Congress Resources: Papers, posters and presentations

< Return to abstract list

Incorporated Water In Agricultural Production: The Water Balance Considerations

Congress: 2015
Author(s): Renato Peres (Rio Claro / SP, Brazil), Jos Gilberto de Souza

UNESP1



Keyword(s): Sub-theme 8: Revisiting water paradigms,
Abstract

Renato de Toledo Peres

Masters student in Geography -- IGCE / UNESP / Rio Claro (Brazil)

Researcher, Center for Environmental Analysis and Planning (CEAPLA)

renatperes@yahoo.com.br

+55 19 98238-8895

 

Professor Dr. Jose Gilberto de Souza

Professor, Department of Geography -- IGCE / UNESP / Rio Claro (Brazil)

Researcher, Center for Environmental Analysis and Planning (CEAPLA)

jgilbert@rc.unesp.br

+55 19 3526-9226

 

Introduction

The international market for agricultural and non-agricultural products presents an accelerated growing process and simultaneously the concentration of production that takes place at the sectoral/vertical level by merger and acquisition processes, consolidating monopolies, and spatial level by regional productive specialization, seeking competitive patterns and consolidating territorial dynamics of monopolistic merger. These processes are especially valid when it refers to the primary sectors of the economy, contributing to what is called the commoditization of agriculture, where Brazil stands as a unique example. Big corporations aim to achieve maximum financial profits by the expense of the highest possible productivity. To this end, water, basic resource in agricultural production is exploited to the extreme, which includes, among other sources, the extraction of water in deepwater aquifers for irrigation. These water sources, which should be considered, priority, as strategic reserves, show signs of depletion and scarcity in various areas of intensive farming in Brazil (SOUZA, BORGES, TEIXEIRA NETO, 2010). The dynamics of water exploitation in this case joins two processes examined in this study, on one hand the effective use of resources in irrigated production processes, which gives to the hydrological dynamics a gate in the circuit from the holding of free and confined aquifers. In the other hand, the production standards that have been analyzed by the concepts of virtual water export and your uses reflexes from the green, blue and gray classifications (HOEKSTRA, MEKONNEN, 2011) show a water demand that is established not only in use in its production process but effectively extraction of the physical water supply through the incorporation processes into the product, which we call "consumptive use" and consequent physical export of water. These two processes that integrate the hydrological cycle is reflected in a new water balance model.

 

Methods/Material

The analysis of these processes, the use and incorporation of water resources uses as its empirical basis, Holambra municipality, state of São Paulo, Brazil, which combines effective demands and indicators of water scarcity in the production of flowers for export. The profile of high productivity, specifically floriculture, the high number of depleted wells and alarming levels of drawdown of artesian wells clearly demonstrate the importance of examining this county.

The database component analysis from traditional water balance variables from the formula: ΔS = P -- E -- Q, where ΔS corresponds to the variation of water stored in the soil; P is the total precipitation (rainfall during the period); E corresponds to actual evapotranspiration, and Q runoff (THORNTHWAITE, MATHER, 1955). This process goes on to consider two new variables, as indicated: iW corresponds to irrigated water, and fW corresponds to the physical water. "iW" becomes a new input variable and "fW" is present in the output of agricultural products and marketing outside the geographical area of production water, resulting in a new formula: ΔS = P -- E -- Q + iW -- fW. Will be used well data registered by the Department of Water and Power (DAEE) of the city of Holambra and a statistical analysis to be also considered the volume extracted from wells not awarded to determine the volume of irrigation water (Ai). The values for the physically incorporated water are divided into two parts: Moisture and absorbed by photosynthesis water. The volume refers to moisture is obtained from the dried samples of the products, multiplied by the total production of floriculture in the municipality. As for the calculation of photosynthesis, the chemical equation used is 6CO2 + 6H2O → C6H12O6 + 6O2 where we have the ratio of 108 grams of water used for every 180 grams of glucose (CAMPBELL, REECE, 2010), which is the basis for the formation of the plant. The actual mass of water can be also estimated by the product combustion in laboratory, and compared to the total production.

 

Results and Discussion

The confirmation of the relevance degree of "fW" within the water balance is established through the recognition of the total volume of exported commodities, considering the amount of water incorporated in the production of flowers, but it has bounce in a more general list of exports of Brazilian commodities, such as soybeans that meets export standards on average 14% moisture content (SOUZA, BORGES, TEIXEIRA NETO, 2010), the average total exported without considering the analyzes of incorporation in modeling photosynthesis. The results thus abstracted to a set of primary products strongly impacts the amount of "fW", redefining the previous conceptualizations that the country is simply a great exporter of virtual water, but mainly pointing out that, given the weather conditions and water balance if re-evaluated in its entirety could be considered a country with plenty of water.

 

Conclusion

The questions aimed at work are extremely important and conclusions conductors about the physics of water and its effects on water balance and export virtual, since, in preliminary analyzes, the incorporation of physical water in agricultural products can vary from approximately 95% to very humid or up to about 60% for products with low moisture products, but which are plant compounds, in this case refer to two major products of Brazilian exports in the first case the orange juice and the second refined sugar (PERES, 2012).

 

CAMPBELL, N. A.; REECE, J. B. Biologia. 8ª ed.  Porto Alegre: Artmed, 2010.

HOEKSTRA, A.Y.; MEKONNEN, M.M. National Water Footprint Accounts: The Green, Blue and Grey Water Footprint of Production and Consumption. Value of Water Research Report Series No. 50. UNESCO-IHE, Volume 1: Main Report, 2011.

PERES, R.T. Consumo e Incorporação de Ãgua na Produção de Commodities Brasileiras. Monografia. Rio Claro, UNESP, 2012.

SOUZA, J.G.; BORGES, A.C.G.; TEIXEIRA NETO, J. Commoditização da economia brasileira e a exportação física de água: análise das exportações de soja. In: Waterlat 2010 - Conferência Internacional, 2010, São Paulo - SP. Anais Waterlat 2010 A tensão entre a justiça ambiental e social: o caso da gestão da água. São Paulo - SP: PROCAM/USP  Newcastle University, 2010. v. 1. p. 1-15.

THORNTHWAITE, C. W. & MATHER, J. R. The water balance. Publications in Climatology, New Jersey, Drexel Inst. of Technology, 1955. 104p.

2011 IWRA - International Water Resources Association office@iwra.org - http://www.iwra.org - Admin