 25, 1997, and no. 2427 of October 10, 1997), which has contributed to the reduction of production losses due to impactful weather events, fraudulent requests and costs of 150 million a year. Currently, around 40 crops are contemplated.
To meet the demand of the Federal Government, expressed in the form of a Decree, the agroecological zoning of sugarcane and oil palm crops were elaborated.
The sugar cane AEZ, released in September 2009, aims at the expansion and sustainable production of the crop in the Brazilian territory, from the delimitation of land potential for expansion of cultivation, preferably already occupied by pastures, intended primarily for the production of ethanol and sugar.
On the other hand, the oil palm AEZ was released in May 2010 and aims to guide the expansion of the Brazilian production of the crop, in technical-scientific basis, in order to ensure the sustainability in its economic, social and environmental aspects in the anthropic areas of the following states: Acre, Amazonas, Amapá, Maranhão, Mato Grosso, Pará, Rondônia, Roraima, Alagoas, Bahia, Espírito Santo, Pernambuco, Rio de Janeiro and Sergipe.
There is not a single methodology for zoning; overall, it depends on the objective. It can be regionalized or specific to the given crop or group of crops, but studies are highly dependent on the availability of scientific and technical data and information.
Data and information about soils, climate and crops are raised and systematized in databases to be incorporated into tools such as agro-metereological models, those of geoprocessing and remote sensing and of digital processing techniques.
The environmental and socioeconomic variables are georeferenced and incorporated into the geographic information systems (GIS) to be analyzed, classified and combined (crossed), and presented in the form of maps and reports, or technical notes.
The assessment of the agricultural potential of lands for a particular crop requires a comparison between the eco-physiological demand of the species and the environmental supply in the area where you intend to implant it. Aiming to meet a favorable cost/benefit ratio, this procedure is based on the fact that, for each plant species, there is a set of characteristics of soil and climate to which the species is adapted, and the more away from these conditions, the lower the success in the crop exploration and more intensive and expensive the practice of improving the soil and ploughing condition becomes, and it can make the cultivation and/or technique economically unfeasible.
In the case of the sugarcane AEZ, an evaluation of the potential of the land for the production of sugar cane in a non-irrigated base (without full irrigation) was performed based on the physical, chemical and mineralogical characteristics of the soil spatially expressed in soil surveys and studies on climate risk, related to the requirements of the crop (rainfall, temperature, occurrence of frosts and short summer droughts).
The oil palm AEZ was obtained, basically, by the intersection of climate and land capabilities, with emphasis on interactions between soil and climate.
Advantages and benefits
Zoning, an instrument that informs public policies and decision-making for all agribusiness sectors/stakeholders, allows one to promote the use and occupation of agricultural lands focusing on sustainability and conservation of natural resources; reduction of risks inherent to farming activity (environmental and socioeconomic); increase in production, agricultural productivity and food supply.
The characterization and delimitation of areas that are suitable for agricultural use (land suitability), of areas and classes of climate risk (low, medium and high), and indications for planting and sowing seasons with low climate risk, for each municipality, per crop and cultivar cycle (early, medium or late), and by soil type (sandy, medium and clayey) are presented in the form of technical reports containing maps, tables, and calendar of planting/sowing seasons.
The AEZ is recommended for all crops of social and economic importance, provided that they have the necessary scientific and technical indicators available through agricultural research.
Zoning usually considers objectives and criteria determined by the requester, the composition of the technical team and institutions involved, the availability of scientific and technical data and information, in addition to supplementary research.
For the sugarcane and oil zonings, a multidisciplinary and multi-institutional team was created, led by Embrapa as their coordinator. This team was composed of technical researchers and professionals linked to various Embrapa research centers and Universities, state institutions and other research institutions such as the National Institute of Meteorology (Inmet), the Brazilian Institute for Geography and Statistics (IBGE) and the National Supply Company (Conab).
In the specific case of the Agricultural Climate Risk Zoning implemented by MAPA, Embrapa and partner institutions must develop methodologies for each required crop and pass them on to the Ministry. The Ministry, through the public tender process, hires a company to elaborate zoning for all units of the Federation.