Technologies for rational water use in Brazilian agriculture

Brazil has the highest water availability of any country in the world. Nearly 20% of all the world’s rivers flow on Brazilian soil. Brazil’s herds of cattle, pigs and poultry are among the largest in the world, and the country uses irrigated agriculture extensively, which accounts for most water consumption (approximately 70% of the water consumed in the world). The Brazilian Agricultural Research Corporation (Embrapa), the largest and most important public institution of Brazilian agricultural research, has attempted to develop environmental technologies in order to minimize the impact caused by the scarcity and pollution of water resources. This paper describes the technologies this institution offers to different regions. For this purpose, a descriptive and exploratory study was conducted in various Embrapa research units. The results showed that research on the rational use of water in agriculture has intensified since the early 2000s. However, the pace of growth in agricultural activities and their impact is much greater than that of the generated technologies, demonstrating the difficulty in striking a balance in this relationship. Furthermore, it is clear that that water scarcity and the increasing pollution of shallow and deep waters are complex issues with no short-term solution.


INTRODUCTION
Brazilian society is embroiled in a number of conflicts regarding the use of water, especially in regions where this resource is historically scarce.Conflict over the use of water tends to intensify due to increasing demand, the pollution of water resources and the instability of the climate.Therefore, seeking solutions for the adequate monitoring and use of these resources is considered a priority by public research institutions and management agencies.
The supply of food is a huge priority in countries that are essentially agricultural, such as Brazil.One of the major challenges is the development and application of rational methods and techniques concerning the use of water in agriculture and raising livestock.
In the agriculture sector, it took a long time for farmers and the government to realize that exploitation of the ecosystem could cripple agriculture in the long term, depending on the methods employed.This occurs through the exhaustion of natural resources like water and soil, which are directly involved in the process.When this connection was made, it inspired a drive to seek new farming methods and technologies that would lead to environmental and economic sustainability.Without this sustainability, any changes that might be made would not endure (WWF, 2002).In this respect, Conceição et al. (2013) emphasize that agriculture is growing at a much faster pace than are efforts to achieve sustainable management of water resources.
According to the Sebrae (2014), agriculture is responsible for the consumption of almost 70% of the water in rivers, lakes and aquifers.However, much of the water is wasted, especially in distribution.Only 15% to 50% of the water intended for irrigation reaches its destination.This means that it is very important to search for new technologies and knowledge that will not only help to preserve natural resources but also result in greater efficiency of distribution.
In this context, Embrapa, as a public agriculture research institution, has a mission to develop technologies and rational methods for the use of water in agriculture and livestock.Thus, the aim of this study is to describe the technologies developed by this institution for the rational use of water in different regions of Brazil.It should be highlighted that the concept of technology used in this work is broad, encompassing knowledge, tools and techniques derived from science and practical experience that are used in the development, production and application of products, processes, systems and services.
The methodology employed is descriptive and exploratory, using secondary data such as websites and articles published in digital and print media.We also reviewed documents maintained by Embrapa, where research on this theme is conducted.
This work is divided into five sections.Following this introduction, the methodology is described.The third section addresses the availability of water in Brazil and agriculture activities.The fourth section presents the technologies developed by Embrapa for the rational use of water in Brazilian agriculture.Finally, we discuss conclusions suggested by our research.

METHODOLOGY
This study is descriptive and exploratory.The Embrapa website was consulted in order to obtain data.The site has clusters of information from 46 decentralized research units.Data and reports from these units were also accessed using corporate internal access programs.To complement the data obtained, each unit was sent a list of the technologies they had developed and asked to confirm the information and provide any other data that was considered relevant.The data were collected and confirmed between 30 April and 2 June 2015.

