Suchergebnisse

Problems of freshwater scarcity and pollution are related to water use by farmers, industries and households. The term 'water users' has always been interpreted as 'those who apply water for some purpose'. As a result, governments responsible for water resources management have traditionally targeted their policies towards those water users. Recently, however, it has been shown that this approach is limited. Final consumers, retailers, traders and all sorts of businesses active along the supply chains of final consumer goods remain out of the scope of water policies. This is strange, given the fact that all water use in the world is ultimately linked to final consumption by consumers. It is therefore interesting to know the specific water requirements of various consumer goods, particularly for goods that are water-intensive, like food items, beverages, bio-energy and materials from natural fibres. This is relevant information for consumers, but also for retailers, traders and other businesses that play a central role in supplying those goods to the consumers. The aim of this report is to estimate the water use related to two products that are typical to Italian consumers: pasta and pizza margherita. We use the water footprint concept as a tool to quantify and localise this water use. The water footprint of a product is the volume of freshwater used to produce the product, measured at the place where the product was actually produced. It refers to the sum of the water use in the various steps of the production chain. Earlier studies showed that, when expressed per capita, Italy has one of the largest water footprints of the world, together with other South European countries and the US. The water footprint of the average Italian is 2330 m3/yr, while the global average amounts to 1240 m3/yr. This study shows that the water footprint of dry pasta made in Italy amounts to 1924 litres of water per kilogram of pasta. The water footprint of one pizza margherita – assuming a total pizza weight of 725 gram – is 1216 litres of water. The impact of the water footprints of pasta and pizza depends on the vulnerability of the water systems where the water footprints are located. The impact of the water footprint of pasta is most severe in Puglia and Sicily, where groundwater overexploitation for durum wheat irrigation is common. The impact of the water footprint of pizza is more diverse. It is concentrated in the first step of the supply-chain of tomato puree and mozzarella, i.e. in the cultivation of tomatoes and the feed crops of dairy cows. The bread wheat used for the pizza base does not have large impacts. The water footprint impact of the tomato puree on the pizza is concentrated in Puglia (groundwater overexploitation and pollution related to tomato cultivation) and Emilia-Romagna (water pollution). The water footprint impact of mozzarella lies mostly in the effects of water use for producing the feed ingredients for the dairy cows. Mozzarella production further poses a potential threat to water quality, mostly in the Po valley, but this problem seems to be properly regulated, although possibly not fully controlled.

In most arid and semiarid countries, water resources management is an issue as important as controversial. Today most water resources experts admit that water conflicts are often not caused by physical water scarcity but poor water management or governance. The virtual-water concept, defined as the volume of water used in the production of a commodity, good or service, together with the water footprint (water volume used to produce the goods and services consumed by a person or community), link a large range of sectors and issues, providing an appropriate framework to find potential solutions and contribute to a better management of water resources, particularly in arid or semi-arid countries. As the most arid country in the European Union, water use and management in Spain is a hot political and social topic. The aim of this study is to analyse the virtual water and water footprint in the semiarid Guadiana basin, both from a hydrological and economic perspective. The trans-boundary Guadiana river basin located in southcentral Spain and Portugal drains an area of 66,800 km2, of which 17% lies in Portugal. The present analysis is carried out for the Spanish side of the basin which has been divided into the Upper, Middle and Lower Guadiana basin and the TOP domain. The TOP domain is a group of three small river basins located near the Guadiana River mouth. In these regions the main green and blue water consuming sector is agriculture, with about 95% of total consumptive water use. In the Upper and Middle Guadiana basins, high virtual-water low-economic value crops are widespread, particularly cereals with low economic productivity of the blue water inputs. In particular, the Upper Guadiana basin is among the most significant in Spain in terms of conflicts between agriculture, with almost no food (virtual water) import, and the conservation of rivers and groundwater-dependent wetlands. On the other hand, in the Lower Guadiana basin and the TOP domain, vegetables and crops under plastic greenhouses are grown for which the economic productivity of the blue water inputs are much higher, using both surface and groundwater resources. The Guadiana basin has already moved into the direction of "more crops and jobs per drop". The aim now is to move towards "more cash and nature per drop", especially in the Upper and Middle Guadiana basin.

The hydrology of the Aral Sea Basin during the past few decades has been largely determined by the decision to develop irrigated agriculture on a large scale to produce cotton for export in the 1960s. The irrigated area has grown to 8 million hectares, using practically the entire available flow of the two main rivers, the Amu Darya and Syr Darya. Almost two decades after the disintegration of the Soviet Union, the five states of the Aral Sea Basin face the challenge of restoring a sustainable equilibrium while offering development opportunities for an increasing population. Sustainable water management is thus an imperative that will require coordinated political action of all the states involved. The Soviet Union established its cotton-producing areas in Uzbekistan, Turkmenistan, Tajikistan, and Kyrgyzstan. Today, while cotton remains relatively important, cereal production to reduce imports has become a priority in all four nations. The cotton crop area has decreased over the past ten years, while that of winter wheat – the main grain crop – has doubled. At 39 per cent of the total (blue and green) water consumption in agriculture, wheat is the largest water-consuming crop in the five basin states, followed by cotton at 33 per cent. The present study analyses the water footprint of Central Asian cotton (Gossypium hirsutum L.), wheat (Triticum aestivum L.) and rice (Oryza sativa L.) production, differentiating between the green and blue components, in order to know how the scarce water resources in the region are apparently allocated.

Wastewater treatment plants (WWTPs) play an important role within the urbanwater cycle in protecting receiving waters from untreated discharges. However, WWTPs processes also affect the environment. Life cycle assessment has traditionally been used to assess the impact of direct discharges from WWTPs and indirect emissions related to energy or chemical production. The water footprint (WF) can provide complementary information to evaluate the impact of a WWTP regarding the use of freshwater. This paper presents the adoption of the Water Footprint Assessment methodology to assess the consumption of water resources in WWTPs by considering both blue and grey WFs. The usefulness of the proposed methodology in assessing the environmental impact and the benefits from WWTP discharge to a river is illustrated with an actual WWTP, which treats 4,000 m3$d 1, using three scenarios: no treatment, secondary treatment and phosphorus removal. A reduction of the water footprint by 51.5% and 72.4% was achieved using secondary treatment and chemical phosphorus removal, respectively, to fulfill the legal limits. These results indicate that when treating wastewater, there is a large decrease in the grey water footprint compared with the no-treatment scenario; however, there is a small blue water footprint ; The authors would like to thank the Spanish Ministry of Science and Innovation (PCIN-2013-074) and the European Union (Marie Curie Career Integration Grant PCIG9-GA-2011-293535 and SANITAS ITN Project agreement 289193). Serni Morera was awarded an FI scholarship from the Catalan Government (2015FI_B2 00071). Lluís Corominas received the Career Integration Grant (PCIG9-GA-2011-293535) from the EU and the Ramon y Cajal Grant (RYC-2013-14595) from Spanish Government. LEQUIA has been recognized as a consolidated research group by the Catalan Government with code2014-SGR-1168. The authors also acknowledge the support from the Economy and Knowledge Department of the Catalan Government through the Consolidated Research Group ...