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As China's dairy consumption grows, both the domestic milk production and the importation of dairy products are increasing to meet demand. As a first step toward understanding the environmental impacts of water use in the expanding Chinese dairy industry, life cycle assessment (LCA) was used to calculate the water availability footprint for large-scale production systems in Heilongjiang, a major production region. Comparisons were also made with imported products from the US (California) and New Zealand. The water footprint of milk (cradle to farm gate) produced in Heilongjiang was around 11 L H2Oe (H2O-equivalents) kg-1 fat-protein-corrected milk (FPCM). This compared to 461 and 0.01 L H2Oe kg-1 FPCM for production in California and New Zealand respectively. Accordingly, the water footprints of milk products (cradle to factory gate) produced in Heilongjiang were much lower than those imported from California, but higher than those from New Zealand. From a food industry perspective, shifting the sourcing of dairy products from California to New Zealand or Heilongjiang could greatly reduce the associated life cycle water footprints of dairy-based processed foods. These results highlight that dairy products can be produced with minimal potential to contribute to freshwater scarcity. However, dairy production systems vary, both in production pattern and local environmental context. With the expansion of dairy farming in China, the development of farming systems with high consumptive water requirements should be avoided in water-stressed regions. [ABSTRACT FROM AUTHOR]

Background and Aims: Increased N availability induced by agricultural fertilization applications and atmospheric N deposition may affect plant nutrient resorption in temperate wetlands. However, the relationship between nutrient resorption and N availability is still unclear, and most studies have focused on leaf nutrient resorption only. The aim of our study was to examine the response of leaf and non-leaf organ nutrient resorption to N enrichment in a temperate freshwater wetland. Methods: We conducted a 7-year N addition experiment to investigate the effects of increased N loading on leaf, sheath and stem nutrient (N and P) resorption of two dominant species ( Deyeuxia angustifolia and Glyceria spiculosa) in a freshwater marsh in the Sanjiang Plain, Northeast China. Results: Our results showed that, for both leaf and non-leaf organs (sheath and stem), N addition decreased N resorption proficiency and hence increased litter N concentration. Moreover, the magnitude of N addition effect on N resorption proficiency varied with fertilization rates for D. angustifolia sheaths and stems, and G. spiculosa leaves. However, increased N loading produced inconsistent impacts on N and P resorption efficiencies and P resorption proficiency, and the effects only varied with species and plant organs. In addition, N enrichment increased litter mass and altered litter allocation among leaf, sheath and stem. Conclusions: Our results highlight that leaf and non-leaf organs respond differentially to N addition regarding N and P resorption efficiencies and P resorption proficiency, and also suggest that N enrichment in temperate freshwater wetlands would alter plant internal nutrient cycles and increase litter quality and quantity, and thus substantially influence ecosystem carbon and nutrient cycles. [ABSTRACT FROM AUTHOR]