AVAILABILITY OF WATER IN BRAZIL AND FARMING ACTIVITIES
Brazil can be said to have an ample supply of water resources, although there is some imbalance between availability and need.According to Senra (2001), Brazil has 12% of the planet's water reserves but only 2.8% of the population.In comparison, China has 25% of the population but only 10% of water reserves.According to Tucci et al. (2000), the average surface water production in Brazilian territory is 168,790m3/s.The surface water resources produced in Brazil account for 50% of the total resources of South America and 11% of the resources worldwide.However, the distribution of these resources is uneven, with an excess of water in some regions, such as the Amazon Rainforest, and a shortage in other regions, such as the Northeast (Tucci et al., 2000).
To Gomes and Barbieri (2004), there is considerable disparity between water production and demographic concentration.Less than 20% of national water discharge supplies approximately 95% of the population, while 80% of this production originates from regions occupied by only 5% of the population (Gomes and Barbieri, 2004).
According to Christofidis (2002), of the total water used in the world, around 70% is destined for irrigated agriculture, which is far higher than the demands of the industrial sector (21%) and of the urban sector (9%).In Brazil, the irrigated area corresponds to approximately 18% of total cultivated area, with 42% of total production (Christofidis, 2002).The author points out that, with the incorporation of more efficient technologies and processes for managing the treatment and use of water, this consumption should fall over the years.Even so, it is estimated that by 2025 three billion people will be affected by water shortages and availability will be lower than 1,700 m 3 /ha/year (Christofidis, 2002).
Due to the high consumption of water in irrigated agriculture, most of the technologies and knowledge generated for the rational use of water are focused on this type of farming.According to the Sebrae (2014), almost every method concentrates on the use of climate information to help calculate the irrigation needs of crops and methods for monitoring parameters, such as soil humidity, that enable a significant reduction in the use of water and energy (Sebrae, 2014).
To Garcia and Vieira Filho (2014), Brazilian agriculture and livestock is a modern and highly dynamic activity.It has been highlighted as a source of development and economic stability, providing jobs and income and playing a central role in ensuring food safety and bridging poverty and inequality gaps.Nevertheless, the sector faces considerable challenges in terms of sustainable development.In addition to meeting the new ecological requirements, it must satisfy the growing demand worldwide for farming products.Therefore, preparing the Rev. Ambient.Água vol.11 n. 2 Taubaté -Apr./ Jun.2016 Brazilian economy to meet these goals and challenges is a strategy for future growth, which may result in an increase in exports of farming and livestock products (Garcia and Vieira Filho, 2014).Zamberlan et al. (2014) highlight the need to rethink the use of natural resources in farming and livestock systems.Technologies should be developed with a view to a more rational use of these resources.In the opinion of these authors, the environmental variable should be incorporated into production in order to adopt new technologies that minimize environmental impact.

Regional farming activities
According to Oliveira and Souza-Lima (2003, p. 33), the "development of a region can be explained as the result of the interaction of three forces: allocation of resources, economic policy and social activation".The more intensive farming becomes, and the less concern there is over the availability of resources, the harder it will be for that region to develop.This approach makes it easier to understand the Brazilian agriculture and livestock context, as highlighted by Garcia and Vieira Filho (2014).
When it comes to regional development, it is noted that water shortages due to intensive farming can lead to restrictions on freedom and other issues for the population, as mentioned by Azevêdo et al. (2013).To these authors, "water shortages condemn millions of people to a life of poverty, with precarious living conditions and health issues and limited opportunities.This serves to perpetuate serious inequalities not only between countries but within them" (Azevêdo et al., 2013: p. 5).
Brazil is one of the major producers of sugarcane, cocoa, corn and oranges.Other important crops are soy, tobacco, potatoes, cotton, rice, wheat, cassava and bananas.Annual grain production is approximately eighty million tons.Beef cattle are raised in almost every region, especially Mato Grosso do Sul, São Paulo and the southern states, where there are also dairy cows, pigs, poultry, sheep, goats, donkeys, mules and oxen.Brazil is divided into five major regions: The South, Southeast, Midwest, Northeast and North.These regions each have their own characteristics and diversity in farming and livestock.
Most of the swine and poultry industries are concentrated in the South.This type of farming has a high potential for the pollution of water resources, soil and air (Tucci et al., 2000).
In the Southeast, sugarcane, soy and oranges are grown.The region also has the second largest herd of cattle in the country.
In the Midwest, the major crops are rice, corn, coffee, cotton and soy.The raising of beef cattle is the region's most important economic activity.The Pantanal is located here, which suffers from the effects of economic development and requires soil conservation measures as well as controls on mining and management of the potential impacts of sailing on the Paraguay River.The Cerrado ecoregion has the greatest farming potential in the country, but requires care to avoid disastrous impacts.
In the Northeast, sugarcane, soy, cotton, tobacco, cocoa and fruit are grown.Agriculture is a great challenge, especially in the semiarid region, given limitations such as low precipitation, high temperatures, evaporation, subsoil with little capacity for storing water, low levels of education of the local rural population and a system of land ownership that concentrates income in the hands of a few people (Tucci et al., 2000).
In the North, there has been a rise in the planting of crops such as soy, rice, guarana, cassava, cocoa, coconut, passion fruit and cupuassu.The Amazon Rainforest is located in this region, with a great forest reserve.Despite the capacity for regeneration, the constant deforestation and expansion of the occupied areas, especially close to the Cerrado, has considerable potential for environmental impact.
Rev. Ambient.Água vol.11 n. 2 Taubaté -Apr./ Jun.2016 Due to the economic and social importance of agriculture and livestock and the intensive use of natural resources, especially water, it is essential that technologies be developed to minimize the negative impacts or to enable the rational use of these resources.Tundisi (2003) claims that it is technically possible to achieve greater efficiency in the use of water in agriculture.Investing in the use of new technologies can reduce water consumption by 30% to 70%.Therefore, it is important to assess techniques for more efficient water use together with optimized farming in order to enable gains in crop productivity, avoid impacts on soil and plant systems and to avoid wasting water.
In the next section, we present the main technologies developed by Embrapa for the rational use of water in farming and livestock in the different regions of Brazil.

