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In the context of climate change and food provisioning for a growing global population, the impacts of water consumption on aquatic biodiversity (e.g., river water consumption for irrigation) should be considered in Life Cycle Impact Assessment (LCIA). A previous LCIA method quantifying the potential impacts of river water consumption on fish biodiversity, using a species-discharge relationship (SDR), constituted an essential first step. This method is however limited in terms of regionalization and taxa considered, and predicts the potential risk of local species loss only. Here, we address these shortcomings by developing region-specific SDRs for Europe at various scales (continent, country, and eco-region), and including macro-invertebrate biodiversity. SDR exponents vary from 0.06 to 0.45 between regions, underlining the importance of such regionalization. Furthermore, we provide a new regionalized method which considers the location of water consumption within a river basin, by integrating the concept of longitudinal river zonation. This involves the use of a novel measure of potential loss of species richness, standardizing local species loss to an equivalent of global extinction and reflecting species vulnerability. The new method is applied in a Swiss case-study. The consideration of the location of water consumption within a basin was found to be of high importance in the assessment: potential species loss varied between 4.22 × 10(-3) and 3.95 × 10(-1) species (2 orders of magnitude) depending on location. This work thus provides enhancements in the assessment of potential impacts of river water consumption on aquatic biodiversity and contributes to the ecological relevance of the method.

Wetlands harbor diverse species assemblages but are among the world's most threatened ecosystems. Half of their global area was lost during the last century. No approach currently exists in life cycle impact assessment that acknowledges the vulnerability and importance of wetlands globally and provides fate factors for water consumption. We use data from 1184 inland wetlands, all designated as sites of international importance under the Ramsar Convention, to develop regionalized fate factors (FF) for consumptive water use. FFs quantify the change of wetland area caused per m(3)/yr water consumed. We distinguish between surface water-fed and groundwater-fed wetlands and develop FFs for surface water and groundwater consumption. FFs vary over 8 (surface water-fed) and 6 (groundwater-fed) orders of magnitude as a function of the site characteristics, showing the importance of local conditions. Largest FFs for surface water-fed wetlands generally occur in hyper-arid zones and smallest in humid zones, highlighting the dependency on available surface water flows. FFs for groundwater-fed wetlands depend on hydrogeological conditions and vary largely with the total amount of water consumed from the aquifer. Our FFs translate water consumption into wetland area loss and thus become compatible with life cycle assessment methodologies of land use.

Crop and technology choices in agriculture, which largely define the impact of agricultural production on the environment, should be considered in agricultural development planning. A life cycle assessment of the dominant crops produced in a Peruvian coastal valley was realized, in order to establish regionalized life cycle inventories for Peruvian products and to provide the basis for a regional evaluation of the impacts of eutrophication, acidification, human toxicity, and biodiversity loss due to water use. Five scenarios for the year 2020 characterized by different crop combinations and irrigation systems were considered as development options. The results of the regional assessment showed that a business-as-usual scenario, extrapolating current trends of crop cultivation, would lead to an increase in nitrate leaching with eutrophying effects. On the other hand, scenarios of increased application of drip irrigation and of mandarin area expansion would lead to a decrease in nitrate leaching. In all scenarios the human toxicity potential would decrease slightly, while an increase in irrigation water use would benefit the biodiversity of a nearby groundwater-fed wetland. Comparisons with results from other studies confirmed the importance of regionalized life cycle inventories. The results can be used as decision support for local farmers and authorities.

Global water use is dominated by agriculture and has considerable influence on people's livelihood and ecosystems, especially in semiarid and arid regions. Methods to address the impacts of water withdrawal and consumption on terrestrial and aquatic ecosystems within life cycle assessment are still sparse and very generic. Regionalized characterization factors (CFs) for a groundwater-fed wetland at the arid coast of Peru are developed for groundwater and surface water withdrawal and consumption in order to address the spatial dependency of water use related impacts. Several agricultural scenarios for 2020 were developed in a workshop with local stakeholders and used for calculating total biodiversity impacts. In contrast to assumptions used in top-down approaches (e.g., Pfister et al. Environ. Sci Technol. 2009, 43, 4098 ), irrigation with surface water leads in this specific region to benefits for the groundwater-fed wetland, due to additional groundwater recharge from surplus irrigation water. However, irrigation with groundwater leads to ecological damage to the wetland. The CFs derived from the different scenarios are similar and can thus be used as general CFs for this region, helping local decision-makers to plan future agricultural development, including irrigation technologies, crop choices, and protection of the wetland., (© 2012 American Chemical Society)

Global stress on water and land resources is increasing as a consequence of population growth and higher caloric food demand. Many terrestrial ecosystems have already massively been degraded for providing agricultural land, and water scarcity related to irrigation has damaged water dependent ecosystems. Coping with the food and biomass demand of an increased population, while minimizing the impacts of crop production, is therefore a massive upcoming challenge. In this context, we developed four strategies to deliver the biotic output for feeding mankind in 2050. Expansion on suitable and intensification of existing areas are compared to assess associated environmental impacts, including irrigation demand, water stress under climate change, and the productivity of the occupied land. Based on the agricultural production pattern and impacts of the strategies we identified the trade-offs between land and water use. Intensification in regions currently under deficit irrigation can increase agricultural output by up to 30%. However, intensified crop production causes enormous water stress in many locations and might not be a viable solution. Furthermore, intensification alone will not be able to meet future food demand: additionally, a reduction of waste by 50% along the food supply chain or expansion of agricultural land is required for satisfying current per-capita meat and bioenergy consumption. Suitable areas for such expansion are mainly located in Africa, followed by South America. The increased land stress is of smaller concern than the water stress modeled for the intensification case. Therefore, a combination of waste reduction with expansion on suitable pastures generally results as the best option, along with some intensification on selected areas. Our results suggested that minimizing environmental impacts requires fundamental changes in agricultural systems and international cooperation, by producing crops where it is most environmentally efficient and not where it is closest to demand or cheapest., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Global crop production is causing pressure on water and land resources in many places. In addition to local resource management, the related environmental impacts of commodities traded along international supply chains need to be considered and managed accordingly. For this purpose, we calculate the specific water consumption and land use for the production of 160 crops and crop groups, covering most harvested mass on global cropland. We quantify indicators for land and water scarcity with high geospatial resolution. This facilitates spatially explicit crop-specific resource management and regionalized life cycle assessment of processed products. The vast cultivation of irrigated wheat, rice, cotton, maize, and sugar cane, which are major sources of food, bioenergy, and fiber, drives worldwide water scarcity. According to globally averaged production, substituting biofuel for crude oil would have a lower impact on water resources than substituting cotton for polyester. For some crops, water scarcity impacts are inversely related to land resource stress, illustrating that water consumption is often at odds with land use. On global average, maize performs better than rice and wheat in the combined land/water assessment. High spatial variability of water and land use related impacts underlines the importance of appropriate site selection for agricultural activities.