TECHNOLOGIES DEVELOPED BY EMBRAPA FOR RATIONAL WATER USE IN DIFFERENT REGIONS OF BRAZIL
The Brazilian Agricultural Research Corporation (Embrapa) is the largest and most important Brazilian institution for agricultural research.It operates through a network of 46 decentralized research units and has formed partnerships with a number of public and private institutions.
As a public research institution, it has been charged by the government and society with fostering the sustainability of water use by farming production chains.The institution also defines priorities for water use in basins and closely monitors those that are facing water shortages.While water use is not currently threatened in most of the country, it is important not to lose sight of the issue of efficient water use in diverse economic sectors and activities (Rodrigues, 2015).
According to Embrapa ( 2015), the scientific knowledge generated in recent years proves that it is possible to use water in agriculture rationally and without waste.With the water crisis in important regions of Brazil, it is fundamental that this knowledge be made available to society.Many of these technologies are already being adopted in the field, while others are beginning to attract the attention of farmers (Embrapa, 2015).
It would be opportune to define the word "technology", as it will be used in this work.There are several definitions of the word "technology".According to Kruglianskas (1996) "technology is the set of knowledge necessary for conceiving, producing and distributing goods and services competitively".This encompasses all the knowledge related to a company's activities.
The concept of technology has a broader or narrower scope depending on the focus of analysis.However, it includes not only products, but also knowledge that can be translated into processes and services.Therefore, the concept of technology used in this work is provided by Abetti (1989), who defines technology as "a body of knowledge, tools and techniques derived from both science and practical experience that is used in the development, design, production and application of products, processes, systems and services".
Due to the geographic and climatic diversity of the Brazilian regions, some of the technologies developed by Embrapa are developed for a specific region.Others may be used in any region of the country.These technologies are made known to farmers in several ways, such as field trips, lectures, courses, fairs and demonstrations.Furthermore, Embrapa is supported by rural extension institutions that help transfer these technologies.
Tables 1 to 4 contain summaries of the main technologies developed by Embrapa for the rational use of water in agriculture for the different regions of Brazil.
Rev. Ambient.Água vol.11 n. 2 Taubaté -Apr./ Jun.2016 The technologies developed for the Midwest and the South are for use in irrigated crops (coffee, crops in the Cerrado Region and rice).As mentioned above, these are the crops with the highest water consumption.For the North, characterized by a warm and damp climate, Embrapa developed two methods for use in irrigated watermelon and cashew crops and a practice for the shared use of water, i.e., fish farms and crops.
Of the ten technologies developed for the northeast, seven focus on irrigated agriculture and three on rainwater harvesting, as the region has low levels of rainfall.Therefore, like the other regions, the types of technologies that are developed are practical and users are shown how to use them and improve results.Embrapa has concentrated its efforts on the development of technologies that can be used in all regions of Brazil.Given the diversity of the regions, the technologies are less specific than those that are developed for a particular region.The types of technologies are more varied.In addition to practical technologies and training, they include equipment, software and water analyses.
Since 2000, Embrapa has intensified its research efforts in a drive for technologies that reduce or maximize the use of water in agriculture and livestock.Of the thirty-seven technologies mentioned, twenty-five were developed in the last fifteen years.This is an example of the growing concern over rational water use, which is concomitant with the diminishing availability of this natural resource.
Figure 1 shows that the Embrapa research units located in the northeast and southeast were the ones that developed the most technologies for rational use of water.This fact can be explained by the water shortages in the northeast of Brazil and the existence of large areas of irrigated crops in the southeast.This means that the need for solutions for the rational use of water is more pressing and important.
Most of the technologies developed are practical methods and training courses aimed at irrigated agriculture.
It should be highlighted that knowledge and techniques are also considered "technologies" and can have a considerable effect on the water cycle, with greater groundwater recharging and better regulation of water flow throughout the year.The ability of farmers is essential, for instance, to the increased adoption of soil, plant and irrigation management.This will help make the use of water in agriculture sustainable, especially when irrigation is employed.In addition to greater economic profitability, better quality of farming can be achieved, as excess water can in many cases be harmful (Embrapa, 2015).

CONCLUSION
Despite the efforts by Embrapa in recent years to provide technologies focusing on the rational use of water in agriculture and livestock, this problem cannot be solved in the short term, especially in a country like Brazil that is essentially agricultural.
The results show that in spite of increased research by Embrapa, problems of water Rev. Ambient.Água vol.11 n. 2 Taubaté -Apr./ Jun.2016

Figure 1 .
Figure 1.Number of technologies developed by the Embrapa units by region.

Table 1 .
Technologies developed by Embrapa for the rational use of water in agriculture in the South and Midwest regions of Brazil.
Source: Research data

Table 2 .
Technologies developed by Embrapa for the rational use of water in agriculture in the northern region of Brazil.